IgG4相关非特异性间质性肺炎四例临床病理分析

The clinicopathological analysis of 4 cases of IgG4-related nonspecific interstitial pneumonia

目的观察非特异性问质性肺炎（NSIP）病变组织中IgG4的表达情况，探讨IgG4相关非特异性问质性肺炎的临床病理特点。方法回顾性分析2002年11月至2010年10月北京协和医院具有完整临床资料的32例NSIP患者，均经开胸肺活检。所有标本经4％中性甲醛固定，石蜡包埋和免疫组织化学染色，从中筛选出符合IgG4相关性疾病病理诊断的病例共4例，并对其临床病理资料进行回顾性分析，包括一般资料、实验室检查和病理组织学检查等。结果4例患者中男1例、女3例，年龄44～56岁；患者主要因干咳、气短就诊；1例自身免疫性抗体阳性，无类风湿因子（RF）阳性病例。病理组织学检查示4例病变均呈弥漫性分布，保留肺组织结构；肺间质内可见较多浆细胞、淋巴细胞浸润，肺泡间隔内有不同程度的纤维组织增生，肺间质内可见嗜酸粒细胞浸润〉5个／高倍视野，2例可见含有生发中心的淋巴滤泡形成，1例出现阻塞性动脉炎。4例IgG4阳性浆细胞数目均数分别为42、22、11和33个／高倍视野，IgG4与IgG阳性浆细胞数目比值（IgG4／IgG）分别为70％、71％、57％和43％。结论少许NSIP样病理组织学改变为IgG4相关性间质性肺疾病，IgG4相关NSIP在病理形态上主要表现为间质内较多淋巴细胞、浆细胞及散在嗜酸粒细胞浸润，伴间质内不同程度纤维化，淋巴细胞聚集伴有淋巴滤泡形成，偶见阻塞性动脉炎。I譬G及IgG4免疫组织化学染色有助于其病理诊断。

Objectives To observe the immunohistochemical staining of IgCA in nonspecific interstitial pneumonia （NSIP） and to study the clinicopathological features of IgCA-related NSIP. Methods Retrospective analysis was carried out for 32 patients with NSIP who had been admitted into Peking Union Medical College Hospital from November 2002 to October 2010. The diagnosis of NSIP was established by surgical lung biopsy and all specimens were fixed in neutral formalin and embedded in paraffin. Sections were cut for HE and immunohistochemical stain. According to the diagnostic criteria for IgG4-related disease, 4 cases were confirmed to be IgG4-related NSIP. The clinicopathological features including clinical history, laboratory examination, and pathologic evaluation were studied. Results The 4 patients with IgG4-related NSIP included 1 man and 3 women, with a median age of 48 years （range, 44 -56 years）. The presenting symptoms were dry cough or shortness of breath. One patient （ 1/4,25.0% ） was found to have a positive autoantibody but no cases showed positive RF in serum. The histological finding of the 4 cases was characterized by inflammatory cell infiltration in interstitium with fibrosis, and 1 case showed obliterative arteritis. The numbers of IgG4-positive plasma cells in the 4 cases were 42/hpf, 22/hpf, ll/hpf, and 33/hpf respectively, while the percentages of IgG4-positive to IgG-positive plasma cells were 70% , 71% , 57% ,43% respectively. Conclusions IgG4-related interstitial pulmonary disease can be characterized as the NSIP pattern. The pathological features of IgG4-related NSIP include infiltration of lymphoplasmacytes and eosinophils in interstitium with fibrosis, and lymphoid follicles are frequently identified in the area of lymphocyte aggregation, but obliterative arteritis is infrequently identified in the lesion. Immunohistochemical staining of IgG and IgG4 is very helpful for a definite diagnosis of IgG4-related disease.