Dr.k.vishnuvardhan babuMD

Abnormal frequent passage of loose stools

OR

Abnormal passage of stools with increased frequency, fluidity, and weight, or with increased stool water excretion

Acute diarrhea

Sudden onset in a previously healthy person

Lasts from 3 days to 2 weeks

Self-limiting

Resolves without sequelae

Chronic diarrhea

Lasts for more than 3 weeks

Associated with recurring passage of diarrheal stools, fever, loss of appetite, nausea, vomiting, weight loss, and chronic weakness

Acute Diarrhea

Bacterial

Viral

Drug induced

Nutritional

Protozoal

Chronic DiarrheaTumorsDiabetesAddison’s diseaseHyperthyroidismIrritable bowel syndrome

◦ Vibrio cholera

◦ Shigella

◦ Escherichia coli

◦ Salmonella

◦ Campylobacter jejuni

◦ Yersinia enterocolitica

◦ Staphylococcus

◦ Vibrio parahemolyticus

◦ Clostridium difficile

•Rotavirus•Adenoviruses•Caliciviruses•Astroviruses•Norwalk agents and Norwalk-like viruses

•Entameba histolytica•Giardia lamblia•Cryptosporidium•Isospora

•Metabolic disease

Hyperthyroidism

Diabetes mellitus

Pancreatic insufficiency•Food allergy

Lactose intolerance•Antibiotics

• Irritable bowel syndrome

1) Laxatives

2) Antacids containing magnesium

3) Antineoplastic drugs

4) Antibiotics

a) Clindamycin

b) Tetracyclines

c) Sulfonamides

d) Any broad-spectrum antibiotic

5) Antihypertensives

a) Methyldopa

b) Angiotensin-converting enzyme inhibitors

c) Angiotensin receptor blockers

d) α-adrenergic receptor blockers

6) Cholinergic drugs

1. Neostigmine

7) Cardiac agents

1. Quinidine

2. Digoxin

8) Nonsteroidal antiinflammatory drugs

9) Misoprostol

10) Colchicine

11) Proton pump inhibitors

12) H2-receptor blockers

Most of the diarrheal agents are transmitted by the fecal-oral route

Cholera: water-borne disease; transmitted through water contaminated with feces

Some viruses (such as rotavirus) can be transmitted through air

Nosocommial transmission is possible

Shigellosis (blood dysentery) is mainly transmitted person-to-person.

Dehydration

Mild Moderate Severe

Appearance irritable,

thirsty

irritable,

very

thirsty

lethargy,

coma, or

unconscious

Anterior

Fontanelle

normal depressed markedly

depressed

Eyes normal sunken sunken

Dehydration

Mild Moderate Severe

Tongue normal dry very dry,

furred

Skin normal slow

retraction

very slow

retraction

Breathing normal rapid very rapid

Dehydration

Mild Moderate Severe

Pulse normal rapid and

low

volume

feeble or

imperceptible

Urine normal dark scanty

Weight

loss

< 5% 6 - 9% 10% or more

Stool microscopy

Dark field microscopy of stool for cholera

Stool cultures

ELISA for rotavirus

Immunoassays, bioassays or DNA probe tests to identify E. coli strains

Non-pharmacologic therapy:

Dietary management:

1. Discontinue consumption of solid foods and dairy products for 24 h (valuable in osmotic diarrhea)

2. For patients who are experiencing nausea and/or vomiting, a mild, digestible, low-residue diet should be administered for 24 hours.

3. If vomiting is present and uncontrollable with antiemetics, nothing is taken by mouth. As bowel movements decrease, a bland diet is begun.

Rehydration and maintenance of water and electrolytes

Increase fluid intake (fruit juice – contain glucose and potassium)

Oral rehydration solution (ORS). The WHO formula contains glucose, sodium, potassium, chloride and bicarbonate in an isotonic fluid.

Glucose concentrations between 80 – 120 mmol/L are needed to optimize sodium absorption in the small intestine.

Sodium concentration = 75 mmol/L (higher concentrations may cause hypernatremia)

Dose in mild/moderate diarrhea for adults: 2L/first 24 h followed by 200 ml per each loose stool

39% reduction in need for IVF

19% reduction in stool output

29% lower incidence of vomiting

Risk of hyponatremia not significant in any

type of diarrhea.

back

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Home-made ORS: Sugar or molasses (40 g) can be used as a substitute for glucose to prepare home-made ORS. Common salt (5 g) will be added to it and dissolved in one liter of clean water.

Rice-ORS: Rice powder (50 g) can replace the sugar or glucose. The amount of the other salts will remain the same. These will be dissolved in one liter of clean water to prepare rice-based ORS. Studies showed that rice-based ORS can reduce vomiting and diarrhea more in some cases compared to the conventional ORS prepared with glucose.

• Zinc has an additional modest benefit

• Reduces stool volume.

• Reduces duration of diarrhea.

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• Dose: Elemental Zinc

20 mg/day for 6months and older for 14 days

10 mg/day Between 2-6 months.

• Any of zinc salts e.g., sulphate, gluconate or

acetate may be used. back

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Indications of antidiarrheal agents:

1. Patients with mild to moderate acute diarrhea

2. Control chronic diarrhea caused by IBS or IBD

Contraindications:

Patients with bloody diarrhea, fever or systemic toxicity (risk of worsening of the underlying condition)

Discontinued in patients whose diarrhea is worsening despite therapy

Pharmacologic therapy:

Drugs used for the treatment of diarrhea include

1. Antimotility agents

2. Adsorbents

3. Antisecretory compounds

4. Antibiotics

5. Enzymes

6. Intestinal microflora.

Opioids agonists:Action in the GIT (mediated by binding to opioid

receptors)

1. Increase segmentation and a decrease propulsive movement → ↑ intestinal transit time → ↑ absorption of water and electrolyte → feces become more solid

2.Antisecretory3.↑ tone of the internal anal sphincter

4.↓ response to the stimulus of a full rectum (by their central action)

Mechanism of opioid action:

Inhibition of presynaptic cholinergic nerves in the submucosal and myenteric plexuses

Opioid agonist that has no analgesic properties in standard doses. Higher doses have central opioid actions. Used in combination with a subtherapeutic dose of atropine (to prevent abuse)

Contraindications:

1. Children below 2 y (toxicity at lower doses than adults)

2. Obstructive jaundice

Drug interactions:

1. Potentiate the effects of CNS depressants

2. Co-administration with MAO inhibitors→ hypertensive crises

Adverse effects:

1. Caused by the atropine in the preparation and include anorexia, nausea, pruritus, dizziness, and numbness of the extremities.

2. Prolonged use of high doses may cause dependence

Opioid agonist that does not cross the blood-brain barrier and has no analgesic properties and no potential for addiction

Adverse effects:

Abdominal pain and distention, constipation, dry mouth, hypersensitivity, and nausea and vomiting.

Adsorbents Coat the walls of the GI tract Bind to the causative bacteria or toxin, which

is then eliminated through the stool Examples: bismuth subsalicylate (Pepto-

Bismol), kaolin-pectin, activated charcoal, attapulgite (Kaopectate)

1. Kaolin and Pectin:Kaolin (hydrated magnesium aluminum silicate),

often combined with pectin (indigestible carbohydrate).

Mechanism of action:Adsorb bacterial toxins and fluidIndications:

Acute diarrhea (given after each loose bowel movement)

Adverse effects:Not absorbed and has no adverse effects.

2. Bismuth subsalicylate:

Insoluble complex of bismuth and salicylate

Mechanism of action:

Bismuth: antimicrobial

Salicylate: antisecretory

Adverse effects: blackening of tongue and stools

Mechanism of the anti-diarrheal action:1. It inhibits the secretion of many GIT hormones,

including gastrin, cholecystokinin, glucagon, insulin, secretin, pancreatic polypeptide, vasoactive intestinal peptide, and 5-HT3.

2. It reduces intestinal fluid secretion and pancreatic secretion.

3. It slows gastrointestinal motility and inhibits gallbladder contraction.

4. It induces direct contraction of vascular smooth muscle, leading to a reduction of portal and splanchnic blood flow.

Indications in diarrhea:

1. Secretory diarrhea due to carcinoid tumor

2. Diarrhea due to vagotomy

3. Diarrhea caused by short bowel syndrome or AIDS.

Adverse effects:1. Steatorrhea leading to fat-soluble vitamin deficiency (due to

impaired pancreatic secretion)

2. Nausea, abdominal pain, flatulence, and diarrhea due to alterations in gastrointestinal motility

3. Gall bladder sludge, gall stones or cholecystitis due to inhibition of gallbladder motility

4. Hyperglycemia

5. Bradycardia.

Anticholinergics

Decrease intestinal muscle tone and peristalsis of GI tract

Result: slowing the movement of fecal matter through the GI tract

Examples: belladonna alkaloids (Donnatal), atropine

Anticholinergics Urinary retention, hesitancy, impotence

Headache, dizziness, confusion, anxiety, drowsiness

Dry skin, rash, flushing

Blurred vision, photophobia, increased intraocular pressure

Nonpathogenic micro-organisms.

Exert a positive influence on the health or

physiology of the host.

They consist of either yeast or bacteria,

Lacto-bacillus Acidophilus

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Mechanisms:

1. Protect the intestine by competing with pathogens for attachment.

2. Strengthening tight junctions between enterocytes

3. Enhancing the mucosal immune response to pathogens.

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Indications:

1. Patients with +ve stool culture

2. Patients presented with dysentery

3. Patients with suspected exposure to bacterial infection.

• Cotrimoxazole has been recommended as the

first line drug for acute bloody diarrhea.

• High resistance of shigella to cotrimoxazole

has been reported.

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Resistance rates to cotrimoxazole exceed 30%

Cefixime 20mg/kg/day 5-7 days should be used

instead of quinolones.

If No response to cefixime in 3 days:;

Ceftriaxone 50-100mg/kg od for 2-5 days.

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Metronidazole/Tinidazole should be used when cases of acute dysentery fail to respond to second line drugs for dysentery such as cefixime or when a stool examination has confirmed trophozoites of Entamoeba hystolitica.

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Adsorbents decrease the absorption of many agents, including digoxin, clindamycin, quinidine, and hypoglycemic agents

Adsorbents cause increased bleeding time when given with anticoagulants

Antacids can decrease effects of anticholinergic antidiarrheal agents