Tocilizumab in the treatment of IgG4-related disease involving the carotid artery-case report and literature review

IgG4-related disease (IgG4-RD) is an autoimmune disorder characterized by fibroinflammatory infiltration of affected organs. This systemic condition can involve multiple organs, including the pancreas, bile ducts, salivary glands, kidneys and lungs. However, IgG4-related disease demonstrates substantial heterogeneity and frequently involves atypical anatomical sites, leading to frequent clinical misdiagnosis. We report a rare case of IgG4-RD involving the carotid artery and vagus nerve, presenting with hoarseness and syncope. Diagnosis was confirmed via contrast-enhanced neck MRI and carotid artery biopsy. The patient exhibited poor response to glucocorticoids and methotrexate but achieved sustained remission following combination therapy with tocilizumab. A literature review revealed that isolated involvement of the carotid artery and vagus nerve in IgG4-RD is exceptionally rare.