Recurrent Community-Acquired Bacterial Meningitis in Adults

BACKGROUND: Recurrent bacterial meningitis has been found to occur in about 5% of meningitis cases. METHODS: We analyzed adults with recurrent episodes in a prospective nationwide cohort study of community-acquired bacterial meningitis. RESULTS: Of 2264 episodes of community-acquired bacterial meningitis between 2006 and 2018, 143 (6%) were identified as recurrent episodes in 123 patients. The median age was 57 years (interquartile range [IQR], 43–66), and 57 episodes (46%) occurred in men. The median duration between the first and the current episode was 5 years (IQR, 1–15). For 82 of 123 patients (67%), it was the first recurrent episode, 31 patients had 2–5 previous episodes (25%), 2 had 6–10 episodes (2%), and 2 had >10 episodes (2%). Predisposing factors were identified in 87 of 118 patients (74%) and most commonly consisted of ear or sinus infections (43 of 120, 36%) and cerebrospinal fluid leakage (37 of 116, 32%). The most common pathogens were Streptococcus pneumoniae (93 of 143, 65%) and Haemophilus influenzae (19 of 143, 13%). The outcome was unfavorable (Glasgow outcome scale score, <5) in 24 episodes with recurrent meningitis (17%) vs 810 for nonrecurrent meningitis patients (39%, P < .001). Six of 143 died (4%) vs 362 of 2095 patients (17%, P < .001). CONCLUSIONS: Recurrent meningitis occurs mainly in patients with ear or sinus infections and cerebrospinal fluid leakage. Predominant causative pathogens are S. pneumoniae and H. influenzae. The disease course is less severe, resulting in lower case fatality compared with nonrecurrent meningitis patients.