title: Serial interferon-γ release assay in children with latent tuberculosis infection and children with tuberculosis.
abstract: BACKGROUND
  Interferon-γ (IFN-γ) release assay (IGRA) is used for diagnosis of latent tuberculosis infection (LTBI), and for serial testing of active tuberculosis (TB). The aim of this study was to evaluate the results of IGRA for diagnosis and treatment monitoring of children with LTBI and children with TB. IGRA was performed in BCG vaccinated children before and six months after the beginning of treatment.
  
  
  METHODS
  A total of 59 BCG vaccinated children aged 4-18 years were investigated due to exposure to active TB. The participants were divided into two groups: Group 1, children with LTBI (N = 41), and Group 2, children with TB (N = 18). IGRA (QuantiFERON-TB Gold In-Tube) was performed twice, i.e., before treatment and at the end of prophylaxis and therapy.
  
  
  RESULTS
  There was no significant difference in IFN-γ concentrations between Group 1 and Group 2 subjects either before or after the treatment. Difference between pre-treatment and post-treatment IFN-γ concentrations compared in either Group 1 or Group 2 was not statistically significant. During follow-up, children with LTBI did not develop active TB. In addition, in children with TB, signs and symptoms of TB improved with anti-TB therapy.
  
  
  CONCLUSIONS
  This study showed that the concentrations of IFN-γ did not differ in children with LTBI and TB either before or at the end of treatment. IGRA may remain positive over a long period of time. It seems that IGRA is not useful for monitoring treatment of children with LTBI and children with TB.
authors: Srebrnjak Children's Hospital, Srebrnjak 100, Zagreb, Croatia. natasanenadic@gmail.com
authors: Nataųa
authors: N
authors: Nenadić
authors: Branka Kristić
authors: BK
authors: Kirin
authors: Ivka Zoričić
authors: IZ
authors: Letoja
authors: Davor
authors: D
authors: Plavec
authors: Renata Zrinski
authors: RZ
authors: Topić
authors: Slavica
authors: S
authors: Dodig
mesh_terms: D000293:Adolescent; D000995:Antitubercular Agents / Q000627:therapeutic use; D001500:BCG Vaccine / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D059425:Interferon-gamma Release Tests; D055985:Latent Tuberculosis / Q000175:diagnosis*; D008297:Male; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000188:drug therapy / Q000517:prevention & control
chemical_list: D000995:Antitubercular Agents; D001500:BCG Vaccine