Strongyloidiasis Diagnosed by ELISA in Brussels: A Bicentric Retrospective Study

Despite a significant population of migrants from endemic countries and of Europeans traveling to these regions, no Belgian study and few European studies have reported on strongyloidiasis. This retrospective study, conducted between January 2012 and December 2021, aimed to compare demographic data, clinical characteristics and management appropriateness of adult patients from Hôpital Universitaire de Bruxelles-Erasme and Centre Hospitalier Universitaire Saint-Pierre who had a positive serology for Strongyloides stercoralis. Serology results were classified as weakly positive (WP) or positive (P), and the two groups were compared. Qualitative and continuous data were expressed as numbers and medians, respectively, and compared using Fisher's exact or Wilcoxon-Mann-Whitney tests, with a p-value < 0.05 considered statistically significant. A total of 358 patients (50% females) were included, with a median age of 52 (IQR: 40-63): 225 (62.8%) had WP and 133 (37.2%) had P results. Overall, 217/358 (60.6%) of the patients had at least one comorbidity, and 52/358 (14.5%) had an immunosuppressive factor. In total, 120/358 (33.5%) were symptomatic and 160/352 (45.5%) had blood eosinophilia. Only 51/358 (14.2%) benefitted from appropriate clinical management. Severe complications occurred in 17/358 (4.7%) patients, with two deaths (0.6%). This first Belgian study about strongyloidiasis shows that, despite low rates of severe complications and mortality, significant treatment delays were observed, requiring future improvement and monitoring.