Analysis of the 144 blinded serum samples from patients with suspected leptospirosis, tested using both the IgM ELISA and the IgM dot-blot kit showed almost perfect agreement (Kappa = 0.81) with 84.6% sensitivity, 96.6% specificity, and 94.4% accuracy (Table 2). This evidence concerns the gene CD40LG and leptospirosis.