Cerebrospinal Fluid Analysis Predicts Enhancement on MRI in Bacterial and Tuberculous Meningitis: A Retrospective Observational Study

Abstract

Background Along with cerebrospinal fluid (CSF) analysis, enhancement on contrast-enhanced MRI scans are useful to diagnose and presume the pathogen of meningitis. However, the conditions for its appearance have not been clarified. This study aimed to investigate the possibility of CSF parameters as predictors of the existence of enhancement on contrast-enhanced head or spinal MRI scans in patients with bacterial meningitis (BM) or tuberculous meningitis (TM).Methods A total of 12 patients with BM and 23 patients with TM who underwent both CSF analyses and contrast-enhanced MRI scans were included in this study. The correlation between CSF analyses and MRI findings has been examined using receiver operating characteristic (ROC) analysis.Results Contrast enhancement was found in 7 and 10 patients with BM and TM, respectively. In patients with BM, higher CSF protein and lower CSF glucose were associated with the presence of the enhancement on MRI, while the CSF leukocyte or neutrocyte count did not show any difference. In contrast, not only the CSF protein and glucose but also the leukocyte and lymphocyte counts were associated with the enhancement in patients with TM. Furthermore, CSF adenosine deaminase (ADA) in patients with TM showed neither correlation with CSF leukocyte count nor discriminant ability of the MRI findings.Conclusions CSF analysis predicts the existence of enhancement on contrast-enhanced MRI scans of the central nervous system both in patients with BM and those with TM. Our findings about the CSF cell count and CSF ADA indicate the mechanism of the blood–brain barrier (BBB) breakdown in BM and TM.