Clinical, endoscopic, and histologic spectrum of nonsteroidal anti-inflammatory drug-induced lesions in the colon

PURPOSE: It has became increasingly clear that nonsteroidal anti-inflammato ry drugs may cause damage not only to the upper gastrointestinal tract but also to the small and large intestine. Although the colon may be readily in vestigated by endoscopy, drug-induced lesions are not well known, probably because they are considered to occur only rarely. In the present study we d escribe endoscopic, histo logic, and gross characteristics of nonsteroidal anti-inflammatory drug-induced colonic damage. Furthermore, patho genetic m echanisms and therapeutic options are discussed. METHODS: The histories of all patients diagnosed as having nonsteroidal anti-inflammatory drug coliti s during the last two years at the department of gastroenterology or the de partment of pathology at our hospital were reviewed. Endoscopic, histologic , and gross pathologic findings were systematically recorded. In addition, data on duration and type of nonsteroidal anti-inflammatory drug intake and time from onset of symptoms to diagnosis were collected. Therapy and outco me of our patients, if available, are reported. RESULTS: During the study p eriod 11 patients were diagnosed as having nonsteroidal anti-inflammatory d rug colitis. Most patients presented with diarrhea with or without blood lo ss and complained about diffuse abdominal pain. Endoscopy revealed flat ulc ers in the entire colon being more severe in the right colon in the three c ases with acute onset of diarrhea. In four cases concentric "diaphragm-like " strictures were seen, all located in the right colon. In the remainder en doscopy showed nonspecific erosions and was normal in one patient. Histolog y revealed findings similar to ischemic colitis. Additionally, in two cases collagenous colitis was found. Diclofenac slow release was the most common ly involved drug. The median time from onset of symptoms to diagnosis was 1 .8 (range, 0-11.5) years. CONCLUSIONS: Nonsteroidal anti-inflammatory drug colitis is a clinically significant disease, which may present with diarrhe a, anemia, and nonspecific abdominal complaints. Careful history taking, to gether with awareness of endoscopic and histologic findings, allows a timel y diagnosis of this disease.