Comparison of procalcitonin levels with blood culture results and foci of infection in septic patients.

Abstract

Background and aim: Large number of studies proved undisputable role of procalcitonin (PCT) in sepsis diagnosis. Moreover, potential of procalcitonin to predict blood culture results according to Gram staining, different types of pathogens and foci of infection is discussed lately. The primary aim of our study was to compare the PCT levels in septic patients with documented Gram-positive and Gram-negative bacteraemia. We also evaluated the PCT levels according to different foci of infection and with different types of pathogens.

Material and methods: Procalcitonin levels measured at the time of sepsis diagnosis (PCT1) and after 24 hours (PCT2) in welldefined cohort of septic patients were statistically evaluated according to the results of blood cultures and foci of infection.

Results: Out of 258 patients, 180 had negative and 78 positive blood culture. The difference in PCT1 and PCT2 levels between gram-negative (GN) and gram-positive (GP) bacteraemia was not significant. The highest values of PCT1 as well as PCT2 in culturepositive cases were found in patients infected with Streptococcus spp. followed by Escherichia Coli in contrast to Staphylococcus spp. with the lowest PCT concentrations. Highest procalcitonin levels were observed in urosepsis with PCT2 concentrations significantly higher than in all other foci of infection.

Conclusion: PCT discriminatory power to differentiate between GN and GP bacteraemia in septic patients appears to be low. PCT concentrations correlates probably more closely to different type of pathogens with highest PCT levels in Streptococci spp. and foci of infection rather than result of the Gram stain. In our study population, urosepsis showed statistically significant higher PCT concentrations 24 hours following sepsis diagnosis when compared to other site of infection.