Neonatal sepsis: Gram-negative bacterial profile, antimicrobial resistance pattern, risk factors and preventive measures

Background: Sepsis, particularly bacterial sepsis, is still a leading cause of infant mortality, whether it is early onset sepsis (EOS) or late onset sepsis (LOS), despite much notable global advancements in lowering neonatal mortality. Neonatal sepsis continues to the third leading cause of neonatal death worldwide. Gram-negative bacteria (GNBs) namely, Escherichia coli, Klebsiella pneumonia and Pseudomonas aeruginosa contribute to 20% to 42% of LOS cases. Neonates acquire infection through various ways such as, from maternal flora, in-utero infection and might be attributed from community and hospitals. K. pneumoniae is the major and leading sepsis causing pathogen worldwide followed by E. coli, Acinetobacter baumannii and others. Such pathogenic bacteria often develop resistance to antibiotic treatment, either as a result of first-line therapy with ampicillin and gentamicin or second-line therapy with amikacin, ceftazidime, and meropenem, as advised by the World Health Organisation (WHO). Early diagnosis of bacteria and antibiotic treatment are essential to lowering morbidity and mortality. Modern medications' invasive therapeutic procedures and diagnostics have raised the risk of infection and given rise to new microbes. In addition, the overuse of antibiotics has caused bacterial genetic mutations that have produced new resistant species that have spread swiftly throughout the community and in hospitals. This review was aimed to understand current scenario of neonatal sepsis and providing comprehensive overview of predominating Gram-negative bacteria in neonatal sepsis along with antimicrobial resistance, risk factors, prevention and management.