Intravenous pamidronate treatment improves growth in prepubertal osteogenesis imperfecta patients.

Background/aims: Pamidronate is widely used to treat pediatric patients with osteogenesis imperfecta (OI). We aimed at delineating the effects of monthly pamidronate therapy on the growth of different body segments in prepubertal OI patients.

Methods: The study included 14 prepubertal patients (12 boys, 2 girls) with mild forms of OI (type I and IV). The mean age at treatment start was 7:8 years:months (3:7-11:0). Pamidronate was given as monthly intravenous infusions. The patients were measured 1 year before, at treatment start and 1 and 2 years after treatment start.

Results: Height standard deviation score (SDS) and sitting height SDS significantly increased (p < 0.05) during the first year of treatment when compared to the pre-treatment year. No further improvement was detected during the second year of treatment. However, when plotted on disease-specific growth charts (untreated patients with the same OI types), height gain was significant during the first (p < 0.001) and second (p < 0.05) years of treatment. All patients increased their bone mineral density throughout the follow-up.

Conclusion: Monthly pamidronate improves the growth of prepubertal patients with mild OI, where the most prominent growth stimulation is seen in the upper body segment.