Small Bowel Disorders & Malabsorption

By completing this question set, you will be able to apply the malabsorption anatomical localization framework to map nutrient deficiency patterns onto specific small bowel disease sites. You will diagnose celiac disease using the correct serologic algorithm (total IgA first), interpret the four Marsh histologic findings, manage dysplasia complications, and recognize dermatitis herpetiformis as a cutaneous manifestation. You will distinguish Whipple's disease from other malabsorption syndromes by its PAS-positive macrophage histology and neurologic involvement. You will explain why SIBO causes B12 deficiency but elevated folate. You will differentiate tropical sprue from celiac disease by etiology and treatment. You will apply the short bowel syndrome segment-dependent complication framework and identify when cholestyramine is contraindicated. You will apply the Meckel's diverticulum rule of 2s and identify the appropriate diagnostic test. You will explain why carcinoid syndrome requires hepatic metastases, identify the right-sided cardiac predilection, and interpret a 24-hr urine 5-HIAA in context.