Bouvet E, Casalino E, Mendoza-Sassi G, Lariven S, Vallée E, Pernet M, Gottot S, Vachon F
Clinique de Réanimation des Maladies Infectieuses, Faculté Xavier Bichat, Paris, France.
AIDS. 1993 Nov;7(11):1453-60. doi: 10.1097/00002030-199311000-00008.
To identify risk factors in a nosocomial outbreak of multidrug-resistant Mycobacterium bovis (MDRMB) tuberculosis (TB) among HIV-infected patients.
We evaluated the study period (from the first to the last MDRMB smear-positive patients hospitalized in the unit) using a case-control study with three control groups. Since MDRMB is extremely rare, we assumed that a single strain was responsible for all six cases.
A 19-bed infectious diseases unit in Paris, France.
The index case was an AIDS patient who was hospitalized in September 1989 because of MDRMB TB. The cases were five HIV-infected patients who developed MDRMB TB between January 1990 and October 1991. Controls were randomly selected from HIV-infected patients in our unit during the study period (case-control study 1, 15 patients), during the contact period (at least one MDRMB smear-positive patient hospitalized in the unit; case-control study 2,20 patients), and patients matched according to the length of contact (case-control study 3, 24 patients).
After detecting the nosocomial outbreak, we took respiratory isolation precautions for all patients suspected of having active TB.
Risk factors for MDRMB nosocomial transmission, and the occurrence of new cases of MDRMB infection in HIV-infected patients and health-care workers after the introduction of isolation precautions.
The most important predictor of nosocomial transmission of MDRMB to HIV-infected patients was the (mean +/- s.d.) length of contact in days [cases, 22 +/- 15.8; study 1 controls, 11.2 +/- 18.9 (P = 0.07); study 2 controls, 14.6 +/- 8.5 (P = 0.043)]. Only one case of MDRMB TB resulted from exposure to MDRMB-smear-positive patient after the introduction of respiratory isolation measures. The incubation period in the single health-care worker who developed MDRMB TB was longer than in the cases.
In a nosocomial outbreak of MDRMB TB, the contact time was the main risk factor of transmission to HIV-infected patients. Respiratory isolation measures appear to be effective.
确定在感染人类免疫缺陷病毒（HIV）的患者中发生耐多药牛分枝杆菌（MDRMB）结核病医院感染暴发的危险因素。
我们采用包含三个对照组的病例对照研究方法对研究期间（从该科室收治的首例至最后一例MDRMB涂片阳性患者）进行了评估。由于MDRMB极为罕见，我们假定单一菌株导致了所有6例感染。
法国巴黎一家拥有19张床位的传染病科室。
首例病例是一名艾滋病患者，于1989年9月因MDRMB结核病住院。病例组为1990年1月至1991年10月期间发生MDRMB结核病的5例HIV感染患者。对照组分别为：在研究期间从本单位HIV感染患者中随机选取的患者（病例对照研究1，15例）、在接触期（该科室至少有1例MDRMB涂片阳性患者住院期间；病例对照研究2，20例）以及根据接触时长匹配的患者（病例对照研究3，24例）。
在发现医院感染暴发后，我们对所有疑似患有活动性结核病的患者采取了呼吸道隔离预防措施。
MDRMB医院感染传播的危险因素，以及采取隔离预防措施后HIV感染患者和医护人员中MDRMB感染新病例的发生情况。
MDRMB向HIV感染患者发生医院感染传播的最重要预测因素是以天为单位的（均值±标准差）接触时长[病例组，22±15.8；研究1对照组，11.2±18.9（P = 0.07）；研究2对照组，14.6±8.5（P = 0.043）]。在采取呼吸道隔离措施后，仅有1例MDRMB结核病是由于接触MDRMB涂片阳性患者所致。发生MDRMB结核病的唯一一名医护人员的潜伏期比病例组更长。
在MDRMB结核病医院感染暴发中，接触时间是向HIV感染患者传播的主要危险因素。呼吸道隔离措施似乎有效。
