Burden, risk factors, and emerging microbiological trends of Gram-negative neonatal sepsis in Jordan: a retrospective cohort study

Background Neonatal sepsis (NS) is a major cause of morbidity and mortality, particularly in low- and middle-income countries. Gram-negative bacteria are increasingly predominant and associated with severe disease. In Jordan, data on Gram-negative NS are limited, highlighting the need for local evidence to guide early detection and treatment. Objective To determine the incidence, risk factors, bacterial profile, and antimicrobial resistance patterns of Gram-negative NS in a tertiary Neonatal Intensive Care Unit (NICU) in Jordan. Methods A retrospective cohort study reviewed 4,804 blood cultures from 3,429 neonates admitted to the NICU at Jordan University Hospital over six years. Clinical, maternal, and perinatal data were extracted from electronic health records. Descriptive statistics were used to summarize patient characteristics and microbiological findings, while regression analysis was used to identify risk factors for Gram-negative NS. Results Among 4,172 blood cultures, 72 Gram-negative NS cases were identified, with a cumulative incidence of 9.7 per 1,000 NICU admissions. Extremely preterm neonates and those receiving early invasive interventions had higher risk (aOR 1.88–6.89), while elevated C-reactive protein and thrombocytopenia were independently associated. Klebsiella pneumoniae (30.6%) and Escherichia coli (22.2%) predominated. Multidrug resistance was observed in 34.7% of isolates, 23.6% were extended-spectrum β-lactamase producers, with high cephalosporin resistance and alarming meropenem resistance (33.3%). Conclusion Multidrug-resistant Gram-negative pathogens remain the predominant cause of neonatal sepsis in this Jordanian tertiary NICU, with emerging resistance to last-line antibiotics, including carbapenems. These findings highlight the importance of ongoing surveillance and support future efforts in infection prevention and antibiotic stewardship.