Diffusion-weighted imaging abnormalities patterns in bacterial meningitis.

PURPOSE: Information on abnormal diffusion-weighted imaging (DWI) patterns in bacterial meningitis (BM) is limited. This study aimed to investigate the frequency and patterns of DWI abnormalities in BM in patients with culture-positive BM.

METHODS

The medical records of 14 consecutive patients with BM with magnetic resonance imaging evaluation, admitted to our hospital over the past 14 years, were reviewed. BM was defined by a cerebrospinal fluid (CSF) culture positive for bacteria, or the combination of CSF pleocytosis and a positive blood culture.

RESULTS

Brain DWI abnormalities were identified in 13 (93 %) of the 14 patients and classified into six patterns: ischaemic stroke (n = 9), ventriculitis (n = 4), sulcal hyperintensity (n = 7), scattered hyperintensities surrounding the cerebral hemispheres (n = 6), middle meningeal arterial sign (n = 5), or abscess (n = 1). The causes of ischaemic stroke included infective endocarditis (n = 4), vasculitis (vasculopathy; n = 2), and unclassified (n = 3).

CONCLUSION

DWI abnormalities in BM were very frequent. Based on the high frequency and wide spectrum of DWI abnormalities in BM, we suggest performing DWI for all patients with BM.