Immunosuppressive therapy for acute porphyria: safety and efficacy in a patient with bone marrow failure

Acute intermittent porphyria is a rare disorder of heme biosynthesis with a clinical course characterized by exacerbations of neurologic symptoms. Drugs may precipitate these exacerbations; however, little is known about the safety of most drugs used to treat the disease. We describe a patient with acute intermittent porphyria who developed bone marrow failure and was successfully treated with cyclosporine. This agent has been reported as being unsafe for patients with acute intermittent porphyria based on an in vitro model. However, cyclosporine was used in this patient based on two published case reports of successful cyclosporine therapy in patients with acute intermittent porphyria undergoing kidney transplantation. Our patient tolerated cyclosporine well, and her blood counts demonstrated improvement. To our knowledge, this is the first case report of cyclosporine used for treatment of bone marrow failure in a patient with acute intermittent porphyria. Until more data are available, clinicians should consider immunosuppressive therapy as a safe option for treating certain patients with acute intermittent porphyria.