Made by DATEXIS (Data Science and Text-based Information Systems) at Beuth University of Applied Sciences Berlin
Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
Oral phosphate, 9, calcitriol, 9; in the event of severe bowing, an osteotomy may be performed to correct the leg shape.
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.
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.
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.
Autosomal dominant hypophosphatemic rickets (ADHR) is a rare hereditary disease in which excessive loss of phosphate in the urine leads to poorly formed bones (rickets), bone pain, and tooth abscesses. ADHR is caused by a mutation in the fibroblast growth factor 23 (FGF23). ADHR affects men and women equally; symptoms may become apparent at any point from childhood through early adulthood. Blood tests reveal low levels of phosphate (hypophosphatemia) and inappropriately normal levels of vitamin D. Occasionally, hypophosphatemia may improve over time as urine losses of phosphate partially correct.
ADHR may be lumped in with X-linked hypophosphatemia under general terms such as "hypophosphatemic rickets". Hypophospatemic rickets are associated with at least nine other genetic mutations. Clinical management of hypophospatemic rickets may differ depending on the specific mutations associated with an individual case, but treatments are aimed at raising phosphate levels to promote normal bone formation.
Sufficient vitamin D levels can also be achieved through dietary supplementation and/or exposure to sunlight. Vitamin D (cholecalciferol) is the preferred form since it is more readily absorbed than vitamin D. Most dermatologists recommend vitamin D supplementation as an alternative to unprotected ultraviolet exposure due to the increased risk of skin cancer associated with sun exposure. Endogenous production with full body exposure to sunlight is approximately 250 µg (10,000 IU) per day.
According to the American Academy of Pediatrics (AAP), all infants, including those who are exclusively breast-fed, may need vitamin D supplementation until they start drinking at least of vitamin D-fortified milk or formula a day.
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.
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.
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
Treatment involves increasing dietary intake of calcium, phosphates and vitamin D. Exposure to ultraviolet B light (most easily obtained when the sun is highest in the sky), cod liver oil, halibut-liver oil, and viosterol are all sources of vitamin D.
A sufficient amount of ultraviolet B light in sunlight each day and adequate supplies of calcium and phosphorus in the diet can prevent rickets. Darker-skinned people need to be exposed longer to the ultraviolet rays. The replacement of vitamin D has been proven to correct rickets using these methods of ultraviolet light therapy and medicine.
Recommendations are for 400 international units (IU) of vitamin D a day for infants and children. Children who do not get adequate amounts of vitamin D are at increased risk of rickets. Vitamin D is essential for allowing the body to uptake calcium for use in proper bone calcification and maintenance.
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.
Standard intravenous preparations of potassium phosphate are available and are routinely used in malnourished patients and alcoholics. Oral supplementation is also useful where no intravenous treatment are available. Historically one of the first demonstrations of this was in concentration camp victims who died soon after being re-fed: it was observed that those given milk (high in phosphate) had a higher survival rate than those who did not get milk.
Monitoring parameters during correction with IV phosphate
- Phosphorus levels should be monitored after 2 to 4 hours after each dose, also monitor serum potassium, calcium and magnesium. Cardiac monitoring is also advised.
Schmid metaphyseal chondrodysplasia is a type of chondrodysplasia associated with a deficiency of collagen, type X, alpha 1.
Unlike other "rickets syndromes", affected individuals have normal serum calcium, phosphorus, and urinary amino acid levels. Long bones are short and curved, with widened growth plates and metaphyses.
It is named for the German researcher F. Schmid, who characterized it in 1949.
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 today, no agreed-upon treatment of Dent's disease is known and no therapy has been formally accepted. Most treatment measures are supportive in nature:
- Thiazide diuretics (i.e. hydrochlorothiazide) have been used with success in reducing the calcium output in urine, but they are also known to cause hypokalemia.
- In rats with diabetes insipidus, thiazide diuretics inhibit the NaCl cotransporter in the renal distal convoluted tubule, leading indirectly to less water and solutes being delivered to the distal tubule. The impairment of Na transport in the distal convoluted tubule induces natriuresis and water loss, while increasing the reabsorption of calcium in this segment in a manner unrelated to sodium transport.
- Amiloride also increases distal tubular calcium reabsorption and has been used as a therapy for idiopathic hypercalciuria.
- A combination of 25 mg of chlorthalidone plus 5 mg of amiloride daily led to a substantial reduction in urine calcium in Dent's patients, but urine pH was "significantly higher in patients with Dent’s disease than in those with idiopathic hypercalciuria (P < 0.03), and supersaturation for uric acid was consequently lower (P < 0.03)."
- For patients with osteomalacia, vitamin D or derivatives have been employed, apparently with success.
- Some lab tests on mice with CLC-5-related tubular damage showed a high-citrate diet preserved kidney function and delayed progress of kidney disease.
Treatment for secondary juvenile osteoporosis focuses on treating any underlying disorder.
Cystinosis is normally treated with cysteamine, which is available in capsules and in eye drops. People with cystinosis are also often given sodium citrate to treat the blood acidosis, as well as potassium and phosphorus supplements. If the kidneys become significantly impaired or fail, then treatment must be begun to ensure continued survival, up to and including renal transplantation.
Primary hypophosphatemia is the most common cause of nonnutritional rickets. Laboratory findings include low-normal serum calcium, moderately low serum phosphate, elevated serum alkaline phosphatase, and low serum 1,25 dihydroxy-vitamin D levels, hyperphosphaturia, and no evidence of hyperparathyroidism.
Other rarer causes include:
- Certain blood cancers such as lymphoma or leukemia
- Hereditary causes
- Liver failure
- Tumor-induced osteomalacia
Treatment of children with Fanconi syndrome mainly consists of replacement of substances lost in the urine (mainly fluid and bicarbonate).
Another approach would
Medical management of OFC consists of Vitamin D treatment, generally alfacalcidol or calcitriol, delivered intravenously. Studies have shown that in cases of OFC caused by either end-stage renal disease or primary hyperparathyoidism, this method is successful not only in treating underlying hyperparathyoidism, but also in causing the regression of brown tumors and other symptoms of OFC.
Treatment consists of oral bicarbonate supplementation. However, this will increase urinary bicarbonate wasting and may well promote a bicarbonate . The amount of bicarbonate given may have to be very large to stay ahead of the urinary losses. Correction with oral bicarbonate may exacerbate urinary potassium losses and precipitate hypokalemia. As with dRTA, reversal of the chronic acidosis should reverse bone demineralization.
Thiazide diuretics can also be used as treatment by making use of contraction alkalosis caused by them.
Abderhalden–Kaufmann–Lignac syndrome (AKL syndrome), also called Abderhalden–Lignac–Kaufmann disease or nephropathic cystinosis, is an autosomal recessive renal disorder of childhood comprising cystinosis and renal rickets.
It is named for Emil Abderhalden, Eduard Kaufmann and George Lignac.
In especially severe cases of OFC, parathyroidectomy, or the full removal of the parathyroid glands, is the chosen route of treatment. Parathyroidectomy has been shown to result in the reversal of bone resorption and the complete regression of brown tumors. In situations where parathyroid carcinoma is present, surgery to remove the tumors has also led to the regression of hyperparathyroidism as well as the symptoms of OFC.
Bone transplants have proven successful in filling the lesions caused by OFC. A report showed that in 8 out of 11 instances where cavities caused by OFC were filled with transplanted bone, the lesion healed and the transplanted bone blended rapidly and seamlessly with the original bone.
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.