Cytologic detection of Strongyloides stercoralis in a 55-year-old Hispanic man with routine rectal/anal pap smear.

The anal-rectal cytology is introduced recently to evaluate human-papillomavirus related cellular changes in the cells of anal canal. It is especially useful in high risk patients such as HIV patients. Very few reports were published regarding cytomorphological findings in anal cytology. Strongyloides stercoralis is an enteric helminthic parasite with particular significance in immunocompromised patients. The infection is asymptomatic or manifests as mild gastrointestinal symptoms in normal hosts. The infection can be devastating in immunocompromised persons, and carries a high mortality rate. The presence of S. stercoralis larva in anal-rectal pap smears is rare. We report a case in a routine anal-rectal Pap smear with Strongyloides, and discuss the clinical significance and life cycle of S. stercoralis.