Praziquantel Treatment of an Eosinophilic Pleuritis Patient Suspected to Be Due to Sparganum Infection

Human sparganosis is caused by the larval tapeworm of genus Spirometra. This parasite commonly invades subcutaneous tissues and muscles. However, infection in the pleural cavity is rare. A 65-year-old male patient, who had undergone surgical excision of subcutaneous masses due to a parasite infection (presumed to have been sparganosis) approximately 10 years ago, showed pleural effusion and peripheral eosinophilia. The anti-sparganum specific IgG antibody levels in the serum and pleural fluid were significantly higher than the normal control levels. Three consecutive doses of praziquantel (75 mg/kg/day) were administered for control of pleural effusion and peripheral eosinophilia. In this patient, sparganosis was suspected, and the probable cause of the infection was ingestion of raw snakes and frogs. Immunoserologic tests using ELISA can be helpful in diagnosis of pleural sparganosis and praziquantel is suggested as an alternative treatment for surgically unresectable cases.