Reassessing the Value of CSF Protein and Glucose Measurement in Pediatric Infectious Meningitis.

Abstract

Infectious meningitis (IM) in US children is increasingly rare and new rapid multiplex PCR-based testing is increasingly available. We evaluated the added value of cerebrospinal fluid (CSF) protein and glucose tests to predict IM when compared with information provided by CSF white blood cell count (WBC) and multiplex polymerase chain reaction (PCR). We retrospectively reviewed CSF results from October 2015 to August 2017 in patients 0 to 18 years at a US children's hospital. Noninfectious evaluations were excluded. Test characteristics were calculated for CSF WBC, protein, and glucose in isolation and in parallel for prediction of microbiologically confirmed IM. Chart review was performed to identify consideration of protein and glucose in medical decision-making (MDM). We identified 735 patients including 446 <2 months; 45 (6.1%) had microbiologically-confirmed IM, including 23 (5.2%) age <2 months. Multiplex PCR and/or CSF WBC identified all IM patients. When added to CSF WBC, measurement of glucose made no contribution to sensitivity, specificity, positive predictive value (PPV) or negative predictive value (NPV), and protein had no impact on sensitivity and decreased the specificity, PPV, and NPV compared with CSF WBC alone. Abnormal protein was documented in MDM in 6 (0.8%) patients, all of whom had elevated WBC counts also cited. Glucose was not mentioned in MDM. Multiplex PCR testing and WBC may be sufficient to predict meningitis in children in low incidence settings. Protein and glucose did not contribute significant additional information. More intentional use of protein and glucose testing in patients with suspected IM may achieve higher value care.