Gastric cryptosporidiosis: correlation between intensity of infection and histological alterations.

Abstract

A retrospective study was carried out to determine the histopathological alterations of the gastric mucosa associated with the presence of Cryptosporidium parasites in the stomach. Gastric biopsies from eight patients with AIDS and cryptosporidiosis were reviewed. Most individuals were males (7/8, mean age 34.7 years) intravenous drug users (6/8), with very low peripheral blood CD4 lymphocyte counts (< 150/mm3; mean 56/mm3). Endoscopic examination showed no significant mucosal abnormalities in half of the individuals; inflammation was observed in the other four individuals and was associated with erosions in two cases. The lesions observed (reactive changes, oedema, erosions, etc.) are not pathognomonic, since they are seen in most common acute and chronic gastrititis of various aetiologies (toxic, infectious, mechanical). The histological examination showed Cryptosporidium parasites in the antrum-pylorus of all examined persons, whereas only two of them had parasites in the corpus. Modifications of histological features consisted mostly of hyperplastic reactive changes of the gland epithelial and inflammation in the connective tissue of the lamina propria. No clear correlation was found between endoscopy and histological findings, whereas a close correlation between intensity of the infection and degree of histological alterations was observed. These findings suggest that, in individuals with AIDS, cryptosporidiosis and severe immunodepression, upper endoscopy with random gastric biopsies should be performed, even in the absence of endoscopically appreciable lesions. The diagnosis of gastric cryptosporidiosis has to rely on histological findings, and pathologists must be aware of the fact that Cryptosporidium parasites are mainly found in areas showing reactive hyperplasia.