The histopathology of 103 consecutive colonoscopy biopsies from 82 symptomatic patients with acquired immunodeficiency syndrome - Original and look-back diagnoses

Objective.-To compare the primary diagnoses assigned by general surgical pa thologists on a series of 103 consecutive colon biopsies from individuals i nfected with human immunodeficiency virus (HIV) with diagnoses rendered by a pathologist with extensive experience in gastrointestinal pathology in HI V/acquired immunodeficiency syndrome. Design.-New sections were cut from paraffin blocks of 103 consecutive colon biopsies taken during colonoscopies of 82 different HIV-infected patients; all new sections were stained with hematoxylin-eosin. These individuals ei ther had negative stool studies or had failed to respond to therapy and had chronic large bowel symptoms, such as frequent small volume-type diarrhea, tenesmus, and/or bright red blood per rectum. Immunohistochemistry for cyt omegalovirus (CMV) was performed on 18 of 22 specimens originally diagnosed with CMV colitis. Results.-The initial study yielded 70 (68%) negative or nonspecific diagnos es, 22 (21%) cases of CMV colitis, 5 (5%) Cryptosporidium, diagnoses, 2 cas es each of adenomatous polyps and Kaposi sarcoma, and I case each of spiroc hetosis and squamous cell carcinoma of the anorectum. Review of the recuts yielded 64 (62%) negative or nonspecific diagnoses, 12 (12%) new adenovirus infections (3 combined with CMV), and I I (11%) lone CMV infections. Three attaching and effacing bacterial infections were diagnosed, I with adenovi rus coinfection. A total of 4 spirochetosis cases were found on review. Sev en (7%) of the biopsies showed at least 1 coinfection. Nine biopsies had fe atures suggestive of inflammatory bowel disease. Conclusions.-Colonoscopy with biopsy after negative stool studies or failur e to respond to therapy yielded a high proportion of negative or nonspecifi c diagnoses. Adenovirus and enteropathogenic bacterial infections had been totally overlooked on initial examination. It takes particular experience t o evaluate gastrointestinal biopsies from HIV-infected patients.