Department of Radiology, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea.
Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
PLoS One. 2020 Apr 17;15(4):e0231537. doi: 10.1371/journal.pone.0231537. eCollection 2020.
To investigate the prevalence, patient characteristics, and natural history of clustered micronodules (CMs) in active pulmonary tuberculosis.
From January 2013 through July 2018, 833 consecutive patients with bacteriologically or polymerase chain reaction-proven active pulmonary tuberculosis were retrospectively evaluated. CMs were defined as a localized aggregation of multiple dense discrete micronodules, which primarily distributed around small airways distal to the level of the segmental bronchus: small airways surrounded by CMs maintained luminal patency and the CMs might coalesce into a larger nodule. The patients were dichotomized according to whether the predominant computed tomography (CT) abnormalities were CMs. We analyzed radiologic and pathologic findings in patients whose predominant diagnostic CT abnormalities were CMs, along with those of incidental pre-diagnostic CT scans, if available. Chi-square, McNemar, Student t-test and Wilcoxon-signed rank test were performed.
CMs were the predominant CT abnormality in 2.6% of the patients (22/833, 95% CI, 1.8-4.0%) with less sputum smear-positivity (4.8% vs 31.0%; p = .010) and a similar proportion of immunocompromised status (40.9% vs 46.0%; p = .637) than those without having CMs as the predominant CT abnormality. The time interval for minimal radiologic progression was 6.4 months. The extent of CMs increased with disease progression, frequently accompanied by consolidation and small airway wall thickening. Pathologically, smaller CMs were non-caseating granulomas confined to the peribronchiolar interstitium, whereas larger CMs were caseating granulomas involving lung parenchyma. Two of the five patients with a pre-diagnostic CT scan obtained more than 50 months pre-diagnosis showed an incipient stage of CMs, in which they were small peribronchiolar nodules.
Active pulmonary tuberculosis manifested predominantly as CMs in 2.6% of patients, with scarce of acid-fast bacilli smear-positivity and no association with impaired host immunity. CMs indolently progressed, accompanied by consolidation and small airway wall thickening, and originated from small nodules.
研究活动性肺结核中簇状微结节（CMs）的患病率、患者特征和自然史。
回顾性评估了 2013 年 1 月至 2018 年 7 月期间 833 例经细菌学或聚合酶链反应证实的活动性肺结核患者。CMs 定义为多个密集离散微结节的局部聚集，主要分布在段支气管以下的小气道周围：CMs 包围的小气道保持管腔通畅，CMs 可能融合成更大的结节。根据主要 CT 异常是否为 CMs 将患者分为两组。我们分析了主要诊断性 CT 异常为 CMs 的患者的影像学和病理学发现，并在有条件的情况下分析了偶发性诊断前 CT 扫描的结果。采用卡方检验、McNemar 检验、Student t 检验和 Wilcoxon 符号秩检验。
CMs 是 2.6%（22/833，95%CI，1.8-4.0%）患者的主要 CT 异常，痰涂片阳性率较低（4.8%比 31.0%；p=0.010），免疫抑制状态比例相似（40.9%比 46.0%；p=0.637）。与主要 CT 异常无 CMs 的患者相比，CMs 患者的影像学进展时间间隔为 6.4 个月。CMs 的范围随着疾病的进展而增加，常伴有实变和小气道壁增厚。病理学上，较小的 CMs 是局限于细支气管周围间质的非干酪样肉芽肿，而较大的 CMs 是累及肺实质的干酪样肉芽肿。5 例在诊断前 50 个月以上获得 CT 扫描的患者中有 2 例表现为 CMs 的早期阶段，表现为细支气管旁小结节。
活动性肺结核患者中有 2.6%主要表现为 CMs，痰抗酸杆菌涂片阳性率低，与宿主免疫受损无关。CMs 缓慢进展，伴有实变和小气道壁增厚，由小结节起源。
