Strongyloides stercoralis: a cause of morbidity and mortality for indigenous people in Central Australia

Abstract

Strongyloides stercoralis may cause a complicated infection in immunocompromised patients, which has a high case fatality rate. Death generally results from sepsis with enteric pathogens. Globally, infection with the human T-cell lymphotropic virus type 1 (HTLV-1) is a major risk factor for this syndrome. Both S. stercoralis and HTLV-1 are endemic to Central Australia. The aim of the study was to determine whether complicated strongyloidiasis occurs in association with HTLV-1 infection in Central Australia. A retrospective audit of all cases of complicated strongyloidiasis presenting to Alice Springs Hospital between January 2000 and December 2006 was carried out. Diagnosis was defined as definite or probable according to whether diagnosis was made by faecal studies or serology respectively. The medical records, investigations and outcomes of patients who met predetermined criteria for a diagnosis of complicated strongyloidiasis were reviewed. Eighteen indigenous patients met the criteria for complicated strongyloidiasis (definite 9, probable 9). Seven of 11 patients tested were HTLV-1 seropositive. At diagnosis, no treatment was documented for nine patients (definite 4, probable 5), three received a single dose of ivermectin and one a single dose of albendazole. Fifteen patients (83%) died because of sepsis (definite 7, probable 8). Pathogens isolated and their foci of infection included Klebsiella pneumoniae pneumonia (4), bloodstream infection with Enterococcus spp. (2), K. pneumoniae peritonitis (1) and streptococcal meningitis (1). Complicated strongyloidiasis occurs in association with HTLV-1 infection in central Australia. This finding has significant implications for the management of S. stercoralis in the region.