Diarrhea_Harrison_Presentation.pptx for diarrhea

Nothing just diarrhea

1. Diarrhea: A Comprehensive Overview Based on Harrison’s Principles of Internal Medicine

2. Introduction Diarrhea is defined as an increase in stool frequency (≥3 per day) with decreased consistency. It can be classified based on duration, pathophysiology, and etiology. Effective management requires understanding the underlying cause and maintaining fluid-electrolyte balance.

3. Classification of Diarrhea - Acute Diarrhea (<14 days): Mostly infectious or drug-induced. - Persistent Diarrhea (14-30 days): Prolonged infections or post-infectious changes. - Chronic Diarrhea (>30 days): Causes include secretory, osmotic, inflammatory, or malabsorptive disorders.

4. Causes of Diarrhea - Infectious: Bacteria (E. coli, Salmonella), Viruses (Rotavirus), Parasites (Giardia). - Inflammatory: Crohn’s disease, Ulcerative colitis. - Malabsorptive: Celiac disease, Chronic pancreatitis, Lactose intolerance. - Endocrine: Hyperthyroidism, Addison’s disease, Zollinger-Ellison syndrome. - Drug-Induced: Laxatives, NSAIDs, Antibiotics (C. difficile colitis).

5. Pathophysiology of Diarrhea - Secretory: Persistent even with fasting (cholera, VIPoma). - Osmotic: Due to poorly absorbed solutes (lactose intolerance, sorbitol). - Exudative: Associated with mucosal inflammation (IBD, infections). - Motility Disorders: Increased transit time (IBS, diabetes).

6. Clinical Features - Mild: Increased stool frequency, urgency, bloating. - Severe: Bloody diarrhea, dehydration, weight loss. - Signs of Dehydration: Dry mouth, sunken eyes, hypotension. - Electrolyte Imbalances: Hyponatremia, Hypokalemia, Metabolic acidosis.

7. Diagnostic Approach - History & Physical Examination: Stool characteristics, travel history. - Laboratory Tests: CBC, electrolytes, renal function, stool analysis. - Microbiologic Tests: Stool culture, C. difficile toxin, viral PCR. - Imaging: Abdominal CT for suspected IBD or malignancy. - Endoscopy: Colonoscopy for chronic or bloody diarrhea.

8. Management of Acute Diarrhea - Fluid Replacement: ORS for mild cases, IV fluids for severe dehydration. - Antibiotics: Azithromycin for traveler's diarrhea, Metronidazole for C. difficile. - Symptomatic Treatment: Loperamide for non-bloody diarrhea, probiotics. - Dietary Advice: BRAT diet (bananas, rice, applesauce, toast).

9. Management of Chronic Diarrhea - Identify underlying cause: Lactose-free diet, gluten-free diet. - Medications: Loperamide for symptomatic relief, cholestyramine for bile acid diarrhea. - Nutritional Support: Correct vitamin deficiencies (B12, D, A, E, K).

10. Prevention Strategies - Hygiene: Handwashing, clean drinking water. - Food Safety: Proper cooking, avoiding raw seafood. - Vaccination: Rotavirus vaccine in children, cholera vaccine in endemic regions. - Antibiotic Stewardship: Avoid unnecessary antibiotic use.

11. Conclusion - Acute diarrhea is often self-limiting but requires hydration management. - Chronic diarrhea needs thorough evaluation to identify treatable causes. - Prevention through hygiene, safe food practices, and vaccines is key.