某醫學中心肺結核暴觸者胸部X光篩檢之效益初探

Effectiveness of Pulmonary Tuberculosis Exposure Screening for Health Care Workers in a Medical Center

健康照護者 （HCWs） 因暴觸正處傳染期之開放性肺結核個案而得到感染之盛行率為何？依不同國家及地區其比率相當懸殊，盛行率為每十萬人口6-439人不等。而台灣屬結核病高盛行地區，HCWs 於醫院內暴觸結核病病人的機會增加，本研究以某醫學中心所有通報開放性肺結核之住院病人、HCWs 及肺結核暴觸 HCWs 為研究對象，回溯性調查2005至2007年間暴觸者X光篩檢及例行性X光檢查結果，以探討目前之疫調策略是否可以預測或發現新感染個案，並暸解 HCWs 之肺結核盛行率。研究期間 HCWs 在未經防護下暴觸於開放性肺結核住院病人者共551人次，最後追蹤結果未發現暴觸後感染個案，反而在員工常規X光篩檢及 HCWs 主動就醫發現了肺結核個案，最後確診肺結核之 HCWs 共7人（含開放性肺結核5位），2005至2007年盛行率分別為每十萬人口79（3/3, 809）、46（3/6,493） 及18（1/5,631）人，暴觸後X光篩檢作業並未能達到偵測結核病之效果。結核病防治之重點在如何早期偵測潛在性感染者並早期治療，研究發現暴觸後X光篩檢及咳嗽監測對於發現潛在感染者之效益並不理想，我們認為現行之暴觸者X光追蹤及例行X光篩檢作業應可整合，以簡化現行暴觸者追蹤作業。（感控雜誌 2009; 19: 283-91）。

How high is the prevalence of the infection caused by the exposure of Mycobacterium tuberculosis (TB) patients to health care workers (HCWs) during the infection period? The prevalence of TB is 6 to 439 cases per 100,000 persons, depending on different countries and areas. Taiwan is one of the higher risk area, HCWs are constantly exposed to the higher risk environment. This study is based on all the TB reported patients, HCWs and exposures of TB in a medical center. Through the retrospective study of screening program data and the result of routinely X-ray examination during 2005 to 2007, we find out the possibilities to predict or detect the new infected cases with screening program, and attempt to gain the prevalence of TB among HCWs. The result shows551 HCWs were not infected who were exposed to TB patients without precaution. But the TB cases found in regular X-ray examination and HCWs taking medical treatment by themselves, 7 of the 15,933 workers were diagnosed as TB finally. The prevalence rate was 79、46 and 18 cases per 100,000 employees (2005-2007). Screening strategy didn't reach the expected result. The focus of TB control is early diagnosis of suspected infectious TB, the result of chest radiography and cough monitoring are not satisfied. Current screening program of post exposed and regular X-ray examination should be integrated, to simplify the current exposure follow-up procedure. (Infect Control J 2009;19:283-91).