Utility of septic screen in early diagnosis of neonatal sepsis

Abstract

Background and Objectives: (Signs of neonatal sepsis are subtle) and common to various illnesses making the diagnosis of sepsis difficult. Results of isolation of organism and culture are available only after 48 -72 hours. Hence the need to find out different laboratory determinants helpful in detecting neonatal sepsis. A 'septic screen' of the following investigations was evaluated as a reliable indicator of neonatal sepsistotal leukocyte count, absolute neutrophil count, immature to total neutrophil ratio, micro erythrocyte sedimentation rate, C reactive protein.Methods: This study was carried over a period of 18 months in a tertiary care hospital. A total of 250 neonates admitted with a clinical diagnosis of neonatal sepsis were included. Total leukocyte count was performed using an automated cell counter, differential count was done on peripheral smears stained with Wright stain, micro ESR was measured using capillary tubes with an internal diameter of 1.1 mm and length 75mm, CRP was estimated by commercially available latex agglutination kit. The cut off values used were Leukopenia < 5000 cells/mm 3 , neutropenia < 1800/mm 3 , immature neutrophils: total neutrophils count ratio >0.2, microESR >15mm, CRP positive (>1mg/dl) Results: Blood culture was positive in 75 cases (30%) only and the commonest organism cultured was Acinetobacter. On comparing various tests with blood culture as gold standard they were found to be statistically significant (p<0.01) Interpretation and Conclusions: The best three test combination was absolute neutrophil count + I/T ratio + ESR (AIE) having the best specificity and PPV.