Johnson H, Lee B, Doherty E, Kelly E, McDonnell T
Eastern Health Board, Community Care, Dublin, Ireland.
Tuber Lung Dis. 1995 Apr;76(2):122-5. doi: 10.1016/0962-8479(95)90553-7.
Tuberculosis clinic, St Vincents Hospital, Dublin.
To determine the influence of past BCG vaccination on tuberculin sensitivity in tuberculosis contacts.
Prospective cohort study of tuberculin sensitivity using the Mantoux technique (5 TU).
In 1050 contacts of 96 cases of tuberculosis, BCG scars were noted in 76% of the contacts. Approximately 50%, 30% and 20% of the contacts respectively had negative (0-4 mm), positive (5-14 mm) and strongly positive (15+ mm) Mantoux responses. The presence of a BCG scar was not found to significantly influence the degree of tuberculin sensitivity. The degree of tuberculin sensitivity increased after 20 years and decreased after 60 years of age. Contacts of sputum-positive cases of tuberculosis had larger Mantoux responses.
The study suggests that age of the contact and sputum status of the index case are important determinants of the degree of tuberculin sensitivity. Attributing a 'positive' Mantoux response to past BCG vaccination may be encouraging a false sense of security in contacts recently exposed to an infectious case of tuberculosis. Contact management guidelines may need to be reviewed and perhaps modified to reflect this finding.
都柏林圣文森特医院结核病诊所。
确定既往卡介苗接种对结核病接触者结核菌素敏感性的影响。
采用曼托试验技术（5 TU）对结核菌素敏感性进行前瞻性队列研究。
在96例结核病患者的1050名接触者中，76%的接触者有卡介苗接种疤痕。分别约50%、30%和20%的接触者曼托试验反应为阴性（0 - 4毫米）、阳性（5 - 14毫米）和强阳性（15毫米及以上）。未发现卡介苗接种疤痕的存在对结核菌素敏感性程度有显著影响。结核菌素敏感性程度在20岁后升高，60岁后降低。痰涂片阳性结核病患者的接触者曼托试验反应更大。
该研究表明，接触者的年龄和索引病例的痰涂片状况是结核菌素敏感性程度的重要决定因素。将曼托试验“阳性”反应归因于既往卡介苗接种可能会使近期接触结核病传染源的接触者产生错误的安全感。可能需要审查并修改接触者管理指南以反映这一发现。
