Recurrent pneumonia: Can it be parasite induced?

Abstract

Strongyloides stercoralis is an intestinal nematode acquired primarily in the tropics, estimated to infect approximately 100 million people worldwide. Strongyloidiasis can be asymptomatic in many individuals or present in a variety of ways including acute infection, chronic infection, hyperinfection, and disseminated infection. We present a case where recurrent pneumonia was being evaluated and later found to be due to strongyloides hyperinfection syndrome and successfully treated with ivermectin. A 74-year-old female background of seasonal bronchitis, recurrent lower respiratory tract infections presented to us with Gram-negative bronchopneumonia which was treated but recurred after a few days. Investigations were ongoing for fungal infections when we picked up the S. stercoralis hyperinfection. In tropical regions, the regional prevalence of strongyloides infection may exceed 25%. Strongyloides hyperinfection describes the syndrome of accelerated autoinfection, generally the result of an alteration in immune status. Hyperinfection syndrome is estimated to happen in 1-2.5% of the patients with strongyloidiasis. Hyperinfections are often complicated, and gut flora gain access to extraintestinal sites, presumably through ulcers induced by the filariform larvae or by virtue of being carried on the surface or in the intestinal tract of the larvae themselves. Our patient did not have symptoms of strongyloides or reasons for immunosuppression. She only could have been immunosuppressed due to age or possible steroid use for seasonal bronchitis. We want to point out that strongyloides hyperinfection is a possible cause of recurrent Gram-negative pneumonia and sepsis. Parasitic infection screening must be done in all patients in our country who are admitted with severe sepsis.