Umbilical Cord Blood Culture as an Aid to the Diagnosis of Early Onset Neonatal Sepsis: A Cross-sectional Study

Abstract

Introduction: Neonatal sepsis is one of the leading causes of neonatal morbidity and mortality globally, accounting for an estimated neonatal mortality rate of 23.9 per 1000 live births. Due to overlapping signs and symptoms, a specific diagnosis of sepsis poses a diagnostic challenge. Blood collected from a peripheral vein for sepsis screening and blood culture remains the gold standard for diagnosing neonatal sepsis. The umbilical cord is still not routinely used as a site for collecting blood for sepsis screening and blood culture. Aim: To determine the diagnostic efficacy of Umbilical Cord Blood Culture (UCBC) compared to Peripheral Venous Blood Culture (PVBC) in Early Onset Neonatal Sepsis (EONS). Materials and Methods: This cross-sectional observational study was conducted at the Neonatology Unit, Department of Paediatrics, Assam Medical College and Hospital (AMCH), Dibrugarh, Assam, India, involving 110 neonates with two or more risk factors for EONS over a one-year period (August 2021-July 2022). Umbilical cord blood and peripheral venous blood were collected and cultured, and the neonates were monitored throughout their hospital stay. Statistical significance was determined using the Chi-square test for categorical variables and the t-test for continuous variables (with a p-value <0.05 considered statistically significant). The validity of UCBC for diagnosing early neonatal sepsis was assessed based on sensitivity, specificity, Positive Predictive Value (PPV), and Negative Predictive Value (NPV). Results: The mean gestational age was 34.95±3.314 weeks and mean birth weight was 2.08±0.790 grams. Of the 110 high- risk neonates, sepsis screening was positive in 67 (61%), while UCBC and PVBC were positive in 19 (17.3%) and 10 (9.09%), respectively. Acinetobacter was the most common organism found in both cultures. The sensitivity and specificity of sepsis screening were 100% and 47.25% compared to UCBC and 90% and 42% compared to PVBC. In comparison to PVBC, UCBC demonstrated a sensitivity and specificity of 70% and 88%, with a diagnostic accuracy of 86.36%. Conclusion: The UCBC exhibits good diagnostic accuracy for diagnosing EONS and can be utilised due to it being a painless and technically less challenging method of blood sampling, with high sensitivity and specificity.