Vitamin D and Bone fragility in Individuals with Osteogenesis Imperfecta: A Scoping Review.

Vitamin D affects several body functions, and thus general health, due to its pleiotropic activity. It plays a key role in bone metabolism, and its deficiency impacts bone development, leading to bone fragility. In osteogenesis imperfecta (OI), a group of hereditary connective tissue disorders characterized by bone fragility, additional factors, such as vitamin D deficiency, can affect the expression of the phenotype and aggravate the disorder. The aim of this scoping review was to assess the incidence of vitamin D deficit in OI patients and the association between vitamin D status and supplementation in individuals affected by OI. We searched the PubMed Central and Embase databases and included studies published between January/2000 and October/2022 evaluating vitamin D measurement and status (normal, insufficiency, deficiency) and supplementation for OI. A total of 263 articles were identified, of which 45 were screened by title and abstract, and 10 were included after a full-text review. The review showed that low levels of vitamin D was a frequent finding in OI patients. Vitamin D supplementation was mainly indicated along with drug therapy and calcium intake. Even if widely used in clinical practice, vitamin D supplementation for OI individuals still needs a better characterization and harmonized frame for its use in the clinical setting, as well as further studies focusing on its effect on bone fragility.

Role of rs193922155 in the etiopathogenesis of osteogenesis imperfecta with description of the phenotype: A case report.

INTRODUCTION: Osteogenesis imperfecta (OI) is a disorder of the connective tissue that mainly causes the bones to become excessively brittle. The vast majority of OI cases are associated with mutations in the genes encoding the I alpha. PATIENT CONCERNS: A 57-year-old woman office worker was admitted because of severe, long-lasting pain in the thoracic spine while bending down. She and her daughter have a history of multiple atraumatic fractures form early childhood. DIAGNOSIS: Both women were pre-diagnosed with OI based on their phenotype. The genetic testing has shown single nucleotide polymorphism (rs193922155) in the gene encoding the collagen type I alpha 1 which until now was only likely pathogenic. INTERVENTIONS: Bone mineral density measurement revealed osteoporosis. The mother was prescribed with Vitamin D3 and calcium supplementation, but the daughter does not take any medication. The mother had vertebroplasty performed because of Th 9-12 vertebral body compression fractures. The cardiovascular diseases, spontaneous hematomas, joint dislocations were excluded. OUTCOMES: For mother postoperative pain reduction was achieved. CONCLUSION: To the best of our knowledge, this is the first publication that confirms the pathogenic effect of this mutation and describes the phenotype.

Solanum muricatum Ameliorates the Symptoms of Osteogenesis Imperfecta In Vivo.

Pepino (Solanum muricatum), which is an evergreen plant native to South America, is well-known for its effects in antioxidation, antidiabetic activity, anti-inflammation, and antitumor activity. A previous study in our lab indicated that Solanum muricatum (SM) extract promoted osteogenic differentiation by upregulating Wnt and BMP signaling pathway in rat bone marrow stromal cells. The osteogenesis imperfecta (OI) mouse model was used in order to further discover the osteogenic properties of SM extract in the present research. We utilized microCT analysis to collect bone mass and microarchitectural parameters at vertebrae and at femur metaphysis in OI mice. Raman spectrometry was applied to identify change of bone mineral and matrix composition during SM treatment. Finally, collagen synthesis marker PINP and collagen degradation marker CTX were detected using enzyme immunoassay. SM extract could improve the bone mass and microarchitectural parameters both at vertebrae and at femur metaphysis. It also significantly increased the collagen content by promoting its biosynthesis and inhibiting its degradation. By using heterozygous Col1a1Jrt /+ mice as a model of OI, 6 weeks treatment of SM extract could significantly ameliorate the symptoms in OI mice. Thus, SM holds potential for developing new drugs of bone formation and bone remodeling.

WNT1-associated osteogenesis imperfecta with atrophic frontal lobes and arachnoid cysts.

A rare form of osteogenesis imperfecta (OI) caused by Wingless-type MMTV integration site family 1 (WNT1) mutations combines central nervous system (CNS) anomalies with the characteristic increased susceptibility to fractures. We report an additional case where arachnoid cysts extend the phenotype, and that also confirms the association of intellectual disabilities with asymmetric cerebellar hypoplasia here. Interestingly, if the cerebellum is normal in this disorder, intelligence is as well, analogous to an association with similar delays in a subset of patients with sporadic unilateral cerebellar hypoplasia. Those cases typically appear to represent vascular disruptions, and we suggest that most brain anomalies in WNT1-associated OI have vascular origins related to a role for WNT1 in CNS angiogenesis. This unusual combination of benign cerebellar findings with effects on higher functions in these two situations raises the possibility that WNT1 is involved in the pathogenesis of the associated sporadic cases as well. Finally, our patient reacted poorly to pamidronate, which appears ineffective with this form of OI, so that a lack of improvement is an indication for molecular testing that includes WNT1.

Acute and long-term effects of zoledronate in adult patients with osteogenesis imperfecta. An observational Spanish study with five years of follow-up. / Efectos agudos y a largo plazo del tratamiento con zolendronato en pacientes adultos con osteogénesis imperfecta. Estudio español observacional con 5 años de seguimiento.

Osteogenesis imperfecta (OI) is an inherited disorder that causes low mineral density and bone fragility. Previous studies have shown the efficacy of bisphosphonates to increase bone mineral density (BMD). This study assessed changes over time in BMD and biochemical markers of bone metabolism in adult patients with osteogenesis imperfecta treated with intravenous zoledronic acid and the safety of this treatment. PATIENTS AND METHODS: A prospective, observational study in patients with OI, osteoporosis or osteopenia (T score <-2) who were administered zoledronic acid infusions (4mg IV) every 6 months for three years and annually thereafter. Densitometry was performed annually. Acute changes in complete blood count and calcium, phosphate, and creatinine levels, as well as side effects of the infusion, were recorded 24 and 48h after treatment. Calcium, phosphate, parathyroid hormone (iPTH), 25OH-vitamin D and bone turnover markers (bone alkaline phosphatase, ß-crosslaps and urinary deoxypyridinoline) were measured at baseline and every 12 months. Adverse events and new fractures were recorded. RESULTS: Twenty patients (6 men and 14 women) were treated. Median follow-up time was five years. Calcium levels and platelet counts significantly decreased 24 and 48hours after the first infusion, and the red blood cell count decreased at 24hours. These changes were not clinically relevant. Seven patients experienced a flu-like episode after the first dose. Treatment induced significant increases in BMD in the lumbar spine (6.7%) after 12 months of follow-up (0.791±0.178 vs. 0.791±0.140g/cm2, p=.003) and at three (5.7%) and five years (9%) of follow-up. Femoral neck BMD significantly increased after 3 years (11.1%): 0.648±0.148 vs. 0.720±0.138g/cm2; p=.01. In total hip, increase in BMD (10.1%) was significant after three years of treatment (0.706±0.118 vs. 0.720±0.138, p=.01). There were no significant differences in calcium and 25OH-vitamin D levels during follow-up, phosphorus significantly decreased after one year, and iPTH increased at three years. ß-crosslaps decreased after one year of treatment. Only one patient sustained new fractures. CONCLUSIONS: Zoledronic acid is a convenient, safe, and effective treatment that increases BMD in adult patients with OI.

Interventions for Improving Bone Mineral Density and Reducing Fracture Risk in Osteogenesis Imperfecta: A Mixed Treatment Comparison Network Meta-analysis of Randomized Controlled Clinical Trials.

BACKGROUND: Osteogenesis imperfecta is a rare metabolic disorder associated with reduced mineralization of bone and corresponds to increased fracture risk. We carried out the present network meta-analysis comparing all the medical interventions for osteogenesis imperfecta. METHOD: Electronic databases were searched for randomized controlled clinical trials evaluating the use of drugs in patients with osteogenesis imperfecta. Percent change in BMD was the primary and fracture risk reduction and adverse events were the secondary outcome measures. The weighted mean difference was the pooled estimate for primary outcome and odds ratio with 95% confidence interval for the secondary outcome measures. Direct and mixed treatment comparisons between the interventions were carried out by inverse heterogeneity model. Sub-group analyses were carried out on children, adults and within bisphosphonate groups. The trial sequential analysis was carried out for the comparison of oral bisphosphonates with placebo. RESULTS: A total of 16 studies were included evaluating oral and intravenous bisphosphonates, teriparatide, anti-sclerostin antibody, high dose vitamin D and recombinant growth hormone (rGH) combined with intravenous bisphosphonates. Oral bisphosphonates and teriparatide were observed with a statistically significant increase in BMD compared to placebo. Also, only oral bisphosphonates were associated with significant reduction in the fracture risk but when the alpha error was adjusted for the information accrued till date as well as when the results of a trial were excluded, no significant difference was observed. Either low or very low quality was observed for pooled estimates of the key comparisons. CONCLUSION: Oral bisphosphonates and teriparatide significantly increase BMD but are not associated with fracture risk reduction. Of the available interventions, oral bisphosphonates could perform better than others in osteogenesis imperfecta. This evidence should be considered preliminary and may change with future head-to-head clinical trials.

Effect of high-dose vitamin D supplementation on bone density in youth with osteogenesis imperfecta: A randomized controlled trial.

Osteogenesis imperfecta (OI) is a heritable condition characterized by fragile bones. Our previous studies indicated that serum 25-hydroxyvitamin D (25OHD) concentrations were positively associated with lumbar spine areal bone mineral density (LS-aBMD) in children and adolescents with OI. Here we assessed whether one year of high-dose vitamin D supplementation results in higher LS-aBMD z-scores in youth with OI. A one-year double-blind randomized controlled trial conducted at a pediatric orthopedic hospital in Montreal, Canada. Sixty patients (age: 6.0 to 18.9years; 35 female) were randomized in equal numbers to receive either 400 or 2000international units (IU) of vitamin D, stratified according to baseline bisphosphonate treatment status and pubertal stage. At baseline, the average serum 25OHD concentration was 65.6nmol/L (SD 20.4) with no difference between treatment groups (p=0.77); 21% of patients had results <50nmol/L. Vitamin D supplementation was associated with higher serum 25OHD concentrations in 90% of participants. The increase in mean 25OHD was significantly higher (p=0.02) in the group receiving 2000IU of vitamin D (mean [95% CI]=30.5nmol/L [21.3; 39.6]) than in the group receiving 400IU (15.2nmol/L [6.4; 24.1]). No significant differences in LS-aBMD z-score changes were detected between treatment groups. Thus, supplementation with vitamin D at 2000IU increased serum 25OHD concentrations in children with OI more than supplementation with 400IU. However, in this study where about 80% of participants had baseline serum 25OHD concentrations ≥50nmol/L, this difference had no detectable effect on LS-aBMD z-scores.

[PREPARATIONS OF PAMIDRONOVIC ACID IN COMPLEX TREATMENT ON OSTEOGENESIS IMPERFECTA].

Modern view of drug therapy in the complex treatment of orthopedic manifestations of osteogenesis imperfecta (OI) was submitted. Developed and tested system of drug correction of structural and functional state of bone tissue (BT) using drugs pamidronovic acid, depending on osteoporosis severity and type of disease. Such therapy is appropriate to apply both independently and in conjunction with surgery to correct deformations of long bones of the lower extremities. Effectiveness and feasibility of the proposed methods of drug therapy was proved, most patients resume features walking and support.

Short-Term Safety of Zoledronic Acid in Young Patients With Bone Disorders: An Extensive Institutional Experience.

CONTEXT: Zoledronic acid (ZA) is increasingly used in young patients with bone disorders. However, data related to the safety of ZA administration in this population are limited. OBJECTIVE: The study aimed to characterize the short-term safety profile of ZA and identify risk factors for ZA-related adverse events (AEs) in young patients. DESIGN, SETTING, AND PARTICIPANTS: This was a retrospective chart review of inpatients and outpatients less than 21 years old who received at least one ZA infusion between July 2010 and January 2014 at The Children's Hospital of Philadelphia. RESULTS: Eighty-one patients (56% male; median age, 12 y; age at first infusion, 0.5 to 20 y) with diverse skeletal disorders received a total of 204 infusions. The most common indications were osteoporosis (33% of cohort) and osteogenesis imperfecta (27.2%). The median ZA dose was 0.025 mg/kg (interquartile range, 0.025-0.05); the median dosing interval was 6 months (range, 1 to 25.6 mo). AEs were mild and more common after the first ZA infusion in patients with no previous bisphosphonate exposure: hypophosphatemia (25.2% of infusions), acute phase reactions (19.1%), and hypocalcemia (16.4%). Symptomatic hypocalcemia requiring iv calcium occurred after two infusions. ZA dose was significantly associated with hypophosphatemia, but not other AEs. Hypocalcemia was more common in patients with high bone turnover as assessed by preinfusion alkaline phosphatase levels. AEs were not associated with diagnosis, baseline serum calcium, or calcium/calcitriol supplementation. CONCLUSION: Acute AEs related to ZA infusion in youths are common, occur principally after the first ZA infusion in bisphosphonate-naive patients, and are typically mild and easily managed. Future prospective studies are needed to determine the potential long-term risks, as well as benefits, of ZA therapy in the pediatric population.

Adult Brtl/+ mouse model of osteogenesis imperfecta demonstrates anabolic response to sclerostin antibody treatment with increased bone mass and strength.

UNLABELLED: Treatments to reduce fracture rates in adults with osteogenesis imperfecta are limited. Sclerostin antibody, developed for treating osteoporosis, has not been explored in adults with OI. This study demonstrates that treatment of adult OI mice respond favorably to sclerostin antibody therapy despite retention of the OI-causing defect. INTRODUCTION: Osteogenesis imperfecta (OI) is a heritable collagen-related bone dysplasia, characterized by brittle bones with increased fracture risk. Although OI fracture risk is greatest before puberty, adults with OI remain at risk of fracture. Antiresorptive bisphosphonates are commonly used to treat adult OI, but have shown mixed efficacy. New treatments which consistently improve bone mass throughout the skeleton may improve patient outcomes. Neutralizing antibodies to sclerostin (Scl-Ab) are a novel anabolic therapy that have shown efficacy in preclinical studies by stimulating bone formation via the canonical wnt signaling pathway. The purpose of this study was to evaluate Scl-Ab in an adult 6 month old Brtl/+ model of OI that harbors a typical heterozygous OI-causing Gly > Cys substitution on Col1a1. METHODS: Six-month-old WT and Brtl/+ mice were treated with Scl-Ab (25 mg/kg, 2×/week) or Veh for 5 weeks. OCN and TRACP5b serum assays, dynamic histomorphometry, microCT and mechanical testing were performed. RESULTS: Adult Brtl/+ mice demonstrated a strong anabolic response to Scl-Ab with increased serum osteocalcin and bone formation rate. This anabolic response led to improved trabecular and cortical bone mass in the femur. Mechanical testing revealed Scl-Ab increased Brtl/+ femoral stiffness and strength. CONCLUSION: Scl-Ab was successfully anabolic in an adult Brtl/+ model of OI.

The intake of Yam (Dioscorea bulbifera Linn) attenuated the hyperglycemia and the bone fragility in female diabetic rats / El consumo de Ñame (Dioscorea bulbifera Linn) atenuó la hiperglucemia y la fragilidad ósea en ratas diabéticas

Introduction: Diabetic patients have a higher risk to osteoporotic fractures. Foods, such as yam, to oppose hyperglycemia, has been used to treatment of diabetes. Objective: The goal was assess the role of Brazilian yam (Dioscorea bulbifera) on glycemia and bone parameters of female diabetic rats. Methods: Female Wistar rats with 3 months age were allocated in three groups. Control group (C, n = 6),treated with normal fat diet. Diabetic rats treated withhigh-fat diet without (DM, n = 8) and with (DMY, n = 8) liofilized yam flour. After 5 weeks of the experiment, serum glucose and insulin, pancreas mass, number and area of pancreas islets were quantified. And femur parameters were analyzed by dual-energy X-ray absorptiometry(DXA) and computed tomography (CT).Results: Differences were considered significant ifP<0.05. Diabetic groups showed lower (P < 0.05): femur and pancreas mass, area of the pancreatic islets and insulin. However, DMY showed lower (-10%, P < 0.05)concentrations of glucose to DM group. Femur, by DXA, showed lower bone mineral density, content and area in the DM group. While the DMY group showed greater(+27%, P < 0.05) radiodensity of femoral head when compared to DM group. Discussion: Brazilian yam flour supplement did not fix a defect, but alleviated the consequences of the experimental diabetic disease. It showed results to control the rise in blood glucose levels in diabetic rats, suggesting protection in oxidative agents and postpone harm in the bone. Conclusion: Considering all the findings of the present study, our results suggest that yam flour does act producing benefits in the experimental diabetes (AU)

Introducción: Los pacientes diabéticos tienen un mayor riesgo de fracturas osteoporóticas. Los alimentos, como el ñame, para oponerse a la hiperglucemia, se ha utilizado para el tratamiento de la diabetes. Objetivos: El objetivo era evaluar el papel de ñame brasileño(Dioscorea bulbifera) sobre la glucemia y el hueso parámetros de ratas diabéticas hembra. Métodos: Ratas Wistar hembra con 3 meses de edad fueron asignados en tres grupos. El grupo de control (C, n= 6), tratados con dieta normal de la grasa. Las ratas diabéticas tratadas con dieta alta en grasas y sin (DM, n = 8)y con (DMY, n = 8) harina de ñame liofilizado. Después se cuantificaron 5 semanas del experimento, la glucosa y la insulina en suero, la masa páncreas, el número y el área de islotes del páncreas. Y los parámetros de fémur fueron analizados por absorciometría de rayos X de energía dual(DXA) y la tomografía computarizada (CT).Resultados: Las diferencias se consideraron significativas si P < 0,05. Grupos diabéticos mostraron menor (P <0,05): el fémur y la masa páncreas, el área de los islotes pancreáticos y la insulina. Sin embargo, DMY mostró inferior (-10%, P < 0,05) concentraciones de glucosa al grupo DM. Fémur, por DXA, mostró menor densidad mineral ósea, el contenido y el área en el grupo de DM. Mientras que el grupo DMY mostró mayor (27%, P <0,05) radiodensidad de la cabeza femoral en comparación con el grupo de DM. Discusión: Suplemento de harina de ñame brasileña no fijó un defecto, pero alivia las consecuencias de la enfermedad diabética experimental. Se mostró resultados para controlar el aumento de los niveles de glucosa en sangre en ratas diabéticas, lo que sugiere la protección en agentes oxidantes y posponer daño en el hueso. Conclusión: Teniendo en cuenta todos los resultados de este estudio, nuestros resultados sugieren que la harina deñame actúa de producir beneficios en la diabetes experimental (AU)

Comparable outcomes in fracture reduction and bone properties with RANKL inhibition and alendronate treatment in a mouse model of osteogenesis imperfecta.

UNLABELLED: We report a direct comparison of receptor activator of nuclear factor kappa B ligand (RANKL) inhibition (RANK-Fc) with bisphosphonate treatment (alendronate, ALN) from infancy through early adulthood in a mouse model of osteogenesis imperfecta. Both ALN and RANK-Fc decreased fracture incidence to the same degree with increases in metaphyseal bone volume via increased number of thinner trabeculae. INTRODUCTION: The potential therapeutic benefit of RANKL inhibitors in osteogenesis imperfecta (OI) is under investigation. We report a direct comparison of RANKL inhibition (RANK-Fc) with bisphosphonate treatment (ALN) from infancy through early adulthood in a model of OI, the oim/oim mouse. METHODS: Two-week-old oim/oim, oim/+, and wildtype (+/+) mice were treated with RANK-Fc 1.5 mg/kg twice per week, ALN 0.21 mg/kg/week or saline (n = 12-20 per group) for 12 weeks. RESULTS: ALN and RANK-Fc both decreased fracture incidence (9.0 ± 3.0 saline 4.4 ± 2.7 ALN, 4.3 ± 3.0 RANK-Fc fractures per mouse). Serum TRACP-5b activity decreased to 65% after 1 month in all treated mice, but increased sacrifice with RANK-Fc to 130-200% at sacrifice. Metaphyseal density was significantly increased with ALN in +/+ and oim/oim mice (p < 0.05) and tended to increase with RANK-Fc in +/+ mice. No changes in oim/oim femur biomechanical parameters occurred with treatment. Both ALN and RANK-Fc significantly increased trabecular number (3.73 ± 0.77 1/mm for oim/oim saline vs 7.93 ± 0.67 ALN and 7.34 ± 1.38 RANK-Fc) and decreased trabecular thickness (0.045 mm ± 0.003 for oim/oim saline vs 0.034 ± 0.003 ALN and 0.032 ± 0.002 RANK-Fc) and separation in all genotypes (0.28 ± 0.08 mm for oim/oim saline vs 0.12 ± 0.010 ALN and 13 ± 0.03 RANK-Fc)., with significant increase in bone volume fraction (BVF) with ALN, and a trend towards increased BVF in RANK-Fc. CONCLUSION: Treatment of oim/oim mice with either a bisphosphonate or a RANK-Fc causes similar decreases in fracture incidence with increases in metaphyseal bone volume via increased number of thinner trabeculae.

Neridronic acid for the treatment of bone metabolic diseases.

Neridronic acid (6-amino-1-idroxyesilidene-1,1-bisphosphonate) is a nitrogen-containing bisphosphonate licensed in Italy for the treatment of osteogenesis imperfecta and Paget's disease of bone. The pharmacodynamic profile is similar to that of other nitrogen-containing bisphosphonates and is characterized by its high affinity for bone tissue particularly at sites undergoing a process of remodeling. In growing children affected by osteogenesis imperfect, neridronic acid rapidly increases bone mineral density as measured by dual X-ray absortiometry and this is associated with a significant decrease in fracture cumulative number. Similar results have been obtained also in newborns (< 12 month old) and in adult patients. In Paget's disease of bone, 200 mg intravenous neridronic acid is associated with a 65% rate of full remission and a biochemical response (decrease of > 75% of bone turnover markers) in 95% of the patients. Neridronic acid treatment has been reported to be effective also in other skeletal diseases such as osteoporosis, algodystrophy, hypercalcemia of malignancy and bone metastasis. Neridronic acid has been developed only for parenteral use, and it is the only one used as intramuscular injection. This avoids all the limitations of oral bisphosphonates and may be offered for a home treatment with simple nursing assistance.

Alternative indications for bisphosphonate therapy.

Bisphosphonates are currently used in the treatment of osteoporosis (postmenopausal and steroid-induced), hypercalcemia of malignancy, Paget's disease of bone, multiple myeloma, and skeletally related events associated with metastatic bone disease in breast, prostate, lung, and other cancers. There are, however, numerous other conditions where a decrease in bone remodeling by bisphosphonates might aid in disease management. The focus of this review will be to discuss a select group of conditions for which bisphosphonate therapy may be efficacious. In this review we present several cases where bisphosphonates have been used as a primary or adjunctive treatment for giant cell lesions of the jaws. Use of bisphosphonate therapy for giant cell tumors of the appendicular skeleton, pediatric osteogenesis imperfecta, fibrous dysplasia, Gaucher's disease, and osteomyelitis will be discussed. Finally, we will review previous in vivo studies on the use of bisphosphonates to augment integration and to treat osteolysis surrounding failing orthopedic implants.

Alendronate treatment in children with osteogenesis imperfecta.

BACKGROUND: Recent studies reported beneficial effect of cyclical intravenous administration of pamidronate in children and adolescents with osteogenesis imperfecta (OI). However, this treatment requires frequent hospital admissions and is relatively expensive. Alendronate is an oral bisphosphonate effectively used in adults with osteoporosis. Experience with alendronate treatment in children with OI is limited. AIMS: To report our experience with alendronate in children with OI. METHODS: 12 children with OI (7 with type I, 4 with type III and 1 with type IV; 7 boys, 5 girls) aged 1.8 to 15.4 years (7.9+/-; 4.4 yrs) were included in this retrospective study. The patients were treated with alendronate in a dose of 5-10 mg/day along with calcium (500 mg/day) and vitamin D (400-1000 IU/day) supplements for 19.8+/-11.3 months (range: 7-46 months). Serum calcium (Ca), phosphorus (P), alkaline phosphatase (ALP), osteocalcin (OC), pyrilinks-D and urinary Ca/Cr ratio were studied 3 monthly and bone mineral density (BMD) by DXA on 6-12 monthly basis. RESULTS: Fracture rate of the patients significantly decreased after treatment (1.2+/-1.5 vs. 0.16+/-0.32 per year, P<0.05). Treatment improved bone density in each individual case. Z-scores of lumbar DXA (L2-L4) significantly increased during treatment (-4.60+/-1.30 vs - 2.47+/-1.52, P< 0.05). Urinary pyrilinks-D decreased with treatment (90.8+/-136.3 vs. 35.1+/-29.9, P< 0.05). Serum Ca, P, ALP, OC and urinary Ca/Cr did not change significantly during treatment. CONCLUSION: We conclude that alendronate is effective, safe and practical alternative to intravenous bisphosphonates in treatment of children with OI.

New trends in the treatment of osteogenesis imperfecta type III - own experience.

INTRODUCTION: Osteogenesis imperfecta (OI) is a genetic disorder caused by a mutation in the genes that encode the chains of type I collagen. Clinical manifestations include increased bone fragility and blue sclerae. OI type III is the most severe form with fractures occurring already in utero. Fracture immobilisation and orthopaedic surgery are the mainstay of treatment for patients with OI, and are combined with rehabilitation and bisphosphonate therapy. PATIENTS AND METHODS: The study involved 8 children with osteogenesis imperfecta type III, aged 1 month to 6 years. All of them were treated with cyclic intravenous infusions of pamidronate. Laboratory studies conducted before and after each 3-day cycle of pamidronate therapy included complete blood count, serum calcium, phosphorus, magnesium, osteocalcin, and calcium/creatinine index in morning urine and collagen type I cross-linked N-telopeptide (NTx). Infant total body densitometric scans were obtained in 5/8 patients. RESULTS: Patients were treated for periods of 3-58 months. Fracture rates decreased with treatment in all patients compared to the prenatal period. Pamidronate also slowed down bone turnover, and particularly the resorption rate. The most common side effects during treatment included hypocalcaemia (7/8 patients) and fever (up to 39 degrees C) after the first cycle of treatment. CONCLUSION: Symptomatic bisphosphonate therapy in children with osteogenesis imperfecta ameliorated the clinical course (decreased bone pain and reduced incidence of fractures). Pamidronate therapy had a positive impact on functional parameters such as independence in everyday activities and better mobility. The treatment was safe.

Osteogenesis imperfecta type VI in childhood and adolescence: effects of cyclical intravenous pamidronate treatment.

Cyclical intravenous treatment with pamidronate is of clinical benefit in children with moderate to severe osteogenesis imperfecta (OI) types I, III and IV, but there is no information on the effects of this treatment on the newly described OI type VI. Here, we report on the results of 3 years of pamidronate treatment in 10 children and adolescents with OI type VI (age range 0.8 to 14.5 years, three girls). Treatment effects were compared to those of 10 patients with OI types I, III, and IV, who were matched for age and disease severity (based on height and lumbar spine areal bone mineral density). During pamidronate therapy, lumbar spine areal bone mineral density z scores increased and lumbar spine vertebral bodies improved in shape. Iliac bone histomorphometry showed a tendency to higher cortical thickness (+53%, P=0.06) but the mineralization defect, a characteristic feature of OI type VI, did not change during pamidronate treatment. Annualized fracture incidence decreased from 3.1 per year before treatment to 1.4 fractures per year during treatment (P<0.05). Regarding mobility, the Pediatric Evaluation of Disability Inventory gross motor score increased by 42% during pamidronate treatment (P<0.005). Significant improvements were also found for age-related z scores of maximal isometric grip force. In comparison to the OI control group, the fracture incidence was higher and the gross motor scores were lower in OI type VI, both before and after pamidronate treatment (P<0.05 for each parameter). No differences were found between the groups for changes in densitometric measures and cortical thickness during pamidronate treatment. Our results suggest that 3 years of intravenous pamidronate therapy led to improvements in bone mineral mass, gross motor function, muscle force and fracture incidence in patients with OI type VI. However, the gains in mobility scores and reductions in fracture incidence during pamidronate treatment are less than in other OI types.

Benefits of pamidronate in children with osteogenesis imperfecta: an open prospective study.

OBJECTIVES: To study the efficacy of pamidronate in children with osteogenesis imperfecta (OI). PATIENTS AND METHODS: Twenty-nine patients (median age 8.7 years), were given pamidronate in cyclic infusions of 3 days. Patients received 3-13 cycles (median 6), at a dose of 0.5 mg/kg/day in infants (below 2 years of age) and 1 mg/kg/day in children (2 years and older). The interval time between cycles was 2 months in infants and 4 months in children. The median follow-up was 16 months. All patients received daily supplementation of calcium, vitamin D and physical rehabilitation. Assessments were performed at baseline and before each cycle. Fracture rate under treatment was compared to the one in the pre-treatment period. RESULTS: Pain decreased after the first infusion cycle (P < 0.0001). The median of fracture incidence decreased from 15 to 0.5 per year in infants and from 2.0 to 1 per year in children (P = 0.04). Alkaline phosphatase decreased by 31.2% and N-telopeptide collagen cross-links decreased by 61.8% (P < 0.001). Bone mineral density (BMD) of the spine increased by a median of 55.4% (P < 0.001). Z-scores increased from a median of -4.7 to -2.6 (P < 0.001). The femoral neck, BMD increased by a median of 16%. The area of the first four lumbar vertebrae increased by a median of 21.5% (P < 0.001). No adverse effect on growth or on fracture healing was observed. Side effects were symptomatic hypocalcemia in one infant, and the transient acute phase reaction. CONCLUSION: Pamidronate increases BMD, decreases bone remodeling markers, pain and fracture rate in infants and children with OI.

Skeletal effects and functional outcome with olpadronate in children with osteogenesis imperfecta: a 2-year randomised placebo-controlled study.

BACKGROUND: Non-randomised studies have suggested beneficial effects of bisphosphonates in osteogenesis imperfecta. We assessed the effects of oral olpadronate in children with this disorder in a randomised double-blind placebo-controlled trial. METHODS: 34 children recruited from the Dutch national centre for osteogenesis imperfecta were randomly assigned olpadronate (10 mg/m2 daily; n=16) or placebo (n=18) for 2 years. All children also received calcium and vitamin D supplements. Primary endpoints were incident fractures of long bones and changes in bone mineral content (BMC), bone mineral density (BMD), and functional outcome. Anthropometry, vertebral height, and urinary markers of bone resorption were also studied. Analyses were by intention to treat. FINDINGS: Fracture follow-up was complete for all the children, including two who withdrew from the study (one from each group). Olpadronate treatment was associated with a 31% reduction in relative risk of fracture of long bones (hazard ratio 0.69 [95% CI 0.52-0.91], p=0.01). The olpadronate group showed significantly greater increases than the placebo group in spinal BMC (difference between groups 2.24 g/year [0.20-4.29], p=0.03) and spinal BMD (difference between groups 0.054 g/cm2 per year [0.012-0.096], p=0.01). There were no detectable effects on functional outcome, anthropometrics, or vertebral height and no differences between the groups in changes in urinary markers of bone resorption. INTERPRETATION: Oral treatment with olpadronate at a daily dose of 10 mg/m2 results in a reduction of fracture risk of long bones in children with osteogenesis imperfecta. However, the issue of whether bisphosphonates will alter the natural course of osteogenesis imperfecta remains unresolved, and further studies are needed.

Alendronate treatment for infants with osteogenesis imperfecta: demonstration of efficacy in a mouse model.

Recent non-placebo-controlled studies of the bisphosphonate pamidronate have shown it to be effective in reducing fractures and improving bone density in infants and children with osteogenesis imperfecta (OI). To evaluate the effects of bisphosphonate treatment in a controlled study, the oim/oim mouse model of OI was studied. Nursing infant mouse pups (approximately 2 wk old) with moderate to severe OI (oim/oim mouse) and age- and background-matched control mice (+/+) were treated either with the third-generation bisphosphonate alendronate (ALN), or with saline. Fracture risk, bone quality, and growth were evaluated over a 12-wk treatment period. ALN at a dose of 0.03 mg/kg/d or saline was administered via s.c. injection to infant oim/oim and wild-type (+/+) mice from 2 to 14 wk of age (n = 20 per subgroup). The average number of fractures sustained by the ALN-treated oim/oim mice was reduced significantly compared with the untreated oim/oim mice (0.7 +/- 0.7 fractures/mouse versus 2.0 +/- 0.2 fractures/mouse). Bone density increased significantly in the femur and the spine with treatment (2.0 +/- 0.5 versus 1.2 +/- 0.5 in femur and 2.1 +/- 0.5 versus1.6 +/- 0.5 in spine). Histologic evaluation revealed the percentage of metaphyseal tibial bone increased significantly with treatment in both +/+ and oim/oim mice. Mechanical testing revealed an increase in structural stiffness for both treated +/+ and oim/oim mice compared with untreated animals. None of the material properties examined were significantly altered with treatment, nor was spinal curvature affected. Weight gain and long bone growth were comparable in the treated and untreated oim/oim mice. In wild-type mice, femur lengths were significantly shorter in the treated mice compared with untreated counterparts. This animal study demonstrates that treatment of OI in mice as early as 2 wk of age with ALN appears to be effective in reducing fractures and increasing bone properties. Based on the data from this study, ALN therapy in infants with OI should prove to be effective.