The incidence of cryptosporidiosis was studied in 560 cancer patients
presenting with symptoms of diarrhoea. Cryptosporidium oocysts were de
tected in the stool specimens by modified acid fast staining. Blood wa
s examined for HIV antibodies from patients whose stool specimens were
positive for Cryptosporidium oocysts. Oocysts were detected in 7 of t
he 560 (1.3%) patients who were receiving chemotherapy and had diarrho
ea; in five of them the symptoms were acute, while two patients had ch
ronic diarrhoea. Of these seven patients, five had cancer of haemopoet
ic system, one had cancer of cervix and one had uterine sarcoma. None
of the patients positive for oocysts were positive for HIV antibodies,
ruling out the possibility of an opportunistic infection due to HIV i
nfection.