Multimodal Therapy for Vertebral Involvement of Systemic Mastocytosis

Abstract

Case report and clinical discussion. To describe a rare case of vertebral involvement of systemic mastocytosis and its multimodal therapy. Vertebral fractures in young men are rare events. A thorough diagnostic work-up that unravels the underlying cause of osteoporosis and appropriate therapy are crucial to prevent further fractures. A 36-year-old man was evaluated for severe back pain and was found to suffer from progressive osteoporosis and multiple vertebral fractures. Bone biopsy analysis revealed tryptase-positive mast cells that were positive for c-KIT, thus confirming the diagnosis of systemic mastocytosis. In addition to zoledronic acid (4 mg per month) and prednisolone (50 mg per day) treatment, the patient underwent kyphoplasty. The procedure was associated with arterial hypotension which was most likely because of pressure-induced mast cell degranulation. Follow-up visits demonstrated stable bone mineral density and tolerable back pain while on zoledronic acid. Systemic mastocytosis is a rare cause of vertebral fractures in young men. Because of the potential risk of pressure-induced release of the allergy mediator histamine, kyphoplasty for vertebral involvement of systemic mastocytosis should be conducted with appropriate precautions.