Detection of Strongyloides stercoralis infection among cancer patients in a major hospital in Kelantan, Malaysia

INTRODUCTION Strongyloidiasis is one of the most commonly neglected but clinically important parasitic infections worldwide, especially among immunocompromised patients. Evidence of infection among immunocompromised patients in Malaysia is, however, lacking. In this study, microscopy, real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assays (ELISAs) were used to detect Strongyloides stercoralis (S. stercoralis) infection among cancer patients in a Malaysian hospital. METHODS A total of 192 stool and serum samples were collected from cancer patients who were receiving chemotherapy with or without steroid treatment at a hospital in northeastern Malaysia. Stool samples were examined for S. stercoralis using parasitological methods and real-time PCR. Serology by ELISA was performed to detect parasite-specific immunoglobulin G (IgG), IgG4 and immunoglobulin E (IgE) antibodies. For comparison, IgG4-and IgG-ELISAs were also performed on the sera of 150 healthy individuals from the same area. RESULTS Of the 192 samples examined, 1 (0.5%) sample was positive for S. stercoralis by microscopy, 3 (1.6%) by real-time PCR, 8 (4.2%) by IgG-ELISA, 6 (3.1%) by IgG4-ELISA, and none was positive by IgE-ELISA. In comparison, healthy blood donors had significantly lower prevalence of parasite-specific IgG (2.67%, p <0.05) and IgG4 (2.67%, p <0.05) responses. CONCLUSION This study showed that laboratory testing may be considered as a diagnostic investigation for S. stercoralis among immunocompromised cancer patients.