[Diagnostic and treatment of hypereosinophilia upon return from the tropics: 102 patients].

Management of blood eosinophilia in travelers returning from the tropics is controversial. In this prospective study, 102 asymptomatic tropical travelers underwent investigation and treatment for hypereosinophilia. In contrast with direct tests for parasitic infection which were positive in only 15% of cases, immunological tests were suggestive of helminthic infection is 77%. The most common diagnoses were toxocarosis (49%), strongyloidiasis (30%), and filariasis (19%). Anti-parasite treatment was undertaken based on laboratory findings (12 cases) or on presumptive diagnosis using two-agent therapy (ivermectin and praziquantel) in 13 cases or three-agent therapy (ivermectin, praziquantel, flubendazole) in 77 cases. As a result of treatment, eosinophil count returned to normal in 61% of cases and decreased in 30%. These findings suggest that presumptive treatment of blood eosinophilia can be undertaken in tropical travelers using three anti-parasitic drugs: ivermectin (1 x 0.4 mg/kg), flubendazole (2 x 100 mg per day for 3 days), and praziquantel (1 x 40 mg). As a precaution before using ivermectin, tests should be performed to detect loiasis which can lead to adverse reactions.