Comparative study of C-reactive protein versus procalcitonin as an early marker of neonatal sepsis

Background: Neonatal sepsis is one of the important causes of neonatal morbidity and mortality particularly in the developing countries. In order to avoid unnecessary NICU admissions and antibiotic therapies, it is very important to make early diagnosis of neonatal sepsis with utmost accuracy. Blood culture though gold standard requires lot of time for diagnosis, hence it’s necessary to rely on early diagnostic markers such as blood counts, micro-ESR, CRP, Procalcitonin. Out of the early diagnostic markers available, CRP and pro-calcitonin has the highest sensitivity and specificity rates.Methods: The present study was conducted for a period of one year from January 2014 to December 2014 on neonates admitted to NICU, GSL Medical College, Rajahmundry, Andhra Pradesh, India. Proper consent was taken from the parents of all neonates. Specimens of blood obtained from each neonate with proper aseptic conditions and prior to commencement of antibiotics.Results: Total of 60 neonates satisfying the inclusion criteria are taken in the study group, based on the above criteria, they are grouped into 3 categories, 20/60 neonates had clinical sepsis, 22/60 had suspected sepsis and confirmed sepsis was found in 18/60 neonates. Appropriate investigations were done. Blood culture was positive in 18 neonates. Procalcitonin was negative in 32 neonates, weakly positive (0.5-2ng/ml) in 5 neonates, positive (2-10ng/ml) in 15 neonates, and strongly positive (>10ng/ml) in 7 neonates. Total no. of cases positive for procalcitonin are 28/60. The sensitivity of procalcitonin is 88.88%, specificity is 75%, Positive predictive value is 61.5%, and negative predictive value is 93.75%. PCT is positive in 16/18 blood culture positive cases. CRP was positive in 22/60 cases, and negative in 38/60 cases. CRP was positive in 12/18 blood culture positive cases. The sensitivity of CRP was 66.66%, specificity 76.19%, PPV 54.54%, NPV 84.21%.Conclusions: Higher sensitivity and negative predictive value of PCT, Pro-calcitonin surely scores a way more compared to CRP in early diagnosis of neonatal sepsis.