Immunoelectrophoresis tests showing Echinococcus granulosus arc 5 in human cases of Echinococcus vogeli and cysticercosis-multiple myeloma.

Human sera from one case of polycystic hydatidosis due to Echnincoccus vogeli and from a case of cysticercosis and multiple myeloma were positive to the immunoelectrophoresis (IEP) test for hydatidosis based on the E. granulosus arc 5 positivity criterion. Arc 5 can therefore be elicited in IEP tests of human sera not only by E. granulosus and E. multilocularis but also by E. vogeli antigens. Whether the cross reaction observed in the second serum was due to the multiple myeloma or to the cysticerci remains to be determined. Although arc 5 antigens are known to be present in Taenia hydatigena cyst fluid this is the first report of an arc 5 due to antigens other than Echinococcus in IEP of human sera.