Endocrine Abstracts

Introduction: Osteogenesis imperfecta (OI) is a congenital, generalized connective tissue disorder characterized by severe osteoporosis and bone fragility. OI is most commonly caused by mutations in genes encoding the α-1 and α-2 chains of type I collagen or proteins involved in posttranslational modification of type I collagen. Although, no controlled studies are done, bisphosphonates are used for the treatment of OI. I.v. bisphosphonates are reported to be more effective for pain conrol than oral bisphosphonates. Here, we report the results of a patient with OI and osteoporosis who received cyclic i.v. pamidronate.

Case report: A 31 years old man with OI and osteoporosis admitted with generalized bone pain. He had been using alendronate 70 mg/week p.o. for 2 years with no improvement in bone mineral density (BMD) and pain. I.v. cyclic pamidronate was started at a dose of 60 mg/day for 3 days every 4 months. BMD was assessed at baseline, at 6 and 12 months of treatment. Short form-36 (SF-36) questionnaire was used to evaluate his quality of life at baseline and at 12 months. His vertabral BMD T-score was −4.2 and femur neck T-score was −2.0 at baseline. At 6th month, his vertabral BMD T-score was −3.6 and femur neck T-score was −1.6. At 12th month, his vertabral BMD T-score was −3.6 and femur neck T-score was −1.4. A significant improvement was observed in his SF-36 scores at 12th month. No adverse effects were observed due to treatment.

Conclusions: OI is a rare disease and no treatment protocol has been shown to be superior to others. I.v. bisphosphonates may be better for pain control than oral bisphosphonates. This case shows the improvement of BMD and quality of life after 1 year treatment with i.v. pamidronate, which not achived with oral alendronate.