Effect of intravenous pamidronate treatment in children with osteogenesis imperfecta

ABSTRACT

To assess the beneficial effect of intravenous pamidronate treatment in children with osteogenesis imperfecta [OI]. Experimental study. Endocrine Unit at the National Institute of Child Health, Karachi, Pakistan, from January 2007 to December 2011. All children diagnosed with osteogenesis imperfecta on the basis of repeated spontaneous fractures and typical radiological findings registered during the study period, were included in this study. Pamidronate therapy were offered to those with more than 3 fractures per year or had platyspondyly. Pamidronate disodium was diluted in isotonic saline and administered by slow ravenous infusion over 3 hours in a dosage 1 mg/kg/day for 3 consecutive days 3 monthly for 2 years. Fracture rate, bone mineral density [BMD], mobility score, wellbeing and pain episodes were evaluated at baseline and 2 years after the treatment. Good response was defined as less than 2 fractures per year or mobility score improvement and poor response as more than 2 fracture per year with mobility score less than 2. Seventy two patients were included in this study. There were 40 boys and 32 girls with mean age of 3.64 +/- 3.2 years. The annual fracture rate decreased overall from 5.8 +/- 1.61 to 0.6 +/- 0.93 [p < 0.001]. BMD Z-score improved from -5.3 +/- 1.74 to -1.7 +/- 0.72 [p < 0.001]. Mobility score was 0.94 +/- 1.30 at baseline and 2.5 +/- 1.02 at the end of the treatment [p < 0.001]. Wellbeing gained from 3.63 +/- 1.44 to 7.8 +/- 1.18 [p < 0.001] and pain episode improved from 24.1 +/- 8.15 to 2.7 +/- 8.31 [p < 0.001]. Good response was noted in 92% of patients and poor response in 8% patients. Bisphosphonate seems to be an effective symptomatic treatment for children with osteogenesis imperfecta irrespective of severity of mutation or clinical phenotype. Cyclical bisphosphonate therapy has a positive effect on fracture rate, BMD, mobility score, wellbeing and pain episode