Giant cell arteritis and microangiopathic hemolytic anemia

Area of Science:

• Rheumatology
• Hematology
• Pathology

Background:

• Giant cell arteritis (GCA) is a systemic vasculitis primarily affecting medium and large arteries.
• Microangiopathic hemolytic anemia (MAHA) is characterized by red blood cell fragmentation due to intravascular fibrin deposition.
• The association between GCA and MAHA is rare, with limited reported cases.

Observation:

• A 67-year-old woman with biopsy-proven giant cell arteritis presented with microangiopathic hemolytic anemia.
• The patient experienced recurrent episodes of hemolytic anemia.
• Symptoms and the hemolytic process showed significant improvement with high-dose steroid therapy.

Findings:

• The patient's MAHA was directly linked to her underlying giant cell arteritis.
• Erythrocyte fragmentation in MAHA is attributed to contact with intravascular fibrin, a mechanism potentially exacerbated by GCA-related vasculitis.
• This case represents the first documented instance of MAHA occurring in conjunction with temporal arteritis (a common form of GCA).

Implications:

• This case highlights a potential, albeit rare, hematological complication of giant cell arteritis.
• It underscores the importance of considering MAHA in GCA patients presenting with anemia and fragmented red blood cells.
• Effective management of the underlying vasculitis with immunosuppression may resolve the associated MAHA.