[A case of Paragonimus miyazakii with migrating infiltrates: use of ELISA in diagnosis and treatment].

A 47-year-old man was referred to our clinic with abnormal chest radiographs. He was free of symptoms, but his chest CT demonstrated transient migrating infiltrates. Peripheral blood revealed eosinophilia and eosinophilic pneumonia was suspected. However, the bronchoalveolar lavage fluid showed no increase in eosinophils. Later, the patient's pleural effusion did contain eosinophils. His total IgE level was continuously elevated despite the absence of allergic disease, and so parasitic infection was suspected. Ouchterlony's double diffusion test after absorption of Paragonimus westermanii antigen was positive for Paragonimus miyazakii antigen. The ELISA values of both serum sample and pleural effusion were increased. As the ELISA value of the pleural effusion was higher than the serum one, we realised that pleural effusion was caused by Paragonimus miyazakii. Treatment with praziquantel for 3 days resulted in disappearance of the abnormal chest radiographic findings, and a reduced blood eosinophil level, IgE level and ELISA titre for Paragonimus miyazakii. We concluded that ELISA was useful in the diagnosis and assessment for treatment in Paragonimus miyazakii infections although there was no clearly relevant history.