title: [Etiology of community-acquired pneumonia in children hospitalized in the period of 2009-2012].
abstract: OBJECTIVE
  The aim of this study was to analyze etiology of childhood pneumonia in the region of Warsaw and to assess the efficacy and usefulness of standard diagnostic procedures used in search of etiology.
  
  
  METHODS
  663 patients (323 girls and 340 boys) hospitalized due to pneumonia in the period of 2009-2012 were enrolled. Diagnostic procedures to determine the etiology were performed in 400/663 (60.3%) children. Type of diagnostic procedures depended on medical history, disease's course and patient's condition and included 336 blood cultures, 257 measurements of antibody titers against Chlamydophila pneumoniae and Mycoplasma pneumoniae, 12 measurements of antibody titers against Bordetella pertussis, 14 pleural fluid cultures (deriving from 9 patients). Using the BiNet network 51 specimens (45 blood specimens, 4 pleural fluid, 2 bacterial strains) were send to the KOROUN in order to perform molecular diagnostic in search of encapsulated bacteria.
  
  
  RESULTS
  Etiology of pneumonia was found in 9.7% (64/663) of all patients with diagnosed CAP, what accounted for 16% (64/400) of children in which the diagnostics was taken. The most frequent agent was atypical bacteria which was found in 14.75% (59/400) patients (in 26 patients - Chlamydophila pneumoniae, 11 - Mycoplasma pneumoniae, 22 - mixed infection). Bacterial etiology was confirmed in 1.25% (5/400) of patients (Streptococcus pneumoniae-3 patients, Streptococcus pyogenes i Bordetella pertussis - 1 patient each other). Efficacy of a single blood culture was very low - 0.6% (2/336). Pleural fluid culture was positive only in 1 of 9 drained patients (S. pyogenes). Thanks to the use of BiNet network (KOROUN) etiology of severe pneumonia in 3 patients has been determined. 2 of those patients suffered from invasive pneumococcal disease, which was not diagnosed with standard microbiological procedures (blood cultures).
  
  
  CONCLUSIONS
  The methods currently used in the diagnosis of pneumonia is inadequate. It was possible to determine the etiology of only 10% of children hospitalized. The most common cause of pneumonia that seen were atypical infection (8.9%). The effectiveness of single blood culture in determining the etiology of pneumonia was very low and amounted to 0.6%. It is necessary to expand the diagnosis of childhood pneumonia upon the basis of molecular techniques and methods of serotyping.
authors.affiliation: Klinika Pediatrii, Centrum Medyczne Kształcenia Podyplomowego, Marymoncka 99/103, 01-813 Warszawa, tjackowska@cmkp.edu.pl.
authors.forename: Teresa
authors.initials: T
authors.lastname: Jackowska
authors.forename: August
authors.initials: A
authors.lastname: Wrotek