Background: Neonatal septicaemia refers to a generalized bacterial infection in the first four weeks of life. It can be divided into two types: Early onset neonatal septicaemia (EONS) and Late onset neonatal septicaemia (LONS). The diagnosis can be confirmed by blood culture examination, but various haematological tests can positively predict the diagnosis and the results are available immediately. 

Objective: To evaluate variation in haematological parameters in neonatal septicaemia against blood culture results and to study the difference in results in EONS and LONS and its comparison with C-reactive protein (CRP) for diagnosis.

Materials and Methods: A total of 60 neonates with culture positive septicaemia were studied. Haematological tests like haemoglobin, total leukocyte count, differential leukocyte count, toxic granules, band cells, immature and mature neutrophils, total neutrophil count, platelet count, and CRP were performed. The Haematological Scoring System (HSS) formulated by Rodwell et al was used to calculate the cut off value for the diagnosis.

Results: Out of various haematological parameters, total neutrophil count (75%), ratio of immature to total neutrophils (I/T ratio) (71.7%) and platelet count (60%) were significantly positive in septicaemia. The Haematological score was >3 in 76.6% of newborns. The CRP was positive in 75% of cases. The combined sensitivity of HSS and CRP was 90%. 

Conclusions: Various haematological parameters can be easily performed and when properly interpreted along with their cut off value, as suggested in the study, it can aid in early recognition of neonatal septicaemia against the culture examination. This will save time, money and many a times life of a neonate.

Keywords: Neonatal, septicaemia, haematological tests, C - reactive protein.