EXTRAORDINARILY HIGH EOSINOPHILIA AND ELEVATED SERUM INTERLEUKIN-5 LEVEL OBSERVED IN A PATIENT INFECTED WITH PARAGONIMUS-WESTERMANI

Objective. Although eosinophilia is one of the typical clinical featur es of some helminth infections, the degree of eosinophilia in helminth iasis is usually 10% to 30% with a total white blood cell count of 10 000 to 20 000/mm(3). Here we report a case of ext aordinarily high eos inophilia (91%; absolute eosinophil count, 84 000/mm(3)) caused by Par agonimus westermani infection. To determine the mechanisms of eosinoph ilia, the levels of several eosinophilopoietic cytokines in the patien t's sera were measured during the course of treatment. Methods. Serum levels of three cytokines, granulocyte-macrophage colony-stimulating f actor, interleukin-3 (IL-3), and IL-5 were measured by enzyme-linked i mmunosorbent assay using commercial kits or our own assay system for I L-5. Results. Although the kinetic changes of IL-5 correlated well wit h eosinophilia, the serum IL-3 level remained below the detection leve l throughout the period examined. Although the granulocyte-macrophage colony-stimulating factor level was twofold to threefold higher than t he normal level, its kinetics did not parallel the degree of eosinophi lia. Conclusions. These results show that Paragonimus westermani infec tion can induce an extraordinarily high level of eosinophilia with an associated increase in IL-5 production. Immunoserologic diagnosis for parasitic diseases should be included in the differential diagnosis of eosinophilia.