Clinical presentation and diagnostic sensitivity of laboratory tests for Strongyloides stercoralis in travellers compared with immigrants in a non‐endemic country

Abstract

Summaryobjectives To assess whether the clinical and laboratory methods for diagnosing Strongyloides stercoralis infection in non-endemic countries is different between those who are chronically exposed and those who travel.methods Analysis of laboratory and clinical data from 204 patients having S. stercoralis infection at the Hospital for Tropical Diseases, London.results Sixty-four travellers and 128 immigrants from endemic countries had laboratory-proven strongyloides. In those with microscopically proven disease, serology was 73% sensitive in travellers and 98% sensitive in immigrants (P < 0.001). There was no difference in the eosinophil count between the two groups with 19% having a normal count. Patterns of symptoms varied between the groups, and around one-third were asymptomatic in both groups. Serology was of limited use in follow-up.conclusions Eosinophil count and stool microscopy are insufficiently sensitive to be used alone for screening strongyloides. The sensitivity of serology is good in immigrants with chronic infection, but lower in travellers.

Evidence-based clinical guidelines for immigrants and refugees

“…We reviewed the titles of all 5189 articles, and evaluated 445 abstracts for potential relevance, eliminating 437 because they did not fulfill our in clusion criteria. Of the remaining eight manuscripts, five pertained to the diagnosis of strongyloidiasis [313][314][315][316] or schistosomiasis, 317 and the remaining three pertained to treatment of these conditions. 318−320 Although our search did not identify any systematic reviews on the diagnosis of either parasite or the treatment of strongyloidiasis, we found a systematic review pertaining to the treatment of schistosomiasis.…”

Strongyloidiasis – the most neglected of the neglected tropical diseases?

“…In specific target populations, such as immigrants to non-endemic regions, serology has proven to be a valuable tool for screening and for the evaluation of therapies; 12 however, serology seems to lack sufficient sensitivity to diagnose recently acquired infections. 13 Although serology seems to have good negative predictive value if used in endemic areas, 14 specificity appears to be more problematic as pronounced crossreactivity is observed with other helminths, especially filaria. Specific detection of Strongyloides DNA in human stool samples by real-time PCR has recently been suggested to be a promising alternative diagnostic approach, but needs further exploration.…”

Strongyloides stercoralis seroprevalence in Vietnam

“…However, patients with chronic Strongyloides infection usually have a low parasite load and irregular shedding making microscopic diagnosis insensitive. Serological methods have higher sensitivity in a chronically infected population [5]. Enzyme-linked immunosorbent assay (ELISA) to detect human immunoglobulin G (IgG) against a crude extract of infective larvae is one of the most widely used techniques for the diagnosis of strongyloidiasis, with sensitivity rates between 73% and 100% [6].…”