title: [INCREASE IN THE NUMBER OF INFANTS WITH KOCH PHENOMENON AFTER BCG VACCINATION].
abstract: OBJECTIVE
  To investigate the trends in the number of infants diagnosed with Koch phenomenon after BCG vaccination following the change in the timing of the vaccination.
  
  
  METHODS
  We extracted and analyzed data from infants aged ≤ 1 year diagnosed with latent tuberculosis infection (LTBI) or active tuberculosis, registered in the Japanese tuberculosis surveillance system, from May 2012 to the end of the year, and from May 2013 to the end of the year.
  
  
  RESULTS
  There was no increase in active tuberculosis cases between the two periods (5 patients each). However, the number of infants with LTBI doubled (45 to 90), presumably because Koch phenomenon developed after BCG vaccination.
  
  
  CONCLUSIONS
  After changing the timing of vaccination, the number of infants experiencing Koch phenomenon appears to have increased. However, more in-depth analysis of this finding is required.
authors.forename: Kunihiko
authors.initials: K
authors.lastname: Ito
mesh_terms: D001500:BCG Vaccine / Q000009:adverse effects*; D006801:Humans; D007223:Infant; D055985:Latent Tuberculosis / Q000209:etiology*
chemical_list: D001500:BCG Vaccine