Tuberc Respir Dis.  2013 Jul;75(1):18-24.

Prevalence of Latent Tuberculosis Infection among Health Care Workers in South Korea: A Multicenter Study

• Jo KW
• Hong Y
• Park JS
• Bae IG
• Eom JS
• Lee SR
• Cho OH
• Choo EJ
• Heo JY
• Woo JH
• Shim TS

Abstract

BACKGROUND
We investigated the prevalence of latent tuberculosis infection (LTBI) among the health care workers (HCWs) and analyzed its risk factors in South Korea.
METHODS
A standard questionnaire regarding the baseline demographics and risk factors for LTBI was given to each participant and tuberculin skin test (TST), QuantiFERON-TB GOLD In-Tube (QFT-GIT) assay, and chest radiography were performed.
RESULTS
A total of 493 participants, 152 (30.8%) doctors and 341 (69.2%) nurses were enrolled in eight tertiary referral hospitals. The mean age of the subjects was 30.6 years old, and 383 (77.7%) were female. Of the 152 doctors, 63 (41.4%) and 36 (23.7%) were positive by TST and by QTF-GIT, respectively, and among the 341 nurses, 119 (34.9%) and 49 (14.4%) had positive TST and QFT-GIT results, respectively. Overall, the agreement between the two tests was 0.22 by the chance corrected proportional agreement rate (kappa coefficient) in 493 subjects. Experience of working in tuberculosis (TB)-related departments was significantly associated with positive LTBI test results by QFT-GIT assay, not by TST. In multivariate analysis, only age was independently associated with increased risk of a positive TST result, while age and experience of working in TB-related departments (odds ratio, 2.29; 95% confidence interval, 1.01-5.12) were independently associated with increased risk of a positive QFT-GIT result.
CONCLUSION
A high prevalence of LTBI was found among South Korean HCWs. Considering the association between the experience of working in TB-related departments and high risk of LTBI, QFT-GIT may be a better diagnostic test for LTBI than TST in HCWs.

Keyword

Latent Tuberculosis; Health Personnel; Tuberculin Test; Interferon-gamma Release Tests; Republic of Korea

MeSH Terms

Delivery of Health Care
Demography
Diagnostic Tests, Routine
Female
Health Personnel
Humans
Interferon-gamma Release Tests
Latent Tuberculosis
Multivariate Analysis
Prevalence
Surveys and Questionnaires
Republic of Korea
Risk Factors
Skin Tests
Tertiary Care Centers
Thorax
Tuberculin
Tuberculin Test
Tuberculosis
Tuberculin

Figure

• 

  Figure 1 Dot plot of individual results of the tuberculin skin test and QuantiFERON-TB Gold In-Tube (QFT-GIT) of subjects. The dashed line represents the cutoff of 0.35 IU/mL for interferon-gamma. All points below zero among the QTF-GIT results in this figure have been assigned a value of zero.

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