Use of Endotoxin Antigens in Enzyme-Linked Immunosorbent Assay for the Diagnosis of P.pseudomallei Infections (Melioidosis)

SUMMARY An enzyme-linked immunosorbent assay (ELISA) with endotoxin preparations of P.pseudomallei as antigen was developed for detection of IgG anti­ bodies specific to melioidosis. Forty·seven sera of bacteriologically confirmed melioi· dosls patients, 55 non-melioidosis sera and 50 sera of healthy blood donors from non·endemlc areas were subjected to this assay in comparison with Indirect hemag­ glutination assay (IHA). The data were treated by receiver operating characteristics analysis. The sensitivity, specificity and accuracy In this ELISA were 95.7%, 94.2%, and 94.7%, respectively, with cut·off value of 00 = 0.312 at 490 nm. Meanwhile, those In IHA were 81.0%, 91.4%, and 88.1%, respectively, with a cut·off value of ;;;'1:160. From these results, the ELISA was judged to be more reliable than IHA as the seroassay for diagnosis of melioidosis. synthesis. This information prompted us to an attempt of ELISA with endotoxin preparations as antigen in melioidosis patients, non-melioi­ dosis patients and healthy blood donors. The data presented here are compared with those of IHA together with receiver operating characteristic (ROC) analysis.