Clinical Case:

A 34 year old Chinese woman presents to hospital with sudden left sided chest pain after coughing.  CXR confirms the presence of a rib fracture.  Her past medical history is significant for SLE nephritis (current eGFR 18) and chronic prednisone use.  Other medications include cholecalciferol 1.25mg monthly and calcium carbonate 1.25g per day.

Investigations confirm the presence of low bone density on DXA scan with right neck of femur T score -2.6; left neck of femur T score -1.8 and lumbar spine -2.4.  Blood tests reveal a serum PTH of 17.8pmol/L; adjusted serum calcium of 2.26mmol/L; serum phosphate of 1.79mmol/L and P1NP 39.3ug/L (pre-menopausal women normal range 15-60ug/L).  Screens for other secondary causes of osteoporosis are negative.  She is referred to the Endocrine clinic for advice. 

Discussion

Osteoporosis in the setting of chronic renal failure presents a diagnostic and management challenge.  Whilst chronic renal failure is an established risk factor for the development of osteoporosis, it is also associated with osteodystrophies, including osteitis fibrosa, osteomalacia and adynamic bone disease.  In clinical practice, it may be difficult to rule out adynamic bone disease without bone biopsy, and this has important implications for management.¹  Bisphosphonates are the mainstay of treatment for osteoporosis, however safety and efficacy in the setting of chronic renal failure is unclear^.2-3  Other treatments such as teriparatide may also be contraindicated in this setting.  In this publication, the evidence surrounding the appropriate diagnosis and management of osteoporosis in the setting of renal failure is explored.