Alavi Seyed Mohammad, Sefidgaran Gholam Hossein
Jondishapoor Infectious and Tropical Diseases Research Center, Jondishapoor University of Medical Sciences, Ahvaz, Khuzestan, Iran.
Int J Infect Dis. 2008 Jul;12(4):406-9. doi: 10.1016/j.ijid.2007.11.005. Epub 2008 Jan 11.
The tuberculin test is widely used for the diagnosis of tuberculosis (TB) in children, as it is the only one to provide evidence of infection with Mycobacterium tuberculosis. Our objective was to estimate the prevalence of TB infection, the annual risk of infection (ARI), and the incidence of active TB in school children.
A cross-sectional study was carried out in Ahvaz, a city of southern Iran, in 2006. A questionnaire was used to collect information, including demographic characteristics, bacillus Calmette-Guérin (BCG) vaccination history, and household contact with active TB. Tuberculin testing was performed. Reactivity that measured < 5 mm was considered negative, between 5 and 9 mm was considered doubtful, and > or = 10mm was considered positive. Chest radiographs were obtained as part of the evaluation for children with a positive result.
A total of 3906 children with a mean+/-standard deviation (SD) age of 10.59+/-2.63 years (51% female, 49% male) were entered into our study. Of these, 3338 children (85.5%) did not develop a reaction (0mm), 243 (6.2%) had reactivity of 1-4mm, 238 (6.1%) had reactivity of 5-9 mm, and 87 (2.2%) had reactivity of > or = 10 mm. More than 90% of the children had received the BCG vaccine in the first week of life. The ARI rate was 0.5% and the estimated case of smear-positive TB was approximately 25 per 100000 population. Only three children were diagnosed with active TB, a prevalence of 75 per 100000 population.
Tuberculin testing using 5TU-PPD (5 tuberculin units of purified protein derivative) is a valuable diagnostic test for latent TB and active TB in childhood. BCG vaccination has no remarkable effect on the interpretation of tuberculin reactivity. The incidence rate of active pulmonary TB in children in the region of study is of concern.
结核菌素试验广泛用于儿童结核病（TB）的诊断，因为它是唯一能提供结核分枝杆菌感染证据的检测方法。我们的目的是估计学龄儿童结核感染率、年感染风险（ARI）和活动性结核病发病率。
2006年在伊朗南部城市阿瓦士开展了一项横断面研究。采用问卷调查收集信息，包括人口统计学特征、卡介苗（BCG）接种史以及与活动性结核病患者的家庭接触情况。进行结核菌素检测。测量结果<5mm为阴性，5至9mm为可疑，≥10mm为阳性。对检测结果呈阳性的儿童进行胸部X光检查作为评估的一部分。
共有3906名儿童纳入我们的研究，其平均年龄为10.59±2.63岁（女性占51%，男性占49%）。其中，3338名儿童（85.5%）无反应（0mm），243名（6.2%）反应为1 - 4mm，238名（6.1%）反应为5 - 9mm，87名（2.2%）反应≥10mm。超过90%的儿童在出生第一周接种了卡介苗。ARI率为0.5%，估计涂片阳性结核病病例约为每10万人口25例。仅3名儿童被诊断为活动性结核病，患病率为每10万人口75例。
使用5TU - PPD（5结核菌素单位的纯化蛋白衍生物）进行结核菌素检测是诊断儿童潜伏性结核和活动性结核的重要检测方法。卡介苗接种对结核菌素反应性的判读无显著影响。研究地区儿童活动性肺结核的发病率令人担忧。
