title: Using Standardized Interpretation of Chest Radiographs to Identify Adults with Bacterial Pneumonia--Guatemala, 2007-2012.
abstract: BACKGROUND
  Bacterial pneumonia is a leading cause of illness and death worldwide, but quantifying its burden is difficult due to insensitive diagnostics. Although World Health Organization (WHO) protocol standardizes pediatric chest radiograph (CXR) interpretation for epidemiologic studies of bacterial pneumonia, its validity in adults is unknown.
  
  
  METHODS
  Patients (age ≥ 15 years) admitted with respiratory infections to two Guatemalan hospitals between November 2007 and March 2012 had urine and nasopharyngeal/oropharyngeal (NP/OP) swabs collected; blood cultures and CXR were also performed at physician clinical discretion. 'Any bacterial infection' was defined as a positive urine pneumococcal antigen test, isolation of a bacterial pneumonia pathogen from blood culture, or detection of an atypical bacterial pathogen by polymerase chain reaction (PCR) of nasopharyngeal/oropharyngeal (NP/OP) specimens. 'Viral infection' was defined as detection of viral pathogens by PCR of NP/OP specimens. CXRs were interpreted according to the WHO protocol as having 'endpoint consolidation', 'other infiltrate', or 'normal' findings. We examined associations between bacterial and viral infections and endpoint consolidation.
  
  
  RESULTS
  Urine antigen and/or blood culture results were available for 721 patients with CXR interpretations; of these, 385 (53%) had endpoint consolidation and 253 (35%) had other infiltrate. Any bacterial infection was detected in 119 (17%) patients, including 106 (89%) pneumococcal infections. Any bacterial infection (Diagnostic Odds Ratio [DOR] = 2.9; 95% confidence Interval (CI): 1.3-7.9) and pneumococcal infection (DOR = 3.4; 95% CI: 1.5-10.0) were associated with 'endpoint consolidation', but not 'other infiltrate' (DOR = 1.7; 95% CI: 0.7-4.9, and 1.7; 95% CI: 0.7-4.9 respectively). Viral infection was not significantly associated with 'endpoint consolidation', 'other infiltrate,' or 'normal' findings.
  
  
  CONCLUSIONS
  'Endpoint consolidation' was associated with 'any bacterial infection,' specifically pneumococcal infection. Therefore, endpoint consolidation may be a useful surrogate for studies measuring the impact of interventions, such as conjugate vaccines, against bacterial pneumonia.
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Jonathan M
authors.initials: JM
authors.lastname: Wortham
authors.affiliation: Universidad del Valle de Guatemala, Guatemala City, Guatemala.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Gray
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Jennifer
authors.initials: J
authors.lastname: Verani
authors.affiliation: Universidad del Valle de Guatemala, Guatemala City, Guatemala.
authors.forename: Carmen Lucia
authors.initials: CL
authors.lastname: Contreras
authors.affiliation: Universidad del Valle de Guatemala, Guatemala City, Guatemala.
authors.forename: Chris
authors.initials: C
authors.lastname: Bernart
authors.affiliation: Universidad del Valle de Guatemala, Guatemala City, Guatemala.
authors.forename: Fabiola
authors.initials: F
authors.lastname: Moscoso
authors.affiliation: Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala.
authors.forename: Juan Carlos
authors.initials: JC
authors.lastname: Moir
authors.affiliation: Ministerio de Salud Pública y Asistencia Social, Guatemala City, Guatemala.
authors.forename: Emma Lissette
authors.initials: EL
authors.lastname: Reyes Marroquin
authors.affiliation: Universidad del Valle de Guatemala, Guatemala City, Guatemala.
authors.forename: Rigoberto
authors.initials: R
authors.lastname: Castellan
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Wences
authors.initials: W
authors.lastname: Arvelo
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America.
authors.forename: Kim
authors.initials: K
authors.lastname: Lindblade
authors.affiliation: Universidad del Valle de Guatemala, Guatemala City, Guatemala.
authors.forename: John P
authors.initials: JP
authors.lastname: McCracken
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006166:Guatemala; D006801:Humans; D008297:Male; D008875:Middle Aged; D011008:Pneumococcal Infections / Q000000981:diagnostic imaging*; D018410:Pneumonia, Bacterial / Q000000981:diagnostic imaging*; D011857:Radiographic Image Interpretation, Computer-Assisted; D013902:Radiography, Thoracic; D012141:Respiratory Tract Infections / Q000000981:diagnostic imaging*; D055815:Young Adult