Comparison of CSF and MRI Findings among Neonates and Infants with or Group B Streptococcal Meningitis.

BACKGROUND AND PURPOSE

Group B and () are the 2 most common causes of bacterial meningitis in neonates. The purpose of this study was to determine whether CSF and/or MR imaging findings differ between infants with group B streptococcal or meningitis.

MATERIALS AND METHODS

A retrospective review was performed among neonates (younger than 28 days) and infants (younger than 120 days) with proved group B streptococcal ( = 57) or meningitis ( = 50). A CSF or blood culture positive for and an elevated CSF white blood cell count were used as the criterion standard. Independent, blinded review of brain MRIs obtained within 21 days of presentation were performed by 2 board-certified neuroradiologists. CSF laboratory values and MR imaging findings were compared between the groups.

RESULTS

There was no statistically significant difference between the mean age at presentation for patients with group B streptococcal (40 days; range, 2-111 days) versus patients with meningitis (31 days; range, 12-115 days) ( = .18). There was no statistically significant difference in the CSF white blood cell count, glucose, or protein. There was a significant difference between group B streptococcal and meningitis in the frequency of hydrocephalus (0% versus 22%, = .001) and infarct (40% versus 14%; = .038), respectively. There was no statistically significant difference in leptomeningeal enhancement, cerebritis, ventriculitis, abscess/granuloma, subdural effusion, extra-axial purulent material, intraventricular purulent material, hemorrhage, and sinus thrombosis.

CONCLUSIONS

Although neonates and infants with group B streptococcal or meningitis had similar age and CSF laboratory values, patients with group B streptococcal meningitis more frequently demonstrated infarcts, while those with meningitis more frequently had early onset of hydrocephalus.