Diagnostic utility of combined immature and total neutrophil counts along with C-reactive protein in early detection of neonatal sepsis: A cross-sectional study.

Introduction: A timely diagnosis is critical for management of Neonatal sepsis. Blood Culture is considered to be the "Gold Standard" for its diagnosis, but it has some limitations. In recent times, highly sensitive and specific inflammatory markers like interleukins, ELISA, counter immune-electrophoresis etc. have been in use for its diagnosis. But these are impractical for developing countries, due to their high cost and requirement of sophisticated equipments. A combination of haematological parameters like total leucocyte count (TLC), immature to total neutrophil ratio (I/T ratio), absolute neutrophil count (ANC), platelet count and C-reactive protein (CRP) estimation provide an early diagnosis of bacteremia. This study was undertaken to evaluate the usefulness of the above mentioned parameters as indicators for early diagnosis of neonatal sepsis. Material and methods: In the present cross-sectional study, we intent to analyse various hematologic parameters in 160 neonates admitted in the neonatal care unit of a tertiary care hospital in Delhi. We obtained data from the records of blood culture and complete blood counts of neonates from pathology and microbiology departments of the hospital. Out of 160 admitted neonates, 80 were taken as cases and remaining 80 were taken as controls. Medical records were studied to identify infants born at ≥ 34 weeks gestation. CBCs was analysed, blood cultures and CRP were done in department of Microbiology. CBC, CRP and Blood culture was done as per standard protocols and clinical assesment by paediatrician. The statistical analyses were performed using SPSS version 22 for windows. Results: Among 80 neonates, who were in early neonatal sepsis, 44 cases (55%) were females, and 36 (45%) were males. The Microbiological profile of 80 septic neonates was analysed. The I/T value, ANC and CRP values were significantly higher in the neonates suffering from sepsis as compared to the control group. Among 80 septic neonates (cases), 30 (37.5%) were having normal ANC while 50 (62.5%) were having increased ANC and 34 (42.5%) were having normal I:T ratio while 46 (57.5%) were having increased I:T ratio. Out of 80 septic neonates (cases), 18 (22.5%) were having normal CRP while 62 (77.5%) were having increased CRP. Conclusion: ANC, I/T Ratio and CRP are quick, simple and cost-effective routine laboratory tests which help in early diagnosis of neonatal sepsis. Although there are many serological markers available, ANC and I/T Ratio serves as a reliable predictor of neonatal sepsis. With a good sensitivity, high specificity and a good negative predictive value these parameters can therefore help in timely and early identification of neonatal sepsis.