Peripheral blood smear can be a reliable and inexpensive alternative to blood culture in early diagnosis of neonatal sepsis

Abstract

Background: Neonatal sepsis is one of the major causes of morbidity and mortality in newborns, more so in the developing countries. Objectives: The aim of this article is to study the role of peripheral smear, to evaluate the usefulness of white blood cell (WBC) parameters, and to establish the sensitivity and specificity of each parameter for early diagnosis of neonatal septicemia. Materials and Methods: The prospective study is of 150 neonates admitted and fulfilling the inclusion criteria, over the period of June 2019 to December 2020, and tests were performed at the Department of Pathology in a tertiary medical college and hospital. Peripheral blood sample was obtained by venipuncture and the sepsis work-up included routine blood counts and blood culture. Total leucocytes counts were counted on an automated hematology analyzer. Leishman-stained peripheral blood smears were used for the study. Results: Based on the clinical findings and laboratory data, neonates were classified into three categories: sepsis (n = 70), probable infection (n = 50), and no infection (n = 30). The blood culture reports of confirmed sepsis cases reveal the commonest organism as Escherichia coli, followed by Klebsiella, Pseudomonas, and beta-hemolytic streptococci. Abnormal I:T ratio (≥0.2) shows highest sensitivity (90%) and specificity (95%). Conclusion: The peripheral smear study is found to be very useful in the early diagnosis of neonatal septicemia as it can be performed even in a small laboratory without any special equipment and within a short period of time. Among WBC parameters, the I:T ratio shows highest sensitivity and specificity.

Keywords

• hematological scoring
• neonatal septicemia
• peripheral smear