Proinflammatory laboratory predictors of pneumonia in ischemic stroke patients: prospective study

Abstract

Background. Bacterial pneumonia is a frequent complication of ischemic stroke at the hospital stage. The search for prognostic laboratory markers of pneumonia remains an urgent task, as it will allow to individualize the approach to the treatment and rehabilitation of such patients. Aim. To investigate the prognostic significance of proteins of the acute phase of inflammation, as well as to evaluate them as early predictors of the development of pneumonia in patients with ischemic stroke. Materials and methods. The study included 302 patients in the acute period of ischemic stroke. C-reactive protein (CRP), tumor necrosis factor , interleukin-6 (IL-6), neutrophil elastase, neopterin, serum amyloid A (SAA), secreted phospholipase type 2 (sPLA2) were determined in all patients on the first day by enzyme immunoassay. Statistical data processing was carried out using SPSS and Microsoft Excel software (USA). Results. At the hospital stage, pneumonia developed in 82/302 patients (27.2%; 95% confidence interval 22.332.3%). The levels of CRP, IL-6, sPLA2, SAA and neopterin significantly differed in the presence and absence of pneumonia. Step-by-step logistic regression analysis revealed the significance of IL-6 and CRP concentrations in the prognosis of pneumonia. The threshold value of IL-6 concentration was 3.45 pg/ml (sensitivity 82.4%, specificity 66.7%). The prognostic value of a positive result (PPR) in the prognosis of pneumonia was 40%, a negative result (PNR) 92%. The threshold value of CRP was 1640 mg/l with a sensitivity of 65.8% and a specificity of 74.8%. The PPR of the threshold value of the concentration of CRP was 45%, PNR 80%. Conclusion. The measurement of the concentration of IL-6 and CRP on the first day of ischemic stroke makes it possible to identify patients with the greatest risk of pneumonia at the hospital stage. The results of the work indicate the necessity to include CRP and IL-6 in the list of mandatory laboratory tests that should be carried out for each patient with ischemic stroke on the first day from the onset of the disease.