Mastocytose als oorzaak van osteoporotische fracturen: casusbespreking en literatuurstudie

Abstract

Mastocytosis as a cause of osteoporotic fractures: a case report and literature review Systemic mastocytosis is a rare cause of secondary osteoporosis. Mastocytosis is a myeloproliferatic disease characterized by abnormal growth and proliferation of mast cells. The disease is associated with activating KIT mutations. There are 2 major types of mastocytosis: cutaneous mastocytosis and systemic mastocytosis with extracutaneous infiltration. Systemic mastocytosis needs to be considered in the differential diagnosis of unexplained osteoporosis, unexplained spinal fractures (especially in men and premenopausal women) and in patients with osteoporosis with severe bone pain. Bone involvement is one of the most frequent expressions of systemic mastocytosis, especially in adults. The clinical presentation is diverse: from osteoporosis with fragility fractures and poorly localized bone pain to asymptomatic osteolytic and/or focal sclerotic lesions and diffuse osteosclerosis. Osteoporosis in patients with systemic mastocytosis is caused by neoplastic infiltration or, more likely, local release of mediators. Screening for mastocytosis is possible by determining the serum basal tryptase and searching for a p.D816V KIT mutation, but the final diagnosis requires a bone marrow examination. The first-line treatment of osteoporosis secondary to mastocytosis consists of bisphosphonates and denosumab. Teriparatide can be considered in patients with new vertebral fractures under treatment with antiresorptive therapy, but more research is needed to evaluate its effectivity and safety. In case of refractory osteoporosis caused by mastocytosis, cytoreductive therapy, whether or not in combination with bisphosphonates, can be administered. In this article, the authors report a case of a 48-year-old patient with osteoporosis as the first manifestation of underlying mastocytosis. A literature review was performed to describe the etiology, pathophysiology, diagnostic process and treatment options of bone involvement in patients with mastocytosis.