Positive tuberculin skin tests in nursing home residents in Southern Taiwan.
In Taiwan, the tuberculin skin test (TST) is not recommended as a screening test for Mycobacterium tuberculosis (TB) infections. The aim of this study is to determine the prevalence and predictors of positive tuberculin reactivity and its association with TB infections among nursing home residents in Taiwan. A cross-sectional study and review of medical records were conducted at four nursing homes in Tainan City. A one-stage TST was performed by study nurses using two tuberculin units of purified protein derivative (PPD) of the RT23 strain. An induration ≥10 mm at 72 h was considered to be a positive reaction. Chest radiographs, acid-fast stains and mycobacterial cultures of three sputum samples were performed for those with a positive TST result. Of 115 residents (66.5% participation, mean age 73.1 years) who underwent a TST, 26 (22.6%) had a positive reaction. One woman was microbiologically diagnosed to have pulmonary TB. On multivariate analysis, a Bacille Calmette-Guérin (BCG) scar and a history of myocardial infarction were significantly associated with a positive TST. In conclusions, this study shows a considerable rate of positive TST among nursing home residents in southern Taiwan. A BCG scar and a history of myocardial infarction were associated with a positive TST.
Chang
Chia-Ming
CM
Division of Geriatrics and Gerontology, Department of Internal Medicine, National Cheng Kung University Hospital, No. 138, Sheng Li Road, Tainan 70403, Taiwan.
Lee
Nan-Yao
NY
Lee
Hsin-Chun
HC
Wu
Chi-Jung
CJ
Chen
Po-Lin
PL
Lee
Ching-Chi
CC
Shih
Hsin-I
HI
Ko
Wen-Chien
WC
D000368:Aged; D016009:Chi-Square Distribution; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D009203:Myocardial Infarction / Q000150:complications; D009735:Nursing Homes; D011237:Predictive Value of Tests; D015995:Prevalence; D012307:Risk Factors; D018709:Statistics, Nonparametric; D013624:Taiwan / Q000453:epidemiology; D014374:Tuberculin Test; D014376:Tuberculosis / Q000453:epidemiology*