Tuberculosis contact investigation using interferon-gamma release assay with chest x-ray and computed tomography.
Between September 2009 and January 2010, 6 members of the Japanese Eastern Army, who had completed the same training program, were diagnosed with active tuberculosis (TB) on different occasions. The Ministry of Defense conducted a contact investigation of all members who had come into contact with the infected members. The purpose of this study was to verify the efficacy of the TB screening protocol used in this investigation. A total of 884 subjects underwent interferon-gamma release assay (IGRA) and chest X-ray. The 132 subjects who were IGRA positive or with X-ray findings suggestive of TB subsequently underwent chest computer tomography (CT). Chest CT was performed for 132 subjects. Based on CT findings, 24 (2.7%) subjects were classified into the active TB group, 107 (12.1%) into the latent tuberculosis infection (LTBI) group, and 753 (85.2%) into the non-TB group. The first 2 groups underwent anti-TB therapy, and all 3 groups were followed for 2 years after treatment. Although one subject in the active TB group experienced relapse during the follow-up period, no patient in the LTBI or non-TB groups developed TB. IGRA and chest X-ray, followed by chest CT for those IGRA positive or with suspicious X-ray findings, appears to be an effective means of TB contact screening and infection prevention.
Department of Medical Education and Research, Japan Self-Defense Forces Central Hospital, Ikejiri, Setagaya, Tokyo, Japan ; Department of Radiology, Japan Self-Defense Forces Central Hospital, Tokyo, Japan.
Akira
A
Fujikawa
Department of Internal Medicine, Kawakita General Hospital, Asagaya-kita, Suginami, Tokyo, Japan.
Tatsuya
T
Fujii
Division of Respiratory Medicine, Department of Internal Medicine, Japan Self-Defense Forces Central Hospital, Tokyo, Japan.
Satoshi
S
Mimura
Division of Infectious disease, Department of Internal Medicine, Japan Self-Defense Forces Central Hospital, Tokyo, Japan.
Ryota
R
Takahashi
Division of Respiratory Medicine, Department of Internal Medicine, Japan Self-Defense Forces Central Hospital, Tokyo, Japan.
Masao
M
Sakai
Department of Medical Education and Research, Japan Self-Defense Forces Central Hospital, Ikejiri, Setagaya, Tokyo, Japan ; Division of Respiratory Medicine, Department of Internal Medicine, Japan Self-Defense Forces Central Hospital, Tokyo, Japan.
Shinya
S
Suzuki
Department of Radiology, Japan Self-Defense Forces Central Hospital, Tokyo, Japan.
Yukishige
Y
Kyoto
Department of Internal Medicine, Japan Ground Self-Defense Force Fukuoka Hospital, Kokura-Higashi, Kasuga, Fukuoka, Japan.
Yasuhide
Y
Uwabe
Molecular Epidemiology Division, Department of Mycobacterium Reference and Research, Research Institute of Tuberculosis Japan, Matsuyama, Kiyose, Tokyo, Japan.
Shinji
S
Maeda
Japan Anti-Tuberculosis Association (JATA), Research Institute of Tuberculosis Japan, Matsuyama, Kiyose, Tokyo, Japan.
Toru
T
Mori
D000328:Adult; D016358:Contact Tracing; D006801:Humans; D059425:Interferon-gamma Release Tests; D008875:Middle Aged; D008889:Military Personnel; D013902:Radiography, Thoracic; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed; D014376:Tuberculosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000635:transmission*