A rare case of chronic diarrhea.

Abstract

noscopy showed diffuse mucosal edema through the entire colon, with multiple reddish erosions and contact bleeding (Fig. A). On colonoscopic biopsy, homogenous amyloid deposits were seen in the parenchyma and vessels (Fig. B, H&E, ×200), and Congo red staining for the amyloid, coupled with polarized light, demonstrated the characteristic apple-green birefringence (Fig. C, Congo red, ×400). Chest radiography revealed mild cardiomegaly and pulmonary edema (Fig. D). In urine immunofixation, electrophoresis showed a prominent M-peak on the lambda light chain. The peripheral blood smear finding was only thrombocytosis, and bone marrow aspiration showed 8−10% plasma cells of all nucleated cells without Congo red positivity. What is the diagnosis? A Rare Case of Chronic Diarrhea