Low-dose intravenous pamidronate treatment in osteogenesis imperfecta

Different therapy models have been tried in order to decrease bone resorption in osteogenesis imperfecta. Bisphosphonates are a group of drugs that mainly suppress osteoclast-mediated bone resorption, thus reducing bone turnover. We assessed the effects of low-dose bisphosphonate treatment in children with osteogenesis imperfecta. Sixteen osteogenesis imperfecta patients (12 female, 4 male) with severe deformities were treated with cyclic (3-4 mg/kg/year) intravenous infusions of bisphosphonate (Aredia-Novartis) therapy for a period ranging from 0.6 to 4.7 years (mean 2.50 +/- 1.09 years). Bone mineral density increased from 0.304 +/- 0.146 g/cm2 to 0.362 +/- 0.142 g/cm2 in the first year and to 0.421 +/- 0.146 g/cm2 in the second year. A clinical response was shown with a reduction in fracture rate and improvement in mobilization scores. Fracture rates decreased from a median of 4/year (0-30/year) before treatment to 0/year (0-5/year) during treatment. Ambulation improved in 10 children and remained unchanged in three. Two of the children were fully functional before therapy and one was below two years of age. No adverse effects were seen with pamidronate infusions of 7-10 mg/kg/year (monthly) or with 4 cycles/year 3-4 mg/kg/year. Low-dose cyclical pamidronate infusions markedly increased bone density and decreased bone fracture rate and should be considered as a part of a multi-disciplinary treatment.     

Bone densitometry in pediatric patients treated with pamidronate

Background: Increasing numbers of children are being treated with the bisphosphonate pamidronate for low bone mineral density, particularly children with increased risk of fractures caused by bone disorders or low/non-weight bearing. Objective: To determine the effect of intravenous pamidronate on the bone mineral density of children with osteogenesis imperfecta and spastic quadriplegic cerebral palsy. Materials and methods: Charts of 38 children with osteogenesis imperfecta (n=20) and spastic quadriplegic cerebral palsy (n=18) treated with pamidronate were retrospectively reviewed. Patients were selected for treatment because of prior fracture and/or abnormally low bone mineral density. All received intravenous pamidronate at two-month to eight-month intervals and were periodically examined using dual energy X-ray absorptiometry. Results: All patients had abnormally low bone mineral density prior to treatment. Lumbar spine bone mineral density and z-scores showed serial improvement in 31 of 32 patients. Spine bone mineral density increased 78±38.1% in OI and 47.4±39.0% in children with cerebral palsy. The area of greatest lateral distal femur bone mineral density improvement was in the metaphysis adjacent to the growth plate, with a 96±87.8% improvement in the osteogenesis imperfecta group and 65.7±55.2% improvement in the cerebral palsy group. Increases in bone mineral density exceeded that expected for age-specific growth. This was demonstrated by improvement in both spine and femur z-scores for both groups. No children with spastic quadriplegic cerebral palsy experienced fractures after the first week of treatment, whereas patients with osteogenesis imperfecta continued to have fractures but at a decreased rate. Conclusions: Intravenous pamidronate given at 3- to 4-month intervals proved to be effective in increasing bone mineral density in patients with osteogenesis imperfecta and spastic quadriplegic cerebral palsy. The greatest gains in bone mineral density were observed in the children with osteogenesis imperfecta, but they did continue to fracture, albeit at a decreased rate. Children with cerebral palsy gained bone mineral density and did not continue to fracture.     

A comparison of oral and intravenous bisphosphonate therapy for children with osteogenesis imperfecta

Bone mineral density and fracture rates in children with osteogenesis imperfecta improve with intravenous bisphosphonates. The efficacy of oral bisphosphonates has not been established. This report is an analysis of an open-label, prospective, randomized clinical trial of oral compared to intravenous bisphosphonate medications in children with osteogenesis imperfecta. Children were stratified according to bone age, pubertal stage, and type of osteogenesis imperfecta and then randomized to receive intravenous pamidronate, 3 mg/kg over 3 days every 4 months, or oral alendronate 1 mg/kg, from a minimum of 10 mg to a maximum of 20 mg daily. The primary efficacy outcome was change in bone mineral density. Secondary outcomes included change in biomarkers of bone turnover, fracture incidence, and growth rate. Ten children were randomized (6 oral and 4 intravenous). Two other children were assigned to intravenous treatment due to chronic abdominal pain. In each group, three patients had type III/IV osteogenesis imperfecta, while three had type I. All 12 children completed 8 months of therapy; nine completed 12 months. Bone mineral density increased in both oral and intravenous groups equally and beyond that expected with normal growth. All children had a decrease in biochemical markers of bone turnover. Linear growth showed a moderate increase above that for age. There was a non-significant decrease in fracture incidence in both groups.     

Osteogenesis imperfecta: anthropometric, skeletal and mineral metabolic effects of long-term intravenous pamidronate therapy

BACKGROUND: Administration of bisphosphonates represents a beneficial therapy in children and adolescents with severe osteogenesis imperfecta (OI) because it significantly reduces the annual rate of bone fractures. AIM: To evaluate the anthropometric, skeletal and mineral metabolic effects of long-term intravenous pamidronate therapy in OI. METHODS: Ten patients, aged 5 mo to 25 y, with OI received cyclical intravenous pamidronate. The yearly dose of pamidronate was approximately 9 mg/kg/d at all ages. Duration of treatment varied from a minimum of 2 y to a maximum of 5 y. Growth, bone mass and mineral metabolic parameters were studied at baseline and repeated every year thereafter. Bone mass was assessed by calculation of bone mineral apparent density (L2-L4 BMAD). This represents the first study on the changes in size-adjusted measures of bone mass observed with such therapy. RESULTS: While on therapy, all children and adolescents grew normally but did not experience any manifest catch-up growth. A significant decrease in the incidence of bone fractures was observed. In seven patients with severe forms, L2-L4 BMAD increased by 80% after the first 2 y of therapy but tended to stabilize or even decrease over the following years despite maintenance of therapy. A significant inverse correlation could be established between urinary Ca excretion and L2-L4 BMAD (r = -0.30, p < 0.05). CONCLUSION: Our results confirm that cyclical pamidronate infusions reduce the incidence of bone fractures and allow normal growth. The improvement in bone mass initially observed after the first 2 y of therapy is not always sustained over the following years despite maintenance of therapy.     

Intravenous pamidronate treatment of infants with severe osteogenesis imperfecta.

OBJECTIVE: Children with the severe forms of osteogenesis imperfecta have in several studies been treated with intravenous pamidronate, but there are only few reports of the effect of early treatment. AIM: To evaluate the effect of treatment started in infancy. METHODS: In a prospective observational study, with a historic control group, intravenous disodium pamidronate (APD) was given as monthly infusions to 11 children with osteogenesis imperfecta aged 3-13 (median 3.6) months, who had severe osteogenesis imperfecta with congenital bowing of the femora and vertebral compression fractures. RESULTS: During treatment of children aged between 3 and 6 (median 4.5) years, dual-energy x ray absorptiometry measurements of the lumbar spine showed a gradual increase in bone density. Bone metabolism parameters in serum (alkaline phosphatase, osteocalcin, procollagen 1 carboxy-terminal peptide, collagen 1 teleopeptide) and in urine (deoxypyridinoline) indicated a decrease in bone turnover. An improvement of mobility was seen and at the latest recording, at the age of 3.3-6.5 (median 4.8) years, the children could all walk. Vertebral remodelling was seen, with increased vertebral height, and no child developed scoliosis, kyphosis or basilar impression. All children required femoral intramedullar rods for fractures, and five needed tibial rodding for extreme curvatures that prevented functional standing and walking. No adverse effects were seen on growth, fracture healing or blood chemistry. CONCLUSIONS: APD is an efficient symptomatic treatment for infants with severe osteogenesis imperfecta, but additional orthopaedic surgery is often needed. Early treatment may prevent scoliosis and basilar impression. Long-term follow-up is important.     

Effect of intravenous pamidronate therapy on functional abilities and level of ambulation in children with osteogenesis imperfecta

OBJECTIVE: To evaluate the functional abilities and the level of ambulation during pamidronate therapy in children with moderate to severe osteogenesis imperfecta. STUDY DESIGN: Functional abilities, ambulation, and grip force were assessed in 59 patients (mean age, 6.1 years; range, 0.5-15.7 years; 30 girls) during 3 years of pamidronate treatment. Functional skills (mobility and self-care) were both assessed by using the Pediatric Evaluation of Disability Inventory. Ambulation level was assessed by using the modified Bleck score. For 48 patients, results after 3 years of pamidronate treatment could be matched to those of patients with similar age and disease severity who had not received pamidronate. RESULTS: Mobility and self-care scores increased during the study period (+43% and +30%, respectively). The average ambulation score changed from 0.8 to 1.9. Maximal isometric grip force increased by 63%. Mobility and ambulation scores and grip force measures were significantly higher than in patients who had not received pamidronate. The difference in self-care scores did not reach significance. CONCLUSION: This study suggests that cyclical pamidronate treatment improves mobility, ambulation level, and muscle force in children with moderate to severe osteogenesis imperfecta.     

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. AIM: 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. PATIENTS AND 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. CONCLUSION: 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.     

Hypercalcaemia in osteogenesis imperfecta treated with pamidronate

The response to the bisphosphonate, pamidronate, is reported in a child with osteogenesis imperfecta who had recurrent symptomatic hypercalcaemia after immobilisation following fractures. Oral clodronate was effective in the prevention of immobilisation hypercalcaemia in the same child. The bisphosphonates may have other roles in osteogenesis imperfecta by decreasing bone turnover.     

Hypercalcaemia in osteogenesis imperfecta treated with pamidronate

Accepted 10 September 1996The response to the bisphophosphonate, pamidronate, is reported in a child with osteogenesis imperfecta who had recurrent symptomatic hypercalcaemia after immobilisation following fractures. Oral clodronate was effective in the prevention of immobilisation hypercalcaemia in the same child. The bisphosphonates may have other roles in osteogenesis imperfecta by decreasing bone turnover.     

Beneficial effect of bisphosphonate during five years of treatment of severe osteogenesis imperfecta

We report results of 2-5 y treatment with intravenous disodium pamidronate (APD) in three girls with severe osteogenesis imperfecta (OI). Treatment was given as monthly infusions. Additional oral 1,25-dihydroxycholecalciferol was given to compensate for a transient decrease in serum calcium levels. During treatment, DEXA measurements showed a gradual increase in bone density in all patients. All parameters analysed in serum (ALP, osteocalcin, PICP, ICTP) and in urine (deoxypyridinoline and pyridinoline) showed a decreased bone turnover. The two younger patients reported a major improvement in well-being, pain and activities of daily life. The effect on the older patient was less pronounced. No negative side effects in clinical or laboratory variables were observed. This study indicates that APD is of value in the symptomatic treatment of children with severe OI.     

Pamidronate treatment of osteogenesis imperfecta--lack of correlation between clinical severity, age at onset of treatment, predicted collagen mutation and treatment response

Severe forms of osteogenesis imperfecta (OI) are characterised by osteoporosis with multiple fractures, deformity, progressive loss of mobility and chronic bone pain. Bisphosphonates, as osteoclast inhibitors, reduce bone turnover and improve osteoporosis. OBJECTIVE: To investigate the effect of pamidronate treatment of severe OI in children, and find any correlation between clinical severity, age at start of treatment, type of predicted collagen mutation and treatment response. DESIGN: Open, observational trial. PATIENTS: A two-year study of pamidronate treatment was undertaken in a cohort of 18 children, (1.4-14.5 years) with OI types III and IV. INTERVENTIONS: Disodium pamidronate, 1 mg/kg/day for 3 days every 4 months, by i.v. infusion with measurement of bone turnover, bone density, vertebral morphology and skin biopsies to assess collagen mutation. RESULTS: Eleven children have completed 2 years of treatment and three more have completed 20 months. Sustained cessation of bone pain, improved mobility and decreased fracture rate were seen in all patients. Bone turnover decreased slightly but was not statistically significant. Bone mineral density (BMD) of lumbar spine increased by a mean of 124.7 +/- 75.7% over 2 years (Z score mean -5.08 +/- 1.27, to -3.30 +/- 1.71, p <0.001); the greatest change in BMD was seen in the most severely affected patients: 138 +/- 50.6% (severe), 62.47 +/- 22.9% (mild). There was a mean increase in vertebral height at L4 of 68.5% and in vertebral area of 85.4%. The majority of patients had slow electrophoretic migration of type I collagen alpha chains or reduced secretion of type I collagen, indicative of structural, helix-breaking mutations. There was no correlation between phenotypic severity, age at start of treatment and treatment response (r2 = 0.14) CONCLUSIONS: Pamidronate treatment of severe forms of OI is an effective therapeutic modality to increase bone density, decrease fracture rate, increase mobility and improve quality of life, irrespective of the severity of the mutation or clinical phenotype. It has a good short-term safety profile.     

Beneficial effect of long term intravenous bisphosphonate treatment of osteogenesis imperfecta.

AIM: To find an effective symptomatic treatment for osteogenesis imperfecta (OI). METHODS: In a prospective observational study disodium pamidronate (APD) was given as monthly intravenous infusions to 28 children and adolescents (aged 0.6-18 years) with severe OI or a milder form of the disease, but with spinal compression fractures. RESULTS: During treatment for 2-9 years, dual energy x ray absorptiometry measurements of the total body and of the lumbar spine showed a gradual increase in bone density. All bone metabolism variables in serum (alkaline phosphatase, osteocalcin, procollagen 1 C-terminal peptide, collagen 1 teleopeptide) and urine (deoxypyridinoline) indicated that there was a decrease in bone turnover. All patients experienced beneficial effects and the younger patients reported a major improvement in wellbeing, pain, and mobility without significant side effects. Vertebral remodelling was also seen. CONCLUSIONS: APD seems to be an efficient symptomatic treatment for children and adolescents with OI.     

Effect of long-term calcitonin therapy by injection and nasal spray on the incidence of fractures in osteogenesis imperfecta.

The effect of calcitonin therapy by injection or nasal spray on the incidence of bone fractures was studied in patients with osteogenesis imperfecta. In contrast to injection of calcitonin, intranasal administration of calcitonin twice a week for 2 weeks, followed by 2 weeks of no therapy, was simple and seemed beneficial for decreasing bone fractures in patients with osteogenesis imperfecta.     

Efficacy of low dose schedule pamidronate infusion in children with osteogenesis imperfecta

BACKGROUND: Osteogenesis imperfecta (OI) is a rare condition in which bones are abnormally brittle with frequent fractures. A variety of therapeutic agents has been used with low efficacy. In this study, we present three patients treated for 4 years with i.v. pamidronate. PATIENTS AND METHODS: Three prepubertal patients, aged 9 (M), 9 (F) and 11 (F) years old, with OI, were treated with 30-60 mg i.v. pamidronate every 6 months over four years. Determinations were made of plasma 1,25-dihydroxycholecalciferol, 25-hydroxycholecalciferol, insulin-like growth factor-I (IGF-I) and its transport protein (IGFBP3), osteocalcin, total alkaline phosphatase and its osseous fraction, and parathormone (PTH) at baseline and after every pamidronate infusion, Densitometry and X-ray of the vertebral column were performed at the same intervals. RESULTS: Significant reductions of number of bone fractures and pain were observed in all patients, despite lack of any modification in biochemical parameters. Lumbar X-ray and densitometry showed a striking improvement by the end of the treatment period. CONCLUSION: Pamidronate seems to be useful in the treatment of patients with osteogenesis imperfecta.     

Effect of intravenous pamidronate therapy on everyday activities in children with osteogenesis imperfecta

AIM: To evaluate the effect of intravenous pamidronate therapy on everyday activities, well-being, skeletal pain and bone density in children with osteogenesis imperfecta (OI). METHODS: In a prospective observational study, monthly intravenous pamidronate infusions were given to 43 children (aged 4 months-16 years) with different severity and form of OI. Outcome measures included the Pediatric Evaluation of Disability Inventory (PEDI), a score of well-being, registration of days with pain and bone density measured by using dual energy X-ray absorptiometry (DXA). Data were collected before and after the first year of treatment. RESULTS: Self-care and mobility measured by PEDI increased significantly in both the Functional Skill scale and in the Caregiver Assistance scale. The youngest children improved more than the older ones according to the PEDI. The days with skeletal pain were reduced and both well-being and bone density increased. CONCLUSIONS: Intravenous treatment with bisphosphonates influenced health status, according to the International Classification of Functioning, Disability and Health (ICF). This group of 43 children experienced beneficial effects on everyday activities, skeletal pain, well-being and bone density.     

Beneficial effect of long term intravenous bisphosphonate treatment of osteogenesis imperfecta

Aim: To find an effective symptomatic treatment for osteogenesis imperfecta (OI). Methods: In a prospective observational study disodium pamidronate (APD) was given as monthly intravenous infusions to 28 children and adolescents (aged 0.6–18 years) with severe OI or a milder form of the disease, but with spinal compression fractures. Results: During treatment for 2–9 years, dual energy x ray absorptiometry measurements of the total body and of the lumbar spine showed a gradual increase in bone density. All bone metabolism variables in serum (alkaline phosphatase, osteocalcin, procollagen 1 C-terminal peptide, collagen 1 teleopeptide) and urine (deoxypyridinoline) indicated that there was a decrease in bone turnover. All patients experienced beneficial effects and the younger patients reported a major improvement in wellbeing, pain, and mobility without significant side effects. Vertebral remodelling was also seen. Conclusions: APD seems to be an efficient symptomatic treatment for children and adolescents with OI.     

Cyclic pamidronate infusion improves bone mineralisation and reduces fracture incidence in osteogenesis imperfecta

A prospective open study was performed to determine the efficacy and safety of pamidronate in improving bone mineralisation and reducing fracture incidence in osteogenesis imperfecta (OI). Intravenous pamidronate was administered at 1.5 mg/kg bi-monthly to six children with OI, over 12-23 months. The number of fractures decreased from median of 3 (range 1-12) to 0 fractures/year (range 0-4) (P<0.05). After 12 months of treatment, there was significant improvement in areal bone mineral density (BMD) z-scores of the lumbar spine from median of -2.40 (range -3.20 to -1.67) to -1.90 (range -2.38 to -0.91) (P<0.05) and in the volumetric BMD which increased from median of 0.095 to 0.146 g/cm3 (P<0.05). Urine N-telopeptide levels (bone resorption marker) decreased from a median of 461.5 bone collagen equivalent/creatinine (BCE/Cr) (range 129-721 BCE/Cr) to 223.5 BCE/Cr (range 107-312 BCE/Cr) (P<0.05) and serum alkaline phosphatase (ALP) (bone formation marker) from a median of 230.0 U/l (range 148-305 U/l) to 133.5 U/l (range 79-233 U/l) (P<0.05), reflecting reduced bone turnover. This may represent a net reduction in bone resorption and provides a biochemical explanation for the increase in bone mineralisation. Height standard deviation scores were not affected and there were no significant adverse effects. CONCLUSION: 1 year cyclical pamidronate is effective and safe in improving bone mineralisation and reducing fracture incidence in osteogenesis imperfecta.     

Radiographic features of bisphosphonate therapy in pediatric patients

BACKGROUND: Pediatric patients are being treated with bisphosphonates for low bone mineral density. Skeletal radiographic findings have been described with bisphosphonates given orally and intravenously. OBJECTIVE: To determine and describe the radiographic findings of cyclic intravenous bisphosphonate therapy in the growing skeleton. MATERIALS AND METHODS: Retrospective review of radiographs of 32 patients with osteogenesis imperfecta or cerebral palsy treated with intravenous bisphosphonates on a quarterly schedule. RESULTS: Principal observations were metaphyseal bands and increased bone mineral density. The bands varied in spacing according to the age of the patient, rate of growth, and the location of the metaphysis. Fractures continued to be seen in patients with osteogenesis imperfecta. CONCLUSION: Cyclic bisphosphonate therapy results in distinctive radiographic findings in the growing skeleton.     

Pamidronate treatment of less severe forms of osteogenesis imperfecta in children

BACKGROUND: Bisphosphonate therapy improves bone quality in children with severe osteogenesis imperfecta (OI). Children with milder phenotypes also have prepubertal fractures, bone pain and reduced bone mass, predisposing them to adult osteoporosis. OBJECTIVE: To evaluate treatment effects of pamidronate in children with mild phenotypes of OI. METHODS: Open label, 2-year observational study of 18 patients, using pamidronate, with clinical, biochemical and radiological monitoring. RESULTS: Over 2 years, bone pain decreased from 16 to 1 patient and disturbed sleep from 12 children to 0. Independent mobility improved from 10 to 17 children. Fracture incidence decreased from 1.6 to 0.5 fractures/child/year. Surgical interventions decreased from a mean 1.3 procedures/patient to 0 in the second year of treatment. Growth velocity remained stable at a mean 4.8 cm/year. Mean lumbar vertebral bone mineral density improved by 40.8%, from 0.375 to 0.528 g/cm2 (p <0.0001), z-score from -3.77 to -2.44 (p <0.0001). Mean vertebral height improved by 17.3%, from 15.6 to 18.38 mm (p = 0.07); plasma alkaline phosphatase decreased from 222 to 169 U/l (p = 0.0009) and urinary deoxypyridinoline crosslinks decreased from 26.7 to 21.8 nmol/mmol creatinine (p = 0.21). Two children with vitamin D insufficiency were concurrently treated. A significant association (r = -0.6, p = 0.008) was shown between age at start of treatment and percentage change in BMD after 2 years. CONCLUSIONS: Pamidronate treatment improves bone quality in children with mild types of OI. It ameliorates clinical symptoms, improves mobility, reduces fracture frequency and thus improves quality of life and in future is likely to reduce the severity and consequences of adult osteoporosis by improved peak bone mass in these children.