Osaki M, Adachi H, Gomyo Y, Yoshida H, Ito H
First Department of Pathology, Faculty of Medicine, Tottori University, Japan.
Mod Pathol. 1997 Jan;10(1):78-83.
Granuloma is a chronic inflammatory process associated with noninfectious agents or infectious diseases such as tuberculosis. Determination of the causative agent might be occasionally difficult in histopathologic sections. In this study, we examined 60 specimens of granuloma or inflammatory lesions that were originally diagnosed as 51 cases of granulomatous inflammation, 6 of leprosy, and 3 of atypical mycobacteriosis. The diagnoses in the last two categories were made both histologically and clinically. All of the sections and DNA were prepared from formalin-fixed, paraffin-embedded blocks. Histopathologic and immunohistochemical findings were compared with the results of duplex polymerase chain reaction (PCR) using two primers to amplify mycobacterial-common 383-base pair (bp) DNA and Mycobacterium tuberculosis-complex-specific 240-bp DNA. Six samples of leprosy and three of atypical mycobacteriosis showed the 383-bp but not the 240-bp band. Among the 51 specimens of granulomatous inflammations, nine showed no band of even the beta-globin, the cases being excluded from this analysis. The 42 specimens of granulomatous inflammation were subdivided into three categories by PCR: (1) 383- and 240-bp positive; (2) 383-bp positive and 240-bp negative; and (3) both negative. Category 1 included 32 specimens (76.2%), being considered as tuberculosis. One specimen was classified into Category 2, indicating possible atypical mycobacterium. Category 3 included nine specimens, composed of five of sarcoidosis and four other agent-induced granulomas, when compared with histologic and clinical findings. These findings indicate that the PCR assay using DNA extracted from paraffin-embedded materials provides useful information to differentiate tuberculosis from other type of granulomas.
肉芽肿是一种与非感染性因子或诸如结核病等感染性疾病相关的慢性炎症过程。在组织病理学切片中，偶尔可能难以确定病原体。在本研究中，我们检查了60份肉芽肿或炎性病变标本，这些标本最初被诊断为51例肉芽肿性炎症、6例麻风病和3例非典型分枝杆菌病。后两类疾病的诊断是通过组织学和临床检查做出的。所有切片和DNA均从福尔马林固定、石蜡包埋的组织块中制备。将组织病理学和免疫组化结果与使用两种引物进行双链聚合酶链反应（PCR）的结果进行比较，这两种引物用于扩增分枝杆菌通用的383碱基对（bp）DNA和结核分枝杆菌复合群特异性的240-bp DNA。6份麻风病样本和3份非典型分枝杆菌病样本显示出383-bp条带，但未显示240-bp条带。在51份肉芽肿性炎症标本中，9份甚至连β-珠蛋白条带都未显示，这些病例被排除在本分析之外。通过PCR将42份肉芽肿性炎症标本分为三类：（1）383-和240-bp阳性；（2）383-bp阳性而240-bp阴性；（3）两者均为阴性。第1类包括32份标本（76.2%），被认为是结核病。1份标本被归类为第2类，表明可能是非典型分枝杆菌。与组织学和临床结果相比，第3类包括9份标本，其中5份为结节病，4份为其他因子诱导的肉芽肿。这些结果表明，使用从石蜡包埋材料中提取的DNA进行PCR检测可为区分结核病与其他类型的肉芽肿提供有用信息。
