Low prevalence of intestinal cryptosporidiosis among immunocompetent and immunocompromised patients with and without diarrhoea in southern Germany.

1160 stool specimens, from 160 severely immunocompromised patients, from 70 adults and 180 children with acute diarrhoea and from 60 controls without diarrhoea and without evidence of immunocompromising underlying disorders, were examined for Cryptosporidium excretion. Only two children (1.1%) (one with previous contact to a straying cat and to lambs, the other without known risk) had documented intestinal cryptosporidiosis, whereas none of the symptomatic adults, immunocompromised patients or controls were found to be positive for Cryptosporidium fecal excretion. Other potential protozoal enteric pathogens among immunocompromised patients were only found in seven of 25 patients with HIV infection. We conclude that sporadic intestinal cryptosporidiosis in Southern Germany is a rare disease in humans even of younger age, but should be included in the differential diagnosis of diarrhoea in immunocompetent and immunocompromised patients.