Correlation of blood culture results with the sepsis score and the sepsis screen in the diagnosis of neonatal septicemia

Authors:Rekha Sriram
Int J Biol Med Res. 2011; 2(1): 360 – 368  |  PDF File

Abstract

Objectives:To isolate the organism responsible for neonatal septicemia from the blood and to correlate the blood culture results with the Sepsis score and the Sepsis screen parameters. Methods:This prospective study was done over a period of one year. Blood samples from 115 clinically suspected neonatal septicemia cases were subjected to aerobic culture and Sepsis screen tests like C-Reactive protein, micro-ESR, buffy coat smear study, total WBC count, Absolute neutrophil count, Immature/Total neutrophil count (I/T) ratio and platelet count. The culture results were correlated with the Sepsis score and the Sepsis screen tests. Results:Of the 115 cases studied, 50.4% were blood culture positive. 60.3% were males. 37.4% were preterm and 41.3% were very low birth weight neonates. High risk sepsis score was seen in 43.1% cases. Early onset septicemia was more common, seen in 77.6% of cases than late onset septicemia (22.4%) cases. Gram negative organisms accounted for 56.9% of the isolates than Gram positive organisms seen in 41.4% of cases. Klebsiella pneumoniae and Staphylococcus aureus were the commonest organisms isolated in 43.1% and 37.9% of cases respectively. Positive buffy coat smear was the single best reliable sepsis screen test with a high specificity (86.7%) but, the positive predictive value and specificity was high when two or more sepsis screen tests were combined. The mortality rate among the culture positive cases was 46.5% with maximum case fatality seen in the late onset septicemia cases (57.1%). Conclusion:The sepsis scoring system in predicting neonatal septicemia clinically needs further evaluation. Blood culture remains the gold standard for the diagnosis of neonatal septicemia. Combination of two or more sepsis screen parameters has better results in diagnosing neonatal septicemia compared to a single test while awaiting the blood culture results. KEYWORDS: Blood culture, Neonatal septicemia, Sepsis score, Sepsis screen.