Strongyloides stercoralis infection in the immunocompromised host.
Strongyloides stercoralis is an intestinal nematode acquired in the tropics or subtropics. Most often, it causes chronic, asymptomatic infection, but a change in immune status can increase parasite numbers, leading to hyperinfection syndrome, dissemination, and death if unrecognized. Corticosteroid use is most commonly associated with hyperinfection syndrome. Diagnosis of Strongyloides infection is based on serology and serial stool examinations for larvae. The treatment of choice for chronic, asymptomatic infection is oral ivermectin. Alternative pharmacologic agents include albendazole and thiabendazole. For hyperinfection syndrome, ivermectin remains the drug of choice, though therapy duration must be individualized with the end point being complete parasite eradication. Recurrent strongyloidiasis should prompt an evaluation for human T-cell lymphotropic virus type 1 coinfection. No test of cure is currently available, although immunoglobulin G antibody levels have been shown to decline within 6 months of successful treatment.
Ramanathan
Roshan
R
Clinical Parasitology Unit and Helminth Immunology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, 4 Center Drive, Building 4, Room B1-05, Bethesda, MD 20892, USA. ramanathanr@niaid.nih.gov
Nutman
Thomas
T