Prognostic utility of the semi-quantitative procalcitonin test, neutrophil count and C-reactive protein in meningococcal infection in children

The aim was to determine whether semi-quantitative procalcitonin (PCT-Q) measurements on admission can identify the severity of meningococcal infection in children. A total of 65 children (mean age 2.4 years) with meningococcal disease were included in a prospective study. All patients were treated with antibiotics, rehydration, inotropic drugs and mechanical ventilation if presenting with shock or respiratory failure. On admission, blood was drawn for routine laboratory analyses including absolute neutrophil count (NC), C-reactive protein (CRP) and PCT-Q (immunochromatographic test). A total of 33 patients presented with septic shock on admission of whom 18 developed multiple organ dysfunction syndrome (MODS) and 9 died. Forty-three patients showed a very high PCT-Q level (>= 10 ng/ml), 12 showed values between 2-9.9 ng/ml and the remaining 10 patients showed PCT-Q levels < 2 ng/ml. All patients with a PCT-Q level < 10 ng/ml survived, whereas all those who developed MODS or died had PCT-Q levels >= 10 ng/ml. Receiver operator curve analysis showed that PCT-Q and NC had a high predictive value for MODS and death. PCT-Q showed a sensitivity of 100%, a negative predictive value of 100% and a negative likelihood ratio of 0.0 for MODS and death. Conclusion:semi-quantitative procalcitonin levels under 10 ng/ml predict good outcome of children with meningococcal infection. It is a highly sensitive method to identify patients with an increased risk of multiple organ dysfunction syndrome or death.