Application of different Paragonimus antigens to immunodiagnosis of human lung fluke infection.

Utilizing enzyme immunoassay, Paragonimus africanus, P. uterobilateralis, P. ecuadoriensis and P. westermani antigens were tested with regard to their reactivity to sera from patients infected with Paragonimus africanus, P. uterobilateralis, P. ecuadoriensis, Fasciola hepatica, Opisthorchis viverrini, different schistosomes, Cysticercus cellulosae, nematodes and from patients with nonparasitic diseases as well as from healthy blood donors. Simultaneous application of Paragonimus antigens to each serum led to a pattern of reactivity which rendered possible species-specific diagnosis. Most distinct cross reactivity occurred with fascioliasis sera, followed by opisthorchiasis, schistosomiasis and sera from patients with cysticercosis. Cross-reactivity was observed to least extent when P. westermani antigen was applied. A follow-up study of 42 paragonimiasis patients treated with praziquantel (2-cyclohexylcarbonyl-1,2,3,6,7, 11b-hexahydro-4H-pyrazino[2,1-a]isoquinolin-4-one, EMBAY 8440, Biltricide) demonstrated that substantial decrease of IgG antibodies occurred between the first and sixth months after therapy, whereas change of IgE antibody levels was less conclusive.