GROUP 5: 3GMT

Matawaran, Luis Paolo

Mercado, Coleen Iris

Miranda, Renz

Montalbo, Carlo

Navarro, Francis

Osea, Rachelle

Family Vibrionaceae:

I. Vibrio spp.

General Characteristics:

Grows well at very high pH (8.5-9.8) Rapidly killed by acid Grows well at 37ºC Ferments sucrose and mannose (cannot ferment arabinose and inositol) Halophiles Can grow on media containing 6% NaCl

Virulence Factors:

Entero toxin – cholera toxin or choleragen Ability to induce hypersecretion of electrolytes (Na+, K+, HCO3

-)

Microscopic morphology:

Gram negative rods Pleomorphic under suboptimal conditions Comma shaped or curved bacilli (only in the initial gram stain of the clinical specimen) Usually appear as small , straight rods (on prolonged cultivation) Asporogenous 05-08 µm x 1.5-3.0 µm

Colony morphology:

Vibrio cholorae Large yellow colonies in TCBS, Opaque and granular in transmitted light

Vibrio parahaemolyticus Beta hemolytic in BAP, green colonies (TCBS)

Vibrio vulnificus Blue-green colonies in TCBS

Vibrio alginolyticus Large yellow colonies in TCBS

Culture Media:

SBA (Sheep Blood Agar) Chocolate agar - large colonies that appear smooth, opaque and iridescent with greenish hue. Mac -Conkey agar - pathogenic vibrios usually grow as nonlactose fermenters Thiosulfate Citrate Bile Salts sucrose agar (TCBS) - Selective and differential. Differentiates sucrose-fermenting

species (yellow colonies) from nonsucrose-fermenting species (green colonies)

Biochemical Tests:

TESTS

GROUP 1 GROUP 2 GROUP 3 GROUP 4 GROUP 5 GROUP 6V.

cholerae

V. mimic

us

V. metschniiko

vii

V. cincinnatien

sis V. hollisae

V. damsel

a

V. fluviali

s

V. alginolytic

us

V. parahaemolytic

us

V. vulnific

us

V. harver

yiNutrient broth w/o Nacl + + - - - - - - - - -Nutrient broth w/ 1% Nacl + + + + + + + + + + +

Oxidase test - + + + + + + + +Nitrate reduction test - + + + + + + + +Myo-Inositol Fermentation V + - - - - - - -Arginine dihydrolase - + + - - - -Lysine decarboxylase - V - + + + +Ornithine decarboxylase -

Pathogenesis:

Most common in the clinical laboratory1. V. cholerae (serogroups O1 and non-O1)2. V. parahaemolyticus3. V. vulnificus4. V. alginolyticus

1) Vibrio cholera - Patients with infection experience a “rice water” stool sample. May experience:

Dehydration Hypovolemic shock Metablic acidosis Rapid fluid & electrolyte loss Death

2)V. parhaemolyticus

Self limited gastrointestinal diseases Kanawaga phenomenon – hemolysin and virulence

3)V. vulnificus

Primary septicemia Wound infection

4)V. Alginolyticus – least pathogenic

II. Plesiomonas spp.

General Characteristics:

Gram-negative comma bacilli Polarly flagellated pathogenic bacterium Motile Habitat is fresh water Oxidase positive Facultative anaerobe Glucose fermenter

Virulence Factors:

Endotoxin production Beta-hemolytic Cholera-like enterotoxin production Large plasmid for invasion

Colony Morphology

Grows readily on most routine media Shiny, opaque, slightly raised center, smooth Late-lactose fermenters Non-hemolytic Grows on most media routinely used in the clinical laboratory 18-24 hours of incubation at 35°C, shiny, opaque, nonhemolytic colonies appear. Can grow well on CIN (cefsulodin-irgasin-novobiocin) as opaque colonies with an opaque apron.

Pathogenesis:

1) Plesiomonas Intestinal

Gastroenteris Watery secretory diarrhea Colitis

2) Plesiomonas Extraintestinal

Veterinarians and like jobs are more prone Bacteremia Meningitis

Biliary tract disease

Family Campylobacteraceae:

I. Campylobacter spp.

General Characteristics:

Gram negative, slim, motile and spirally curved rods All are Oxidase positive All are asaccharolytic All are strict anaerobes or microaerophilic Each cell has one polar flagellum Recognized world-wide as an important food borne pathogen

Virulence Factors:

Motility and Adhesion - One of the most important aspects of virulences in Campylobacter is its nature of interaction with intestinal cell lines

Flagellum (protein: flagellin) Chemotaxis - important for intestinal colonization Toxin production : Enterotoxins and Cytotoxins

Colony Morphology:

Moist or ‘runny-looking’ Spreading Usually non-hemolytic Some are round and raised others are flat Tend to be colorless or gray Some produce tan or slightly pink coloration Does not ferment carbohydrates As moisture decreases colonies may form round convex glistening colonies with minimal spreading

*Campylobacter mucosalis and Campylobacter hyointestinalis can produce a dirty yellow pigment

Campylobacter jejuni Moist, spreading, runny looking, non hemolytic, ‘runny-looking’, round and raised others are flat

Campylobacter fetus subsp. fetus Smooth, convex, translucent Campylobacter mucosalis and Campylobacter hyointestinalis

Dirty yellow colonies

Microscopic morphology:

Curved

Non-spore forming Gram negative rods 0.2-0.9 µm x 0.5-5.0 µm Single polar flagellum Enteric campylobacter

as long as spirals S-shape Seagull-wing

Microarophilic (<5%)

May appear as coccobacilli (from older cultures or when exposed to air)

‘Darting-motility’ on hanging drop

Stains poorly with gram stain

Carbolfuchsin is the recommended counter stain

If sarfranin is to be used, counterstaining should be extended for 2 to 3 minutes

*Arcobacter spp. have a similar microscopic appearance to Campylobacter spp. *Helicobacter pylori may appear similar to Campylobacter spp. But Helicobacter spp. Have multiple flagella at

one pole

Culture Media:

Medium Base Antimicrobial agent

CAMPY blood agar plate Brucella agar10% sheep red blood cells

Vancomycin Trimethoprim Polymyxin BAmphotericin BCephalothin

Skirrow’s Oxoid blood agarLysed, defibrinated horse red blood cells

Vancomycin Trimethoprim Polymyxin B

Butzler Thioglycolate fluid with agar added10% sheep red blood cells

Bacitracin Novobiocin Actidione Colistin Cefazolin

CCDA ( Charcoal cefoperazone deoxycholate agar)

Nutrient agarCharcoalSodium deoxycholate

Cefoperazone Amphotericin B

Biochemical Tests:

Catalase

NitrateReduction

Urease

H2S

Hippurate Hydrolysis

Indoxyl AcetateHydrolysis

15 C

Growth 25 C

42 C

Nalidixic Acid

Cephalothin

C. Jejuni subsp. Jejuni

+ + - - + + - - + + -

C. jejuni subsp. doylei

V - - - V + - - - + +

C. coli + + - V - + - - + + -

C. lari + + - - - - - - + - -

C. fetus + + - - - - - + - - +

C. hyointestinalis

+ + - + - - - + + - +

C. upsaliensis

- + - - - + - - + + +

C. concisus - + - V - - - - + - -

C. curvus - + - V V V - - + + ND

C. rectus V + - - V V - - W + ND

Pathogenesis:

Abdominal pain Cramps Bloody diarrhea Fever and chills Nausea and vomiting Guillain-Barré syndrome – associated with infection; due to cross reaction with nerve cells in an

autoimmune response. Weakness of lower limbs progress in ascending manner.

II. Helicobacter spp.

Helical, curved or straight bacilli 0.5-1.0μm x 2.5-5.0 μm Lophotrichous Appear coccoid in older cultures Microaerophiles

1-2 mm in diameter Translucent, convex colonies Slight hemolysis Optimal growth temperature is at 35-37°C

Pathogenesis:

1) Helicobacter pylori – recognized by immune system but Ab produced are not protective.

Gastric infection Low-grade inflammatory process Chronic superficial gastritits Type B gastritis – stomach lining inflammed Associated with gastric carcinoma

Family Aeromonadaceae

I. Aeromonas spp.

All are Oxidase positive Glucose fermenters Habitat are aquatic environments Gram negative bacilli Grow well on MacConkey agar Facultative anaerobe

Motile Gram (-) straight rods, Single polar flagellum 1.0-3.5μm x 0.3-1.0μm asporogenous

Virulence Factors:

Endotoxin production Enterotoxin production Vero cell cytotoxin Hemolysin Cytotoxic toxin

Colony morphology:

Grows readily on most differential media used for enteric bacteria Large, round, raised, opaque colonies Smooth mucoid surface Hemolysis varies on SBA

o But most clinical species are strongly beta hemolytic except for Aeromonas caviae (which is nearly always non-hemolytic or alpha-hemolytic at best)

Pigmentation (translucent and white to buff colored) No growth on media containing 6% NaCl Some are lactose fermenters (ex. A.caviae) Appear as large round, raised, opaque colonies. Sheep blood agar Most major clinical species, such as A. hydrophila, A. veronii biovar sobria, and A. jandaei display strong β-

hemolysis.

Aeromonas hydrophila, Aeromonas veroniibiovar sobria, Aeromonas jandaei

Strongly beta-hemolytic

Aeromonas caviae Non-hemolytic or alpha-hemolytic

Biochemical Tests: (for differentiation of Aeromonas from Helicobacter)

Catalase

NitrateReduction

Urease

H2S

Hippurate Hydrolysis

Indoxyl AcetateHydrolysis

15 C

Growth 25 C

42 C

Nalidixic Acid

Cephalothin

A. butzleri

-W + - - - + +

+ V V -

H. pylori + V + - - - - - V - +

H. fennelliae

+ - - - - + - - - + +

H. cinaedi

+ + - - - V - - - + +

Pathogenesis:

1)Aeromonas Intestinal Infections

Enteric Pathogen like Shigella, Salmonella and V. cholerae Several forms of diarrhea Cholera-like disease Traveller’s diarrhea

Most are self limiting but in the extremes of age and immunocompromised it is advisable to take meds.

2) Aeromonas Extraintestinal Infections

Septiciemia Meningitis Wound infection Some sp. are invasive to liver, GI tract, respiratory tract and billiary ducts.