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Many types of dwarfism are currently impossible to prevent because they are genetically caused. Genetic conditions that cause dwarfism may be identified with genetic testing, by screening for the specific variations that result in the condition. However, due to the number of causes of dwarfism, it may be impossible to determine definitively if a child will be born with dwarfism.
Dwarfism resulting from malnutrition or a hormonal abnormality may be treated with an appropriate diet or hormonal therapy. Growth hormone deficiency may be remedied via injections of human growth hormone (HGH) during early life.
Gene based therapy is being studied. In June 2015, BioMarin announced positive results of their Phase 2 study, stating that 10 children experienced a mean increase of 50% in their annualized growth velocity.
Genetic mutations of most forms of dwarfism caused by bone dysplasia cannot be altered yet, so therapeutic interventions are typically aimed at preventing or reducing pain or physical disability, increasing adult height, or mitigating psychosocial stresses and enhancing social adaptation.
Forms of dwarfism associated with the endocrine system may be treated using hormonal therapy. If the cause is prepubescent hyposecretion of growth hormone, supplemental growth hormone may correct the abnormality. If the receptor for growth hormone is itself affected, the condition may prove harder to treat. Hypothyroidism is another possible cause of dwarfism that can be treated through hormonal therapy. Injections of thyroid hormone can mitigate the effects of the condition, but lack of proportion may be permanent.
Pain and disability may be ameliorated by physical therapy, braces or other orthotic devices, or by surgical procedures. The only simple interventions that increase perceived adult height are dress enhancements, such as shoe lifts or hairstyle. Growth hormone is rarely used for shortness caused by bone dysplasias, since the height benefit is typically small (less than ) and the cost high. The most effective means of increasing adult height by several inches is distraction osteogenesis, though availability is limited and the cost is high in terms of money, discomfort, and disruption of life. Most people with dwarfism do not choose this option, and it remains controversial. For other types of dwarfism, surgical treatment is not possible.
Achondroplasia is one of 19 congenital conditions with similar presentations, such as osteogenesis imperfecta, multiple epiphyseal dysplasia tarda, achondrogenesis, osteopetrosis, and thanatophoric dysplasia. This makes estimates of prevalence difficult, with changing and subjective diagnostic criteria over time. One detailed and long-running study in the Netherlands found that the prevalence determined at birth was only 1.3 per 100,000 live births. Another study at the same time found a rate of 1 per 10,000.
Life expectancy for individuals with hypochondroplasia is normal; the maximum height is about 147 cm or 4.8 ft.
There are as yet no effective treatments for primordial dwarfism. It is known that PD is caused by inheriting a mutant gene from each parent. The lack of normal growth in the disorder is not due to a deficiency of growth hormone, as in hypopituitary dwarfism. Administering growth hormone, therefore, has little or no effect on the growth of the individual with primordial dwarfism, except in the case of Russell Silver Syndrome. Individuals with RSS respond favorably to growth hormone treatment, this fact is supported by The Magic Foundation. Children with RSS that are treated with growth hormone before puberty may achieve several inches of additional height. In January 2008, it was published that mutations in the pericentrin gene (PCNT) were found to cause primordial dwarfism. Pericentrin has a role in cell division, proper chromosome segregation, and cytokinesis.
There is no treatment at this time to promote bone growth in chondrodystrophy patients. Certain types of growth hormone seem to increase the rate of growth during the first year of life/treatment, but have no substantial effect in adult patients. Only a few surgical centers in the world perform, experimentally, leg and arm lengthening procedures. Most common therapies are found in seeking help from: family physicians, pediatrics, internists, endocrinologists, geneticists, orthopedists and neurologists.
A recent article in 2015 reported a persistent notochord in a fetus at 23 weeks of gestation. The fetus had an abnormal spine, shortened long bones and a left clubfoot. After running postmortem tests and ultrasound, the researchers believed that the fetus suffered from hypochondrogenesis. Hypochondrogenesis is caused when type II collagen is abnormally formed due to a mutation in the COL2A1 gene. Normally, the cartilaginous notochord develops into the bony vertebrae in a human body. The COL2A1 gene results in malformed type II collagen, which is essential in the transition from collagen to bone. This is the first time that researchers found a persistent notochord in a human body due to a COL2A1 mutation.
Chondrodystrophy (literally, "cartilage maldevelopment") refers to a skeletal disorder caused by one of myriad genetic mutations that can affect the development of cartilage. As a very general term it is only used in the medical literature when a more precise description of the condition is unavailable.
Like treatment options, the prognosis is dependent on the severity of the symptoms. Despite the various symptoms and limitations, most individuals have normal intelligence and can lead a normal life.
In regards to treatment of hypochondroplasia usually takes the form of orthopedic surgery and physical therapy. Genetic counseling is advised for individuals and their families. Specifically in the case of spinal stenosis, one option is laminectomy.
The term thanatophoric is Greek for "death bearing". Children with this condition are usually stillborn or die shortly after birth from respiratory failure, however a small number of individuals have survived into childhood and a very few beyond. Survivors have difficulty breathing on their own and require respiratory support such as high flow oxygen through a canula or ventilator support via tracheostomy. There may also be evidence of spinal stenosis and seizures.
The oldest known living TD survivor is a 29-year-old female. One male lived to be 26 years old. Another male lived to age 20. TD survivor, Chrisopher Álvarez, 18, is Colombian living in New York. Two children with TD aged 10 and 12, a male and a female, are known in Germany. There is also a 6-year-old male living with TD and two 1-year old males.
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.
Primordial dwarfism is a form of dwarfism that results in a smaller body size in all stages of life beginning from before birth. More specifically, primordial dwarfism is a diagnostic category including specific types of profoundly proportionate dwarfism, in which individuals are extremely small for their age, even as a fetus. Most individuals with primordial dwarfism are not diagnosed until they are about 3-5 years of age.
Medical professionals typically diagnose the fetus as being small for the gestational age, or as having intrauterine growth disability when an ultrasound is conducted. Typically, people with primordial dwarfism are born with very low birth weights. After birth, growth continues at a much slower rate, leaving individuals with primordial dwarfism perpetually years behind their peers in stature and in weight.
Most cases of short stature are caused by skeletal or endocrine disorders. The five subtypes of primordial dwarfism are among the most severe forms of the 200 types of dwarfism, and some sources estimate that there are only 100 individuals in the world with the disorder. Other sources list the number of people
currently afflicted as high as 100 in North America.
It is rare for individuals affected by primordial dwarfism to live past the age of 30. In the case of microcephalic osteodysplastic primordial dwarfism type 2 (MOPDII) there can be increased risk of vascular problems, which may cause premature death.
The fibrocartilaginous effects of fibrochondrogenesis on chondrocytes has shown potential as a means to produce therapeutic cellular biomaterials via tissue engineering and manipulation of stem cells, specifically human embryonic stem cells.
Utilization of these cells as curative cartilage replacement materials on the cellular level has shown promise, with beneficial applications including the repair and healing of damaged knee menisci and synovial joints; temporomandibular joints, and vertebra.
Thanatophoric dysplasia (thanatophoric dwarfism) is a severe skeletal disorder characterized by a disproportionately small ribcage, extremely short limbs and folds of extra skin on the arms and legs.
People with Laron syndrome have strikingly low rates of cancer and diabetes, although they appear to be at increased risk of accidental death due to their stature.
Osteogenesis imperfecta is a rare condition in which bones break easily. There are multiple genetic mutations in different genes for collagen that may result in this condition. It can be treated with some drugs to promote bone growth, by surgically implanting metal rods in long bones to strengthen them, and through physical therapy and medical devices to improve mobility.
Children with PSS have extremely low levels of growth hormone. These children possibly have a problem with growth hormone inhibiting hormone (GHIH) or growth hormone releasing hormone (GHRH). The children could either be unresponsive to GHRH, or too sensitive to GHIH.
Children who have PSS exhibit signs of failure to thrive. Even though they appear to be receiving adequate nutrition, they do not grow and develop normally compared to other children of their age.
An environment of constant and extreme stress causes PSS. Stress releases hormones in the body such as epinephrine and norepinephrine engage what is known as the 'fight or flight' response. The heart speeds up and the body diverts resources away from processes that are not immediately important; in PSS, the production of growth hormone (GH) is thus affected. As well as lacking growth hormone, children with PSS exhibit gastrointestinal problems due to the large amounts of epinephrine and norepinephrine, resulting in their bodies lacking proper digestion of nutrients and further affecting development.
While the cure for PSS is questionable, some studies show that placing the child affected with the disease in a foster or group home increases growth rate and socialization skills.
Spondyloepiphyseal dysplasia congenita (abbreviated to SED more often than SDC) is a rare disorder of bone growth that results in dwarfism, characteristic skeletal abnormalities, and occasionally problems with vision and hearing. The name of the condition indicates that it affects the bones of the spine (spondylo-) and the ends of bones (epiphyses), and that it is present from birth (congenital). The signs and symptoms of spondyloepiphyseal dysplasia congenita are similar to, but milder than, the related skeletal disorders achondrogenesis type 2 and hypochondrogenesis. Spondyloepiphyseal dysplasia congenita is a subtype of collagenopathy, types II and XI.
Fibrochondrogenesis is quite rare. A 1996 study from Spain determined a national minimal prevalence for the disorder at 8 cases out of 1,158,067 live births.
A United Arab Emirates (UAE) University report, from early 2003, evaluated the results of a 5-year study on the occurrence of a broad range of osteochondrodysplasias. Out of 38,048 newborns in Al Ain, over the course of the study period, fibrochondrogenesis was found to be the most common of the recessive forms of osteochondrodysplasia, with a prevalence ratio of 1.05:10,000 births.
While these results represented the most common occurrence within the group studied, they do not dispute the rarity of fibrochondrogenesis. The study also included the high rate of consanguinous marriages as a prevailing factor for these disorders, as well as the extremely low rate of diagnosis-related pregnancy terminations throughout the region.
Early journal reports of boomerang dysplasia suggested X-linked recessive inheritance, based on observation and family history. It was later discovered, however, that the disorder is actually caused by a genetic mutation fitting an autosomal dominant genetic profile.
Autosomal dominant inheritance indicates that the defective gene responsible for a disorder is located on an autosome, and only one copy of the gene is sufficient to cause the disorder, when inherited from a parent who has the disorder.
Boomerang dysplasia, although an autosomal dominant disorder, is "not" inherited because those afflicted do not live beyond infancy. They cannot pass the gene to the next generation.
There is no causative / curative therapy. Symptomatic medical treatments are focussing on symptoms caused by orthopaedic, dental or cardiac problems. Regarding perioperative / anesthesiological management, recommendations for medical professionals are published at OrphanAnesthesia.
Lenz–Majewski syndrome is a skin condition characterized by hyperostosis, craniodiaphyseal dysplasia, dwarfism, cutis laxa, proximal symphalangism, syndactyly, brachydactyly, mental retardation, enamel hypoplasia, and hypertelorism.
In 2013, whole-exome sequencing showed that a missense mutation resulting in overactive phosphatidylserine synthase 1 was the cause of LMS, making it the first known human disease to be caused by disrupted phosphatidylserine metabolism. The researchers suggested a link between the condition and bone metabolism.
Acromicric dysplasia is an extremely rare inherited disorder characterized by abnormally short hands and feet, growth retardation and delayed bone maturation leading to short stature. Most cases have occurred randomly for no apparent reason (sporadically). However, autosomal dominant inheritance has not been ruled out.
According to the disease database, Acromicric dysplasia is synonymous with Geleophysic dysplasia
(or Geleophysic Dwarfism) and Focal mucopolysaccharidosis.