Bacterial isolates, antibiogram and outcomes of blood culture proven sepsis in neonates at a tertiary institution in South East Nigeria: a cross-sectional study

Background: Neonatal sepsis (NNS) in developing countries continues to be a diagnostic and management challenge due to the delays in identifying the aetiologic pathogens and antibiograms.

Aim: To determine the predominant bacterial isolates, antibiotic susceptibility pattern and outcomes of blood culture proven sepsis in neonates.

Methodology: A hospital-based cross-sectional study of 120 neonates admitted into the Special Care Baby Unit (SCBU) of Nnamdi Azikiwe University Teaching Hospital Nnewi with clinical features suggestive of sepsis. A semi-structured questionnaire and proforma were used to record neonatal, maternal and laboratory information. Blood specimens were collected for aerobic culture using Bactenecin (BACTEC)-Ped plus culture system. Antibiotic susceptibility testing was performed using the Kirby Bauer disc diffusion method. Data obtained were analysed using SPSS version 23.0. p value < 0.05 was considered as significant.

Results: There were 68 males and 52 females giving a male-to-female ratio of 1.3:1. The median age at admission was 48 h. Staphylococcus aureus 13 (43.3%) was the most common bacteria isolated. The prevalence of blood culture proven sepsis were 25% and 6.7% of the subjects with positive blood culture died. Gram-positive bacteria isolated were sensitive to gentamicin, vancomycin (VA), linezolid and resistant to penicillin. Gram-negative bacteria isolated were sensitive to meropenem (MEM), imipenem (IPM), ciprofloxacin (CIP) and resistant to ceftazidime, ceftriaxone, ampicillin and amoxicillin-clavulanic acid.

Conclusion: The most common bacteria isolated causing NNS using BACTEC automated blood culture system was Staphylococcus aureus. The empirical antibiotics considered for use at the study site are gentamycin, VA for Gram-positive organisms and CIP, IPM and MEM for Gram-negative organisms. Some of the participants with positive blood culture died. Therefore, there is a need for regular antibiogram profiles in all hospitals offering neonatal care.