Temporal arteritis caused by eosinophilic vasculitis associated with a lymphocytic variant of the hypereosinophilic syndrome: A case report

Temporal arteritis in patients under the age of 50 years is an unusual form of vasculitis with a group of aetiologies that include rheumatological and hematological diseases. Additionally, vasculitis mimickers should be excluded. We describe a case of temporal arteritis due to eosinophilic vasculitis in a 36-year-old woman, associated with a lymphocytic-variant of hypereosinophilic syndrome. She presented facial and neck swelling, pruritic hive-like lesions, subtle thickening in the left temporal artery, headache, visual alterations, mandibular claudication, and hypereosinophilia. The temporal artery biopsy confirmed panmural eosinophilic vasculitis, and peripheral blood and bone marrow flow cytometry revealed T lymphocytes with aberrant immunophenotype (CD3⁻CD4⁺). This case report describes the clinical features, histology, and treatment of temporal arteritis in young patients and hypereosinophilic syndrome, as well as clues for their differential diagnosis.