Cerebral Vasculopathy Causes Stroke in Patients With Bacterial Meningitis

Ischemic stroke associated with bacterial meningitis is caused by cerebral vasculopathy around the focus of the infection, according to findings from a cohort study and meta-analysis published in the Annals of Neurology.

Bacterial meningitis continues to be a global health problem. Following a community-acquired bacterial meningitis infection, cerebrovascular complications are linked to worse outcomes, such as thrombosis, acute cerebral hemorrhage, vasculitis, and the formation of mycotic aneurysms in large, medium, or small cerebral vessels. The exact pathophysiologic background and differences in factors associated with cerebral infarction in bacterial meningitis remain unknown.

For the study, researchers sought to describe clinical, imaging, and laboratory features of patients with bacterial meningitis that is complicated by occurrence of ischemic stroke. They conducted a single-center cohort study at a tertiary care center and a meta-analysis of published studies, in which cohorts and case studies of patients with bacterial meningitis and ischemic stroke have been reported.

A total of 102 adults with community-acquired bacterial meningitis participated in the single-center cohort study and admitted to University Hospital of Munster’s department of neurology between May 2009 and February 2020. Among the patients, the median age at first presentation was 58 years, and 51% were women. A total of 19 individuals with concomitant ischemic stroke were identified.

Researchers assessed patients’ clinical characteristics, cerebrospinal fluid analyses, and spatiotemporal distribution of infarcts. They found that 15 of the 19 patients with stroke (78.9%) and 33 patients without stroke (39.8%) had a modified Rankin scale (mRS) of 3 or more at discharge (P <.01).

For the meta-analysis, the researchers identified 15 cohort studies from the PubMed database from its inception to August 2021. A total of 1692 patients with bacterial meningitis were included in the studies with 332 of those patients (16%) who experienced cerebral infarcts (95% CI, 0.13-0.20). The occurrence of ischemic stroke in patients with bacterial meningitis was associated with significantly higher mortality rates (odds ratio, 2.38; 95% CI, 1.70-3.34; P <.0001). Among individuals who experienced an ischemic stroke, vasculopathy was seen in 63.2% and additional intracerebral hemorrhage in 15.8%.

A study limitation included the strict inclusion criteria used in the study; this may have led to a risk of introducing a bias toward more severe cases of disease.

“Even though the time course of infarctions would enable a therapeutic intervention, to date, there is no specific treatment to prevent ischemic complications in bacterial meningitis,” the researchers noted. “[F]urther knowledge of underlying [pathophysiologic] mechanisms resulting in a high risk [for] ischemic stroke in patients with bacterial meningitis needs to be elucidated,” they concluded.