Coronary Artery Aneurysms Presenting as Acute Coronary Syndrome: An Unusual Case of IgG4-Related Disease Vascular Involvement.

We report the case of a 65-year-old man referred to our department because of a complex coronary aneurysmal disease presenting as subacute ST-segment elevation myocardial infarction due to intraluminal thromboembolism. The patient's past medical history (recurrent episodes of lymphadenopathies, parotid swelling, prostatitis, and dacryoadenitis) raised the suspicion of a unifying systemic disorder with coronary involvement. An extensive infectious and autoimmune screening was performed, leading to the final diagnosis of IgG4-related disease. Our case highlights the importance to include this rare and recently described disease in the diagnostic workup of acquired coronary aneurysms.