Sera of all patients were tested for specific antibodies against the 21 and/or 24-kDa antigenic bands of G. spinigerum and the 29-kDa band of A. cantonensis by immunoblotting. The methods of the technique are described below and are composed of two steps: (i) the creation of antigenic bands by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and (ii) the detection of antibodies against the specific polypeptide band by immunoblot analysis.