title: Quality control in QuantiFERON-TB gold in-tube for screening latent tuberculosis infection in health care workers.
abstract: QuantiFERON-TB gold in-tube has been used for screening latent tuberculosis infection in newly employed health care workers in Japan. There have been a few studies concerning quality control. We retrospectively analysed QuantiFERON-TB gold in-tube results in a hospital in Japan. Interferon-γ values in three blood collection tubes for QuantiFERON-TB gold in-tube were analysed in association with the positivity rate. The data set consisted of health care workers aged 20-29 years during the 7 years between 2010 and 2016. The yearly QuantiFERON-TB gold in-tube positivity rate was 0.9%, 16.4%, 3.0%, 39.3%, 2.8%, 0.9% and 1.5%, and was extremely high in 2011 and 2013. The interferon-γ values in the tuberculosis antigen tube were elevated in these two years, as indicated by higher median and wider interquartile range. The interferon-γ value in the negative control tube was also higher in 2011. The higher interferon-γ values in collection tubes (tuberculosis antigen tube and/or negative control tube) resulted in higher QuantiFERON-TB gold in-tube positivity rate. The distribution of interferon-γ in tuberculosis antigen tube and negative control tube, as evaluated by median and interquartile range, proved to be an effective index for the quality control of QuantiFERON-TB gold in-tube.
authors.affiliation: Division of Infection Control, Chiba University Hospital, Japan. Electronic address: hide306@gmail.com.
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Igari
authors.affiliation: Division of Infection Control, Chiba University Hospital, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Watanabe
authors.affiliation: Division of Infection Control, Chiba University Hospital, Japan.
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Ichimura
authors.affiliation: Division of Infection Control, Chiba University Hospital, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Sakurai
authors.affiliation: Division of Infection Control, Chiba University Hospital, Japan.
authors.forename: Toshibumi
authors.initials: T
authors.lastname: Taniguchi
authors.affiliation: Division of Infection Control, Chiba University Hospital, Japan.
authors.forename: Naruhiko
authors.initials: N
authors.lastname: Ishiwada
mesh_terms: D000328:Adult; D006046:Gold; D006282:Health Personnel; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D059425:Interferon-gamma Release Tests / Q000379:methods; D007564:Japan; D055985:Latent Tuberculosis / Q000175:diagnosis* / Q000378:metabolism / Q000382:microbiology*; D008403:Mass Screening / Q000379:methods; D011786:Quality Control; D012189:Retrospective Studies; D014374:Tuberculin Test / Q000379:methods*; D055815:Young Adult
chemical_list: D006046:Gold; D007371:Interferon-gamma
keywords: Health care workers; Latent tuberculosis infection; Quality control; QuantiFERON-TB gold in-tube