Diagnostic and prognostic importance of clinical and laboratory parameters in community-acquired pneumonia
Determining the concentration of procalcitonin and a highly sensitive C-reactive protein in the blood increases the accuracy of the approaches currently used to diagnose community-acquired pneumonia, in addition to clinical symptoms.
Community-acquired pneumonia (CAP) is one of the main causes of infectious death. The diagnosis of this disease is considered the standard for detecting fresh infiltrates during thoracic fluoroscopy under conditions of recently developed acute respiratory symptoms, however, the diagnostic significance of individual clinical symptoms and laboratory parameters in patients with CAP n is not fully understood.
The aim of the study by B. Müller et al. (Switzerland), was to assess the diagnostic and prognostic significance of clinical symptoms and laboratory parameters in community-acquired pneumonia. The work included data from 545 patients over 18 years of age with suspected lower respiratory tract infection who participated in two controlled clinical trials. The initial examination of patients included a history, physical examination, X-ray examination, determination of the concentration of procalcitonin, a very sensitive C-reactive protein and the number of leukocytes in the blood. The authors of the work carried out the construction of characteristic curves (ROC curves), reflecting the importance of various indicators in the diagnosis of PE.
Based on the results of the examination, community-acquired pneumonia was detected in 373 out of 545 patients, other respiratory tract infections in 132 and other diseases in 40. The area under the ROC curve ( CPP) in the PE diagnostic model based on standard clinical symptoms (fever, cough, sputum production, abnormal lung auscultation results and dyspnea) was 0.79 (confidence interval (CI) to 95 % 0, 0.75-0.83). This indicator increased significantly when the results of the determination of the concentration of procalcitonin and a highly sensitive C-reactive protein were included in the assessment (0.92, 95% CI 0.89-0, 94; p less than 0.001). At the same time, the concentration of procalcitonin was of greater importance in the differential diagnosis of VP compared to the concentration of the very sensitive C-reactive protein and the number of leukocytes (PEP 0.88, 95% CI 0, 84-0.93 vs PPC 0.76, 95% CI 0.69-0.83 vs AEC 0.69, 95% CI 0.62-0, 77, respectively; p less than 0.001). In addition, the concentration of procalcitonin in the blood had the highest prognostic significance compared to the development of bacteremia compared to other indicators (AUC 0.85, 95% CI 0.80-0.91; lower p 0.01). An increase in the concentration of procalcitonin with an increase in the severity of community-acquired pneumonia was also noted, in contrast to the concentration of reactive protein C and the number of leukocytes (p less than 0.001).
Thus, the determination of the concentration of procalcitonin and, to a lesser extent, of the highly sensitive C-reactive protein in the blood makes it possible to increase the precision of the approaches currently used to diagnose pneumonia of community origin, in addition to the symptoms. clinics. The concentration of procalcitonin can also be used to assess the severity of the CAP.