title: Clozapine-induced microscopic colitis: a case report and review of the literature.
abstract: Both diarrhea and colitis associated with clozapine have been reported. In this article, the authors present a case of clozapine-induced microscopic colitis (MC)-the first reported in the literature. The definitive diagnosis was suggested on colon biopsy, which showed an intraepithelial lymphocytosis (with >20 lymphocytes for every 100 epithelial cells) more striking in the surface epithelium than in the crypts. In addition, there were a mixed inflammatory infiltrate in the lamina propria (with lymphocytes predominating over eosinophils and neutrophils), an architecturally preserved colonic mucosa (particularly in the crypts), and a subepithelial collagen band normally thickened (<10 microm). Clozapine was thought to be the culprit and discontinued. After some days, the patient gradually improved. Diarrhea and spiking fever disappeared within 72 hours. Multiple colon biopsies taken after 7 days from the discontinuation of the clozapine revealed no abnormal histological findings. It is important to clarify the issue of clozapine-induced MC because MC may require the use of expensive or potentially toxic treatments and can occasionally be life-threatening (eg, hypokalemia). Thus, any case of MC that can be cured by withdrawal of the clozapine must be investigated and identified.
authors.affiliation: Guastalla Psychiatric Operative Unit, Reggio Emilia Mental Health Department, Via Salvo D'Acquisto n. 7, Guastalla, Italy. anolino@yahoo.it
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Pelizza
authors.forename: Micaela
authors.initials: M
authors.lastname: Melegari
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects / Q000627:therapeutic use; D001706:Biopsy; D003024:Clozapine / Q000009:adverse effects* / Q000627:therapeutic use; D046728:Colitis, Microscopic / Q000139:chemically induced* / Q000175:diagnosis; D003106:Colon / Q000187:drug effects / Q000473:pathology; D006801:Humans; D008218:Lymphocytosis / Q000139:chemically induced / Q000175:diagnosis; D008297:Male; D012563:Schizophrenia, Paranoid / Q000175:diagnosis / Q000188:drug therapy; D028761:Withholding Treatment
chemical_list: D014150:Antipsychotic Agents; D003024:Clozapine