Clonorchis sinensis, a trematode prevalent in East Asia, causes hepatobiliary infection. Exposure typically occurs through ingestion of raw or undercooked fish containing the encysted larval form of the parasite. Extrahepatobiliary disease has not commonly been described. In this case report, we describe an unusual case of C. sinensis infection associated with eosinophilic pneumonia. A middle-aged man from China presented with subacute cough and was found to have a bilateral diffuse eosinophilic pneumonia with associated peripheral eosinophilia. Stool microscopy revealed C. sinensis eggs, and the patient improved after treatment with prednisone and praziquantel. Pulmonary clonorchiasis should be considered in patients with eosinophilic pneumonia from areas highly endemic for this pathogen.
Address correspondence to Archana K. Reddy, Division of Infectious Diseases, Department of Internal Medicine, University of California-Davis Health, 4150 V St., PSSB, Suite G500, Sacramento, CA 95817. E-mail: firstname.lastname@example.org
Financial support: There was no funding source for this author-initiated project other than the general support of the authors’ time from the University of California Davis Medical Center. The corresponding author had full access to the data included in the case report and had final responsibility for the decision to submit for publication.