Fig. 1

The initial lesion site and organ involvement of patients with IgG4-ROD and nIgG4-ROD. a The constituent ratio of initial lesion site in IgG4-ROD and nIgG4-ROD patients. The three most frequent initial lesions in IgG4-ROD patients were the ocular (41.6%), salivary gland (34.9%), and pancreas (9.0%), while in nIgG4-ROD patients were the pancreas (32.9%), salivary gland (23.4%), and retroperitoneal fibrosis (16.8%). b Comparison of organ involvement except for ocular between patients with IgG4-ROD and nIgG4-ROD. The percentages of patients with the salivary gland, paranasal sinus, lung, and lymph node involvement in IgG4-ROD group were higher than those in nIgG4-ROD group, while nIgG4-ROD patients had higher percentages of retroperitoneal fibrosis and biliary system lesions. *P < 0.05, **P < 0.01