A high degree of suspicion in refugees is needed to make the diagnosis
When a patient is from an endemic area, such as Southeast Asia, Latin America, or sub-Saharan Africa7, one’s clinical suspicion should increase. Also, because signs and symptoms of strongyloidiasis are often nonspecific, a high suspicion for the disease is necessary to prompt testing. Eosinophilia may be present, but can be mild, and is not specific for the disease.
Available stool testing is not highly sensitive, and repeated specialized stool examinations are required, with sensitivity reaching close to 100% only after 7 serial samples are examined.3,8 Duodenal aspirate is more sensitive and larvae can also be seen through wet mount of bronchoalveolar lavage fluid. Serologic testing for Strongyloides IgG is available and has high sensitivity. However, specificity can be low because there can be cross-reactivity with other parasites, and the presence of the antibody does not differentiate between past and current infection.3,5,8
Imaging of the lungs is often variable and nonspecific. Findings on a chest x-ray or CT scan of the chest include diffuse alveolar opacities, interstitial infiltrates, pleural effusions, abscess or cavitation, or fibrotic changes.7 However, these findings can also be the result of a bacterial superinfection and not the parasite itself.3,6