Utility of Procalcitonin Over C-Reactive Protein and WBC as an Early and Rapid Diagnostic Marker of Bacterial Infections in Febrile Patients with or no Hemoculture Results as Gold Standard in a Malaria Endemic Zone of Cameroon

Abstract

Background & objectives: Early identification of bacterial infection in patients with fever is important for prompt and specific treatment. However, the available biomarkers such as C-reactive protein (CRP) and leukocyte counts are not specific to bacterial diagnosis. This study aimed to assess the diagnostic value of procalcitonin (PCT) over CRP and leukocyte counts for bacterial infection screening in febrile patients while awaiting their hemoculture results, which takes up to 7 Days before results are available though it is the gold standard for the diagnosis of bacterial infections. Methods: Blood samples were collected from febrile patients between January and July 2020 then processed for blood cultures. PCT, CRP and WBC levels were measured. The patients were divided into two groups according to the final diagnosis: bacterial infection group (group1) and non-bacterial infection group (group 2).SPSS version 20.0 software package was used for data analysis and normally distributed variables were calculated using mean, standard deviation and ANOVA test while median and range were used for variables without a normal distribution. Significance testing was done using Kruskal-Wallis h test and Wilcoxon two sample test and the diagnostic accuracy was assessed by calculating the area (AUC) under the receiver operating characteristic curve (ROC). Results: There were significant (P<0.05) difference in the levels of PCT, CRP and WBC among the two groups. The PCT levels of patients in the bacterial infections group were significantly higher than those in the nonbacterial infections group (27.9 vs., 11.7 P < 0.001). The best cut-off value to detect bacterial infections was 1.46 ng/ml for PCT. PCT, CRP and WBC had areas under the curve of 0.71, 0.66 and 0.45 respectively and sensitivity of 100%, 72.7% and 27.3% respectively. Interpretation & conclusions: Our results showed that PCT was a valuable marker for the early and rapid diagnosis of bacterial infections in febrile patients in our setting when compared to CRP and WBC. However, prospective and large scale studies are warranted to confirm these findings in Cameroon.