Bone mineral density and bone scintigraphy in adult Saudi female patients with osteomalacia

OBJECTIVE: This prospective study was conducted to demonstrate the role of bone mineral density (BMD) and bone scan in the management of adult Saudi female patients with established diagnosis of osteomalacia.

METHODS: Bone scan using Tc99m methylene diphosphonate (MDP) and BMD of the lumbar spine and femoral neck using dual x-ray absorptiometry (DXA) were performed at the time of diagnosis 6 months and one year after therapy in 96 Saudi female patients attending the metabolic bone disease clinic at King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia, between January 1997 through to June 1999, aged between 20 and 73-years (mean 42 years). Alkaline phosphatase, calcium and inorganic phosphorus were measured for all patients before and after treatment. 25 Hydroxy Vitamin D was only measured with the first BMD measurements.

RESULTS: The bone profile showed typical biochemical abnormalities of osteomalacia. The bone scan showed feature of "superscan" in all patients and "pseudofractures" in 43 patients. Bone mineral density measurements were compared with that of normal Saudi subjects matched for age and sex. The BMD was significantly low at diagnosis and showed significant improvement after therapy. The improvement of bone density in response to therapy was more evident in lumbar spine than in femoral neck bone.

CONCLUSION: Our results showed that BMD in adult Saudi female patients with osteomalacia was markedly affected probably due to specific constitutional and environmental factors (inadequate exercise, lack of sun exposure and lack of intake of milk and dairy products). In addition, lumbar BMD and serum calcium appeared to be better markers to monitor therapy. Bone scan helped in demonstrating disease activity, the presence of pseudofractures.