Cyclic pamidronate therapy in children with osteogenesis imperfecta: results of treatment and follow-up after discontinuation.
BACKGROUND
Cyclic intravenous pamidronate treatment is widely used for symptomatic therapy of osteogenesis imperfecta (OI). However, data after discontinuation are very limited.


OBJECTIVE
The results of cyclical pamidronate treatment in 14 patients with moderate/severe OI and follow up of six of them after discontinuation are presented to assess the effects of pamidronate and its discontinuation.


METHODS
Pamidronate was administered at a dosage of 0.5 mg/kg for 3 successive days every 2 months in 14 patients with OI aged 5.10 +/- 3.68 years. Treatment was stopped in six patients after a duration of 16.33 +/- 4.63 months, due to stable bone mineral density (BMD) values and/or no fracture in the last 6 months, or due to family demand. The main outcome measures were areal BMD (aBMD) of the lumbar spine, biochemical markers of bone metabolism, fracture rate, and clinical evaluation.


RESULTS
Areal BMD and aBMD z-scores showed significant improvement during the treatment period. Both serum and bone-specific alkaline phosphatase values were significantly decreased. Fracture rate reduced significantly from 3.5 +/- 1.01 to 0.83 +/- 0.77 fractures/year. Bone pain, which was severe in five patients, disappeared just after the first cycle, and the activity and mobility of patients increased. aBMD and aBMD z-scores were decreased 1.5 years after discontinuation, although not statistically significant. Annual fracture rate increased significantly. Bone pain recurred in four patients. Pamidronate treatment was reinstituted in five of these patients at the end of 1.5 years.


CONCLUSIONS
Cyclical pamidronate treatment is very effective in children with moderate/severe OI. This treatment should be started early enough before the occurrence of irreversible deformities and must be given for a longer time during the growth period.
Andiran
Nesibe
N
Division of Endocrinology, Department of Pediatrics, Faculty of Medicine, Hacettepe University, Ankara, Turkey. nesandiran@yahoo.com
Alikasifoglu
Ayfer
A
Gonc
Nazhl
N
Ozon
Alev
A
Kandemir
Nurgun
N
Yordam
Nursen
N
D000293:Adolescent; D000469:Alkaline Phosphatase / Q000097:blood; D015519:Bone Density / Q000187:drug effects / Q000502:physiology; D050071:Bone Density Conservation Agents / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology; D002648:Child; D002675:Child, Preschool; D004164:Diphosphonates / Q000008:administration & dosage* / Q000009:adverse effects / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D050723:Fractures, Bone / Q000517:prevention & control; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D010013:Osteogenesis Imperfecta / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D017063:Outcome Assessment, Health Care; D000077268:Pamidronate; D011859:Radiography; D013131:Spine / Q000000981:diagnostic imaging; D016896:Treatment Outcome
D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D000469:Alkaline Phosphatase; D000077268:Pamidronate