942. Epidemiology of Bacterial Meningitis in Full-Term, Previously Healthy Infants Age 1 Week to 3 Months
Session: Poster Abstract Session: Central Nervous System Infections in Children
Saturday, October 22, 2011
Room: Poster Hall B1
Background: Bacterial meningitis in young infants has remained an important ongoing concern for decades. This study focuses on the incidence of bacterial meningitis in 1 week to 3 month old infants enrolled in a large health maintenance organization (HMO).

Methods: We performed a retrospective analysis of all cerebral spinal fluid (CSF) cultures collected at Kaiser Permanente Northern California (KPNC) on full term, previously healthy infants age 1 week to 3 months in outpatient clinics, the emergency department and first 24 hours of hospitalization from January 01, 2005 through December 31, 2009. All patients with CSF cultures having bacterial growth had their medical records reviewed. 

Results: There were 160,818 full term infants born during the study period, with a total of 42 positive CSF cultures. Of these, 13 (31%) were positive with a pathogen.  The three pathogens identified were Escherichia coli, Group B Streptococcus (GBS) and Streptococcus pneumoniae.  The incidence rate of true bacterial meningitis was 0.08/1000 full term births. Escherichia coli, Group B Streptococcus (GBS) and Streptococcus pneumoniae meningitis occurred in 0.037, 0.031 and 0.012 per 1000 full term births, respectively.  The most common pathogen was E. coli (6/13, 46%).  All patients with E. coli meningitis had a urinary tract infection (UTI); however, only 4/6 had concomitant bacteremia. GBS was the second most common pathogen (5/13, 38%).  Only one case of GBS meningitis occurred outside the neonatal period. Both cases of S. pneumoniae meningitis occurred outside the neonatal period and were associated with markedly elevated white blood cell (WBC) counts (>25,000 K/uL). There were no cases of Listeria monocytogenes or Neisseria meningitidis meningitis. There were no ampicillin resistant pathogens.

Conclusion: This large cohort study has identified a shift in the epidemiology of bacterial meningitis in term infants from GBS to E. coli meningitis. Although bacterial meningitis was a rare occurrence in infants, it did occur in 0.08/1000 full term births.  Three infants with bacterial meningitis did not have concomitant bacteremia. 

Subject Category: P. Pediatric and perinatal infections

Tara Greenhow, MD, Pediatric Infectious Diseases, Kaiser Permanente Northern California, San Francisco, CA, Susannah Kussmaul, MD, Pediatrics, UCSF, San Francisco, CA, Yun-Yi Hung, PhD, Kaiser Permanente Northern California, Oakland, CA and Arnd Herz, MD, Kaiser Permanente Northern California, Hayward, CA


T. Greenhow, None

S. Kussmaul, None

Y. Y. Hung, None

A. Herz, None

Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.