Strongyloides stercoralis is an intestinal nematode infecting humans. The actual prevalence of infestation with this parasite in our setting is not well established. Thus, this study was conducted to determine the age, sex and co-morbid conditions among patients with S. stercoralis infestation as well as to study the common manifestations of strongyloidiasis in our patients. Records of patients with positive S. stercoralis larvae from January 2000 to December 2012 in Hospital Universiti Sains Malaysia, Kubang Kerian, Kelantan were reviewed. Ten patients were male and two were female. Their ages ranged from 19 to 78 years old. The majority (92%) of cases, presented with intestinal symptoms and 50% with moderate to severe anaemia. Thirty percent of cases had extraintestinal manifestations such as cough, sepsis and pleural effusion. Ninety-two percent of the patients had a comorbid illness. Most patients were immunocompromised, with underlying diabetes mellitus, retroviral disease, lymphoma and steroid therapy contributing to about 58% of cases. Only 58% were treated with anti-helminthic drugs. Strongyloidiasis is present in our local setting, though the prevalence could be underestimated.
Strongyloides stercoralis is a widespread, soil-transmitted helminth affecting humans. Autoinfection occurs in S. stercoralis infection and this leads to a continuous build-up of worm burden in human host. This may lead to hyperinfection syndrome which has the potential to cause serious life-threatening disease especially in immunocompromised and immunosuppressed patients. Thus, patient with underlying risk factors should be suspicious of having this infection as severe strongyloidiasis carries a high mortality rate if the diagnosis is delayed. Here, we report a case of S. stercoralis hyperinfection in a diabetic patient.
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.
Strongyloides stercoralis infection can persist in the host for several decades, and patients with cancer and other clinical conditions who are exposed to immunosuppressive therapy are at risk of developing hyperinfection.