title: Association between bacterial infection and radiologically confirmed pneumonia among children.
abstract: BACKGROUND
  The role of chest radiograph (CXR) among children with community-acquired pneumonia is controversial. We aimed to assess if there is association between a specific etiology and radiologically confirmed pneumonia.
  
  
  METHODS
  This was a prospective cross-sectional study. Based on report of respiratory complaints and fever/difficulty breathing plus the detection of pulmonary infiltrate/pleural effusion on the CXR taken upon admission read by the pediatrician on duty, children <5-year-old hospitalized with community-acquired pneumonia were enrolled. On admission, clinical data and biological samples were collected to investigate 19 etiological agents (11 viruses and 8 bacteria). CXR taken upon admission was independently read by a pediatric radiologist blinded to clinical data.
  
  
  RESULTS
  The study group comprised 209 cases with evaluated CXR and establishment of a probable etiology. Radiologically confirmed pneumonia, normal CXR and other radiographic diagnoses were described for 165 (79.0%), 36 (17.2%) and 8 (3.8%) patients, respectively. Viral infection was significantly more common among patients without radiologically confirmed pneumonia (68.2% vs. 47.9%; P = 0.02), particularly among those with normal CXR (66.7% vs. 47.9%; P = 0.04) when compared with patients with radiologically confirmed pneumonia. Bacterial infection was more frequent among cases with radiologically confirmed pneumonia (52.1% vs. 31.8%; P = 0.02). Likewise, pneumococcal infection was more frequently detected among children with radiologically confirmed pneumonia in regard to children with normal CXR (24.2% vs. 8.3%; P = 0.04). Sensitivity (95% confidence interval) of radiologically confirmed pneumonia for pneumococcal infection was 93% (80-98%), and negative predictive value (95% confidence interval) of normal CXR for pneumococcal infection was 92% (77-98%).
  
  
  CONCLUSIONS
  Bacterial infection, especially pneumococcal one, is associated with radiologically confirmed pneumonia.
authors: From the *Department of Pediatrics and †Department of Image Diagnosis, Federal University of Bahia School of Medicine, Salvador, Brazil; and ‡Department of Pediatrics, University of Turku, Turku, Finland.
authors: Cristiana M
authors: CM
authors: Nascimento-Carvalho
authors: César A
authors: CA
authors: Araújo-Neto
authors: Olli
authors: O
authors: Ruuskanen
mesh_terms: D001424:Bacterial Infections / Q000150:complications / Q000000981:diagnostic imaging* / Q000453:epidemiology* / Q000382:microbiology; D001938:Brazil / Q000453:epidemiology; D002675:Child, Preschool; D017714:Community-Acquired Infections / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000382:microbiology; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011014:Pneumonia / Q000150:complications / Q000000981:diagnostic imaging* / Q000453:epidemiology* / Q000209:etiology; D011446:Prospective Studies; D011859:Radiography