Immunobiology of strongyloidiasis.

Strongyloides stercoralis causes a usually silent infection that, under certain conditions of altered host-parasite balance, may become a severe, often fatal, disseminated disease. Patients, as well as experimental animals, develop specific humoral and cellular responses to the tissue-invading stage of the parasite, the filariform larvae. These responses, however, while potentially useful for diagnostic purposes, appear to be of little importance in determining the course of the disease. It is suggested that local intestinal factors may play a central role in the control of autoinfection. Until these questions are resolved and more accurate diagnostic methods are devised, preventive therapy in all patients from endemic areas that must undergo immunosuppressive therapy is advised.