Intravenous pamidronate treatment in Filipino children with moderate to severe osteogenesis imperfecta

ABSTRACT

Objective. To present preliminary data on the effects of intravenous pamidronate in children with moderate to severe Osteogenesis Imperfecta (OI). Methods. This is a restrospective study wherein a review of medical records and available serial radiographs of children (N=14) with moderate to severe IO started on pamidronate from 2006 to 2010 was done. Results. Two children have IO Type I, 8 have IO Type III and 4 have IO Type IV. At baseline, 2 had normal height, 8 had height less than minus 2SD and the rest with less than minus 1SD. Twelve out of 14 had vertebral compression fractures. Mean age at start of pamidronate was 5.4 years (range 0.5-11 years). First infusion fever in five patients and transient generalized macular rash in one child were noted. Serum calcium and phosphorus levels were normal at baseline and remained stable. Based on parental report, improvement of motor function was noted. In the 10 children who had at least a year of treatment, long bone fractures decreased from mean annualized fracture rate of 2.6 at baseline to 0.9. In patients with vertebral compression fractures, serial radiographs showed improvement of vertebral shape. Conclusion. This preliminary study shows that treatment was generally well tolerated and led to decrease in long bone fractures, improved vertebral shape and improved function.