Interpretation of Traumatic Lumbar Puncture in Aseptic Meningitis

Sung, Su Jin; Kim, In Jung

Abstract

PURPOSE
This study was undertaken to find out a useful method that can predict the true leukocytosis in blood-contaminated cerebrospinal fluid(CSF) due to traumatic lumbar puncture(LP), using white and red cell counts of sanguineous CSF and peripheral blood.
METHODS
From May 2001 to December 2002, among 1,247 patients presenting symptoms of meningitis who had received LP at Chonnam Hospital, 126 patients were included in this study who had undergone a second LP due to a traumatic first one. According to the final results of second LP, they were devided into two groups, aseptic meningitis group; and normal CSF group. Medical records were reviewed retrospectively, the proportions of white blood cells to red blood cells were obtained in the peripheral blood(WBC:RBCBlood) and CSF(WBC:RBCCSF), based on the results of the traumatic first LP and simultaneously performed peripheral blood count. The WBC:RBCCSF/WBC:RBCBlood ratio was calculated in each patient.
RESULTS
The WBC:RBCCSF/WBC:RBCBlood of the normal CSF group was 13.5+/-7.3(standard deviation), significantly lower than 47.3+/-39.5 of the aseptic meningitis group.
CONCLUSION
The WBC:RBCCSF/WBC:RBCBlood is a useful value to predict frank leukocytosis in the blood-contaminated CSF due to traumatic LP, but all clinical and laboratory informations must be considered before deciding on a treatment strategy to minimize the risk of misdiagnosis.