Clinical analysis of 36 cases of IgG4-related disease

Abstract

Objective To explore the clinical characteristics of IgG4-related disease (IgG4-RD) in Chinese by detailed clinicopathological and laboratory assessments. Methods The baseline features of 36 patients with biopsy-proven disease were reviewed. The diagnosis was confirmed by pathology review according to consensus diagnostic criteria and clinicopathologic correlation. Disease activity and damage were assessed by the IgG4-RD responder index (RI). Results Thirty (83.3%) of the patients were male, while six were female, and the average age of onset was 65.1 years. All of the 36 patients had active disease, in which submandibular gland, lymph nodes, retroperitoneal tissue were the most common affected organs in this group of patients. Among 36 patients, 77.7% had elevated serum IgG4 concentrations and 44.4% had hypocomplementemia. Patients with elevated serum IgG4 had a higher RI, a greater number of organs involved (P<0.01 for all comparisons). The correlation between serum IgG4 level and RI (r=0.737, P<0.01) was stronger than IgG, ESR, CRP and serum complement levels. The incidence of hypocomplementemia in IgG4-RD patients with renal involvement was higher than that in IgG4-RD patients with other organs involvement (P<0.01). Twenty-eight patients received glucocorticoids therapy, and had lower RI and serum IgG4 concentration after therapy (P<0.05). Conclusions Both IgG4-RD RI and IgG4 concentration may be regarded as assessment markers of disease activity and therapeutic effect of IgG4-RD. The diagnosis of IgG4-RD should be supported by histopathology and clinical features. Key words: Immunoglobulin G; Diagnosis; Therapy; IgG4 related disease; Clinical feature