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Prevention of osteomalacia rests on having an adequate intake of vitamin D and calcium. Vitamin D3 Supplementation is often needed due to the scarcity of Vitamin D sources in the modern diet.
The medication(s) listed below have been approved by the Food and Drug Administration (FDA) as orphan products for treatment of this condition. Learn more orphan products.
Nutritional osteomalacia responds well to administration of 2,000-10,000 IU of vitamin D3 by mouth daily. Vitamin D3 (cholecalciferol) is typically absorbed more readily than vitmin D2 (ergocalciferol). Osteomalacia due to malabsorption may require treatment by injection or daily oral dosing of significant amounts of vitamin D3.
The only effective line of treatment for malignant infantile osteopetrosis is hematopoietic stem cell transplantation. It has been shown to provide long-term disease-free periods for a significant percentage of those treated; can impact both hematologic and skeletal abnormalities; and has been used successfully to reverse the associated skeletal abnormalities.
Radiographs of at least one case with malignant infantile osteopetrosis have demonstrated bone remodeling and recanalization of medullar canals following hematopoietic stem cell transplantation. This favorable radiographic response could be expected within one year following the procedure - nevertheless, primary graft failure can prove fatal.
Oral phosphate, 9, calcitriol, 9; in the event of severe bowing, an osteotomy may be performed to correct the leg shape.
Treatment in fibrous dysplasia is mainly palliative, and is focused on managing fractures and preventing deformity. There are no medications capable of altering the disease course. Intravenous bisphosphonates may be helpful for treatment of bone pain, but there is no clear evidence that they strengthen bone lesions or prevent fractures. Surgical techniques that are effective in other disorders, such as bone grafting, curettage, and plates and screws, are frequently ineffective in fibrous dysplasia and should be avoided. Intramedullary rods are generally preferred for management of fractures and deformity in the lower extremities. Progressive scoliosis can generally be managed with standard instrumentation and fusion techniques. Surgical management in the craniofacial skeleton is complicated by frequent post-operative FD regrowth, and should focus on correction of functional deformities. Prophylactic optic nerve decompression increases the risk of vision loss and is contraindicated.
Managing endocrinopathies is a critical component of management in FD. All patients with fibrous dysplasia should be evaluated and treated for endocrine diseases associated with McCune–Albright syndrome. In particular untreated growth hormone excess may worsen craniofacial fibrous dysplasia and increase the risk of blindness. Untreated hypophosphatemia increases bone pain and risk of fractures.
As of October 2015, asfotase alfa (Strensiq) has been approved by the FDA for the treatment of hypophosphatasia. Current management consists of palliating symptoms, maintaining calcium balance and applying physical, occupational, dental and orthopedic interventions, as necessary.
- Hypercalcemia in infants may require restriction of dietary calcium or administration of calciuretics. This should be done carefully so as not to increase the skeletal demineralization that results from the disease itself. Vitamin D sterols and mineral supplements, traditionally used for rickets or osteomalacia, should not be used unless there is a deficiency, as blood levels of calcium ions (Ca2+), inorganic phosphate (Pi) and vitamin D metabolites usually are not reduced.
- Craniosynostosis, the premature closure of skull sutures, may cause intracranial hypertension and may require neurosurgical intervention to avoid brain damage in infants.
- Bony deformities and fractures are complicated by the lack of mineralization and impaired skeletal growth in these patients. Fractures and corrective osteotomies (bone cutting) can heal, but healing may be delayed and require prolonged casting or stabilization with orthopedic hardware. A load-sharing intramedullary nail or rod is the best surgical treatment for complete fractures, symptomatic pseudofractures, and progressive asymptomatic pseudofractures in adult hypophosphatasia patients.
- Dental problems: Children particularly benefit from skilled dental care, as early tooth loss can cause malnutrition and inhibit speech development. Dentures may ultimately be needed. Dentists should carefully monitor patients’ dental hygiene and use prophylactic programs to avoid deteriorating health and periodontal disease.
- Physical Impairments and pain: Rickets and bone weakness associated with hypophosphatasia can restrict or eliminate ambulation, impair functional endurance, and diminish ability to perform activities of daily living. Nonsteroidal anti-inflammatory drugs may improve pain-associated physical impairment and can help improve walking distance]
- Bisphosphonate (a pyrophosphate synthetic analog) in one infant had no discernible effect on the skeleton, and the infant’s disease progressed until death at 14 months of age.
- Bone marrow cell transplantation in two severely affected infants produced radiographic and clinical improvement, although the mechanism of efficacy is not fully understood and significant morbidity persisted.
- Enzyme replacement therapy with normal, or ALP-rich serum from patients with Paget’s bone disease, was not beneficial.
- Phase 2 clinical trials of bone targeted enzyme-replacement therapy for the treatment of hypophosphatasia in infants and juveniles have been completed, and a phase 2 study in adults is ongoing.
In season 2 of the USA Network series Royal Pains, Reshma Shetty (as Divya Katdare) diagnoses a storm chaser (Jamie Ray Newman) with recurring fractures to have tumor-induced osteomalacia.
There is no cure, although curative therapy with bone marrow transplantion is being investigated in clinical trials. It is believed the healthy marrow will provide the sufferer with cells from which osteoclasts will develop. If complications occur in children, patients can be treated with vitamin D. Gamma interferon has also been shown to be effective, and it can be associated to vitamin D. Erythropoetin has been used to treat any associated anemia. Corticosteroids may alleviate both the anemia and stimulate bone resorption. Fractures and osteomyelitis can be treated as usual. Treatment for osteopetrosis depends on the specific symptoms present and the severity in each person. Therefore, treatment options must be evaluated on an individual basis. Nutritional support is important to improve growth and it also enhances responsiveness to other treatment options. A calcium-deficient diet has been beneficial for some affected people.
Treatment is necessary for the infantile form:
- Vitamin D (calcitriol) appears to stimulate dormant osteoclasts, which stimulates bone resorption
- Gamma interferon can have long-term benefits. It improves white blood cell function (leading to fewer infections), decreases bone volume, and increases bone marrow volume.
- Erythropoietin can be used for anemia, and corticosteroids can be used for anemia and to stimulate bone resorption.
Bone marrow transplantation (BMT) improves some cases of severe, infantile osteopetrosis associated with bone marrow failure, and offers the best chance of longer-term survival for individuals with this type.
In pediatric (childhood) osteopetrosis, surgery is sometimes needed because of fractures. Adult osteopetrosis typically does not require treatment, but complications of the condition may require intervention. Surgery may be needed for aesthetic or functional reasons (such as multiple fractures, deformity, and loss of function), or for severe degenerative joint disease.
The long-term-outlook for people with osteopetrosis depends on the subtype and the severity of the condition in each person.The severe infantile forms of osteopetrosis are associated with shortened life expectancy, with most untreated children not surviving past their first decade. seems to have cured some infants with early-onset disease. However, the long-term prognosis after transplantation is unknown. For those with onset in childhood or adolescence, the effect of the condition depends on the specific symptoms (including how fragile the bones are and how much pain is present). Life expectancy in the adult-onset forms is normal.
Resection of the tumor is the ideal treatment and results in correction of hypophosphatemia (and low calcitriol levels) within hours of resection. Resolution of skeletal abnormalities may take many months.
If the tumor cannot be located, treatment with calcitriol (1-3 µg/day) and phosphorus (1-4 g/day in divided doses) is instituted. Tumors which secrete somatostatin receptors may respond to treatment with octreotide. If hypophosphatemia persists despite calcitriol and phosphate supplementation, administration of cinacalcet has been shown to be useful
Certain medications have been associated with an increase in osteoporosis risk; only glucocorticosteroids and anticonvulsants are classically associated, but evidence is emerging with regard to other drugs.
- Steroid-induced osteoporosis (SIOP) arises due to use of glucocorticoids – analogous to Cushing's syndrome and involving mainly the axial skeleton. The synthetic glucocorticoid prescription drug prednisone is a main candidate after prolonged intake. Some professional guidelines recommend prophylaxis in patients who take the equivalent of more than 30 mg hydrocortisone (7.5 mg of prednisolone), especially when this is in excess of three months. Alternate day use may not prevent this complication.
- Barbiturates, phenytoin and some other enzyme-inducing antiepileptics – these probably accelerate the metabolism of vitamin D.
- L-Thyroxine over-replacement may contribute to osteoporosis, in a similar fashion as thyrotoxicosis does. This can be relevant in subclinical hypothyroidism.
- Several drugs induce hypogonadism, for example aromatase inhibitors used in breast cancer, methotrexate and other antimetabolite drugs, depot progesterone and gonadotropin-releasing hormone agonists.
- Anticoagulants – long-term use of heparin is associated with a decrease in bone density, and warfarin (and related coumarins) have been linked with an increased risk in osteoporotic fracture in long-term use.
- Proton pump inhibitors – these drugs inhibit the production of stomach acid; this is thought to interfere with calcium absorption. Chronic phosphate binding may also occur with aluminium-containing antacids.
- Thiazolidinediones (used for diabetes) – rosiglitazone and possibly pioglitazone, inhibitors of PPARγ, have been linked with an increased risk of osteoporosis and fracture.
- Chronic lithium therapy has been associated with osteoporosis.
In circumstances where other pathologies are excluded (for example, cancer), a pathologic fracture is diagnostic of osteoporosis irrespective of bone mineral density.
Pathologic fractures in children and adolescents can result from a diverse array of disorders namely; metabolic, endocrine, neoplastic, infectious, immunologic, and genetic skeletal dysplasias.
- Osteogenesis imperfecta
- Primary hyperparathyroidism
- Simple bone cyst
- Aneurismal bone cyst
- Disuse osteoporosis
- Chronic osteomyelitis
- Osteogenesis imperfecta
- Rickets
- Renal osteodystrophy
- Malignant infantile osteopetrosis
- juvenile osteoporosis
- juvenile rheumatoid arthritis
Osteoporosis is due to causal factors like atrophy of disuse and gonadal deficiency. Hence osteoporosis is common in post menopausal women and in men above 50 yrs. Hypercorticism may also be causal factor, as osteoporosis may be seen as a feature of Cushing's syndrome.
Studies of the benefits of supplementation with calcium and vitamin D are conflicting, possibly because most studies did not have people with low dietary intakes. A 2013 review by the USPSTF found insufficient evidence to determine if supplementation with calcium and vitamin D results in greater harm or benefit in men and premenopausal women. The USPSTF did not recommend low dose supplementation (less than 1 g of calcium and 400 IU of vitamin D) in postmenopausal women as there does not appear to be a difference in fracture risk. It is unknown what effect higher doses have. A 2015 review found little data that supplementation of calcium decreases the risk of fractures.
While some meta-analyses have found a benefit of vitamin D supplements combined with calcium for fractures, they did not find a benefit of vitamin D supplements alone.
While supplementation does not appear to affect the risk of death, there is an increased risk of myocardial infarctions with calcium supplementation, kidney stones, and stomach problems.
Vitamin K deficiency is also a risk factor for osteoporotic fractures. The gene gamma-glutamyl carboxylase (GGCX) is dependent on vitamin K. Functional polymorphisms in the gene could attribute to variation in bone metabolism and BMD. Vitamin K2 is also used as a means of treatment for osteoporosis and the polymorphisms of GGCX could explain the individual variation in the response to treatment of vitamin K. Vitamin K supplementation may reduce the risk of fractures in postmenopausal women; however, there is no evidence for men.
Fibrous dysplasia is a disorder where normal bone and marrow is replaced with fibrous tissue, resulting in formation of bone that is weak and prone to expansion. As a result, most complications result from fracture, deformity, functional impairment, and pain. Disease occurs along a broad clinical spectrum ranging from asymptomatic, incidental lesions to severe disabling disease. Disease can affect one bone (monostotic) or multiple (polyostotic), and may occur in isolation or in combination with cafe-au-lait skin macules and hyperfunctioning endocrinopathies, termed McCune-Albright syndrome. More rarely, fibrous dysplasia may be associated with intramuscular myxomas, termed Mazabraud's syndrome. Fibrous dysplasia is very rare, and there is no known cure. Fibrous dysplasia is not a form of cancer.
Recovery from renal osteodystrophy has been observed following kidney transplantation. Renal osteodystrophy is a chronic condition with a conventional hemodialysis schedule. Nevertheless, it is important to consider that the broader concept of CKD-MBD, which includes renal osteodystrophy, is not only associated with bone disease and increased risk of fractures but also with cardiovascular calcification, poor quality of life and increased morbidity and mortality in CKD patients (the so-called bone-vascular axis). Actually, bone may now be considered a new endocrine organ at the heart of CKD-MBD.
Clinical trials of isotretinoin, etidronate with oral corticosteroids, and perhexiline maleate have failed to demonstrate effectiveness, though the variable course of the disease and small prevalence induces uncertainty.
A handful of pharmaceutical companies focused on rare disease are currently in varying stages of investigation into different therapeutic approaches for FOP.
In August 2015, U.S. Food and Drug Administration (FDA) Office of Orphan Products Development granted La Jolla Pharmaceuticals orphan drug designation for two novel compounds for FOP. The compounds are small-molecule kinase inhibitors designed to selectively block ACVR1 (ALK2).
In August 2015, Clementia Pharmaceuticals also began the enrollment of children (ages 6 and above) into its Phase II clinical trial investigating palovarotene for the treatment of FOP. Preclinical studies demonstrated that palovarotene, a retinoic acid receptor gamma agonist, blocked abnormal bone formation in animal models via inhibition of secondary messenger systems in the BMP pathway. Clementia licensed palovarotene from Roche Pharmaceuticals, which previously evaluated the compound in more than 800 individuals including healthy volunteers and patients with chronic obstructive pulmonary disease. Palovarotene received Fast Track designation from the U.S. Food and Drug Administration (FDA) and orphan designations for the treatment of FOP from both the FDA and the European Medicines Agency (EMA).
In September 2015, Regeneron announced new insight into the mechanism of disease involving the activation of the ACVR1 receptor by activin A. In 2016, the company initiated a phase 1 study of its activin antibody, REGN 2477, in healthy volunteers; a phase 2 trial in FOP patients is planned for 2017.
Another potential therapeutic approach involves allele-specific RNA interference that targets mutated mRNA for degradation while preserving normal ACVR1 gene expression.
Further investigation into the mechanisms of heterotopic bone formation in FOP could aid in the development of treatments for other disorders involving extra-skeletal bone formation.
Treatment for renal osteodystrophy includes the following:
- calcium and/or native vitamin D supplementation
- restriction of dietary phosphate (especially inorganic phosphate contained in additives)
- phosphate binders such as calcium carbonate, calcium acetate, sevelamer hydrochloride or carbonate, lanthanum carbonate, sucroferric oxyhydroxide, ferric citrate among others
- active forms of vitamin D (calcitriol, alfacalcidol, paricalcitol, maxacalcitol, doxercalciferol, among others)
- cinacalcet
- renal transplantation
- haemodialysis five times a week is thought to be of benefit
- parathyroidectomy for symptomatic medication refractive end stage disease
X-linked hypophosphatemia (XLH), also called X-linked dominant hypophosphatemic rickets, X-linked vitamin d-resistant rickets, is an X-linked dominant form of rickets (or osteomalacia) that differs from most cases of rickets in that ingestion of vitamin D is relatively ineffective. It can cause bone deformity including short stature and genu varum (bow leggedness). It is associated with a mutation in the PHEX gene sequence (Xp.22) and subsequent inactivity of the PHEX protein. The prevalence of the disease is 1:20000. The leg deformity can be treated with Ilizarov frames and CAOS surgery.
Metabolic bone disease is an umbrella term referring to abnormalities of bones caused by a broad spectrum of disorders.
Most commonly these disorders are caused by abnormalities of minerals such as calcium, phosphorus, magnesium or vitamin D leading to dramatic clinical disorders that are commonly reversible once the underlying defect has been treated. These disorders are to be differentiated from a larger group of genetic bone disorders where there is a defect in a specific signaling system or cell type that causes the bone disorder. There may be overlap. For example, genetic or hereditary hypophosphatemia may cause the metabolic bone disorder osteomalacia. Although there is currently no treatment for the genetic condition, replacement of phosphate often corrects or improves the metabolic bone disorder.
Perinatal and infantile hypophosphatasia are inherited as autosomal recessive traits with homozygosity or compound heterozygosity for two defective TNSALP alleles. The mode of inheritance for childhood, adult, and odonto forms of hypophosphatasia can be either autosomal dominant or recessive. Autosomal transmission accounts for the fact that the disease affects males and females with equal frequency. Genetic counseling is complicated by the disease’s variable inheritance pattern, and by incomplete penetration of the trait.
Hypophosphatasia is a rare disease that has been reported worldwide and appears to affect individuals of all ethnicities. The prevalence of severe hypophosphatasia is estimated to be 1:100,000 in a population of largely Anglo-Saxon origin. The frequency of mild hypophosphatasia is more challenging to assess because the symptoms may escape notice or be misdiagnosed. The highest incidence of hypophosphatasia has been reported in the Mennonite population in Manitoba, Canada where one in every 25 individuals are considered carriers and one in every 2,500 newborns exhibits severe disease. Hypophosphatasia is considered particularly rare in people of African ancestry in the U.S.
There is no cure or approved treatment for FOP. Attempts to surgically remove the bone result in explosive bone growth. While under anesthesia, people with FOP may encounter difficulties with intubation, restrictive pulmonary disease, and changes in the electrical conduction system of the heart. Activities that increase the risk of falling or soft tissue injury should be avoided, as even minor trauma may provoke heterotopic bone formation.
An endocrine bone disease is a bone disease associated with a disorder of the endocrine system. An example is osteitis fibrosa cystica.
Axial osteomalacia is a rare osteosclerotic disorder characterized by axial skeleton pain, coarsening of the trabecular bone pattern on radiographs of the axial but not appendicular skeleton.