title: A prospective cohort study of latent tuberculosis in adult close contacts of active pulmonary tuberculosis patients in Korea.
abstract: OBJECTIVE
  The objective of this prospective study was to evaluate the diagnosis and treatment of latent tuberculosis infection (LTBI) in adult close contacts of active pulmonary tuberculosis (TB) patients in Korea.
  
  
  METHODS
  Adult close contacts of active pulmonary TB patients were recruited at a regional tertiary hospital in Korea. The participants were tested for LTBI using the tuberculin skin test (TST) and/or QuantiFERON-TB Gold (QFT-G) test. LTBI patients, who consented to treatment, were randomly assigned to receive isoniazid for 9 months (9INH) or rifampin for 4 months (4RIF).
  
  
  RESULTS
  We examined 189 adult close contacts (> 18 years) of 107 active pulmonary TB patients. The TST and QFT-G were positive (≥ 10 mm) in 75/183 (39.7%) and 45/118 (38.1%) tested participants, respectively. Among 88 TST or QFT-G positive LTBI participants, 45 participants were randomly assigned to receive 4RIF (n = 21) or 9INH (n = 24), respectively. The average treatment duration for the 4RIF and 9INH groups was 3.3 ± 1.3 and 6.1 ± 2.7 months, respectively. Treatment was completed in 25 participants (4RIF, n = 16; 9INH, n = 9). LTBI participants who accepted treatment were more likely to be women and have more cavitary lesions on the chest radiographs of index cases and positive TST and QFT-G results compared to those who refused treatment.
  
  
  CONCLUSIONS
  About 40% of adult close contacts of active pulmonary TB patients had LTBI; about 50% of these LTBI participants agreed to treatment.
authors.affiliation: Department of Internal Medicine, Dongnam Institute of Radiological & Medical Sciences Cancer Center, Busan, Korea.
authors.forename: Sun Hyo
authors.initials: SH
authors.lastname: Park
authors.affiliation: Department of Internal Medicine, Gyeongsang National University School of Medicine, Jinju, Korea.
authors.forename: Seung Jun
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Gyeongsang National University School of Medicine, Jinju, Korea.|Gyeongsang Institute of Health Sciences, Gyeongsang National University, Jinju, Korea.
authors.forename: Yu Ji
authors.initials: YJ
authors.lastname: Cho
authors.affiliation: Department of Internal Medicine, Gyeongsang National University School of Medicine, Jinju, Korea.|Gyeongsang Institute of Health Sciences, Gyeongsang National University, Jinju, Korea.
authors.forename: Yi Yeong
authors.initials: YY
authors.lastname: Jeong
authors.affiliation: Department of Internal Medicine, Gyeongsang National University School of Medicine, Jinju, Korea.|Gyeongsang Institute of Health Sciences, Gyeongsang National University, Jinju, Korea.
authors.forename: Ho Cheol
authors.initials: HC
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Gyeongsang National University School of Medicine, Jinju, Korea.|Gyeongsang Institute of Health Sciences, Gyeongsang National University, Jinju, Korea.
authors.forename: Jong Deog
authors.initials: JD
authors.lastname: Lee
authors.affiliation: Korean Institute of Tuberculosis, Seoul, Korea.
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Montreal Chest Institute, McGill University, Montreal, QC, Canada.
authors.forename: Dick
authors.initials: D
authors.lastname: Menzies
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000995:Antitubercular Agents / Q000008:administration & dosage*; D016358:Contact Tracing; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D059425:Interferon-gamma Release Tests; D007538:Isoniazid / Q000008:administration & dosage*; D055985:Latent Tuberculosis / Q000175:diagnosis* / Q000188:drug therapy* / Q000382:microbiology / Q000635:transmission; D008297:Male; D055118:Medication Adherence; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D056910:Republic of Korea; D012293:Rifampin / Q000008:administration & dosage*; D062606:Tertiary Care Centers; D013997:Time Factors; D016896:Treatment Outcome; D014374:Tuberculin Test; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000188:drug therapy* / Q000382:microbiology / Q000635:transmission; D055815:Young Adult
chemical_list: D000995:Antitubercular Agents; D007538:Isoniazid; D012293:Rifampin
keywords: Isoniazid; Latent tuberculosis; Rifampin; Tuberculin test; Tuberculosis, pulmonary