急性粟粒性肺结核的CT及病理对照研究

CT and pathologic correlation of acute miliary pulmonary tuberculosis

目的探讨急性粟粒性肺结核（AMPT）的CT表现特征及病理基础。方法回顾性分析25例AMPT的CT表现，并对人类免疫缺陷病毒（HIV）阳性和阴性组各种CT征象的发生率行双侧确切概率法X^2检验。HIV阴性组2例尸检全肺标本行冠状面HRCT扫描，并切割成10mm厚度肺标本薄片，选取结节丰富区制作冠状面大切片（80～150μm）和5μm组织切片，将CT与病理所见进行对照观察；对其中1例HRCT和病理显示微结节在肺小叶的分布行X^2检验。结果25例AMPT患者中HIV阳性11例，阴性14例。HRCT扫描发现所有AMPT患者两肺均随机分布着弥漫微结节，磨玻璃密度（GGO，17例）是主要的伴发征象。结节融合、肺实变仅出现在HIV阳性患者中（分别为5和6例），阴性患者无一例。分析2例尸检病例，结节以小叶中心与小叶周边之间肺组织分布最多（分别为792和560个），病理证实位于肺泡间隔；其中1例HRCT显示结节在肺小叶内的分布（1060个微结节）与病理所见（864个结节）差异无统计学意义（X^2=2．814，P〉0．05）。AMPT合并急性呼吸窘迫综合征（ARDS）于HRCT上表现为弥漫GGO，病理基础为肺水肿、炎症及肺泡透明膜。结论AMPT的CT表现有一定特征，呈血行分布结节；肺内出现弥漫GGO需警惕合并ARDS。

Objective To elucidate the CT characteristics and pathology of acute miliary pulmonary tuberculosis （AMPT）. Methods The CT features of AMFF in 25 cases were analyzed retrospectively, and the CT features in HIV-seronegative and HIV-seropositive patients were compared by 2-sided exact propability Chi-square test. Two lung specimens were inflated and fixed by Heitzman＇s method. HRCT scans, gross specimen section （80-150 p.m） and histologic section （5 μm） were performed on dry lung specimens and CT-pathologic correlation was conducted. The distribution of micronodules in the secondary lobule on HRCT and pathology in one specimen was evaluated by Chi-square test. Results Twenty five patients with AMPT were included in this study, including 11 HIV-seropositive patients and 14 HIVseronegative patients. HRCT showed diffuse micronodules randomly distributed throughout both lungs in 25 patients, and ground-glass opacity （ 17 patients）was the predominant complicated finding. Coalescence of nodules and consolidation in HIV-seropositive patients （5 and 6 patients） were markedly higher than that in HIV-seronegative patients （none）. In lung specimens, most nodules located in the lung parenchyma between the central bronchovascular bundle and the perilohular structures （792 and 560 nodules） , which located in the interlobular septum pathologically. The distribution of micronodules in the secondary lobule showed on HRCT （ 1060 nodules） and pathology （ 864 nodules ） was not significantly difference （ X^2 = 2. 814, P 〉 0.05 ）. HRCT showed ground-glass opacities when ARDS occured, which were pulmonary edema, inflammation and hyaline membrane on alveolar wall pathologically. Conclusions The HRCT characteristic of nodule distribution in AMPT is random. ARDS should be suspected when diffuse ground-glass opacities appear on HRCT.