Upon admission, IL-8 concentrations were substantially higher in deceased kala-azar patients (median 76.5 pg/mL [IQR 35.2–242.4 pg/mL]) than in survivors (median 26.4 pg/mL [IQR 15.1–47.7 pg/mL]; p < 0.0001). This evidence concerns the gene CXCL8 and visceral leishmaniasis.