Evaluation of the Relationship Between the Causative Microorganism and Procalcitonin Levels in Intensive Care Patients

Objective: In intensive care units, various inflammatory and immunological markers, along with the patient's clinic, are used to select the appropriate empirical antibiotic therapy until blood culture results are obtained.Of these markers, C-reactive protein (CRP) and procalcitonin (PCT) are frequently used.Our study aimed to evaluate the relationship between microorganism grown in blood culture and PCT level.Material and Methods: In our study, following the approval of the ethics committee, the demographic data, blood culture growths, and CRP and PCT values of the patients who were followed up with a diagnosis of bloodstream infection in the intensive care unit for a six-month period between 15.11.2022 and 15.05.2023 were recorded retrospectively.Repetitive culture growths and contaminated cultures were excluded from the study.Results: The total number of cultures included in the analysis was 510, of which 172 were Gram-negative, 304 were Gram-positive, and 34 were for fungal infection.When Gram-negative cultures were examined, the most common agents were Escherichia coli (29.0%) and Klebsiella pneumoniae (27.9%), respectively.When we looked at Gram-positive cultures, Staphylococcus hemoliticus (24.7%),Staphylococcus hominis (18.8%) and Staphylococcus auerus (14.4%) were the most common factors, respectively.All fungal cultures consisted of Candida species.When the PCT levels of the groups were examined, it was seen that the values were statistically significantly higher in the Gram-negative bacteria group (p<0.001).In comparisons between groups, CRP levels were found to be statistically higher in the Gram-negative group than in both the Gram-positive and fungal groups (p<0.001,p<0.001, respectively).Conclusion: We think that looking at serum PCT levels will guide us in estimating the agent in choosing the empirical antibiotic therapy that should be started until the culture agent is identified.