Human lung fluke Paragonimus heterotremus: differential diagnosis between Paragonimus heterotremus and Paragonimus westermani infections by EITB.

The specificity of three major polypeptides (35, 33 and 32.5 kD) from Paragonimus heterotremus antigens prepared from ether-extracted adult worms was tested against sera from heterologous infections as well as against P. westermani-infected sera. Only the 35 kD polypeptide was not present, its antigenic determinant being bound to the antibodies from all P. westermani-infected cases. Its cross-reactivity against various sera from heterologous helminthiases and other lung infections showed that it is not bound to these antigenic polypeptides. These major bands cannot be detected by Concanavalin A detector. Our research encourages the pattern (35, 33 and 32.5 kD) of immunoblot reactions for the diagnosis of P. heterotremus infections; the 35 kD antigen is specific for corresponding species and able to differentiate infections between both species of Paragonimus.