Diagnostic Utility of C-Reactive Protein and Permutation Combination of Quantitative and Qualitative Haematological Parameters in Neonatal Sepsis

Introduction: Neonatal sepsis at times is subclinical and lacks specific symptoms. The C-Reactive Protein (CRP) which is an acute phase reactant protein is thought to be an alternative biomarker to blood culture. Haematological parameters of sepsis are indirect biomarkers of infection. Authors found it worthwhile to discern efficacy of haematological parameters obtained by such three part haematology analysers in diagnosis of neonatal sepsis, when used in their pure form or with peripheral blood smear or with CRP, in isolation or in their combinations. Aim: To find out the diagnostic utility of combinations of haematological parameters as obtained by three part differential automated haematology analyser and peripheral blood smear along with CRP in neonatal sepsis. Materials and Methods: This observational and analytical study of diagnostic test outcome was carried out over a period of 12 months from January-December 2016 in Rajarshi Chhatrapati Shahu Maharaj Medical College and Chhatrapati Pramilaraje Rugnalaya, Kolhapur, Maharashtra, India, with special reference to clinical profile, blood culture, qualitative and quantitative haematological parameters and CRP. The statistical analysis included calculating diagnostic utility of isolated and combination of parameters and performing Chi-square test to study difference in frequency of occurrence and significance of association. Results: There were 104 cases of neonatal sepsis out of which culture proven sepsis was seen in 73 (70.2%) cases while probable sepsis was seen in 31 (29.8%) cases. There were 32 (30.8%) fatalities. With parallel method with OR values, combination of haemoglobin, platelet parameters and White Blood Cells (WBC) parameters as obtained by analyser and peripheral blood smear exhibited sensitivity of 98.6%, specificity and Positive Predictive Value (PPV) of 100%, Negative Predictive Value (NPV) of 96.9% and Diagnostic Accuracy (DA) of 99%. This was surpassed by combination of CRP and all these parameters to attend values of 100%. Combination of all haematological parameters obtained purely by analyser showed these values to be 89%, 100%, 79.5% and 92.3%. Immature to Total WBC (I:T) ratio and platelet count influenced clinical outcome of fatality. Conclusion: The liberal use of combination of haematological parameters is rewarding in supporting diagnosis of neonatal sepsis. The same was obtained by purely using analyser which showed remarkable diagnostic utility suitable for resource poor settings.