complete small med surgery 2

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REVIEWER

FOR

VETERINARY SMALL ANIMAL MEDICINE AND SURGERY

University Review Center

LEYTE STATE UNIVERSITY

Visca, Baybay, Leyte

6521-A

Prepared by:

AGNES M. TAVEROS, D.V.M.

2003

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TABLE OF CONTENTS

UNIT NO. TITLE PAGE

PRELIMINARIIES

TITLE PAGE 1

TABLE OF CONTENTS 2

1 FACTORS INFLUENCING DISEASE 3

2 ENVIRONMENTAL CONTROL OF INFECTIOUS 4

DISEASES

3 SKIN DISEASES 7

4 DISEASES OF THE EARS AND EYES 13

5 DISEASES OF THE MUSKULOSKELETAL SYSTEM 14

6 BLOOD, LYMPHATIC AND CARDIOVASCULAR 16SYSTEMS

7 RESPIRATORY SYSTEM 19

8 DIGESTIVE SYSTEM 19

9 REPRODUCTIVE AND URINARY SYSTEMS 26

10 NERVOUS SYSTEM 28

11 ENDOCRINE SYSTEM 30

12 IMMUNE SYSTEM 32

13 INFECTIOUS DISEASES 33

14 ZOONOTIC DISEASES 40

15 PRINCIPLES OF SURGERY 41

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UNIT1

FACTORS INFLUENCING DISEASE

Agent (virus, bacteria, parasite, etc.) + host + environment are involved in a complex interplay thatdetermines incidence, severity and distribution of infectious diseases in an animal population.

TERMINOLOGY

Reservoir of an infectious agent is its natural habitatwhere it survives (ex. soil, water, etc.).

Animal reservoirs are known as carriers. They can be clinical (showing disease) orsubclinical (nooutward signs of disease). The infected animals shed (spread) the disease. Latent carriers shed

intermittently (sporadically).

A pathogenic organism must evolve a mechanism by which to spread from the reservoir or carrier

to other animals in order to perpetuate it. Respiratory infections are usually spread by aerosolproduced by coughing and sneezing. Gastrointestinal infections are usually spread through vomit

and feces. Genitourinary infections are transmitted via urine, semen, and vaginal and fetal fluids.

Occasionally, infectious organisms may be shed by open, draining wounds. Clinical illness is notalways seen in animals that are shedding. A carrier may be apparently symptom-free, yet still be

spreading the disease. Infection potential generally varies inversely with the length of time over

which the disease is communicable. Acute, severe illness is associated with highly contagious

secretions, but the period of time over which the animal is contagious will be fairly short.

The transmissibility of a disease is its communicability. The ability to spread from an infected to a

susceptible host. Transmission can occur between members of the same population (horizontal) or

to succeeding generations (vertical) via the placenta or milk. Not all infectious diseases aretransmissible (ex. systemic mycotic infections originate from the soil).

The four major routes by which infectious agents spread between hosts include 1) direct contact 2)

vehicle or fomite 3) airborne and 4) vector transmission:

Direct contact is the most common means of transmission. This would include any situation where

the susceptible animal comes into direct contact with the infectious agent or ill host.

Vehicles or fomites are often involved in transmission of disease. They are inanimate objects that

may carry or contain the infectious organism. Examples would include using the same food dishes

for a sick animal and a healthy one and spreading the disease via the food pans.

Airborne transmission occurs all the time as with feline upper respiratory infections and humancolds or influenza. Generally, airborne transmission is most likely to occur at distances of less than

one meter. However, some diseases are known to be transmitted over distances of up to several

miles.

Vector transmission requires a living creature to transmit the disease. The vector is usually anarthropod or insect such as a mosquito or tick. On some occasions the vector may be a mammal

such as raccoons and their role in the transmission of rabies.

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ADDITIONAL DEFINITIONS

Epizootiology: the study of occurrence and distribution of disease within a population of

animals

Epizootic: an acute outbreak of a disease

Enzootic: constant incidence of disease in a defined geographical area and population

Sporadic: single or random occurrence of disease

UNIT 2

ENVIRONMENTAL CONTROL OF INFECTIOUS DISEASES

Factors that must be considered when attempting disinfection or sterilization include the

microorganism or agent involved the disinfecting agent, the amount of organic matter presentand the temperature.

Physical Agents

Heat and humidity

Steam under pressure creates a higher temperature than can be achieved by

boiling

Heat kills cells by denaturing cellular protein

121 degrees C at 15 pounds/cubic inch for 13 minutes

126 degrees C at 20 pounds/cubic inch for 10 minutes

Dry heat requires a much longer time period and higher temperature

Radiation

Gamma radiation is used to sterilize some foods (strawberries) and surgical

supplies (gloves, suture material) that can not tolerate high temperatures. The

technology involved is costly.

Ultraviolet light is used in surgery suits but has limited application because of

poor penetration. It only affects surface areas

Filtration

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Filtration involves separating bacteria (particulate matter) from liquids or

gases using some kind of selective barrier.

This method is commonly used for pharmaceutical products.

Chemical Agents

Alcohols

Do not kill spores

Are viricidal with increased exposure time

Are only effective during contactno residual effect

Are primarily an antiseptic agent

Approximately 50% effective

Will dissolve cements (lens cement) and harden plastics

Evaporate

Effectiveness is inhibited by organic debris

Chloride

Chlorine(Clorox) is an example Is inactivated by organic matter

Activity is pH dependent

Corrosive

Unstable. Solutions should be made fresh daily

Forms a carcinogen (trihalomethane) in the presence of organic debris

Is sporicidal, viricidal and fungicidal

Is harsh on tissues in high concentrations

Iodine

Povidone-iodine (Betadine) is an example

Antimicrobial

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Some formulations stain

Inactivated by organic matter

Cytotoxic at high concentrations

Can cause skin irritation and contact dermatitis

Iodophores = iodine + surfactant (povidone-iodine)

Aldehydes

Formaldehyde and glutaraldehyde (Cidexplus) are examples

Tissue toxic, irritating and carcinogenic

Contraindicated for use with living tissue

Used for cold sterilization and preservation of tissue samples

Phenols

Hexachlorophene and carbolic acid are examples

Can be irritating to tissues

Undesirable reactions by cats

Is only bacteriostatic not bactericidal

Some compounds neurotoxic and hepatotoxic

Replaced by more effective compounds

Surfactants (surface-active compounds)

Quaternary ammonia. (Benzalkonium chloride) is an example

Algecidal, bactericidal, viricidal, fungicidal

They are not effective against spores and some viruses

Bland, non-toxic to tissues

Some forms are inactivated by soaps, organic matter, hard water (anionic)

Bigaunides

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Chlorhexidine is an example

Low tissue toxicity

Does not affect gram + cocci or spores

Effective against bacteria, viruses, fungi and yeast

May have decreased efficacy in the presence of organic matter, hard water and

anionic compounds

Ethylene Oxide

Ethylene oxide gas is the most effective chemical agent for sterilization

It is used extensively on surgical equipment that can not tolerate heat exposure

It is carcinogenic and requires specialized equipment and ventilation systems for

proper use

Flammable, explosive, irritating to skin and mucous membranes

When trying to control the spread of a disease, all the discussed factors (microorganism,

disinfecting agent, presence of organic debris, how the agent is spread, susceptibility of the host,etc.) must be taken into consideration. Addressing only one or two of the factors involved will lead

to an inability to control the disease. Remember:

AGENT + HOST + ENVIRONMENT = DISEASE

A few examples:

Even though a dog may be vaccinated for kennel cough it still comes down with thedisease. Why?

There are multiple agents involved in causing the disease complex known as "kennel cough". We do

vaccinate for some of the causative agents BUT not all of them. Animals that are vaccinated may

still come down with "kennel cough" but it will be a much milder form than if they had not beenvaccinated. (AGENT)

A cat with feline leukemia is caged directly across from healthy cats, yet none of

them develops feline leukemia. Why?

Feline leukemia is spread by direct and prolonged contact. By having the cats caged so that they donot have contact with each other you prevent the spread of the disease by controlling the

surroundings. (ENVIRONMENT)

Your practice takes care of quite a few stray cats from the animal shelter and they all

seem to have upper respiratory infections. Why?

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There are lots of contributing factors to this situation but one of the factors is probably the poor

condition (health status) of the stray cats. They are under continuous stress and usually have a

number of other health problems that cause them to have an impaired immune status making themmuch more susceptible to upper respiratory infections. (HOST)

ADDITIONAL DEFINITIONS

Sterilization: all life forms are destroyed including spores. Sterilization is absolute. Applied to

inanimate objects.

Disinfection: destruction of most pathogenic organisms. The risk of infection is reduced to a "safe"level. Applied to inanimate objects

Antiseptic: compound that decreases the population of pathogenic organisms. Resident bacteria are

still present. Applied to living tissue.

Sanitation: decrease the level of bacteria to a safe level of cleanliness

Bacteriostatic (inhibition of growth) vs. bactericidal (killing of bacteria)

Asepsis: freedom from infection

UNIT 3

SKIN DISEASES

Some important points to remember when dealing with skin problems and questions that should beasked of EVERY patient that comes in with a skin problem in his dog or cat so that there is less

likelihood that a diagnosis will be missed:

Take a complete history including when the problem started, duration, diet, any other

health problems, etc.

Ask specifically if the problem is seasonal or if it occurs year round.

Is the animal pruritic or non-pruritic? (Does the animal itch?)

What is the distribution of the lesions? Are the lesions only on one small area or is

the whole body affected?

What do the lesions look like?

Are other animals affected? Any human family members with symptoms? Are there any observable parasites like fleas lice or ticks?

In addition, EVERY patient that presents with a skin problem should have the following diagnostictests performed:

Skin scraping

Wood lamp

Fungal culture (Dermatophyte Test Media-DTM)

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Additional tests that may be indicated depending on initial findings and/or response to therapy:

Skin biopsy

Blood work

Thyroid and/or cortisol tests

Autoimmune test(s)

Bacterial culture and sensitivity Intradermal skin test or serologic allergy test

Cytology

Diet trial to determine food allergies

Provocative exposure for contact allergies

Likewise, the following are the most common lesions of skin diseases:

1. Pustule

2. Crust3. Excoriation

4. Pruritus

5. Bulla6. Alopecia

7. Papules

8. Epidermal collarettes9. Urticaria

10. Ulceration

1) PYODERMA

Pyoderma is an infection of the skin usually caused by the bacteria, Staphylococcus intermedius.

Pyoderma is common in dogs and uncommon in cats.

Pyodermas are usually classified as superficial or deep and primary or secondary. Most pyodermasare secondary and predisposing causes include allergies, parasitic infestations, some other primary

health problem and seborrhea. In cats the disease is rare so pyoderma should be suspected to be

secondary to a primary health problem such as feline leukemia or feline immunodeficiency virus.

Clinical signs:

alopecia, papules, crusts, excoriations and epidermal collarets

animal may or may not be pruritic

areas of involvement: armpits, skin folds, lips, interdigital spaces or any other area that

remains moist is predisposed to infection. However, lesions may be wide spread and involvethe whole body.

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Diagnosis is based on history and clinical signs. Skin scrapings and fungal cultures should be

performed to rule out Demodecosis and Dermatophytosis. Other rule outs include Malezzia

dermatitis and other uncommon crusting diseases.

Treatment consists of appropriate long-term antibiotic therapy (oxacillin, erythromycin,

chloramphenicol, cefadroxil, cehpalexin, amoxicillin/clavulanate, trimethoprim-sulfadizine)

2) DERMATOMYCOSIS/DERMATOPHYTOSIS

A fungus causes dermatomycosis or ringworm. There are three main groups of fungi responsible

for causing this disease: Tricophyton, Microsporum and Epidermophyton. Dermatophytosis is a

zoonotic concern and it can affect all domestic animals. The main mode of transmission is viadirect contact or through fomites such as shared bedding, tack or grooming equipment. Not all

animals or humans that are exposed will contract the disease. Host factors such as age, nutritionalstatus, level of stress, etc. are important in determining susceptibility.

Ringworm grows only in keratinized tissue. As the host mounts an immune response and

inflammation occurs, further spread of the fungus is inhibited. For most healthy individuals, thedisease is self-limiting although it may take several weeks for the infection to resolve. Persistentinfections can occur among immune-compromised individuals and longhaired cats. Asymptomatic

carriers exist, especially cats.

Diagnosis is based on physical examination and laboratory tests. Clinical lesions usually appear as

round areas of alopecia. The animal may or may not be pruritic. Wood lamp is helpful in diagnosingcases ofM canis, but only 80% of the cases will fluoresce. Other fungi do not fluoresce so a

negative response to the Wood lamp is insignificant. Other tests include using Dermatophyte Test

Media (a positive culture turns the media red), identifying hyphae and spores using lactophenol blueand the potassium hydroxide digestion test.

Treatment consists of topical antifungal ointments and shampoos. In generalized cases, systemic

antifungals are indicated.

AGENT COMMENTS SIDE EFFECTS

SHAMPOOS

1) Chlorhexidine Few side effects; antibacterial Occasional irritation; corneal

ulcers

2) Povidone-iodine Not recommended for cats or light-haired animals

Iodine toxicity may occur; stainswhite or light coats

3) Ketoconazole Bathe first with a keratolytic shampoo if

necessary

DIPS

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1) Chlorhexidine Few side effects; antibacterial Occasional irritation; corneal

ulcers

2) Captan Contact sensitizer in people Vomiting in cats

3) Lime-sulfur Antipruritic, antiparasitic, malodorous Stains white or light coats;occasional irritation

4) Povidone-iodine Staining common Iodine toxicity (esp in cats);

occasional irritation

5) Sodium hypochlorite Occasional irritation; will bleach

dark haircoats

PRODUCTS FOR

LOCAL THERAPY

1) Miconazole Available as cream, lotion and spray Occasional local irritation

2) Clotrimazole Available as cream Occasional local irritation

3) Ketoconazole Cream with few side effects

4) Thiabendazole Should be refrigerated; antipruritic,

antibacterial

Occasional contact allergic

reactions

5) Econazole Available as cream

SYSTEMICANTIFUNGAL DRUGS

1) Griseofulvin Divide dose q12h; administer with a

fatty meal

Nausea, vomiting, diarrhea;

idiosyncratic myelotoxicity (esp

in cats); ataxia, pyrexia, icterus,

angioedema

2) Ketoconazole Admisniter the dose divided q12h if

nausea or anorexia occurs

Gastric irritation, anorexia,

hepatotoxicity; idiosyncratic

lightening of haircoat

3) ATOPY

Atopy or allergic inhalant dermatitis is very common in dogs. 10% -15 % of the population may beaffected with predisposition for this disease seen in certain breeds (Terriers, Golden Retrievers,

German Shepherds, Labradors, Shar-peis, etc.). It is an infrequent disease in cats.

The disease usually manifests itself by the time the animal reaches adulthood (3 years old). It

usually starts off as being seasonal in nature but as the animal becomes sensitized to more and more

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allergens, the symptoms will be present year round. Main clinical signs include muzzle rubbing,

foot licking and chewing, pruritus, excoriations from self-mutilation, hyperpigmentation of the skin

and abnormal behavior due to intense itching. Secondary otitis and/or pyoderma may occur.

Diagnosis is based on clinical signs. Pruritus and the seasonal nature (initially) of the disease are

characteristic. The diagnosis is confirmed via intradermal skin test or serologic allergy test.

Treatment can be symptomatic such as the use of corticosteroids and histamines to control itching.

Immunotherapy (hyposensitization) via allergy shots gives the best long-term results. It may also bepossible to avoid or decrease exposure to some allergens once the allergens are identified via skin or

serologic testing.

4) FOOD ALLERGY/FOOD HYPERSENSITIVITY

Food allergies are not as common as atopy, but they do occur. The terms are used interchangiblyand describe symptoms induced by food ingestion in which there are donstrable or highly suspected

immunologic reactions. It seems to be primarily a problem in dogs but can occur in cats. Symptoms

may be confusing and non-specific. The animal will be pruritic and the symptoms will be non-seasonal. The age at onset of clinical signs varies. Clinical signs may include otitis, blepharitis,pruritus, alopecia, and muzzle rubbing. Cats may show signs of miliary dermatitis.

The terms food intolerance or food sensitivity are used when immunologic etiology is unlikelyl

Diagnosis is difficult because the clinical signs are not specific ( although pruritus is the most

common sign) and there is no definitive diagnostic test. Diagnosis is based on history, clinical signsand response to an elimination diet orhypoallergenic test diet. The animal should be fed the trial

diet for 3 months and NO other foods added to the diet. Animals normally respond to the diet within

two weeks. Elimination diets may be difficult to use in cats because they often refuse to eat the new

diet. The most commonly identified allergens are beef and chicken for dogs and fish, beef andchicken in cats. It is possible that the animal may have more than one allergic syndrome. This may

further complicate diagnosis and treatment.

Treatment is based on avoiding exposure to the allergens by feeding specialized diets. Response tosymptomatic treatment is variable but corticosteroids and antihistamines may help in some cases.

5) CONTACT ALLERGY

Occurs as a result of chemicals reacting with skin proteins. The classic example is poison ivy rash

in humans. This problem has been reported in dogs and is usually due to sensitization to plastics

(feed dishes or collars) or substances applied to the skin (dips, etc.). Diagnosis is based on localizedsigns and treatment consists of avoiding the allergen.

6) FLEA ALLERGY

Flea allergy dermatitis is the most common skin disease of dogs. Cats are also commonly

affected. The cat flea, Ctenocephalides felis, is the main cause of the problem; less likely, by Pulexirritans (human flea) and Ctenocephalides canis. It will bite humans. In dogs typical signs include

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chewing. Licking and biting at the tailhead, legs and flanks. "Hot spots" are commonly seen. Crusts,

papules, hyperpigmentation, staining from saliva and sores will develop. The animal will chew until

it self-mutilates. It will be restless, anxious and uncomfortable. Cats develop small, round scabs andcrusts especially around the neck, face and back legs (miliary dermatitis). The condition is usually

worse in the summer months, but can be a year round problem if fleas become established in the

home.

Diagnosis is based on typical clinical signs and the evidence of fleas on the animal (fleas or flea

dirt[digested blood excreted by the flea] in the coat of the dog) which changes to a reddish-brown

colour on contact with water.). Treatment usually consists of any of a number of excellent topical or

oral anti-flea medications now available on the market. All animals in the household must betreated. Environmental controls may be indicated if the infection is severe. If the animal is in

intense discomfort or if secondary infections exist, corticosteroids, antihistamines or antibiotics may

be indicated.

Below is the treatment suggested by Birchard and Sherding:

1) Decreasing Allergic load (Flea Control)a. Environmental indoors and outdoors) treatment using the following compounds that

have activity against flea eggs, larvae and pupae: chlorpyrifos, permethrin, orpyrehtrin in conjunction with a growth hormone regulator such as methoprine,

fenoxycarb) Note: Cats are very sensitive to organophosphates

b. Treatment of unaffected pets with adulticidal flea products lacking flea repellent

effects: chlorpyrifos and permethrin as dips or sprays or foams Note: (permethrindips can cause toxicity in cats)

c. Treatment of Affected pets also with adulticidal flea products; use of systemic

parasiticidal agents is not recommended as flea bites are required for theireffectiveness

7) SARCOPTIC MANGE

Sarcoptic mange or scabies is caused by the mange mite, Sarcoptes scabiei var canis. It is a

zoonotic disease, although infestations in humans are usually self-limiting. Sarcoptic mange can

infect other animals including cats and ferrets. Sarcoptes is spread by direct contact. The adult mitesburrow in the skin causing severe irritation and itching. Clinical signs include pruritus, papules,

crusts, excoriations and secondary bacterial infections. The lesions usually develop on the legs,

elbows, ears and face. The condition can become generalized. Asymptomatic carriers exist.

Diagnosis is based on clinical signs and skin scrapings. Repeated deep scrapings must be performedin multiple location in order to discover mites. In some cases mites may not be found and based on

clinical signs alone a therapeutic trail may be indicated.

Treatment consists of dips that are effective against mites or Ivermectin (not an approved drug for

this use). All animals and humans in the household may need to be treated

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8) DEMODECTIC MANGE

When found in large numbers, the mange mite, Demodex canis, causes demodecosis. The mites are

normal inhabitants of the canine skin and usually do not cause disease. In individuals that areimmunosupressed, the mites overpopulate and cause clinical signs of disease. There is evidence that

there is a genetic predisposition for this problem. It is not a contagious disease.

Clinical signs take on two manifestations, localized and generalized. Localized lesions usually

occur on the head or feet and is seen in animals less than one year old. Alopecia, redness, crusts andpapules characterize the lesions. The prognosis for localized demodecosis is good. Most cases

resolve spontaneously.

Generalized demodecosis has a much graver prognosis. Localized demodecosis can spread and

become generalized. Generalized demodecosis affects the whole body and is characterized byalopecia, crusts, papules and pustules. Animals may be very ill with secondary pyoderma and

lymphadenopathy. Some underlying systemic illness should be suspected.

Diagnosis is based on clinical signs and skin scrapings. The mites are easily found.

Treatment for localized lesions can be topical. Treatment for generalized demodecosis consists ofwhole body dips with amitraz. Success has been reported with ivermectin and milbemycin oxime. If

secondary pyoderma exists, appropriate antibiotic treatment is indicated. Corticosteroids should be

avoided.

Demodecosis has been reported in cats. It is an uncommon disease. It is not caused by the samemite as demodecosis in dogs. Cats have their own species of mite,Demodex cati.

9) CHYLETIELLA

Chyletiella or walking dandruff causes dorsal scaling and itching in dogs and cats. It can spread to

humans so it is a zoonotic disease. There are several mites involved; Chyletiella yasguri is the mainculprit. Diagnosis is based on skin scrapings and the use of a flea comb or clear sticky tape to trap

the mites. Treatment consists of weekly dips or oral Ivermectin.

10) NOTOEDRES CATI

Notoedres caticauses mange in cats. It is an uncommon disease. The mites will infest other animals

including man so it is considered a zoonotic disease. The mite causes severe itching. Crusts and hairloss are seen mainly around the head and neck. Diagnosis is via skin scrapings. Treatment consists

of lime-sulfur dips or oral Ivermectin.

11) OTODECTES CYANOTIS

Otodectes cyanotis causes otitis externa in dogs, cats and ferrets. In theory humans can also beinfected although clinical cases have not been reported. Signs include head shaking, scratching,

alopecia and erythema. Secondary trauma (hematomas) and infections are common. Diagnosis is

based on cytology. The mites will be easily visible. Treatment consists of topical insecticides.

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Unit 4

DISEASES OF THE EARS AND EYES

There are many diseases that affect dogs and cats. Only the three most common problems areincluded. Some eye and ear problems are symptoms or complications of a particular disease. Each

disease will be discussed under the primary systems that they affect, for example, respiratorysystem.

1) ENTROPION

Entropion is an inherited problem of the eyelids. The lid margins roll inwards towards the cornea

causing irritation, tearing and in some cases corneal ulceration and permanent eye damage.

Diagnosis is based on physical exam findings. Surgical correction of the defect is usually required.It is a disease primarily seen in certain breeds of dogs such as Chows, Akitas and Shar-peis.

2) OTITIS EXTERNA

Otitis externa is an inflammation of the external ear canal. It is seen in both dogs and cats. It may

be caused by a number of factors including parasites, allergies, autoimmune diseases,endocrinopathies, chemical irritation, yeast and bacterial infections.

Clinical signs include redness, pain, swelling, itching, discharge, and foul smell of the ear.

Diagnosis is based on clinical signs, cytology, culture and blood work. Treatment is based on the

underlying cause.

3) GLAUCOMA

Glaucoma is a disease seen mainly in dogs. Dogs have the highest incidence of glaucoma, second

only to man. It can be a primary problem or occur secondarily to an eye injury. The disease is

characterized increased intra-ocular pressure that can lead to progressive damage of the retina and

optic disk. The animal will eventually become blind.

Clinical signs vary. The eyeball may be enlarged and painful. The sclera will have prominent blood

vessels. The pupil will be dilated or respond sluggishly to light. The animal may be extremely

painful.

Diagnosis is based on tonometry, opthalmoscopy, goniospcopy, electroretinogram, and visualevoked potential. Treatment may include medical or surgical treatment or both.

UNIT 5

DISEASES OF THE MUSKULOSKELETAL SYSTEM

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1) PATELLAR LUXATION

Patellar luxation is a problem that is seen in both dogs and cats. Miniature breeds of dogs are

especially affected. The patella (kneecap) slips out of place causing the animal pain. This slippagemakes the joint unstable and, long-term, will lead to arthritic changes in the knee. There are a

number of predisposing factors including trauma, obesity and a genetic predisposition.

Diagnosis is based on clinical signs. The animal will be reluctant to bend its leg at the knee joint.

On palpation, the knee can be manually popped in and out of the patellar groove. The knee may bevery painful on palpation. The animal may have a "skipping" gait as the patella pops out of place on

flexion and back into place on extension.

Ideal treatment would consist of surgical correction of the defect known as: trochleoplasty;

chondroplasty; wedge recession; patelloplasty or DeAngelis Technique (fabella to patella tendon).In some cases, medical management might be an option. Weight control and use of anti-

inflammatory and joint fluid modifying drugs may help.

2) CRUCIATE RUPURE

This is primarily a problem of dogs. Rupture of the cruciate ligament in the knee usually occurspost-trauma. The ligament that is torn is usually the anterior/cranial cruciate ligament. This ligament

is responsible for stabilizing the knee. When the ligament is ruptured the knee becomes unstable

leading to secondary osteoarthritis.

Diagnosis is based on physical exam. The animal will be lame. The joint may show evidence ofswelling and pain on palpation. While the animal is lying on its side the clinician should be able to

elicit a cranial drawer sign. This is diagnostic for an ACL rupture.

Treatment should consist of surgical correction. There are a number of surgical options availablebut the purpose of the procedure is to stabilize the knee, hopefully by mimicking the action of theACL as closely as possible. The operations are: patellar tendon procedure; Fibular head

transposition procedure; Fascial Strip Over-the-Top Procedure and the Imbrication Procedure. In

some situations medical management may be attempted. This would consist of weight reduction,rest and the use of anti-inflammatory and joint modifying drugs. This may not be the ideal choice

because even after the initial pain subsides the knee still remains unstable and arthritis will be a

problem in the future.

3) HIP DYSPLASIA

Hip dysplasia is a complex disease that primarily affects middle to large sized breeds of dogs. Hipdysplasia has a genetic basis and the incidence of this disease in some breeds is very high. The main

problem is that the hip (femoral head) does not fit properly into the hip socket (acetabulum).

Because of the instability that is present, over time, arthritis develops. This leads to the clinicalsigns that most people are familiar with. The animal will have difficulty getting up, going up stairs

and jumping up on to higher surfaces. The hind end may wobble or weave as the animal walks.

There may be muscle wasting of the hind legs due to lack of use. The gait of a dyplastic dog isdescribed as a "bunny hop". The animal is painful and so is reluctant to stride out. On physical

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examination the clinician may find that the animal is very painful when the hip joint is manipulated.

There may be a grating sound or feeling when the hip is swung through the range of motion. Range

of motion may be limited. The hip may be so unstable that the clinician can actually "pop" the hipout of the socket (Ortolanis sign).

Radiographs may help with making the diagnosis. It is important to note that clinical signs and

radiographic findings do not always correlate. The animal may be extremely painful and showminimal radiographic changes while an animal that is not painful may have horrible hips

radiographically.

Treatment consists of several options. Medical management with anti-inflammatory and joint fluid

modifying drugs, exercise restriction and weight control is a possibility in older animals that are nottoo severely affected. In younger animals a surgical option should be considered. Pelvic osteotomy

(5-13 months old dogs), femoral head and neck excision arthroplasty (all ages but most successful

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Osteochondrosis is a problem of development of the cartilage. It can be seen in the hock, shoulder,

elbow and stifle. It is a disease seen in middle to large breed rapidly growing dogs. It is believed to

have a genetic basis. Defects in cartilage development lead to an uneven joint surface and manyfragments. This uneven surface and the presence of debris in the joints causes arthritis to develop.

The animal will be lame and painful on manipulation of the joint. Radiographs of the affected joint

may help to establish the diagnosis. More than one joint may be affected.

Treatment consists of surgically removing any cartilage debris or loose cartilage flaps. The use of

anti-inflammatory and joint fluid modifying drugs also helps.

UNIT 6

BLOOD, LYMPHATIC AND CARDIOVASCULAR SYSTEMS

1) CARDIAC INSUFFICIENCY AND CARDIAC FAILURE

The most common cause ofcardiac insufficiency in dogs is mitral valve disease. The valves fail to

properly close causing regurgitation (back flow) of blood. This regurgitation will cause turbulence

and the clinician should be able to hear a holosystolic murmur. The back flow of blood will alsocause increased pressure in the left atrium and ventricle and the pulmonary veins. This increased

pressure will cause fluid to accumulate in the lungs causing pulmonary edema. The animal may

cough, have exercise intolerance or in some cases, syncope. Its mucous membranes may be blue orgray colored and it will have a delayed capillary refill time.

Diagnosis is based on history, physical exam, chest radiographs, electrocardiogram and

echocardiography. There are definite breed predisposition for certain cardiac diseases so patient

signalment may be extremely helpful.

Treatment depends on the stage of the disease. Diuretics may be used to decrease pulmonary edema.

Digitalis glycosides are used to help increase the force of cardiac contraction. After-load reducers

such as Enalapril are used to decrease hypertension. Antiarryhtmics may be indicated as well.

Many animals survive for years with appropriate medical therapy.

2) CARDIOMYOPATHY

Cardiomyopathy is a disease of the heart muscle itself. The heart looses its ability to contract

effectively. There are many different causes of cardiomyopathy. The cause of dilatedcardiomyopathy in most cases is unknown. This form of the disease is seen most frequently in

large breed dogs. Hypertrophiccardiomyopathy is seen most frequently in cats. The cause is alsounknown.

Clinical signs include weakness, exercise intolerance, coughing and collapse. A murmur may be

heard. In cats a gallop rhythm may develop (third heart sound). Diagnosis is based on history,

physical exam, chest radiographs, electrocardiogram and echocardiography. Echocardiography canbe especially helpful because it allows visualization of the heart chamber walls and valves.

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Treatment consists of the use of diuretics, digitalis glycosides and vasodilators. Prognosis is

guarded. Survival rates are usually brief even with aggressive treatment and range from two months

to two years.

3) LYMPHOMA/LYMPHOSARCOMA

Lymphosarcoma occurs in both dogs and cats. In cats, the underlying cause is infection with FelineLeukemia Virus. In dogs the cause is not known. There is an increased incidence of this disease in

certain breeds such as Golden Retrievers, Boxers and Basset Hounds. A genetic predisposition orbasis for this disease in dogs is suspected.

Clinical signs are extremely variable and depend on the anatomical site affected by the malignancy.

In dogs, the most common form is the multi-centric. The dog will present with generalized enlarged

lymph nodes. In cats, the gastrointestinal and mediastinal forms predominate. With thegastrointestinal form the cat may present with weight loss, anorexia, vomiting, diarrhea and

abdominal distention. With mediastinal form, respiratory signs will be seen.

Diagnosis is based on clinical signs. Further tests that might be indicated include biopsy, cytology,blood work, radiographs and ultrasonography.

Treatment depends on the location and stage of the disease. Surgical excision is an option if the

malignancy is limited to a single site. Chemotherapy helps but survival time is limited to 6-12

months.

4) HEMANGIOSARCOMA

Hemangiosarcoma is an aggressive soft tissue tumor that may arise spontaneously or due to sunexposure. They metastasize easily. This type of tumor is common in large breed dogs especially

German Shepherds and Golden Retrievers. Th most common sites for occurrence include theextremities and the spleen. Diagnosis is based on physical exam, radiographs and biopsy. Excisionis the treatment of choice. Survival rates depend on the presence or absence of metastasis.

5) VON WILLEBRANDS DISEASE

Von Willebrands disease is an inherited deficiency of Factor VIII related antigen. Factor VIII

related antigen aids in platelet adhesion and slows clearance of Factor VIII from circulation. It is agenetic disease that has been described in many animal species. It is seen most frequently in dogs

and has been described in over 54 breeds. There is a high incidence of this problem in Dobermans,

Shelties and Scottish Terriers. The animal usually does not exhibit clinical sign until after a surgery

or trauma when prolonged bleeding occurs. The animal will have an adequate platelet count andnormal clotting times. The buccal mucosa bleeding time may be used as a screening test or as a

diagnostic test. Affected animals will have a prolonged bleeding time, however, this test is not

always accurate. VonWillebrands Factor assay is the best way to detect and quantify the problem.

Treatment, if necessary, consists of fresh or fresh frozen plasma transfusion or if the animal has

bled profusely, whole blood transfusion.

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6) HEMOPHILIA

Hemophilia is a deficiency of either Factor VIII (hemophilia A) or Factor IX (hemophilia B). It is a

genetic disease that has been reported in dogs, cats, humans, and horses. The defect is carried on theX chromosome so it is a sex-linked trait. Females are usually asymptomatic carriers and males are

affected with clinical signs. Carriers are difficult to detect.

Animals with hemophilia can not clot and will spontaneously bleed. Bleeding may not occur until

after an injury or surgery. Clotting times are prolonged (ACT & APTT). Treatment consists oftransfusion of fresh or fresh frozen plasma or whole blood. The animal is transfused 2-3 times a day

until the bleeding stops.

7) CONGENITAL DEFECTS OF THE HEART

The most frequently detected cardiac defects are septal defects (atrial or ventricular) and patentductus arteriosus (PDA) and are reported mainly in dogs. Patent ductus arteriosus is the most

common problem and occurs when the shunt between the aorta and pulmonary trunk fails to close at

birth. Abnormal shunting of blood from the left side of the heart to the right side of the heart leadsto a volume overload, pulmonary congestion and ultimately heart failure. A continuous "machinerymurmur" may be detected by the clinician Echocardiography will help to determine the diagnosis.

Animals may survive for years with medical management depending on the severity of the defect.

Surgical correction is the best choice for long-term survival.

Unit 7

RESPIRATORY SYSTEM

Most common respiratory diseases of cats and dogs are of viral or bacterial etiology and will bediscussed in detail under the unit on infectious diseases.

Here are some important definitions:

Hemothorax: blood in the chest. Seen most commonly post-trauma such as a hit-by

car.

Pyothorax: pus in the chest. Seen most commonly after a penetrating injury to thechest. This is a frequently seen syndrome in intact male cats post cat-fights.

Pneumothorax: air in the chest. Seen most commonly post-trauma.

Chylothorax: chyle or lymph in the chest. This occurs because of a rupture of the

thoracic duct often after being hit-by-car or in the case of cats, being kicked.

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Unit 8

DIGESTIVE SYSTEM

1) EOSINOPHILIC GRANULOMA COMPLEX

Eosinophilic granuloma complex is a hypersensitivity reaction that has been reported in cats, dogs

and horses. It is most commonly seen in cats. Sensitivities to insects, foods, bacteria and other

environmental factors have been documented. There is a genetic predisposition to this disease

although the cause of many cases remains undetermined (idiopathic).

Cats may develop ulcers, plaques or granulomas. Common sites include the lips, thighs and pads of

the feet. In dogs most lesions are seen in the mouth. Siberian Huskies are the breed most likely to be

affected.

Diagnosis is based on the typical appearance (ulcer, plaque or granuloma) and location of thelesions. Biopsy of the lesion with histopathology is helpful. Histopathology will show inflammation

with a high number of monocytes, plasma cells and neutrophils. Eosinophils may or may not be

present on the tissue biopsy. There is usually a peripheral eosinophilia.

Like any disease of an allergic nature, the emphasis should be on eliminating the allergen from theenvironment if possible. Insect control and dietary trials are indicated. Allergy testing and

hyposensitization would be the next step if necessary. Antibiotics should be utilized in non-

responsive cases. If the cause remains undiagnosed the use of steroids and other anti-inflammatorydrugs can be used to treat the symptoms.

2) GASTRIC DILATATION-VOLVULUS

Gastric dilatation-volvulus occurs primarily in large breed dogs such as German Shepherds, Great

Danes, Irish Setters, Doberman Pinschers and Standard Poodles. It is a life-threatening emergencythat involves the torsion (twisting) of the stomach on its axis and the accumulation of gas in the

stomach. This twisting and bloating can cut off the blood to supply to vital organs and lead to death.

The exact cause of this disease is not known. There may be a genetic or familial predisposition butthis has not been proven.

Diagnosis is based on physical examination and radiographs. The animal will show signs of

restlessness and pain. The abdomen may be grossly distended. The dog may drool, gag and have dry

heaves. As the disease progresses the animal will go into shock. Heart rate will be elevated, bodytemperature will fall, mucus membranes will be gray or muddy and capillary refill time will be

delayed. Radiographs will show a rotation of the stomach over to the right side of the body (the

right lateral abdominal view is preferred).

Treatment is geared towards the treatment of shock and stabilization of the patient before taking itto surgery. This includes the placement of catheters, fluid administration, decompression of the

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stomach, administration of steroids and other anti-shock therapy. Surgical correction of the volvulus

is indicated (gastropexy). Several different methods of surgical correction are used and all seem to

have approximately the same success rate. If the animal is only managed medically the chances ofreoccurrence are about 75%. Surgical correction offers a 5-11% reoccurrence rate. This is a serious

disease. Approximately 70% of the animal die even with aggressive therapy.

3) PANCREATITIS

Pancreatitis is a disease that is seen most often in middle aged, obese, female dogs. It is alsoreported in cats. The exact cause of this disease is not known. It is thought that a high fat diet

predisposes an animal to developing pancreatitis. Basically there is a change in cell membrane and

vascular permeability and pancreatic enzymes leak out. The enzyme causes tissue damage andnecrosis and the pancreas digests itself.

Signs of this disease are extremely variable and often non-specific. The animal may have vomiting,

diarrhea, abdominal pain, abdominal distention, depression, anorexia, fever, dehydration and

icterus. Diagnosis is based on clinical signs and confirmed with a hemogram, blood chemistries

(amylase and lipase levels), radiographs and ultrasonography.

Therapy

Fluid therapy and pain relief are the cornerstones in supportive care.

Concurrent problems (such as lipidosis or enteritis) need to be addressed.

Feed; do not fast, unless animal is vomiting.

Even with the vomiting animal, designing a nutritionally supportive protocol is of great

importance especially to cats due to this species predisposition for developing lipidosis. Thus, cats

should be fasted for no longer than 48 hours utilizing anti-emetics as necessary. In the few

intractably vomiting cats, total parenteral nutrition or jejunostomy tube feeding may be advisablefor 710 days.

Trickle feeding: For animals requiring nutritional support, but who are vomiting, it is useful to

know about trickle feeding. This is a spin-off of the technique of parenteral/IV feeding that hasbeen adapted to enteral (i.e., GI) feeding. If an animal with an esophageal or gastrostomy tube

vomits whenever the volume fed is more than a ridiculously small amount then trickle feeding is

the answer.

Anti-emetics: When the use of anti-emetics is being considered it should be noted that the livermetabolizes these agents, so their clearance rates may be decreased. Doses should be reduced

accordingly.

Generic Name Product Dose (feline)

Chlorpromazine Thorazine, Largactil0.5 mg/kg q8h IMProchlorpromazineCompazine 0.1 mg/kg q6h IM

Diphenhydramine Benadryl 2.04.0 mg/kg q8h PO, 2.0 mg/kg q8h IM

Dimenhydrinate Dramamine 8.0 mg/kg q8h POProchlorpromazineDarbazine 0.50.8 mg/kg q12h IM, SQ

+ Isopropamide

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Metoclopramide Reglan 12 mg/kg constant rate infusion IV over 24 hours

Ondansentron Zofran 0.10.15 mg/kg slow push IV q612 hours prn

Dolasetron Anzemet 0.6 mg/kg IV q24h

Also of critical importance are: analgesics for the comfort of the patient, a test dose of 0.10.2

mg/kg oxymorphone IV to see if the patient improves over the approximately four hour effective

period. If that is the case, then constant rate infusion of a narcotic may be considered or atransdermal fentanyl patch (Duragesic) for continuous relief.

Corticosteroids are indicated in an acute shock presentation. Other anti-inflammatories are not

currently recommended; nor have any benefits been seen with the use of antacids, anticholinergics,

GI hormones (somtostatin, glucagon), or calcitonin. Dopamine has been useful in acuteexperimental feline pancreatitis. Metronidazazole may be useful for both its immunomodulatory

and antimicrobial effects.

Antibiotics are only indicated if the diagnosis of a suppurative pancreatitis has been made. In this

case, antimicrobial selection is best made with the knowledge of a sensitivity spectrum. Note that a

suppurative pattern may be seen on histology in a sterile pancreatitis caused by enzyme damage.Complications of ACUTE pancreatitis that may arise include DIC, thromboembolism, cardiac

arrhythmia, sepsis, acute tubular necrosis, pulmonary edema, and pleural effusion. It has beensuggested that a low dose of dopamine (5 mcg/kg/min) diminishes the severity of the disease. To

prevent bacterial translocation, cover these patients with broad-spectrum antibiotics.

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Prognosis

Prognosis depends on the type of pancreatitis as well as the degree of duration and severity. Many

cats have chronic, low-grade smoldering pancreatitis and with accurate diagnosis and appropriate

therapy, can live long lives. Treatment is geared towards resting the pancreas and supportive care.

The patient should not be given anything to eat or drink for at least several days depending on theseverity of the disease. If necessary the animal can be kept off of food for weeks and supported with

parenteral nutrition or a jejunostomy tube that by passes the pancreas. Intravenous fluids, histamineblockers, analgesics and antibiotics should be provided.

The prognosis can be very poor. If the animal is caught in the early stages, the chances for survival

improve. Relapses are common.

4) INTESTINAL PARASITES

Roundworms are common especially in puppies and kittens. They are a zoonotic disease and can

cause visceral larval migrans and occular larval migrans in humans. Toxocara canis is the mostimportant because of its pathogenicity. T canis can be transferred transplacentally, via ingestion and

transmammary. T cati can only be transmitted via ingestion or transmammary while T leonina istransmitted only by ingestion. With T. canis, puppies as young as 1 week of age will already have

parasites present in their intestinal tracts.

Puppies and kittens typically develop a pot-bellied appearance and are "poor doers". They may

vomit worms or pass them in their feces. The animals may have diarrhea and coughing (frommigrating larvae). The parasites may cause intestinal blockage, pneumonia and death. Diagnosis is

based on clinical signs, the presence of worms in the vomitus or stool or the detection of eggs on

fecal examination.

There are numerous excellent worming medications available. Puppies and kittens should bedewormed starting at 2 weeks of age and dewormed every 2 weeks until they reach 12-16 weeks of

age. Adult animals should have a fecal check performed every six months and dewormed if

necessary.

Hookworms are common in warmer climates.Ancylostoma caninum is the main culprit. Uncinariastenocephala, Ancylostoma tubaeforme and Ancylostoma braziliense can also cause problems. A.

caninum is transmitted via ingestion, skin penetration and transmammary. Hookworm larvae can

also penetrate the skin of man causing coetaneous larval migrans or eosinophilic enteritis.

These parasites are blood suckers so infected animals become anemic, hypoprotenimc, lethargicmalnourished and may have tarry stool. Dermatitis and pneumonia may also be seen.

Diagnosis is based on clinical signs and the detection of parasite eggs on fecal examination.

Treatment is with any one of a number of deworming medications. The same schedule should be

followed as is recommended for the treatment of roundworms.

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Whipworms are not as common a problem as hooks and roundworms. Transmission of Trichuris

vulpis is by ingestion. These parasites cause GI upset with weight loss, diarrhea and occasional

fresh blood in the stool. Although These parasites have occasionally been associated witheosinophilic enteritis in man.

The eggs of this parasite can survive in the environment for up to 5 years so environmental control

is essential. Whipworms have a long life cycle (12 weeks) so effective control depends on givingthe patient medication at least twice at 6-12 week intervals.

Tapeworms are often seen in dogs and cats. All rely on an intermediate host for transmission.

Dipylidium caninum is the most common tapeworm and is transmitted by fleas. Taenia

taeniaefomis is seen in cats and depends on mice and rats for transmission. Echinoccocus may beseen in dogs that have access to carcasses.

Tapeworms rarely cause any signs of disease in dogs or cats. Owners often report the problem when

they see white egg packets in their pets stool.

Echinoccocus is a major zoonotic concerm as humans can develop metacestodes (Hydatid CystDisease) from these tapeworms.

Treatment can be accomplished with a one-time administration of a deworming medication such as

Praziquantel. Owners should limit their pets access to the intermediate host. Flea control is

indicated as well.

Feline GI Pearls

Inflammation is often characterized by infiltration of lymphocytes and plasma cells in many feline

conditions: inflammatory bowel diseases, pancreatitis, cholangiohepatitis, triaditis, and

stomatitis. Inflammation of any of these tissues may also be suppurative in nature or even

granulomatous, but lymphocytic/plasmacytic (l/p) infiltrates are most common. This implies thepresence of antigenic stimulation chronically and has implications in the therapeutic approach to

any of these conditions.

6) IBD

Inflammatory Bowel Disease may cause vomiting, diarrhea, both or neither in cats. Symptoms seendepend on the degree of inflammation and impairment of absorption as well as the location (where

and how much) of the inflammatory lesions. Gastric inflammatory changes and those in the upper

small intestines will be likely to cause vomiting. Colitis in the cat may also cause vomiting.Occasionally cats will be asymptomatic other than weight loss. Palpably thickened intestinal loops

may be present and enlargement of the mesenteric lymph node may be noted. Mild dehydration may

be evident.

Folate and cobalamin. Cats, unlike dogs, do not appear to develop small intestinal bacterialovergrowth (SIBO), rather, the normal cat has a much higher population of GI flora than does that

of dogs. Thus, subnormal folate levels are not indicative of SIBO in cats; however, folate deficiency

may occur with severe, chronic malabsorptive proximal small intestinal disease. In addition, 50% ofcats with exocrine pancreatic insufficiency (EPI) have subnormal folate levels. Cobalamin

deficiency is most likely the result of malabsorption secondary to EPI in cats. Some cats with

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chronic intestinal disease (e.g., triaditis or "IBD" may be deficient in either of these vitamins and

may benefit by supplementation if their assays verify subnormal levels.

7) CHOLANGITIS/CHOLANGIOHEPATITIS COMPLEX (CCHC)

Inflammation of the biliary tree and/or liver parenchyma may be suppurative or non-suppurative.

The non-suppurative form is more common and is often lymphocytic/plasmacytic in character. The

clinical presentation includes a vague history of inappetance/anorexia OR polyphagia, lethargy, aswell as possibly nausea, vomiting, diarrhea and weight loss. The signs may have a chronic

intermittent occurrence. On physical examination, signs of dehydration, weight loss, muscle

wasting, icterus, salivation, palpable liver margins, cranial abdominal tenderness or firmness may

be present. Suppurative and non-suppurative CCHC cannot be differentiated based on history andphysical examination alone; both forms may or may not present with an elevated temperature.

Biopsy is required for differentiation. Wedge biopsy provides necessary architectural information

that a Tru-cut or fine needle aspirate doesnt.

Cats with CCHC often have hyperbilirubinemia and bilirubinuria, but these do not differentiate

the conditions from other hepatic, pre-hepatic or post-hepatic causes of icterus. In patients with

bilirubinuria, lack of urobilinogen should increase suspicion of extra-hepatic bile duct obstruction.Increases in activities of serum alkaline phosphatase (ALP), alanine transferase (ALT), and gammaglutamyl transferase (GGT) may be present to varying degrees but do not distinguish between

suppurative and non-suppurative CCHC. Cats with hepatic lipidosis usually have markedly

increased ALP activity compared to ALT activity and have normal GGT activity. In contrast, catswith CCHC usually have ALP and ALT increases of equal magnitude or the increase in ALT is

greater than ALP; GGT activity is usually increased as well. Bilirubinuria is ALWAYS significant

in the cat.

It is important to realize that some patients may have chronic CCHC resulting in decreasedfunctional liver mass and therefore no increases in ALT, ALP, or bilirubin may occur. There may be

variable changes in albumin, glucose, BUN, and cholesterol. If you believe that liver disease ispossible, a liver function test is indicated. Use the combination of pre- and post-prandial serum bileacid measurement to assess liver function. With cirrhosis, penacillamine or methotrexate may be

beneficial in reducing the progression of fibrosis.

Hepatic biopsy is preferred over FNA or Tru-cut biopsy. With FNA, not only are you restricted in

what you harvest, but also the condition of that sample is mutilated by the aspiration action andslide preparation. Some types of cells do not exfoliate readily (mesenchymal neoplasias such as

fibrosarcoma, for example); with FNA, you only get a cytological diagnosis of whatever cells are

sampled easily and may not get a real picture of the underlying disease process. Additionally,orientation of the cellular reaction within tissue is critical in differentiating what role neutrophils or

lymphocytes play. For example, peribiliary inflammation and periportal inflammation definedifferent disease processes and may indicate different therapy and different prognosis.

Vitamin K1. Fifty percent of cats with HL have prolonged PIVKA (Proteins Induced in VitaminK Absence or Antagonism) times or other prolonged coagulation tests and require vitamin K1

therapy. It takes cats < 7 days to become vitamin K deficient. Cats who have been on antibiotics

may have fewer organisms in their bowels to make vitamin K. Vitamin K is absorbed in theproximal small bowel and recycled by the liver (via the vitamin K epoxidase cycle). Thus, in small

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bowel disease (such as IBD induced fat malabsorption), as well as in liver diseases (especially in

hepatic lipidosis), low vitamin K levels may predispose to occult coagulopathies. Factors II, VII, IX

and X, as well as protein C and protein S (antithrombotic proteins), are vitamin K dependent. If thepatient is jaundiced or nauseous, then the vitamin K1 must be given SC rather than orally because

intestinal absorption is poor (0.51.0 mg/kg q24h X 34 days or until coagulation normalizes). If

too much vitamin K1 is given, an oxidative toxicity may develop and supplementation of vitamin E

as an antioxidant may be required.

8) TRIADITIS

Unlike the dog, in the cat, the pancreatic duct enters the common bile duct before it opens into the

duodenum. When there is disease (e.g., inflammation, infection, neoplasia, stasis) in the smallbowel, it may ascend into the common bile duct and, from there, affect the pancreas and the rest of

the biliary tree. Similarly, disease in the biliary tree or pancreas may affect the other two regions.

When this occurs, it is termed triaditis. This complex is so common, that ultrasonographicevaluation of the abdomen is very helpful to try to determine which organs are involved.

9) CHOLECYSTITIS

Cholecystitis generally presents as a vague malaise with inappetance and dehydration, (pretty much

like everything else in the cat). Vomiting may be present. While this too may involve alymphocytic/plasmacytic inflammatory infiltrate of the gall bladder wall, it more often is

suppurative. If surgical evaluation occurs, and the gall bladder looks inflamed or if it does not

compress and empty normally, or if ultrasound is suggestive of cholecystitis, bile aspiration and

culture (aerobic and anaerobic) should be performed.

10) EXTRA HEPATIC BILE DUCT OBSTRUCTION (EHBDO)

This is a cause for acute onset of vomiting and malaise in a patient. Plain radiographs may show a

radiodense object in the region of the gall bladder; ultrasound confirms that the location is the bile

duct, as well is able to detect inspisations that are not radiodense. A urinalysis detects this problemearly, as there will be the presence of bilirubin but a lack of urobilinogen in the sample. Blood work

will show a marked increase in bilirubin and eventually cholestasis and some hepatocellular injury

(increased ALT). This constitutes an emergency and requires surgical correction.

11) GASTROINTESTINAL (GI) LYMPHOMA

Lymphoma is the most common form of GI neoplasia in cats. In the past, alimentary lymphoma has

been given a poor/grave prognosis in most of the literature.

LymphoCYTIC GI lymphoma is readily treated using prednisone and clorambucil. The mediandisease free interval was 20.5 months (range 5.849 months). Rescue is achieved with

cyclophosphamide. Cats with lymphoBLASTIC lymphoma respond poorly to chemotherapy using

either CVP (cyclophosphamide, vincristine, pred) or ACOPA (CVP + doxorubricin and L-

asparaginase). Of interest also is the observation that cats with lymphoBLASTIC lymphoma aremore likely to have recurrences of abdominal masses.

GI biopsies. Good quality biopsy samples are essential. Diagnostically, more is better. Endoscopy

is a tool with advantages and disadvantages. The biggest problem with endoscopy is the limited

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areas one can visualize and the limitations of partial thickness biopsy. GI lymphoma may be

patchy, may be limited to the serosal and muscularis layers of the bowel, can be missed, and the

remaining tissue may have lymphocytic/plasmacytic infiltrates and be interpreted as IBD. Inaddition, it is important to recognize that severe IBD may progress to lymphoma. Thus, it is

important to make a definitive diagnosis of IBD early on and suppress the inflammatory response.

Endoscopy. In a retrospective study comparing radiographic, ultrasonographic and endoscopicfindings in cats with upper GI IBD, it was found that the clinical signs and ultrasound findings

correlated best with histologic grade of IBD and that ultrasound identified more abnormalities than

upper GI endoscopy.

Unit 9

REPRODUCTIVE AND URINARY SYSTEMS

1) PYOMETRA

Pyometra is a bacterial infection of the uterus characterized by a purulent discharge from the vulva.

I t can affect both dogs and cats but is much more common in dogs. Animals that are prone topseudopregnancy, that are older or that have received mismating shots (estrogen) are more likely to

be affected. The organism that is most often involved in uterine infections isE. coli.

Diagnosis is fairly easy when the condition is "open" with actual pus draining from the open cervix.

The diagnosis can be much more difficult if it is a "closed" pyometra with no visible uterinedischarge. Animals will be anorectic, depressed and may have abdominal distention. They may

exhibit signs of polyuria, polydypsia and vomiting. They may or may not have a fever.

Leukcoytosis is common.

Treatment involves providing supportive care and performing an ovariohysterectomy as soon as it issafe for the animal to undergo anesthesia. In animals that must be salvaged for breeding purposes,

prostaglandins may be used to empty the uterus and antibiotics initiated based on culture and

sensitivity. There is increased risk to the patient with medical management and a reoccurrence ofthe pyometra is likely.

2) PSEUDOPREGNANCY OR FALSE PREGNANCY

Pseudopregnancy occurs at the end of diestrus and is caused by lowered progesterone levels. It is

common in dogs. Bitches may actually lactate, act restless, exhibit nesting behavior and "adopt" anobject to take the place of a pup. Medical treatment is not recommended nor is it necessary.

Pseudopregnancy will resolve spontaneously within 2-3 weeks. If the owner is distressed by the

changes in their pets behavior, they should have an ovariohysterecotmy performed. There is some

evidence that pseudopregnancy predisposes the animal to pyometra.

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3) CRYPTORCHIDISM

Cryptorchidism is a hereditary condition seen in dogs and cats. It is a more common problem in

dogs. One (unilateral) or both (bilateral) testes may fail to descend. In order for propre sperm

production to occur, the testis must be at temperatures 1-8 degrees lower than normal body

temperature. Bilateral cryptorchidism renders the male infertile. Unilateral cyrptorchids can stillproduce viable sperm from the one descended testis. The testicles continue to produce testosterone

no matter what their anatomical location, so cryptrochid males will have normal secondary sexualcharacteristics and mating behavior. The location of the undescended testis can be anywhere from

immediately caudal to the kidney to just outside the scrotum in the inguinal ring. These animals

should not be used for breeding, as the condition is hereditary. In addition, there is an increased riskof cancer developing in the undescended testis (Sertoli Cell Tumor). These animals should be

castrated.

4) FELINE UROLOGIC SYNDROME (FUS) OR FELINE LOWER URINARY TRACT

DISEASE (FLUTD)

This is a common problem of cats characterized by straining to urinate (stranguria), blood in theurine (hematuria) and urinating in small quantities, frequently (pollakiuria). Cats may also urinate in

unusual places (kitchen sink, bathroom floor, etc). The causes of lower urinary tract diseases are

numerous and often the actual underlying cause may not be identified. There is however, a well-known syndrome in cats that involves the presence of sand and stones (urolithiasis) in the urine.

Feline urolithiasis occurs in both male and female cats but males are at greater risk of obstruction

due to the longer and narrower diameter of their urethra. The uroliths are usually composed of

struvite crystal with a variable amount of gelatinous material mixed in. A smaller percentage iscomposed of calcium oxalate.

Diagnosis is based on clinical signs and confirmed with a urinalysis. Additional diagnostics may be

required for refractory cases and would include chemical testing of the uroliths, radiographs and

ultrasonography.

Treatment consist of supportive care, antibiotics IF an infection is present, reduction of magnesium

in the diet and reducing the urine pH to less than 6 (prescription diets). If the animal is blocked,

more aggressive therapy will be required to remove the urethral plug and restore urinary output.Blocked cats can rapidly become extremely ill and die.

5) RENAL FAILURE OR INSUFFICIENCY

Renal failure can be acute (anti-freeze toxicity) or chronic (any one of numerous causes of renal

disease). The goals in acute renal failure is to prevent further damage to the kidneys whilesupporting the patient long enough to allow recovery. The goal in chronic renal failure it to treat

what ever the underlying cause was that precipitated the event while trying to re-establish

homeostasis.

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Signs include polyuria, polydipsia, vomiting, weight loss, anorexia, dehydration, diarrhea and oral

ulceration. Blood work will show increased blood urea nitrogen (BUN), creatinine and

phosphorous. In some chronic cases, anemia may be present. Urinalysis will show a decreasedspecific gravity. Care must be taken to rule out any one of a number of diseases that can cause

similar clinical signs.

Prognosis depends on the underlying cause. In acute renal failure the prognosis is good if theunderlying cause can be identified quickly enough and treatment initiated. In chronic renal failure,

the prognosis is dependent on the rate of progression of the disease. Some animals live comfortably

for years.

6) PROSTATITIS

Enlargement of the prostate gland may be due to benign hyperplasia, bacterial infection oroccasionally cancer. Bacterial infection is most commonly associated withE. coli.

Clinical signs include tenesmus (straining to defecate), hematuria, difficulty urinating (stranguria),

depression, pain and fever.

Diagnosis is based on clinical signs, abdominal and rectal palpation, aspirates of the prostate,evaluation of ejaculate, culture and sensitivity, blood work, radiographs and ultrasonography.

Treatment consists of long-term antibiotics that have been selected based on culture and sensitivity.

Castration may help by promoting involution of the prostate.

Prognosis is guarded. Prostatitis can be difficult to resolve.

Unit 10

NERVOUS SYSTEM

1) INTERVERTEBRAL DISK DISEASE

Intervertebral disk disease affects primarily dogs. There is a genetic predisposition for this disease

in certain breeds such as Dachshund, Corgis, Shih Tzu, Pekingese, Lhasa Apso and Basset Hounds(dogs with long backs). The signs are variable but include pain at the herniation site, paresis, flaccid

or rigid paraplegia, arched back, reluctance to move, weakness, fecal and/or urinary retention.

Diagnosis is based on clinical signs and a through neurologic examination. Radiographs and/or a

myelogram can help in establishing the diagnosis.

Treatment for mild cases may include cage rest, anti-inflammatory drugs and pain medication. In

severely affected animals, surgery is the only option. If the animal is caught early enough before

spinal cord damage has occurred, the prognosis is good.

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2) CERVICAL INSTABILITY "WOBBLER"

Wobbler is caused by spinal cord compression from cervical vertebrae instability. It is a disease

primarily of large breed dogs such as Great Danes and Dobermans. There is a suspected genetic

predisposition to this problem.

Clinical signs include inability to properly place feet (proprioceptive deficits), paresis and paralysis

(may affect front, back or all four feet). Animals may be painful in the neck and resist neck

manipulation.

Diagnosis is based on clinical signs. Radiographs and/or a myelogram may be helpful.

Treatment is symptomatic and includes anti-inflammatory drugs and pain medication. The dogshould be restrained using a chest harness and not a halter or collar. If the condition is severe,

surgery to stabilize the cervical vertebrae may be the only option. The prognosis is guarded.

3) EPILEPSY

Epilepsy is a disease characterized by recurrent seizures. There is usually no detectable brain lesion.The cause of the disease is unknown. It is known to be inherited in many breeds of dogs including

Golden Retrievers, Labrador Retrievers, German Shepherds, Shetland Sheepdogs, Saint Bernards

and many other breeds. Males appear to be more commonly affected than females.

Typically animals will have generalized convulsive seizures. The seizures are more likely to occurwhen the animal is resting at night or early in the morning. The dog will become stiff, fall over,

paddle, vocalize, chomp, urinate, defecate and salivate. The seizure may last for seconds or for

minutes.

Diagnosis is based on clinical signs and the ruling out of all other possible causes of "seizures".Realize that the owner may inaccurately identify collapse from cyanosis, renal failure, etc. as

"seizures". A complete medical work up including bloodwork should be performed on these

animals.

Treatment is based in the severity of the seizures. If the dog only seizes occasionally (1x/3 months)then treatment may not be indicated. If the seizures occur on a regular basis, treatment with

Phenobarbital +/- potassium bromide is indicated. Treatment is for the life of the animal.

In some situations an animal may have prolonged or repeated seizures (clusters). These animals

may require emergency treatment with intravenous anti-seizure drugs to control the seizures.

Animals that begin seizing after 2 years of age and that do not exhibit cluster seizures usually

respond well to treatment and have a good prognosis. Animals that begin seizing before 2 years of

age or that have cluster seizures have a much more guarded prognosis.

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Unit 11

ENDOCRINE SYSTEM

1) HYPOTHYROIDISM

Hypothyroidism is the most commonly diagnosed endocrinopathy in dogs. It is caused by a

deficiency of thyroid hormones and is characterized by a low metabolic rate. It is seen primarily in

dogs. There is a breed predisposition to this disease. Breeds most commonly affected include

Golden Retrievers, Shetland Sheepdogs, Schnauzers as well as others. Females are more likely to beaffected than males. The actual cause of the disease is suspected to be immune mediated.

Clinical signs include weight gain, heat seeking behavior, exercise intolerance, hair loss, dull hair

coat and increased incidence of pyoderma. Bloodwork may show anemia and hyperlipidemia.

Diagnosis is based on clinical signs and the result of thyroid hormone assays.

Treatment consists of thyroid hormone replacement therapy and treatment of any underlyinginfections with antibiotics. Response to treatment is gradual and may take up to 3 months before

improvement is noted.

Prognosis is excellent but treatment must continue for the life of the dog.

2) HYPERTHYROIDISM

Hyperthyroidism is the most commonly diagnosed endocrinopathy of cats. It is caused by excessproduction of thyroid hormone from hyperfunctioning nodules in the thyroid gland. These nodules

are benign in 98% of the cases.

Clinical signs include poor appearance and body condition, hyperactivity, tachycardia, galloprhythm and heart murmur. Blood work may show evidence of elevated liver and kidney values

associated with some of the more severe complications of hyperthyroidism.

There are several treatment options. Medical treatment involves the use of methimazole (Tapazole)

to shrink the thyroid gland. Methimazole is associated with undesirable side effects. Radiotherapyinvolves the use of radioiodine to shrink the thyroid gland. Access to appropriate facilities for this

treatment may be a problem. Surgical therapy involves the surgical removal of the thyroid gland.

This procedure involves some risk form anesthesia as well as possible surgical complications.

Radiotherapy is the best choice for the patient.

Prognosis depends on the stage at which the disease is diagnosed. The earlier treatment is received

the better the prognosis. In uncomplicated cases the prognosis is excellent.

3) DIABETES MELLITUS

Diabetes mellitus is a fairly common endocrinopathy that affect both dogs and cats. It is usually

caused by a deficiency of insulin. It is seen more commonly in certain breeds of dogs such as

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Terriers, Poodles Dachshunds and Schnauzers. Diabetes is more common in female dogs and in

male cats.

Clinical signs include polyuria, polydipsia, inappropriate urination, weight loss, polyphagia,vomiting, anorexia, depression, obesity, muscle wasting, jaundice, cataracts and hepapatomegally.

Diagnosis is based on clinical signs. Blood work will help in establishing the diagnosis. Fastingblood glucose levels will be greater than 200mg/% in the dog and 250mg/% in the cat. Glucosuria

will also be present.

Treatment consists of twice a day administration of injectable insulin administered subcuataneously.Diet should be a high fiber low fat food fed twice a day prior to insulin administration. Exercise

helps to lower insulin requirement so regular, consistent exercise is recommended. The amount of

insulin required varies from patient to patient. The animal will be hospitalized and a glucose curveplotted to determine optimum amount and time of insulin administration. The animal should be

monitored on a regular basis to keep glucose levels within the ideal range of 100-200-mg/%. Oral

hypoglycemic agents (glipizide) may help.

Prognosis with treatment is good. Treatment, in all but a few cases, must continue for the life of theanimal.

4) HYPERADRENOCORTICSM "CUSHINGS DISEASE"

Hyperadrenocorticism is due to an excess production of cortisol by the adrenal cortex. There may

be several underlying causes: pituitary tumor or hyperplasia producing too muchadrenocorticotropic hormone (ACTH) or adrenal tumors (benign or occasionally malignant). It is

also possible to cause iatrogenic hyperadrenocorticism with the administration of glucocorticoids

(steroids). This is one of the most common endocrinopathies of dogs. It is rare in cats. Most dogs

with adrenal tumors are female. Poodles, Dachshunds and Boston Terriers appear to be at higherrisk for this disease.

Clinical signs include polyuria, polydypsia, obesity, hair loss, lethargy, muscle atrophy, thin skin,

pendulous abdomen, hyperpigmentation, pyoderma. comedones and muscle weakness. Diagnosis isbased on clinical signs. Blood work will show elevated glucose, cholesterol and liver enzymes.

Urinalysis will reveal a low specific gravity often with evidence of a urinary tract infection.

Additional testing using the high dose dexamethasone suppression test or plasma ACTH levels willbe helpful in differentiating pituitary dependent hyperadrenocorticism from adrenal dependent.

Radiographs, ultrasound, cat scan (CT) and magnetic resonance imaging (MRI) may also help.

Treatment involves administering mitotane (o, p-DDD) to shrink the adrenal gland and decreasethe amount of cortisol produced. Surgery may be indicated for a malignant adrenal tumor, but this israre. Prognosis depends on the underlying problem. Generally patients respond well to treatment

unless the tumor is malignant.

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Unit 12

IMMUNE SYSTEM

1) ANAPHYLAXIS "HYPERSENSITIVTY REACTION"

Anaphylaxis occurs when the body releases the contents of mast cells (histamines, leukotrines andbradykines) in response to foreign substance introduced into the body (injection, ingestion or

exposure).

An antibody:antigen reaction occurs of the mast cell membrane causing degranulation. This is

associated with IgE antibodies. Some animals produce a higher level of reagenic antibody so itappears that there is a familial/genetic predisposition for this problem. It is primarily a problem of

dogs but has been reported in many species. A common cause of anaphylaxis is the leptospirosis

portion of the DHLPP vaccine in dogs.

The primary organ affected is the animals airway. The airway constricts and the animal will havedifficulty breathing. Other clinical signs include salivation, hives, colic, vomiting diarrhea,

bradycardia, cyanosis and pruritus.

Diagnosis is based on clinical signs.

Treatment consists of removal of the antigen if possible and anti-histamines. In severe cases, shocktherapy will be required. Avoidance of the allergen is the only way to prevent this problem.

2) SYSTEMIC LUPUS ERYTHEMATOSUS

Systemic lupus erythematosus is an immune complex disease that is characterized by heightened

antibody responsiveness with production of autoantibodies. This disease has been reported in dogsand occasionally in cats. It is believed to have a genetic basis.

Symptoms include synovitis, oral ulcers, skin lesions, myositis, neuritis, meningitis, arteritis,

myopathy and glomerular nephritis. The most common manifestation in dogs is autoimmune

hemolytic anemia and or thrombocytopenia. Glomerular nephritis and psychosis are more likely tobe seen in cats.

The disease is characterized by the deposition of antinuclear antibodies in the cell. Diagnosis is

based on clinical signs and the identification of the antinuclear antibodies (ANA) via various tests.

Treatment is designed to suppress the immune system to prevent further deposition of

autoantiboides. Glucocorticoids are the drugs of choice. If necessary other stronger chemotheraputicagents can be used. Diagnosis is guarded. Relapses are common.

3) PEMPHIGUS

Pemphigus is an autoimmune diseases characterized by the production of antibodies against

substances in the cell layers which cause separation of the cells. Pemphigus is seen in much more

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frequently in dogs as and rarely in cats. Typical lesions include blisters erosions, and secondary

bacterial infections. Lesions are commonly seen at the mucocutaneous junction.

Diagnosis is based o clinical sings and skin biopsies.

Treatment is aimed at suppressing the immune response. Glucocorticoids are the drug of choice.

Stronger chemotheraputic agents may need to be used if initial response to therapy is poor.

4) AUTOIMMUNE HEMOLYTIC ANEMIA

Autoimmune hemolytic anemia is characterized by the production of autoantibodies against red

blood cells.

It is a disease that is seen most commonly in middle aged female dogs.

Typical signs include pallor, lethargy, spleenomegally, icterus, billirubinemia, tachycardia,

hemoglobinuria, thrombocytopenia, tachypnea, icterus, bleeding, anemia, decreased packed cell

volume, rouleaux and red blood cell aggregation.

Diagnosis is based on clinical signs and a positive Coombs test result. The Coombs test detectsantibodies against red blood cells.

Treatment included the use of glucocorticoids or other immune suppressing drugs. Blood

transfusions are controversial because the introduction of more foreign protein may actual cause the

production of additional antibodies. Blood MUST be cross-matched.

Relapses are common so the prognosis is guarded.

Unit 13

INFECTIOUS DISEASES

1) RABIES

Rabies is an acute encephalomyelitis that occurs in mammals. It is zoonotic. It is caused by a virusand is transmitted via bite wounds. Occasionally it is spread by aerosol (bat strain). The incubation

period is extremely variable. In dogs it can take from 3 weeks to 6 months for an animal to show

clinical signs of the disease.

Clinical signs are neurologic. The animal may be lethargic and depressed (dumb rabies) or

hyperactive and aggressive (furious rabies).

Diagnosis is based on clinical signs and examination of the brain for the virus (immunofluorescent

antibody-IFA).

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Treatment is not effective. Prevention with vaccinations is the key. Puppies and kittens should be

vaccinated at 12 weeks of age and again at one year of age. Adults should be vaccinated every one

to three years depending on state regulations and the incidence of rabies in the area. Vaccinationsare available for humans at high risk of exposure. In the United States humans are most often

exposed to rabies by feral cats or wildlife (bats). A successful oral vaccine for wildlife has also been

developed.

2) CANINE PARVOVIRAL ENTERITIS "PARVO"

Parvo is gastroenteritis of acute onset and variable morbidity and mortality. It is caused by a virus

and transmitted via feces, fomite and direct contact. It infects dogs. Remember that this virus is

highly contagious. Infected animals should be isolated and precautions taken to prevent spread ofthe disease.

Clinical signs include vomiting, diarrhea, dehydration, fever, leukopenia, soft cough, painful

abdomen and myocarditis in puppies.

Diagnosis is based on clinical signs, typical blood work (leukopenia) and immunologic testing ofthe feces for virus (ELISA test).

Treatment consists of supportive care and antibiotics if indicated for secondary bacterial infection.

In some cases canine anti-parvo serum has been used.

Prognosis is variable. Many animals survive with aggressive supportive care.

3) CANINE CORONAVIRAL ENTERITIS "CORONA"

Corona is a gastroenteritis of acute onset very similar to Parvo but not as severe. A virus causes it

and a vaccine is available.

4) FELINE RESPIRATORY DISEASES

This group of diseases includes feline viral rhinotracheitis (FVR), feline pneumonitis (Chlamydia

psittaci), mycoplasma and feline calicivirus (FCV). Recent studies indicate that Bordetella and

Pasturella may also be involved in this complex. These diseases are not zoonotic with the exceptionof chlamydia, which has been reported to cause conjunctivitis in humans and Bordetella, which is

thought to cause respiratory disease in susceptible individuals.

Clinical signs include coughing, sneezing, pneumonia, conjunctivitis, ulcerative keratitis, oral

ulcers, depression, anorexia, dehydration, fever, nasal discharge, salivation and ocular discharge.

Diagnosis is based on clinical signs. It is difficult to determine which of the etiologic agents is

involved or if several agents may be contributing to the disease. FCV is more likely to cause oral

ulceration while FVR is more likely to cause ocular lesions.

Treatment is based on supportive care. Antibiotics are indicated if a bacterial component issuspected. There have been mixed results with anti-viral agents.

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Prognosis is good. A few animals may develop chronic disease such as a non-responsive sinusitis.

Cats that have recovered from FVR will be c

complete small med surgery 2

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