Study of umbilical cord blood culture in diagnosis of early-onset sepsis among newborns with high-risk factors

Context: Blood culture is gold standard for diagnosis of neonatal sepsis. Low sensitivity of blood culture is usually due to small volume of blood sample, intrapartum antibiotics, and antibiotics given to newborn before sampling. Aim: We evaluated use of Umbilical cord blood culture (UCBC) in diagnosis of neonatal sepsis as compared to peripheral venous blood culture. Settings and Design: This study was done in tertiary care teaching hospital during May-June 2012. A total of 45 newborns with presence of two or more risk factors of sepsis were included. Subjects and Methods: Blood sample from placental end of umbilical cord was collected and cultured. Primary outcome was diagnosis of neonatal sepsis by use of umbilical cord blood sample as compared with venous blood sample. Secondary outcome was to compare organisms identified by UCBC and venous blood culture. Statistical Analysis: Sensitivity, specificity, positive and negative predictive values of UCBC were calculated. Results: A total of 24.44% (11 out of 45) high-risk newborns had positive UCBC. A total of 17.8% (8 out of 45) newborns had positive blood culture report. Organisms grown in UCBC were Pseudomonas (45%, 5 out of 11), Acinetobacter (27.27%, 3 out of 11), Escherichia coli (18.18%, 2 out of 11), and Klebsiella (9%, 1 out of 11). Conclusion: UCBC is a good method for diagnosis of neonatal sepsis among high-risk newborns as compared to venous blood culture with a sensitivity of 80% and specificity of 91.43%. Organisms grown are comparable to blood culture samples.