Division of Nephrology, Kaohsiung Veterans General Hospital, 386 Ta-Chung 1st Rd., Kaohsiung, 813, Taiwan.
National Yang-Ming University, School of Medicine, Taipei, Taiwan.
Osteoporos Int. 2019 Feb;30(2):519-523. doi: 10.1007/s00198-018-4679-2. Epub 2018 Aug 31.
Denosumab, a novel agent that inhibits osteoclasts, reduces the risk of fracture in patients with osteoporosis. However, worsening of hypophosphatemia and other symptoms may be induced by denosumab in patients with pre-existing hypophosphatemic osteomalacia. A 58-year-old man with hepatitis B presented with diffuse bone pain and muscle weakness. Denosumab was prescribed by the orthopedist according to documented low bone mass and spine compression fracture. After administering denosumab, the patient's bone pain worsened, and he later developed a right tibia stress fracture. His condition was diagnosed as adult-onset hypophosphatemic osteomalacia complicated by multiple bone fractures, which resulted from Fanconi syndrome with proximal tubulopathy due to tenofovir disoproxil fumarate (TDF) treatment for his hepatitis B. Denosumab use leads to aggressive hypophosphatemic osteomalacia and the complication of stress fractures, because of its effects on bone resorption. Physicians should be aware that in patients with chronic hepatitis B monoinfection who are administered TDF therapy, bone pain or fracture is possible but preventable by timely monitoring of serum phosphate levels. Denosumab should not be used in patients with untreated osteomalacia or vitamin D deficiency, as it may lead not only to hypocalcemia but also to hypophosphatemia in these patients.
地舒单抗是一种新型的骨吸收抑制剂，可降低骨质疏松症患者骨折的风险。然而，地舒单抗可能会使患有先前存在的低磷性骨软化症的患者出现低磷血症恶化和其他症状。一位 58 岁的男性乙型肝炎患者出现全身骨痛和肌肉无力。骨科医生根据明确的低骨量和脊柱压缩性骨折开具了地舒单抗。地舒单抗给药后，患者的骨痛加重，后来出现右胫骨应力性骨折。他的病情被诊断为成人发病的低磷性骨软化症合并多发性骨折，这是由于乙型肝炎用富马酸替诺福韦二吡呋酯（TDF）治疗引起的范可尼综合征伴近端肾小管病变所致。地舒单抗的使用会导致严重的低磷性骨软化症和应力性骨折的并发症，因为它会影响骨吸收。医生应该意识到，在接受 TDF 治疗的慢性乙型肝炎单感染患者中，可能会出现骨痛或骨折，但通过及时监测血清磷酸盐水平可以预防。地舒单抗不应在未经治疗的骨软化症或维生素 D 缺乏症患者中使用，因为它不仅可能导致低钙血症，还可能导致这些患者出现低磷血症。
