Pathogen Distribution of Neonatal Bacterial Meningitis in the Era of Multidrug-Resistant Bacteria: A Single-Center Experience

Abstract

Purpose: Neonatal bacterial meningitis (NBM) is a serious disease with high morbidity and mortality. This study aimed to establish a foundation for the selection of empirical antibiotics for NBM through an analysis of pathogen distribution and shift in antimicrobial resistant pattern. Patients and Methods: A retrospective cohort study on culture confirmed NBM from 2005 to 2022. Results: A total of 191 cases were enrolled, 48 for premature infants and 70 for early-onset meningitis. The incidence of NBM in first half and last half period was 0.2‰ and 0.24‰, while the mortality was 12.0% and 5.6% respectively. The top two pathogens were Escherichia coli (E. coli) (40.3%) and Group B Streptococcus (GBS) (29.8%). E. coli was the most common pathogen in both periods, Enterococcus (13.3% vs 0.9%, P < 0.05) and Staphylococcus aureus (8.4% vs 1.9%, P < 0.05) decreased, while GBS increased significantly in the periods [16.9% vs 39.8%, P < 0.001]. Gram-positive bacteria were more common in full term infants (53.8% vs 27.1%, P = 0.001), while gram-negative bacteria were more common in preterm infants (72.9% vs 46.2%, P = 0.001). All isolated GBS strains were susceptible to penicillin. On the other hand, less than 60% of E. coli were susceptible to third generation of cephalosporins, and were only susceptible to carbapenem or amikacin. This was mainly due to production of extended-spectrum beta-lactamase (ESBLs) which was higher in late-onset group than that in early-onset group (45.1% vs 19.2%, P = 0.026). Conclusion: Incidence of NBM has not changed significantly over the last 2 decades. E. coli remains as the most common pathogen of NBM despite that GBS has increased in recent 9 years, especially in full-term infants. While all isolated GBS are susceptible to penicillin, over a third of E. coli strains are multidrug resistant due to production of ESBLs.