Comparison of Serum Procalcitonin With Blood Culture (Gold Standard) For the Identification of Bacterial Infection in Critically Ill Patients

Abstract

Background: To evaluate the determinative correctness of Procalcitonin ( PCT )  for  identification  of  bacterial sepsis (gram positive  and  gram negative bacterial infection ) in seriously morbid subjects  who  will  get  admission  in  ICU/emergency  deptt.  of   Khyber teaching hospital  and  comparing it with  blood cultures (gold standard )  .

Methodology: It was a cross-sectional study carried out in ICU /emergency deptt. of Khyber teaching hospital Peshawar  from  March 2019  to  August  2019. A total of 75 patients including  51 patients   having  blood   culture positive and  24 patients  having  blood  culture negative  were  selected through  non – probability consecutive  sampling  technique.

Results: In our study, mean evels were significantly higher for blood culture positive than for blood culture negative cases (p value 0.000) . Cut off level of serum PCT for identification of bacterial sepsis was  0.5ng/ml in critically ill patients . Plasma  PCT   levels  have  sensitivity, specificity, PPV  and  NPV  of 92% , 80% , 90.2% , and  83.3%  respectively in determining blood culture positive than blood culture negative patients . Furthermore it was revealed that PCT   had an (AUC =0.97) for culture positive cases and had  an (AUC= 0.025) for blood culture negative cases.
Conclusion: Sensitivity for PCT  is  greater  than specificity , so  serum PCT  assay is a useful screening  test  and  also  a quick  indicator  of  bacterial  sepsis  in  critically  ill  patients.