Acquired resistance to pamidronate treated effectively with zoledronate in juvenile Paget ’s disease

AbstractJuvenile Paget ’s disease (JPD) is a rare autosomal recessive osteopathy. There is still a question about the most effective treatment modality in long-term prognosis. A 9-month-old boy who suffered from bone pain and deformities with a very high alkaline phosphatase level was diagnosed as JPD by radiographic fi ndings. Genetic analysis showed a homozygous large deletion inTNFRSF11B gene encoding osteoprotegerin. Clinical improvement was observed with intravenous pamidronate therapy. However, the effect of drug reduced in time so the annual dose per kilogram body weight was increased after 2  years. Despite this increment, bone fractures developed and bone pain recurred with high-ALP levels, which suggested resistance to pamidronate. Switching to zoledronate resulted a significant improvement in bone findings radiographically and ALP level. Severe hypocalcemia requiring intravenous cal cium treatment complicated the first dose of zoledronate, but not recurred thereafter. Intravenous pamidronate therapy is effective in reducing bone pain, improving bone deformities and motor development in infantile onset JPD. However, this effect can be transient. Switching to another bisphosphona te like zoledronate may provide long-term clinical and biochemical improvement as an alternative treatment in case of resistance to pamidronate therapy.
Source: Osteoporosis International - Category: Orthopaedics Source Type: research