Investigators from the Children’s Hospital of Pittsburgh, PA, reviewed the literature on the role of MRI as an adjunct for diagnosing meningitis. Of 7 relevant articles, two were reviews and an opinion of usefulness of the MRI was based on 5 articles. Specificity of MRI (i.e. negative imaging findings in those who did not have meningitis) was high and ranged from 93% to 100%. Sensitivity of the MRI was more variable (9%, 85%, 95% and 100%); sensitivity may be higher for bacterial and fungal meningitis than for viral meningitis, but it may depend on the degree of inflammatory response and may vary with etiology. The MRI sequences may vary in yield, the contrast-enhanced FLAIR being most useful in a number of studies. Most of the studies included children, but the majority involved adults.

Based on the studies reviewed, MRI is not recommended to rule out meningitis due to its poor sensitivity; it may be more useful for bacterial compared to viral meningitis, but sensitivity varies depending on MRI technique used and data are limited. MRI is more specific but cannot be recommended to rule in meningitis because data are limited for children and none for infants. [1]

COMMENT. If further studies provide a more definitive role, MRI could be of diagnostic value in neonates and small children with traumatic lumbar punctures, to avoid unnecessary long-term antibiotics and extended hospital stay.