Department of Pathology, University of British Columbia, Canada.
Am J Surg Pathol. 2012 May;36(5):774-8. doi: 10.1097/PAS.0b013e318248713d.
Pulmonary hyalinizing granulomas (PHGs) are unusual fibrosclerotic inflammatory lung lesions. The organ-based manifestations of the recently defined IgG4-related sclerosing disease typically show dense fibrosis and heavy lymphoplasmacytic infiltrates. IgG4-related sclerosing disease is also defined by increased serum IgG4 levels and increased tissue levels of IgG4-positive plasma cells. The morphologic features of PHG overlap with those seen in IgG4-related sclerosing disease, and this suggests that PHG may be a form of IgG4-related sclerosing disease. We present a case of a 51-year-old man with a history of sarcoidosis who presented with slowly enlarging pulmonary nodules. Histologic evaluation of one of the nodules yielded a diagnosis of PHG. Further investigation demonstrated both elevated serum IgG4 and elevated tissue IgG4-positive plasma cells in the PHG. In previous reports, lesions that are now considered part of IgG4-related sclerosing disease were documented in patients also diagnosed with PHG, although these reports date from before the description of IgG4 sclerosing disease. This case provides the first definitive evidence that PHG is part of the spectrum of IgG4-related sclerosing disease.
肺透明变性肉芽肿（PHG）是一种不常见的纤维硬化性炎症性肺部病变。最近定义的 IgG4 相关硬化性疾病的器官表现通常表现为致密纤维化和大量淋巴浆细胞浸润。IgG4 相关硬化性疾病还定义为血清 IgG4 水平升高和组织中 IgG4 阳性浆细胞水平升高。PHG 的形态学特征与 IgG4 相关硬化性疾病所见重叠，这表明 PHG 可能是 IgG4 相关硬化性疾病的一种形式。我们报告了一例 51 岁男性，有结节病病史，表现为逐渐增大的肺部结节。其中一个结节的组织学评估诊断为 PHG。进一步研究显示 PHG 中血清 IgG4 和组织 IgG4 阳性浆细胞均升高。在以前的报告中，现在被认为是 IgG4 相关硬化性疾病一部分的病变也在被诊断为 PHG 的患者中得到证实，尽管这些报告是在 IgG4 硬化性疾病描述之前。该病例首次明确证实 PHG 是 IgG4 相关硬化性疾病谱的一部分。
