1. MALABSORPTION BGD 2: Chronic Diarrhea De Vera, Jestha Marie Bernadette P. Dela Cruz, Ciara Mae Dela Cruz, Fatima C.

2. Malabsorption Defective absorption of fats, fat-soluble and other vitamins, proteins, carbohydrates, electrolytes and minerals, and water Most common clinical presentation is CHRONIC DIARRHEA Hallmark: Steatorrhea Cause excessive fecal excretion and produce nutritional deficiencies and GI symptoms

3. Malabsorption occurs when any of these digestive functions is impaired: 1.INTRALUMINAL DIGESTION – Proteins, carbohydrates and fats are broken-down into assimilable forms. 2.TERMINAL DIGESTION – Hydrolysis of carbohydrates and peptides in the brush border of the small intestinal mucosa 3.TRANSEPITHELIAL TRANSPORT – Nutrients, fluid & electrolytes are transported across the epithelium of the small intestine for delivery to the intestinal vasculature – Absorbed fatty acids  triglycerides + cholesterol  chylomicrons  intestinal lymphatic system

4. COMMON CAUSES OF MALABSORPTION MechanismSpecific Disease MaldigestionChronic pancreatitis, cystic fibrosis, pancreatic carcinoma Bile Salt deficiencyCirrhosis, cholestasis, bacterial overgrowth, impaired ileal reabsorption, bile salt binders Inadequate Absorptive surfaceMassive intestinal resection, gastrocolic fistula, jejunoileal bypass Lymphatic obstructionLymphoma, Whipple’s disease, intestinal lymphangiectasia Vascular diseaseConstrictive pericarditis, right-sided heart failure, mesenteric arterial or venous insufficiency Mucosal diseaseInfection (esp.Giardia, Whipple’s disease, tropical sprue), Inflammatory diseases, radiation enteritis, eosinophilic enteritis, ulcerative jejunitis, mastocytosis, biochemical abnormalities

5. PATIENTGIARDIASIS WHIPPLE’S DISEASE TROPICAL SPRUE Epidemiology From Bangladesh after a year of missionary work Institutional settings with poor fecal hygiene In campers and travelers extremely rare, most cases among Caucasians Tropical areas including southern India, Philippines and several Caribbean islands diarrhea Duration3-5x/day for the past month>1 week Occur within days or weeks after infection & persists if untreated Stool charac- teristics Loose Mushy & mucoid With streaks of blood Steatorrhea Blood or mucus is rare Steatorrhea Other GI symptoms Crampy, hypogastric pain Rectal tenderness Abdominal pain, bloating, belching, flatus, nausea and vomiting last >1 week Abdominal pain, Occult GI bleeding (80%) but frank hematochezia is uncommon Constitutional symptoms and other manifestations Low grade fever, pale palpebral conjunctiva Anorexia, fatigue, malaise, and weight loss; urticaria, bronchospasm, reactive arthritis Fever, weight loss, migratory large-joint arthropathy, and as well as ophthalmologic and CNS symptoms Fever, malaise, weight loss & nutritional deficiencies including folate & cobalamin

6. Giardiasis major diarrheal disease worldwide Ingestion of as few as 10 Giardia lamblia cysts Postulated mechanisms – damage to the endothelial brush border – Loss of brush border enzyme activity

7. Whipple’s Disease extremely rare worldwide; mostly from North America and western Europe More common among white males; mid-aged & elderly systemic disease most likely caused by a gram-positive bacterium, Tropheryma whippelii wasting illness (arthralgias, arthritis, fever, and diarrhea) malabsorption is believed to be secondary to the disruption of normal villous function due to infiltration of the lamina propria of the small bowel

8. Tropical Sprue affects 5–10% of the population in some tropical areas incidence have decreased substantially during the past two decades etiology and pathogenesis of tropical sprue are uncertain not evenly distributed in all tropical areas – southern India, the Philippines, and several Caribbean islands (e.g., Puerto Rico, Haiti) – rarely observed in Africa, Jamaica, or Southeast Asia An occasional individual will not develop symptoms of tropical sprue until long after having left an endemic area Mild alteration of villous architecture  mild decreases in absorptive function

9. Work-ups Timed (72 h) quantitative stool collection Fat malabsorption: >6g in 24 h Complete blood count Small intestinal mucosal biopsy Short or absent villi Mononuclear infiltrate Epithelial cell damage Hypertrophy of crypts

10. Treatment Broad-spectrum antibiotics Tetracycline for up to 6 months Folic Acid