Colonic malakoplakia in a cardiac transplant recipient

Abstract

Malakoplakia is a rare inflammatory condition which is usually seen in the urogenital tract and less commonly in the gastrointestinal tract. Gastrointestinal malakoplakia may be associated with organ transplantation. There are previously only three reported cases of malakoplakia in cardiac transplant recipient. We report a case of colonic malakoplakia in a 38-year-old male who underwent cardiac transplantation for dilated cardiomyopathy 4 years previously and who had been on tacrolimus and mycophenolate. The patient presented with history of diarrhea associated with fecal incontinence for the past 6 months. Ileocolonoscopic examination was within normal limits. A rectal biopsy was done to exclude microscopic pathology. Microscopy revealed expansion of the lamina propria by histiocytes admixed with a few lymphocytes. The histiocytes showed granular eosinophilic cytoplasm with intracytoplasmic presence of Michaelis-Gutmann bodies, rounded basophilic laminated structures having central core with a targetoid appearance. These stained positively for Von kossa stain for calcium and were diagnostic for malakoplakia. Although rare, malakoplakia may be associated with chronic diarrhea even if there are no macroscopic lesions seen during colonoscopy. The patient's symptoms resolved with long-term ciprofloxacin therapy.