ELISA for immunodiagnosis of human gnathostomiasis

An ELISA for immunodiagnosis of human gnathostomiasis using a crude water extract of third-stage larvae of G. spinigerum as antigen, and alkaline phosphatase labelled goat antihuman IgG in the indicator system was developed and evaluated. At the titre of 1:400 and above positive results were observed in 100% of 4 parasitological confirmed and 10 eosinophilic meningo-encephalitis (EME) typical of gnathostomiasis cases, 56% of 160 cutaneous migratory swelling cases, 33% of 24 cases with EME typical of A. cantonensis infections, 23% of 92 cases with other parasitic infections and 1.5% of blood donors. The overall sensitivity was 59% and specificity 84%. The predictive value was 77%. The results indicated that ELISA is potentially useful for immunodiagnosis of gnathostomiasis but improvement of sensitivity and specificity is needed.