Bacterial pathogen profile and antimicrobial resistance in neonates with bloodstream infections in Dar es Salaam, Tanzania

Abstract

Abstract Background Neonatal sepsis is a systemic infection that significantly contributes to neonatal mortality. The causative agents vary by geographical location and change over time. Pathogens can be transmitted through vertical or horizontal means. Clinical presentations differ, with some neonates exhibiting multiple symptoms while others display non-specific signs. Over time, there has been increasing resistance to the antibiotics used in the empirical treatment of infectious diseases. The current retrospective cross-sectional study design examined the etiology of neonatal sepsis and antimicrobial susceptibility patterns among neonates admitted to a tertiary hospital from July 2020 to June 2022 by reviewing data for neonates with blood culture results. Results We included 282 neonates, with 52.8% being males and 72.2% aged between 1 and 3 days. Gram-positive bacteria were predominantly isolated, accounting for 66.3%, with coagulase-negative staphylococci identified as the most common pathogen, comprising 54.3% of all pathogens. Klebsiella species were the second most frequently isolated pathogens (19.5%), notably more prevalent in neonates aged 1–3 days than those aged 4–28 days (22.5% vs. 11.5%, p = 0.037). Overall, increased antimicrobial resistance was observed for penicillin (94.4%), ampicillin (91.2%), erythromycin (89.5%), aztreonam (82.4%), ceftriaxone (80.0%), gentamicin (77.9%), and trimethoprim-sulfamethoxazole (75.5%). Lower resistance rates were noted for amikacin (6.5%), imipenem (16.0%), and meropenem (18.9%). The resistance to methicillin among Staphylococcus aureus and coagulase-negative staphylococci was 68.4% and 82.3%, respectively. The overall proportion of multidrug-resistant strains was 66.5%, ranging from 57.9% (Gram-negative bacteria) to 71.2% (Gram-positive bacteria). The pathogen with the lowest rate of multidrug resistance was Pseudomonas species (18.2%). Conclusion Various pathogens, primarily Gram-positive bacteria, were identified associated with neonatal sepsis. Most pathogens exhibited resistance to commonly used antibiotics, with two-thirds showing multidrug resistance. These findings highlight the need for evidence-based antibiotic prescriptions and reinforce ongoing antimicrobial resistance surveillance and antibiotic stewardship programs.