A cohort study published in 2015 of 82 children diagnosed with meningitisdemonstrated that serum PCT levels are related to the severity of infection inpatients with bacterial meningitis and that a decrease in PCT levels in responseto treatment was a good predictor of favorable prognosis.(34) A meta-analysis published inthe same year showed that PCT is highly accurate in differentiating bacterialand viral meningitis in children, with 96% sensitivity and 89%specificity.(35). The gene discussed is CALCA; the disease is bacterial meningitis.