Asymptomatic Fasciola hepatica Infection presenting with Hypereosinophilia

Abstract

Background: Fascioliasis is a worldwide zoonosis caused by trematodes F. hepatica and F. gigantica. The clinical signs, symptoms and laboratory tests are related to acute, latent or chronic phase of infection. Usually it is characterized by fever, abdominal pain, hepatosplenomegaly, high leukocyte count, vague gastrointestinal disturbances, biliary obstruction with intermittent jaundice, and eosinophilia. Methods and findings: A 7-year-old girl from a rural Andean area of Ecuador presented with a persistent hypereosinophilia. Leukocyte count was 35,200 mm3, with 60% eosinophilia. Anamnesis and physical examination did not reveal any signs or symptoms of infection. Ova, characteristic of Fasciola spp. were observed in the patient’s stool by direct microscopic examination and confirmed to be F. hepatica by the sequence analysis of the PCR amplicons of the second internal transcribed spacer (ITS2) gene. Abdominal ultrasonography showed a liver of normal shape, size and location with no dilation of the intra or extra-hepatic biliary tract. The patient was successfully treated with triclabendazole, 10 mg/kg for two consecutive days. Conclusions: Clinicians and lab technicians working in endemic and non-endemic areas for fascioliasis should consider the possibility of this parasitic infection in clinically asymptomatic patients with persistent eosinophilia in order to avoid erroneous diagnosis and therapeutic interventions.