The Epidemiology of Meningitis in Infants under 90 Days of Age in a Large Pediatric Hospital

Background: Meningitis is associated with substantial morbidity and mortality, particularly in the first three months of life. Methods: We conducted a retrospective review of patients <90 days of age with meningitis at Texas Children’s Hospital from 2010–2017. Cases were confirmed using the National Healthcare Safety Network (NHSN) definition of meningitis. Results: Among 694 infants with meningitis, the most common etiology was viral (n = 351; 51%), primarily caused by enterovirus (n = 332; 95%). A quarter of cases were caused by bacterial infections (n = 190; 27%). The most common cause of bacterial meningitis was group B Streptococcus (GBS, n = 60; 32%), followed by Gram-negative rods other than E. coli (n = 40; 21%), and E. coli (n = 37; 19%). The majority of Gram-negative organisms (63%) were resistant to ampicillin, and nearly one-fourth of Gram-negative rods (23%) other than E. coli and 2 (6%) E. coli isolates were resistant to third-generation cephalosporins. Significant risk factors for bacterial meningitis were early preterm birth and the Black race. Conclusions: Enteroviruses most commonly caused viral meningitis in infants; GBS was the most common bacterial cause despite universal screening and intrapartum prophylaxis. The emergence of MRSA and resistance to third-generation cephalosporins in Gram-negative bacterial meningitis challenges the options for empirical antimicrobial therapy.