infectious diseases
Strongyloidiasis
Introduction
Strongyloidiasis is infection withStrongyloides stercoralis. Findings include abdominal pain and diarrhea, rash, pulmonary symptoms (including cough and wheezing), and eosinophilia. Diagnosis is by finding larvae in stool or small-bowel contents or occasionally in sputum or by detection of antibodies in blood. Treatment is withivermectinoralbendazole. (See also Approach to Parasitic Infections .) Strongyloidiasis is one of the major soil-transmitted parasitic diseases. An estimated 30 to100 million people are infected worldwide. Strongyloidiasis is endemic throughout the tropics and subtropics, including rural areas of the southern United States, at sites where bare skin is exposed to infective larvae in soil contaminated by human feces.S. stercoralishas the unique ability to develop to adulthood in soil as well as the human intestine. Furthermore, unlike other soil-transmitted roundworms,S. stercoralisis capable of autoinfection, which can result in chronic disease lasting decades, or cause overwhelming hyperinfection in people taking corticosteroids or other immunosuppressive drugs or who have impaired Th2 type cell-mediated immunity, particularly those infected with the human T-lymphotropic virus 1 (HTLV-1). During hyperinfection, large numbers of larvae gain access to the bloodstream, lungs, central nervous system, and other organs. Polymicrobial bacteremia and meningitis can occur due to disruption of intestinal mucosa and the presence of bacteria on the surface of invading larvae. infections have occurred in recipients of solid organ transplants, both in those with pre-existant subclinical infection and in those who have received organs from asymptomatic but infected donors ( General reference ). Strongyloides fülleborni, which infects chimpanzees and baboons, can cause limited infections in humans. 