AIM:To discuss clinical pathological features of orbit IgG4 related disease(IgG₄-RD).

METHODS: The clinical pathological materials of 23 patients(35 eyes)with orbit IgG₄-RD were collected. They were observed in terms of histology and immunohistochemistry, and its clinical and pathologic characteristics were summarized.

RESULTS: There were 23 patients(35 eyes)with orbit IgG₄-RD(8 male patients, 9 eyes; 15 female patients, 26 eyes), with an average age of 52.1 year-old(from age 28 to 72). 19 patients(30 eyes)occured in lacrimal gland and 4 cases(5 eyes)in other places, and they went to hospital for lacrimal gland cyst or exophthalmos. There were 11 cases in one side and 12 cases in both sides. The disease lasted from 1mo to 10a, averaging 27mo. It recureded in one patient(1 eye)after 1mo. In general inspection: Gray nodular goiter, thin fibrous coat wrapping around the lacrimal gland could be observed. Histologic characteristics: lacrimal gland bubble and catheter group shrinked or even disappeared, substituted by lymphocyte, plasma cells and lymphoid follicle and accompanied with fibrosis. Immunohistochemical staining: IgG₄ positive plasma cells of 23 cases(35 eyes)was >50/HPF, and IgG₄/IgG ratio of positive plasma cells was >40%.

CONCLUSION: Orbit IgG₄-RD mainly occures in lacrimal gland tissue, and expression of IgG₄ can be detected through histologic characteristics and immunohistochemical staining. IgG₄-RD should be screened, prevented and treated in the early phase.