Intestinal Strongyloidiasis

Abstract

Significant advances have occurred in our understanding of the biology, immunology, and immunopathology of the usually asymptomatic human infection by the intestinal parasite, Strongyloides stercoralis. Factors that increase the risk for the occurrence of symptomatic intestinal hyperinfection and/or often-fatal disseminated strongyloidiasis have been better defined. The pathophysiology underlying these risk factors, whether disease-related or iatrogenically induced, is a compromised immune system leading to dysfunction of TH-2 helper cells. These specialized lymphocytes are central to maintaining the delicate balance that exists between the infected human host and the stabilized parasite. Recognition of risk factors that impair the function of TH-2 lymphocytes is essential to heightening the index of clinical suspicion enhancing earlier, accurate diagnosis, and the introduction of appropriate therapy. This review summarizes what is understood about infection by S. stercoralis; its focus will be on the epidemiology, diagnosis, clinical presentation patterns in the immunocompetent and immunocompromised human hosts, and recommended treatment regimens.

Strongyloides stercoralis hyperinfection - a dreaded but still missed diagnosis

“…26,27 Corticosteroids increase apoptosis of lymphocytes, reduce circulating numbers of eosinophils and ultimately decrease the mast cell response to S. stercoralis antigens in the intestines. 28 The first blood cell count of this patient showed a low eosinophil count, which, unfortunately, may have lowered the suspicion of the helminthic hyperinfection. This low eosinophil count in the presence of the helminthic infection may have resulted from chronic corticoid usage.…”

“…14,16,17 Gram-negative bacteria and other bowel flora may gain access to the bloodstream through ulcers in the bowel or by transport on the surface of migrating larvae. 21,28,29 The severe and potentially fatal infections caused by S. stercoralis are known as hyperinfection syndrome and disseminated strongyloidiasis, 14 rarely observed in immunocompetent individuals. The hyperinfection syndrome is characterized by an acceleration of life cycle and hyperinfection, and by an increased parasite burden within the sites of the nematode cycle.…”

Overview of Strongyloidiasis: A Neglected Tropical Disease

“…Though the acute initial manifestations are not well described (Ly et al, 2003) the following symptoms are noted in some human infections like urticarial rash at the site of entry of the filariform larvae mostly in the legs (Concha et al, 2005;Keiser et al, 2005;Ly et al, 2003) cough and tracheal irritation incurring bronchitis from migration of the larvae through the lungs (Keiser et al, 2005) abdominal cramping with bloating, watery diarrhea and sometimes constipation due to lodging of the larvae and maturation into adult females in the small intestine of the host (Keiser et al, 2005;Muiz, 2003;Sudarshi et al, 2003;Berk et al, 1987) . In fact, the most common complaint noted was abdominal bloating (Sudarshi et al, 2003;Berk et al, 1987).…”

“…The or dissemination can occur, asymptomatic strongyloidiasis is the most common form of the disease (Concha et al, 2005;Keiser et al, 2005) and often fatal consequences if not treated adequately (Ericsson et al, 2001). The various clinical manifestations are shown in Table 2.…”

“…The parasite is mostly confined to the tropics and subtropics ). The infection is more prevalent in the Appalachian region mainly rural Tennessee (Concha et al, 2005). S. stercoralis is a soil dwelling nematode and may take one of the two cycles depending on the prevalent conditions and turns parasitic in adverse conditions (Keiser and Nutman, 2004).…”