DIARRHEA

Presented by Ezza Nur Adzliyanni Binti Azali082013100005

DIARRHEA

• Diarrhea is defined as passage of abnormally liquid or unformed stools at an increased frequency.

• Stool weight >200 g/d.• It is further defined

i. Acute if <2 weeksii. Persistent if 2–4 weeks iii. Chronic if >4 weeks

PATHOPHYSIOLOGY

Osmotic Diarrhea• Absorption of water in the intestine is

dependent on adequate absorption of solutes.

i. Ingestion of a poorly absorbed substrate: ii. Malabsorption

Excessive amounts of solutes are

retained in the intestinal lumen

Water will not be absorbed

Secretory Diarrhea

• Diarrhea occurs when secretion of water into the intestinal lumen exceeds absorption.

ACUTE DIARRHEA

• Diarrhea that comes on suddenly and goes away over a period of a couple of weeks.

• >90% caused by infectious agents.

• Remaining 10%i. Medicationsii. Toxic ingestionsiii. Ischemia

A. Infectious Agents

• Feco-oral transmission• Systemic manifestations

• Five high-risk groups

Reiter's syndromeArthritis

UrethritisConjuctivitis

Salmonella, Campylobacter, Shigella, and Yersinia.

Hemolytic-uremic syndrome

- High mortality rate

Enterohemorrhagic E. coli and Shigella

Others:Viral hepatitis

ListerosisToxic shock syndrome

•Enterotoxigenic or Enteroaggregative E.coli •Campylobacter•Shigella•Giardia

Travelers

• Chicken : Salmonella, Shigella, Campylobacter

• Undercooked hamburger : Enterohemorrhagic E. coli•Fried rice or reheated food : Bacillus cereus•Mayonnaise or creams :

Staph.aureus/Salmonella•Eggs : Salmonella•Uncooked foods : Listeria•Seafood (esp raw) : Vibrio sp, Salmonella,

Acute hepatitis A

Consumers of certain

foods

•Primary immunodeficiency : IgA deficiency, common variable hypogammaglobulinemia, chronic granulomatous disease

•Secondary immunodeficiency : AIDS, pharmacologic suppression

Immunodeficient persons

•Shigella•Giardia•CryptosporidiumDay care

attendees and their family members

• C.difficile Institutionalized persons

CLINICAL FEATURES

Pathogen Incubation PeriodBacillus cereusStaph.aureus

1-8 hr

Clostridium perfringens 8-24 hrVibrio choleraeEnterotoxigenic Escherichia coliKlebsiella pneumoniaeAeromonas species

8–72 h

Enteropathogenic E.coliEnteroadherent E. coliGiardia

1-8 days

C. difficile 1–3 dHemorrhagic E. coli 12–72 hRotavirus and norovirus 1–3 dSalmonellaCampylobacter Aeromonas speciesVibrio parahaemolyticus Yersinia

12 h–11 d

B. Medications

• Antibiotics• Anti hypertensives• Antidepressants• Antacids• Bronchodilators• Chemotherapeutic agents• Cardiac antidysrhythmics• NSAIDs• Laxatives

C. Ischemic colitis

D. Toxins

i. Organophosphate insecticidesii. Amanita and other mushroomsiii. Arsenic

Acute lower abdominal pain preceding watery then bloody diarrhea

Acute inflammatory changes in the sigmoid or left colon while sparing the rectum.

APPROACH TO PATIENT WITH ACUTE DIARRHEA

• Mild and self-limited.

• Indications for evaluation include :

Abdominal pain (severe) in patients >50 years

Antibiotic use (recent)

Bloody stools (grossly)

New Community outbreaks

Duration >48 h without improvement

Profuse diarrhea with Dehydration

Elderly (>70 years)

Fever 38.5°C (101°F) Immunocompromised patients

INVESTIGATIONS

• Microbiologic analysis of the stool :

i. Cultures for bacterial and viral pathogens.ii. Direct inspection for ova and parasites.iii. Immunoassays for certain

- Bacterial toxins (C. difficile)- Viral antigens (rotavirus)- Protozoal antigens (Giardia, E. histolytica)

• Flexible sigmoidoscopy with biopsies and upper endoscopy with duodenal aspirates and biopsies may be indicated.

• Structural examination by sigmoidoscopy, colonoscopy or abdominal CT scanning

i. To exclude IBDii. Initial approach in patients with suspectednon-infectious acute diarrhea.

MANAGEMENT

•Mild case : Fluid alone•Severe case : Oral sugar-electrolytes solutionsFluid and

electrolyte replacement

•Dehydrated patients, especially infants and the elderly.IV rehydration

•Moderately severe non febrile and non bloody diarrhea.

•To control symptoms.•Avoided with febrile dysentery, which may be

exacerbated or prolonged by them.

Antimotility and Antisecretory

agents

•Reduce severity and duration of diarrhea.•Treat empirically without diagnostic evaluation.

Quinolone (500 mg bid for 3–5 d)Metronidazole (250 mg qid for 7 d)

•If travelling to high-risk countries•Immunocompromised•Hemochromatosis•IBD

Antibiotic prophylaxis

**Antibiotic is indicated whether or not causative org is discovered in patients who arei. Immunocompromisedii. Have mechanical heart valve or recent vascular graftsiii. Elderly

THANK YOU