The Management of Adynamic Bone Disease with Teriparatide

Presentation Number: SAT 320
Date of Presentation: April 1st, 2017

Swathi Sista* and Seth Mathew Arum
University of Massachusetts, Worcester, MA

Abstract

Background:Teriparatide (PTH 1-34) is a PTH analog that is FDA approved to treat post-menopausal osteoporosis. The use of teriparatide in managing adynamic bone disease, which is a multi-factorial process characterized by low-bone turnover, PTH resistance, and relative PTH deficiency may prove promising in improving bone-related outcomes.

Clinical Case: A 67 year-old woman with a history of long-standing, severe osteoporosis in the setting of CKD stage 5 from lupus nephritis presented to the Endocrinology Clinic due to multiple compression fractures. She was initially treated by her Rheumatologist with alendronate and low-dose calcitriol soon after her first fracture, though given her underlying history of renal dysfunction her dose of alendronate was briefly reduced by 50%. Due to ongoing fractures, her alendronate was eventually increased to the full dose and she was referred to Endocrinology for further evaluation. At her first clinic visit, she was noted to have relatively low intact parathyroid hormone (iPTH) (46 pg/mL, n 12-65 pg/mL) and bone-specific alkaline phosphatase (BSAP) (8.0 mcg/L, n 5.6-29.0), thus raising concerns for adynamic bone disease (ABD). She was advised to discontinue both alendronate and calcitriol and to undergo repeat iPTH (85 pg/mL) and BSAP (15.9 mcg/L) in 4 weeks. Seeing that both studies remained relatively unchanged, a bone biopsy was performed revealing low-bone turnover, thus confirming a diagnosis of ABD. Soon after her diagnosis, she began treatment with teriparatide and has yet to sustain another compression fracture as confirmed on plain films of the thoracic and lumbar spine nearly 18 months since initiating this therapy. Furthermore, her iPTH subsequently increased (119 pg/mL) and her BSAP remains stable (10.8 mcg/L). An English-language literature search reveals 4 individual studies describing 17 patients with biopsy-proven ABD who were treated with teriparatide. They achieved similar increases to their iPTH soon after initiating treatment, and had improvements to their bone mineral density as measured on dual-energy x-ray absorptiometry (DXA).

Conclusion: This case demonstrates the potential benefit of using teriparatide as a treatment strategy in patients with adynamic bone disease so as to improve their bone-related outcomes.

 

Nothing to Disclose: SS, SMA