Hyperinfection syndrome in strongyloidiasis: report of two cases

Hyperinfection in strongyloidiasis has been associated with corticosteroid treatment. Other immunodepressive conditions also seem to facilitate the state of hyperinfection. The etiologic diagnosis of this parasitosis can be difficult to reach and a positive urine microscopy is unusual. We report two patients under corticosteroid therapy with disseminated strongyloidiasis; both had eosinophilia. The first patient, followed for 8 years for autoimmune hemolytic anemia, recently developed abdominal symptoms. A colonoscopy was performed 1 month before admission and the biopsy was thought to show nonspecific changes. At admission, few larvae of Strongyloides stercoralis were disclosed by urine microscopy, and a review of the colonic biopsy uncovered a few larvae of Strongyloides. The patient received anti-helmintic therapy with a dramatic improvement. The second patient, under treatment for lupus erythematosus for 3 years, was admitted with pulmonary symptoms and during admission developed massive gastrointestinal bleeding. Disseminated strongyloidiasis was discovered only at autopsy. The low suspicion index for strongyloidiasis resulted in delaying the etiologic diagnosis in one patient and in failing to diagnose the disease in the other. The morphologic features of the parasite in the two cases are presented with emphasis on the difficulties of recognizing the larvae in the intestinal biopsy.