IgG4相关性肺疾病26例临床病理分析OA

Objective To improve the understanding of the clinicopathological features of IgG4-related lung dis-ease(IgG4-RLD)and to reduce misdiagnosis and missed diagnosis.Methods Clinicopathological data from 26 pa-tients diagnosed with IgG4-RLD were collected.Morphological and immunohistochemical features were retrospectively analyzed,and relevant literature was reviewed.Results Among the 26 patients,24 were male and 2 were female,with a median age at onset of 62 years.Histologically,all cases showed varying degrees of lymphoplasmacytic infiltra-tion(26/26)and interstitial fibrosis.Obliterative vasculitis was observed in a minority of cases(6/26).Immunopheno-typically,more than 40 IgG4-positive plasma cells per high-power field(HPF)were identified in hotspot areas,and the IgG4/IgG ratio exceeded 40%.Serum IgG4 levels were elevated in 14 cases,within the normal range in 8 cases,and not examined in 4 cases.Conclusion IgG4-RLD is pathologically characterized mainly by lymphoplasmacytic in-filtration and variable degrees of fibrosis,whereas obliterative vasculitis is relatively uncommon.Clinically,the dis-ease predominantly affects middle-aged and elderly men.Serum IgG4 levels have limited diagnostic value and show no significant correlation with patient sex,age,clinical symptoms,lesion consistency,or maximum lesion diameter.