Altogether, 51 patients fulfilled the diagnostic criteria of acute leptospirosis either by real-time PCR (n = 30) (as per criteria (iii) and (iv)) IgM ELISA with PCR (n = 9) (as per criteria (v)) and confirmed MAT (n = 19) (as per criteria (i) and (ii)), as well as the aforementioned sample for which a sequence was produced (diagnostic criteria (vi)). The gene discussed is CD40LG; the disease is leptospirosis.