title: Paradoxical reaction during tuberculosis treatment in immunocompetent children: clinical spectrum and risk factors.
abstract: BACKGROUND
  Paradoxical reaction (PR) during antituberculosis (TB) therapy, defined as clinical or radiologic worsening of preexisting TB lesions or the development of new lesions, has not been widely studied in immunocompetent children.
  
  
  METHODS
  All children (<17 years) with the diagnosis of TB who sought care at our center between 1994 and 2007 were included in this retrospective study. Data on demographic characteristics, bacteriologic results, medical imaging, treatment regimens and outcomes were abstracted from medical records. Patients with and without PR were compared.
  
  
  RESULTS
  Of 115 TB cases, 12 (10.3%) developed PR. Children with PR were younger than those with TB without complication: median age at diagnosis was 26 months (range, 5-148) compared with 66 months (range, 6-205) for those without complications (P = 0.013). None of the children in the PR group had received Calmette-Guérin bacillus vaccination, compared with 34 of 103 (33%) children without PR (P = 0.017). Children with a diagnosis of PR were more frequently symptomatic at diagnosis of TB disease when compared with children without PR (P = 0.028). PR occurred at a median interval of 39 days (range, 15-75) after initiation of antituberculosis treatment. The most common PR was worsening of preexisting pulmonary lesions (75%). New lesions in anatomical sites other than those observed at initial presentation developed in 3 children.
  
  
  CONCLUSIONS
  Paradoxical deterioration during treatment of TB disease is common in immunocompetent children. Young age and absence of Calmette-Guérin bacillus vaccination appeared to be associated with PR.
authors.affiliation: Pediatric, Department, CHU Saint-Pierre, Brussels, Belgium.
authors.forename: Carole
authors.initials: C
authors.lastname: Olive
authors.forename: Françoise
authors.initials: F
authors.lastname: Mouchet
authors.forename: Véronique
authors.initials: V
authors.lastname: Toppet
authors.forename: Edwige
authors.initials: E
authors.lastname: Haelterman
authors.forename: Jack
authors.initials: J
authors.lastname: Levy
mesh_terms: D000293:Adolescent; D000995:Antitubercular Agents / Q000627:therapeutic use; D001500:BCG Vaccine / Q000627:therapeutic use; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D018450:Disease Progression; D005260:Female; D006801:Humans; D007121:Immunocompetence; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome; D014376:Tuberculosis / Q000175:diagnosis / Q000188:drug therapy* / Q000276:immunology*
chemical_list: D000995:Antitubercular Agents; D001500:BCG Vaccine