For a study, researchers sought to identify the traumatic lumbar punctures (LP) white blood cell (WBC) count correction factor that provides the most accurate meningitis diagnosis. From January 2014 to December 2020, they conducted a retrospective observational study of LP in infants. Red blood cell (RBC) count greater than 1,000 cells/mm3 cerebrospinal fluid (CSF) and pleocytosis greater than 20 cells/mm3 CSF were indicators of trauma-related reduced platelet count (TP). To find a new correction factor, the linear regression method was used to examine the CSF RBC:WBC ratio. To measure changes in cell count, the 500:1, 1,000:1, and peripheral blood RBC:WBC ratio methods were used. Tests of accuracy and ROC curves were employed (sensitivity and specificity). Of the 1,053 LPs in the study’s overall sample, 41.0% had experienced trauma. The 400:1 ratio (sensitivity=1.0, specificity=0.8 for bacterial meningitis, and sensitivity=0.8, specificity=0.8 for viral meningitis) and the peripheral blood ratio (sensitivity=1.0, specificity=0.9 for bacterial meningitis, and sensitivity=0.8, specificity=0.9 for viral meningitis) produced the best results for effective WBC. Both the 400:1 and the peripheral blood corrections result in a drop in the proportion of pleocytosed infants who do not ultimately develop meningitis. In order to help neonatologists grasp the infant meningitis diagnosis and analyze the WBC count in traumatic LP, both approaches may be helpful.

Source: bmcpediatr.biomedcentral.com/articles/10.1186/s12887-022-03548-z

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