ESPE Abstracts

Background: Paediatric Osteoporosis can be a devastating complication of Duchenne muscular dystrophy (DMD). Treatment with intravenous bisphosphonates such as pamidronate is currently the first treatment choice for paediatric osteoporosis of different etiologies.

Objective and hypotheses: The aims of our study were i) to identify the proportion of boys with DMD with osteoporosis in our service and ii) to evaluate the side-effect profile of those treated with zoledronic acid. Zoledronic acid was selected in our DMD cohort in preference to pamidronate due to the shorter administration and thus reduced time spent in hospital.

Method: All boys under 16 years with a diagnosis of DMD seen in a tertiary referral centre were included in this cohort. Patient characteristics were collected both from hospital records and via direct patient contacts. Patients treated with bisphosphonates were interviewed following their first infusion of zoledronic acid to establish the tolerability and side-effect profile of treatment.

Results: Of 61 patients (mean age 10.0 years, range 1 to 16 years) with DMD, 62% had been treated with corticosteroids. 11% had a diagnosis of osteoporosis and were commenced on zoledronic acid. Patients treated with zoledronic acid were older compared to non-treated patients (Mean±S.D., 13.6±5.4 vs 10.1±4.3 P<0.05) and more likely to be treated with steroids (100 vs 42% P<0.01).

All DMD boys with osteoporosis were in wheelchairs and had on average been treated for 8 years on corticosteroids. 43% of them had pubertal delay. Side effects after first infusion included pyrexia (29%), vomiting (14%), aches and pain (42%). Increased energy levels were noted in 14% patients. All patients reported that the side effects were mild and tolerated well.

Conclusion: 11% of paediatric DMD patients were diagnosed with osteoporosis and started on treatment with zoledronic acid. This was well tolerated with only minor short-term side effects being reported.