Eosinophilia in Refugee Patients

Overview

Eosinophilia (elevated eosinophil count) is common in refugee patients. Helminth (worm) infections are the most frequent cause and should be ruled out before investigating other causes.

Step-wise Approach

Step 1 - Rule Out Strongyloidiasis and Schistosomiasis

These serologies should already have been ordered as part of the initial screening tests. If positive, treat first. See Strongyloides and Schistosomiasis pages. Repeat CBC at least 4 weeks after treatment to reassess eosinophil count. If eosinophilia persists, proceed to Step 2.

Step 2 - Look for Other Helminth Infections

Order at least 3 serial stool Ova and Parasites examinations. Stool microscopy has low sensitivity, so repeat testing increases yield.

Practical note: If stool samples are difficult to obtain, it is reasonable and safe to treat empirically with mebendazole 500 mg once (or 100 mg twice daily for 3 days) for patients over 2 years of age.

Fill out the CLS Stool and Parasite History Form when ordering these tests.

Step 3 - Test for Other Parasites

If initial serologies and stool exams are negative, consider: trichinella, filariae, flukes, toxocara (especially in children). Refer to Infectious Diseases for this step.

Calgary: Tropical Infectious Diseases Clinics Calgary

Step 4 - Look for Non-Infectious Causes

If parasitic workup is negative, consider medication-related eosinophilia, asthma or atopy, hematologic diseases, vasculitis, or organ-specific eosinophilic conditions.

Initial investigations: peripheral blood smear, electrolytes, creatinine, urinalysis, B12, liver function tests, troponin, chest X-ray.