An optimal cut-off value of 2.2 μg/mL plasmatic calprotectin was identified to distinguish between infants with sepsis and infants without sepsis, with sensitivity and specificity of 62.5% and 69.7%, respectively, whereas CRP for a cut-off of 0.6 showed a sensitivity of 50% and specificity of 66.7%. The gene discussed is CRP; the disease is Sepsis.