Temporal Periarteritis in Immunoglobulin G4-Related Disease.

Immunoglobulin G4 (IgG4)-related arteritis/periarteritis commonly involves the aorta, carotid arteries, and coronary arteries but rarely involves the temporal artery. Here, we report a case of IgG4-related periarteritis involving the temporal artery. A 79-year-old man presented with fever, bilateral leg pain, and bilateral jaw claudication. Physical examination revealed the absence of the right temporal artery pulse. Ultrasonography of the right temporal artery showed vessel wall thickening, and biopsy revealed marked infiltration of IgG4-positive plasma cells in the adventitia. Serum IgG4 levels were also elevated, confirming the diagnosis of IgG4-related periarteritis of the temporal artery. His symptoms rapidly improved following the initiation of prednisolone. This case demonstrates that IgG4-related arteritis/periarteritis can affect the temporal artery. Moreover, in patients with fever of unknown origin, evaluation of jaw claudication and palpation of the temporal arteries is essential, even in the absence of headache.