Evaluation of the relationships between procalcitonin and neutrophil/lymphocyte ratio and platelet/lymphocyte ratio in patients with pneumonia.

Abstract

The aim of this study is to examine whether there is a relationship between procalcitonin and neutrophil/lymphocyte ratio or platelet/lymphocyte ratio in patients with pneumonia. The data of 54 patients hospitalized in the respiratory unit of the Adıyaman University Faculty of Medicine Hospital (Adıyaman, Turkey) with the diagnosis of pneumonia between January 2018 and July 2019 were reviewed retrospectively. The patients' complete blood count, procalcitonin, erythrocyte sedimentation rate, and C-reactive protein data were obtained. Diagnosis was made by chest X-ray and, for some patients, by thorax computed tomography together with appropriate clinical findings. Patients with a history of tumors, trauma, burns, surgery, kidney failure, inflammatory diseases or non-pulmonary infections were excluded from the study. The mean age of the patients was 59.04±20.00 years in the group with normal procalcitonin and 66.04±18.28 years in the group with elevated procalcitonin (p: 0.186). The female/male sex ratio of the patients was 15/13 in the group with normal procalcitonin and 8/18 in the group with elevated procalcitonin (p: 0.090). Neutrophil/lymphocyte ratio was 3.97 (1.20-10.77) in the group with normal procalcitonin and 7.21 (0.60-29.50) in the group with elevated procalcitonin (p: 0.012). Platelet/lymphocyte ratio was 155.54±68.89 in the group with normal procalcitonin and 157.48±81.38 in the group with elevated procalcitonin (p: 0.925). In ROC analysis performed to predict elevated levels of procalcitonin, cut-off values were 16.4 ×103/mm3 for white blood cells (p: 0.003), 11.7 ×103/mm3 for neutrophils (p: 0.001), 5.47 for neutrophil/lymphocyte ratio (p: 0.005), and 7.4 mg/dL for C-reactive protein (p: 0.005). In our study, white blood cell, neutrophil, neutrophil/lymphocyte ratio, and C-reactive protein values were found to be significantly higher in patients with elevated procalcitonin. The neutrophil/lymphocyte ratio was also significantly correlated with white blood cell count and platelet/lymphocyte ratio.