Клинички и етиолошки аспекти на атипичните пневмонии

Abstract

Introduction Pneumonia is an acute inflammation of the lung parenchyma, and can be caused by a variety of microorganisms. Clinically is manifested with increased fever, cough, wheezing and chest tightness. The term "atypical pneumonia" dates back to the early years of the last century and marks the CAP syndrome, with clinical picture and epidemiological characteristics other than those in patients with typical pneumonia. Purpose The main aim of the study is to determine the frequency of certain atypical pathogens as the cause of atypical pneumonia in the adult population and to compare the results of serological and molecular microbiological methods in the aetiological diagnosis of atypical pneumonia. Material and methods The examination is a retrospective-prospective study. In the retrospective part of the study, data from 629 patients treated as atypical pneumonias were analyzed and was made insight into the prevalence of atypical pneumonias, the most common causes, seasonal distribution and distribution of patients by gender, age, nationality, socioeconomic status, place of residence and profession. In the prospective part of the study, 103 patients with atypical pneumonia were analyzed. When setting the aetiological diagnosis, blood samples were taken from all 103 patients. To identify the pathogen, a PneumoSlide® Vircell test was performed, as well as standard laboratory analyzes (sedimentation, blood count with peripheral smear, CRP, AST, ALT, topal, direct and indirect bilirubin). In the three-month follow-up check examination in all 103 patients, blood samples were taken from the PneumoSlide® Vircell test. From patients in whom the results of the serological analysis were positive and had no clinical picture of atypical pneumonia, sputum was taken and in order to identify the pathogen, molecular analyzes of the Seeplex® PneumoBacter ACE Detection Multiplex-PCR System and RV 12 ACE detection were made from the sputum. Results In the retrospective part of the study, the pathogen Legionella pneumophila, with a prevalence of 42.5 %, was proven as the most common cause of atypical pneumonia, and the second most common was Mycoplasma pneumoniae, confirmed in 34.5 % of patients. The most frequent symptoms of the disease were: cough - 98.0 %, wheezing - 96.8 %, fatigue, weakness or malaise - 96 %, temperature - 71.8 % and pain in the chest - 69.8 %. Seasone occurrence was established in atypical pneumonia caused by Legionella pneumophila and Mycoplasma pneumoniae. Patients with atypical pneumonia caused by Legionella pneumophila were significantly older than patients with atypical pneumonia with other causes, while patients with atypical pneumonia caused by Mycoplasma pneumoniae were significantly younger than patients with atypical pneumonia with other causes. In the prospective part of the study, the most common cause was Legionella pneumophila in 40 %, and then Mycoplasma pneumoniae at 35.6 %. In the clinical picture, the dominant symptoms were: cough - 95.6 %, difficulty breathing - 93.3 %, fatigue, weakness or malaise - 91.1 %, temperature higher than 37ºC - 86.7 % and chest pain - 48.9 %. Comparative analysis of certain demographic, clinical and laboratory parameters between Legionella pneumophila and Mycoplasma pneumoniae showed that both causes more often cause atypical pneumonia in men. Younger patients were significantly more infectious with Legionella pneumophila, and older with Mycoplasma pneumoniae (p = 0.023). Comorbidity was significantly more commonly reported in patients with atypical pneumonia caused by Legionella pneumophila (p = 0.044). These patients significantly increased bradycardia, abdominal pain (p = 0.026), nausea (p = 0.0002), elevated AST values (p = 0.025) and ALT (p = 0.011). Testing the diagnostic value of the pneumoslide test, where the molecular method of the PCR was taken as a gold standard, showed that the sensitivity of the pneumoclide to detect Legionella pneumophila was 85 %, the specificity was 96.3 %, and the global test accuracy was 91.5 %. The sensitivity of the pneumoslide test to detect Mycoplasma pneumoniae was 88.9 %, the specificity was 98.8 %, and the global accuracy was 91.7 % Conclusion The most common causes of atypical pneumonia in the patients analyzed in the study were Legionella pneumophila and Mycoplasma pneumoniae. PneumoSlide test is a good diagnostic test in detecting patients with atypical pneumonia. PCR has many attributes that make a useful diagnostic test for pneumonia, but it is an expensive method that is not available in most of the laboratories. Prior to PCR and other methods for amplifying nucleic acid to become routine diagnostic tools, standardized protocols for their use should be established first.