Cobalamin absorption may be abnormal in all, EXCEPT:
High-Yield Explanation
Cobalamin absorption may be abnormal in: Pernicious anemia: Due to absence of both gastric acid and intrinsic factor secretion. Chronic pancreatitis as a result of deficiency of pancreatic proteases to split the cobalamin-R binder complex. Achlorhydria or absence of another factor secreted with acid that is responsible for splitting cobalamin away from the proteins in food to which it is bound Bacterial overgrowth syndromes: leading to bacterial utilization of cobalamin (often referred to as stagnant bowel syndrome). Ileal dysfunction: due to impaired function of the mechanism of cobalamin-intrinsic factor uptake by ileal intestinal epithelial cells. Ref: Harrison, Edition-18, e37-1, e37-1t.