Utility of dual skin tests to evaluate tuberculin skin test reactions of 10 to 14 mm in healthcare workers.

OBJECTIVE: To define the utility of 10- to 14-mm reactions to a Mycobacterium tuberculosis purified protein derivative (PPD) skin test for healthcare workers (HCWs). DESIGN: Blinded dual skin testing, using PPD and M. avium sensitin, of HCWs at a single medical center who had a 10- to 14-mm reaction to PPD when tested by personnel from the Occupational Health Department as part of routine annual screening. SETTING: A single tertiary-care academic medical center. PARTICIPANTS: Employees of the medical center who underwent routine annual PPD screening and were identified by the Occupational Health Department as having a reaction of 10 to 14 mm to PPD. RESULTS: Nineteen employees were identified as candidates and 11 underwent dual skin testing. Only 4 (36%) had repeat results for PPD in the 10- to 14-mm range, whether read by Occupational Health Department personnel or study investigators. For only 5 (45%) of the subjects did the Occupational Health Department personnel and study investigators concur (+/- 3 mm) on the size of the PPD reaction. Two of the 4 subjects with reactions of 10 to 14 mm as measured by the study investigators were M. avium sensitin dominant, 1 was PPD dominant, and 1 was nondominant. CONCLUSION: A reaction of 10 to 14 mm to PPD should not be used as an indication for the treatment of latent tuberculosis (TB) infection in healthy HCWs born in the United States with no known exposure to TB.     

1486名结防机构医务人员结核病感染现状调查

目的了解河南省结核病防治机构不同岗位医务人员结核病感染现状。方法于2005年1月从该省18个地市和109个县中随机抽取40个县,对抽取的58个结核病防治机构的所有在职医务人员作为调查对象;进行PPD皮试检查。结果 1 486名医务人员接受了PPD皮试检查,阳性率为66.1%,其中住院医生(75.9%)、门诊医生(75.3%)、住院护理(74.6%)、放射人员(72.3%)、督导医生(71.8%)。经x2检验,PPD皮试阳性率与强阳性率医务人员均明显高于非医务人员。结论该省结防工作人员结核病感染率较高,应加强医务人员的感染控制工作。     

Evaluation of a western blot test as a potential screening tool for occupational exposure to Mycobacterium tuberculosis in health care workers

Health care workers (HCWs) have a higher than average risk for contracting Mycobacterium tuberculosis (MTB) infection and tuberculosis (TB). No markers of MTB-exposure are available, and TB risk assessment is performed by tuberculin screening, identifying individuals with acquired MTB infection. This study evaluated a western blot (WB) anti-M. bovis A60 complex antibody as a MTB-exposure marker. WB reactivity was evaluated on 127 exposed and 28 non-exposed HCWs from four divisions of the Policlinico Hospital of Modena, and 140 non-exposed bacille Calmette-Guérin-vaccinated controls. Excess of occupational TB risk according to the Occupational Safety and Health Administration (OSHA) was calculated in each division. WB-positivity (%) was: (1) significantly higher in exposed HCWs compared with non-exposed (72% vs 25%, P < 0.00001), (2) highly related (r = 0.99) to OSHA risk excess in all divisions, (3) higher than non-exposed in HCWs with short (< 5 years) MTB-exposure (purified protein derivative [PPD], P > 0.18; WB, P < 0.04). PPD-positivity (%) was higher than controls only in HCWs with longer (> 5 years) MTB-exposure. The study suggests that the WB antibody might represent a more sensitive biological marker of MTB contact among exposed HCWs, related to the level of TB risk and detectable earlier than the PPD skin test, thus providing new tools for TB risk assessment in health care facilities.     

结核病专科医院医务人员结核感染风险研究

目的 探讨结核病专科医院医务人员职业暴露危险因素,以采取有效地预防控制措施降低结核感染风险.方法 采用整群抽样的方法,进行问卷调查,采集基本信息,对受试人群进行结核菌素试验(PPD)和T细胞斑点试验(T-SPOT.TB)检测.结果 共有符合条件的497人纳入本研究,98.59％认为自己在工作中有机会接触结核病患者,81.89％工作时佩戴口罩,82.70％接种过卡介苗;受试者中,PPD试验阳性率为66.60％,T-SPOT.TB试验阳性率较低,为10.87％,两种试验结果在医院内不同职业人群间差异无统计学意义,PPD试验阳性率与工作年限有相关性(x2=11.1936,P=0.0107),而T-SPOT.TB试验结果与工作年限无明显相关.结论 加强全体医务人员,特别是行政管理人员和新上岗医务人员的个人防护和健康教育有重要意义.     

Frequency of Mycobacterium tuberculosis infection among Iranian patients with HIV/AIDS by PPD test

Persons infected with the Human Immunodeficiency Virus (HIV) are particularly susceptible to tuberculosis, either by latent infection reactivation or by a primary infection with rapid progression to active disease. This study was done to determine the frequency of tuberculosis infection among Iranian patients with HIV/AIDS. A total of 262 HIV/AIDS patients attending all three HIV/AIDS health care centers of Tehran, Iran were enrolled in this study. A detailed history and physical examination were obtained from all HIV patients suspected of having pulmonary M. tuberculosis. A positive PPD skin test was used as a diagnostic parameter for probability of TB infection. Out of 262 HIV/AIDS patients, a total of 63 (24%) were shown to have the tuberculosis infection based on a positive PPD skin test. Of the patients with positive PPD skin test, 22 (35%) had pulmonary Tuberculosis, 2 (3.2%) had extrapulmonary tuberculosis, and 39 (53%) had no evidence of M. tuberculosis infection (latent infection). Also 8 (12.7%) had history of long term residence in a foreign country, 32 (50.8%) were exposed to an index case, and 9 (14.3%) had past history of pulmonary tuberculosis, while only 33.3% had clinical manifestations of TB (active disease). There was no resistant case of tuberculosis. Our study showed that near 24% of Iranian patients with HIV/AIDS were infected with M. tuberculosis. This finding denotes the need to improve the diagnostic and preventive measures, and also prompt treatment of this type of infection in the HIV infected individuals.     

Tuberculin skin test conversion among medical students at a teaching hospital in Rio de Janeiro, Brazil.

OBJECTIVE: To describe the cumulative incidence of and risk factors for tuberculosis (TB) infection among medical students. DESIGN: In 1999, a cohort study of medical students with negative results (induration < 10 mm) on tuberculin skin test (TST) was performed. Students who had undergone two-step testing in 1998 were retested. SETTINGS: University and teaching hospital and referral center for TB and acquired immunodeficiency syndrome, and the Health Sciences Building of the Medical School of the Federal University of Rio de Janeiro, Brazil. PARTICIPANTS: A sample of 618 consecutive medical students with negative TST results who had been tested 12 months before were approached. Information about sociodemographic characteristics, bacille Calmette-Guérin vaccination history, and potential exposures to TB was obtained using a standardized questionnaire. Four hundred fourteen (67%) students completed the study. Students were at two different levels of their training programs (juniors = no contact with patients; seniors = intensive contact with patients). RESULTS: Of 414 participants, 16 (3.9%; 95% confidence interval, 1.06% to 12.1%) had converted to a positive reaction after 1 year. In a multivariate logistic regression analysis, higher level of clinical training was confirmed to be an independent factor associated with TST conversion (odds ratio, 4.77; 95% confidence interval, 1.01 to 22.46; P= .048). CONCLUSION: Senior medical students are at increased risk of Mycobacterium tuberculosis infection in this setting. Therefore, a program of routine tuberculin skin testing and specific TB infection control guidelines are needed for this population.     

Tuberculosis and HIV co-infection in healthcare workers in England and Wales, 1999-2005

This study used linked national tuberculosis (TB) and HIV surveillance data to investigate recent trends and factors associated with HIV co-infection (TB-HIV) in healthcare workers (HCWs) with TB in England and Wales. Methods applied were the χ2 trend test and logistic regression. Overall 14% (231/1627) of HCWs with TB were co-infected with HIV, increasing from 8% in 1999 to 14% in 2005 (P<0·001). Most (78%) HCWs were non-UK born and 74% of these developed TB ?2 years post-entry. Being born in Sub-Saharan Africa was an independent predictor for TB-HIV, especially for female HCWs (odds ratio 66·5, 95% confidence interval 16·3-271·1), who also had a lower median CD4 count than other co-infected women (106/mm3, interquartile range 40-200, P<0·01). Voluntary HIV testing of new HCWs should be encouraged as an opportunity for early diagnosis. Post-entry, a high index of clinical suspicion for TB in those most at risk remains important.     

Tuberculosis screening programme using the QuantiFERON-TB Gold test and chest computed tomography for healthcare workers accidentally exposed to patients with tuberculosis

Healthcare workers (HCWs) have an increased incidence of tuberculosis (TB). Periodic and as-needed screenings of HCWs exposed to patients with TB are important. We integrated chest computed tomography (CT) and the QuantiFERON-TB Gold (QFT-G) test into our TB screening programme for HCWs. First, contacts were tested using the QFT-G test. Those positive for the QFT-G test were investigated by CT and classified as having active, latent (LTBI), or old TB. Between April 2005 and April 2010, 11 patients who had not been diagnosed with active TB on admission were found to have the disease. A total of 512 close or high risk contacts were identified, and underwent screening. Out of those, 34 (6.64%) were QFT-G positive, whereas 478 (93.36%) were negative. Of the 34 QFT-G-positive HCWs, four had CT findings compatible with active TB and received multidrug treatment; 24 showed no findings of active TB and received isoniazid for six months. All completed their regimens without any adverse effects. The TB screening programme integrating CT and the QFT-G test was safe and feasible. The efficacy of the programme needs to be confirmed by large scale clinical trials.     

Screening for tuberculosis among 2381 household contacts of sputum-smear-positive cases in The Gambia

Contact investigation is a key component of tuberculosis (TB) control in developed, but not developing, countries. We aimed to measure the prevalence of TB among household contacts of sputum-smear-positive TB cases in The Gambia and to assess the sensitivity of an enzyme-linked immunospot (ELISPOT) assay in this regard. Household contacts of adult smear-positive TB patients were assessed by questionnaire, purified protein derivative (PPD) skin test, ELISPOT assay, physical examination, chest X-ray and sputum/gastric aspirate. Thirty-three TB cases were identified from 2174 of 2381 contacts of 317 adult smear-positive pulmonary TB patients, giving a prevalence of 1518/100000. The cases identified tended to have milder disease than those passively detected. The sensitivity of ESAT-6/CFP-10 ELISPOT test as a screening test for TB disease was estimated as 71%. Fifty-six per cent of contacts with a PPD skin test result >or=10mm induration had detectable responses to ESAT-6/CFP-10 by ELISPOT; 11% with a negative PPD skin test (<10mm) had a positive ESAT-6/CFP-10 response. Active screening for TB among contacts of TB patients may have a role in TB control in The Gambia. These individuals are a high-risk group, and the disease identified is less advanced than that found through passive case detection. An ELISPOT assay was relatively insensitive as a screening test for TB.     

Prevalence of tuberculin skin test positivity and conversions among healthcare workers in New York City during 1994 to 2001.

OBJECTIVE: To determine the prevalence of and risk factors for tuberculin skin test positivity and conversion among New York City Department of Health and Mental Hygiene employees. DESIGN: Point-prevalence survey and prospective cohort analysis. Sentinel surveillance was conducted from March 1, 1994, to December 31, 2001. PARTICIPANTS: HCWs in high-risk and low-risk settings for occupational TB exposure. RESULTS: Baseline tuberculin positivity was 36.2% (600 of 1,658), 15.5% (143 of 922) among HCWs born in the United States, and 48.5% (182 of 375) among HCWs not born in the United States. There were 36 tuberculin conversions during 2,754 observation-years (rate, 1.3 per 100 person-years). For HCWs born in the United States, the risk for tuberculin conversion was greater in high-risk occupational settings compared with low-risk settings (OR, 5.7; CI95, 1.7-19.2; P < .01). HCWs not born in the United States and those employed at the Office of the Chief Medical Examiner (OCME) were at high risk for baseline tuberculin positivity (OR, 3.2; CI95, 1.7-5.8; P < .001); OCME HCWs (OR, 4.7; CI95, 2.3-9.4; P < .001), those of Asian ethnicity (OR, 4.3; CI95, 1.4-13.5; P < .01), and older HCWs (OR, 1.0; CI95, 1.0-1.1; P < .05) were at a higher risk for conversion. CONCLUSIONS: Although the prevalence of tuberculin positivity decreased after the peak of the recent TB epidemic in New York City, the conversion rate among HCWs in high-risk occupational settings for TB exposure was still greater than that among HCWs in low-risk settings. Continued surveillance of occupational TB infection is needed, especially among high-risk HCWs.     

2019年北京市朝阳区高中及以下阶段新生入学肺结核筛查结果分析

目的 分析北京市朝阳区高中及以下阶段新生入学肺结核筛查结果,为学校结核病防控工作提供参考依据。 方法 幼儿园、小学、非寄宿制初中新生首先完成肺结核可疑症状问卷调查,有可疑症状者需进行结核菌素皮肤试验（PPD试验）,PPD强阳性或未完成PPD试验者再进一步完成X线胸片检查。高中及寄宿制初中新生均需完成问卷调查和PPD试验,有可疑症状或PPD强阳性或未完成PPD试验者再进行X线胸片检查。 结果 2019年北京市朝阳区550所学校完成了新生肺结核筛查。问卷调查70 835人,有结核病可疑症状者109人,可疑症状率1.54‰,高中（9.36‰）高于幼儿园（0.55‰）、小学（0.63‰）、初中（0.69‰）。PPD试验8 567人,强阳性104人,强阳性率为1.21%,高中组（1.33%）高于幼小初中组（0.64%）,差异有统计学意义（x2=4.72, P =0.03）。X线胸片检查461人,影像学异常9人（全部为高中学生）,其中1名女生诊断为活动性肺结核。 结论 新生入学肺结核筛查工作具有重要意义,应加强高中学生的结核病防控管理工作。     

Drive-by readings: a creative strategy for tuberculosis control among immigrants

OBJECTIVES: We explored an innovative strategy for targeted testing and disease management among immigrant communities at risk for tuberculosis. METHODS: Taxi drivers were recruited at an airport holding lot to undergo tuberculin skin testing (Mantoux). After receiving their test results in a location convenient for them, drivers with positive results were referred for evaluation and treatment. We conducted baseline and follow-up assessments. RESULTS: Of 123 drivers who participated, two thirds (82) were at high risk for tuberculosis. Seventy-eight (63%) of the 123 returned for test readings; 62% of these drivers had positive test results. All drivers with positive results received a complete physician evaluation, but 64% of those evaluated were not treated for latent TB infection. Of the untreated drivers, 37.5% were at high risk. Systemic and physician barriers (e.g., lack of knowledge, erroneous beliefs regarding vaccines) affected adherence to evaluation and treatment. CONCLUSIONS: Targeted testing and treatment are important to the control of tuberculosis. The results of this study highlight the need for an aggressive physician educational campaign to identify latent tuberculosis infection and to tailor service delivery to meet the unique needs of foreign-born communities.     

PPD试验筛检大学新生肺结核结果分析

目的了解新生入学时肺结核感染状况,为制定预防控制措施提供依据。方法对河池学院2003-2006年新生共7282人进行PPD试验,阳性者进行胸透,胸透异常者再做胸片及痰结核菌检查,对资料进行统计分析。结果受检学生PPD试验阳性率为17.06%,强阳性率为3.89%,肺结核检出率为1.24‰。PPD试验阳性率农村高于城镇,分别为18.51%和14.31%,差异有统计学意义(p<0.05);男性高于女性,分别为18.95%和15.73%,差异有统计学意义(p<0.01)。结论PPD试验是在高校新生中发现肺结核的必要辅助诊断方法,根据试验结果对学生采取不同的预防措施,可有效地控制肺结核在高校的传播和流行。     

2021年重庆市新生筛查结核病结果分析

目的 分析重庆市不同医疗机构开展新生结核病筛查效果的异同,为学校结核病新生筛查工作提供参考。方法 通过《重庆市新生结核病筛查调查表》和《重庆市统计年鉴》收集2021年重庆市秋季入学的各教育阶段新生结核病筛查资料和学生人口数据,分析学生活动性肺结核患者检出率及结核菌素纯蛋白衍生物(purified protein derivative tuberculin, PPD)强阳性率,采用SPSS 25.0进行描述性分析和χ²检验。结果 2021年重庆市新生结核病筛查798 135人,筛查率为42.36%,其中高中(61.48%)、初中(54.93%)筛查率较高。共发现151人活动性肺结核患者,高中(34.82/10万)、高等教育(28.59/10万)及寄宿制初中(11.83/10万)检出率较高。学前教育及小学新生197 469人,主要由其他医疗机构(41.44%)开展筛查工作。非寄宿制初中新生有14 587人开展了结核症状筛查,以其他医疗机构筛查为主。寄宿制初中新生有194 457人开展了PPD筛查,不同类型医疗机构患者检出率差异有统计学意义(P=0.002),不同类型医...     

Mycobacterium tuberculosis transmission in a newborn nursery and maternity ward--New York City, 2003

Evaluating young children recently exposed to airborne Mycobacterium tuberculosis is a public health priority. If infected, children aged <2 years are at high risk for severe tuberculosis (TB) disease (e.g., TB meningitis). In December 2003, infectious pulmonary TB disease was diagnosed in a foreign-born nurse working in the newborn nursery and maternity ward of a New York City hospital (hospital A); the nurse had declined treatment for latent TB infection (LTBI) after testing positive 11 years earlier. An investigation including medical evaluation of contacts in the nursery and maternity ward was conducted by the Bureau of TB Control (BTBC) at the New York City Department of Health and Mental Hygiene, hospital A, and CDC. This report summarizes the results of that investigation, which determined that approximately 1,500 patients had been exposed to the nurse but the majority could not be located for evaluation. Among those who were tested, four infants had positive tuberculin skin test (TST) results, likely attributable to recent transmission of M. tuberculosis. The findings emphasize the difficulty of conducting contact investigations in certain settings and the importance of effective LTBI testing and treatment programs for health-care workers (HCWs) to prevent TB disease and subsequent health-care--associated transmission.     

Dual skin testing for latent tuberculosis infection: a decision analysis

BACKGROUND: Recent data indicate that 10- to 14-mm Mycobacterium tuberculosis purified protein derivative (PPD) reactions are often due to prior infections with nontuberculous mycobacteria. Therefore, use of a 10-mm cutpoint to define latent tuberculosis infection (LTBI) results in false-positive diagnoses and unnecessary treatment for LTBI. A second skin test, Mycobacterium avium sensitin (MAS), has been shown to accurately identify false-positive PPD results. OBJECTIVE: To compare the costs and accuracy of a single skin-test strategy (SST) with PPD alone with a dual skin-test strategy (DST) where 10- to 14-mm PPD results are also tested with MAS. METHODS: A decision analytic model was developed to evaluate the two strategies. The model accounted for the costs of skin testing, the costs of LTBI treatment, the costs of undetected LTBI, and the sensitivity and specificity of each strategy. RESULTS: We estimated that DST saved US dollars 3 per subject tested compared to SST. Savings were due to a reduction in false-positive PPD results and consequent reduction in unnecessary treatment for LTBI of >60%. The DST strategy was associated with a minimal increase in undetected LTBI (6% vs 7%). Results were stable for a broad range of parameter values. CONCLUSIONS: DST is a promising approach to improving the specificity of LTBI testing when a 10-mm PPD cutpoint is used and would reduce costs and unnecessary drug treatment.     

Trends in compliance with the guidelines for preventing the transmission of Mycobacterium tuberculosis among New Jersey hospitals, 1989 to 1996.

OBJECTIVE: To determine trends in compliance with the guidelines for preventing the transmission of Mycobacterium tuberculosis in healthcare facilities among New Jersey hospitals from 1989 through 1996. DESIGN: A voluntary questionnaire was sent to all 96 New Jersey hospitals in 1992. The 53 that responded were resurveyed in 1996. RESULTS: Of the 96 hospitals surveyed in 1992, 53 (55%) returned a completed questionnaire; 33 (64%) were community, nonteaching hospitals. In 1991, patients with tuberculosis (TB) were admitted at 38 (72%) of 53 hospitals, and from 1989 through 1991, patients with multidrug-resistant (MDR) TB were admitted at 15 (29%) of 52 hospitals. Twenty-nine (57%) of 51 reported having rooms meeting the Centers for Disease Control and Prevention (CDC) criteria for acid-fast bacilli (AFB) isolation. A nonfitted surgical mask was used as a respiratory protective device by healthcare workers (HCWs) at 28 (55%) of 51 hospitals. Attending physicians were included in tuberculin skin-testing (TST) programs at 5 (11%) of 45 hospitals. In the 1996 resurvey, 48 (94%) of 53 surveyed hospitals returned a completed questionnaire; 34 (81%) of 42 had TB patient admissions, and 4 (9%) of 43 had MDR TB patient admissions in 1996. Forty-five (96%) of 47 reported having rooms that met CDC criteria for AFB isolation. N95 respiratory devices were used by HCWs at 45 (94%) of 48 hospitals. Attending physicians were included in the TST programs at 22 (54%) of 41 hospitals. CONCLUSION: New Jersey hospitals have made improvements in availability of AFB isolation rooms, use of proper respiratory protective devices, and expansion of TST programs for HCWs from 1989 through 1996.     

传染病医院医务人员结核感染状况

目的了解传染病医院医务人员结核(TB)感染现况,探讨其感染TB的危险性及影响因素。方法对某传染病医院的全体医务工作者进行问卷调查和TB菌素纯蛋白衍化物（PPD）试验检测。结果该传染病医院全体职工TB感染发病率为48.18%。不同科室医务工作者的TB感染情况差异无统计学意义（P＞0.05）,不同工作年限、不同年龄、不同职称的医务工作者TB感染情况差异均有统计学意义（均P＜0.05）。文化程度、职称、目前居住情况、在结核感染门诊或病区的工作时间是TB感染的危险因素,其OR(95%CI)分别为1.70（1.03～2.80）、1.95（1.10～3.45）、1.84（1.03～3.28）、2.38（1.40～4.04）;个人防护是TB感染的保护因素［OR及OR95%CI为0.92（0.85～0.99）］。结论传染病医院的医务工作者是TB感染的高危人群,应加强自我防护意识,及早采取防护措施。     

Tuberculosis screening and compliance with return for skin test reading among active drug users.

OBJECTIVES: This study assessed the independent and combined effects of different levels of monetary incentives and a theory-based educational intervention on return for tuberculosis (TB) skin test reading in a sample of active injection drug and crack cocaine users. Prevalence of TB infection in this sample was also determined. METHODS: Active or recent drug users (n = 1004), recruited via street outreach techniques, were skin tested for TB. They were randomly assigned to 1 of 2 levels of monetary incentive ($5 and $10) provided at return for skin test reading, alone or in combination with a brief motivational education session. RESULTS: More than 90% of those who received $10 returned for skin test reading, in comparison with 85% of those who received $5 and 33% of those who received no monetary incentive. The education session had no impact on return for skin test reading. The prevalence of a positive tuberculin test was 18.3%. CONCLUSIONS: Monetary incentives dramatically increase the return rate for TB skin test reading among drug users who are at high risk of TB infection.     

Risk of tuberculous infection among healthcare workers in a tertiary-care hospital in Ankara, Turkey.

OBJECTIVE: To determine risk factors for tuberculin skin test (TST) positivity among healthcare workers (HCWs). DESIGN: Two-step TST was performed in 2002. SETTING: Tertiary-care hospital in Ankara, Turkey. PARTICIPANTS: A sample of 491 hospital HCWs were included. Information related to demographics, profession, work duration, department, and individual and family history of tuberculosis (TB) was obtained by a structured questionnaire. RESULTS: Four hundred eight (83%) had two-step TST positivity. On multivariate analysis, male physicians (relative risk [RR], 1.5; 95% confidence interval [CI95], 1.23-1.69; P = .001), nurses (RR, 1.5; CI95, 1.29-1.66; P = .005), radiology technicians (RR, 1.7; CI95, 1.35-1.73; P = .002), laboratory technicians (RR, 1.6; CI95, 1.3-1.74; P = .007), and male housekeepers (RR, 1.6; (HCWs). CI95, 1.38-1.7; P < .001) had a higher risk than did female physicians. Among laboratory technicians, radiology technicians had the highest TST positivity (85%). HCWs working for less than 1 year (RR, 0.8; CI95, 0.72-0.98; P = .027) had a lower risk of infection. The HCWs having bacille Calmette-Guerin vaccination (RR, 1.12; CI95, 1.08-1.45) had higher TST positivity. CONCLUSION: Male physicians, nurses, and laboratory technicians had increased risk of Mycobacterium tuberculosis infection in this setting, but community exposure likely accounted for most infections.