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Management of rhizomelic chondrodysplasia punctate can include physical therapy, additionally orthopedic procedures improved function sometimes in affected people. However the prognosis is poor in this condition.
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.
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.
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.
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.
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.
Since primordial dwarfism disorders are extremely rare, misdiagnosis is common. Because children with PD do not grow like other children, poor nutrition, a metabolic disorder, or a digestive disorder may be diagnosed initially. The correct diagnosis of PD may not be made until the child is 5 years old and it becomes apparent that the child has severe dwarfism.
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.
Alopecia contractures dwarfism mental retardation syndrome or (ACD mental retardation syndrome) is a developmental disorder which causes mainly baldness and dwarfism in combination with intellectual disability; skeletal anomalies, caries and nearsightedness are also typical.
The ACD mental retardation syndrome was first described in 1980 by Albert Schinzel and only few cases have since been identified in the world. At the time Dr. Schinzel made no conclusion of the hereditary pattern of this syndrome but similarities between cases reported by year 2000 seem to suggest autosomal or x-linked recessive inheritance or possibly a dominant mutation caused by mosaicism as causes of this syndrome.
The disorder was first described in 1969 by the German-American Human Geneticist Meinhard Robinow (1909–1997), along with physicians Frederic N. Silverman and Hugo D. Smith, in the "American Journal of Diseases of Children". By 2002, over 100 cases had been documented and introduced into medical literature.
Majewski's polydactyly syndrome, also known as polydactyly with neonatal chondrodystrophy type I, short rib-polydactyly syndrome type II, and short rib-polydactyly syndrome, is a lethal form of neonatal dwarfism characterized by osteochondrodysplasia (skeletal abnormalities in the development of bone and cartilage) with a narrow thorax, polysyndactyly, disproportionately short tibiae, thorax dysplasia, hypoplastic lungs and respiratory insufficiency. Associated anomalies include protruding abdomen, brachydactyly, peculiar faces, hypoplastic epiglottis, cardiovascular defects, renal cysts, and also genital anomalies. Death occurs before or at birth.
The disease is inherited in an autosomal recessive pattern.
It was characterized in 1971.
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.
There is no medical treatment for either syndrome but there are some recommendations that can help with prevention or early identification of some of the problems. Children with either syndrome should have their hearing tested, and adults should be aware that the hearing loss may not develop until the adult years. Yearly visits to an ophthalmologist or other eye care professional who has been informed of the diagnosis of Stickler or Marshall syndrome is important for all affected individuals. Children should have the opportunity to have myopia corrected as early as possible, and treatment for cataracts or detached retinas may be more effective with early identification. Support for the joints is especially important during sports, and some recommend that contact sports should be avoided by those who have very loose joints.
The Seckel syndrome or microcephalic primordial dwarfism (also known as bird-headed dwarfism, Harper's syndrome, Virchow-Seckel dwarfism, and Bird-headed dwarf of Seckel) is an extremely rare congenital nanosomic disorder.
Inheritance is autosomal recessive.
It is characterized by intrauterine growth retardation and postnatal dwarfism with a small head, narrow bird-like face with a beak-like nose, large eyes with down-slanting palpebral fissures , receding mandible and intellectual disability.
A mouse model has been developed. This mouse model is characterized by a severe deficiency of ATR protein. These mice suffer high levels of replicative stress and DNA damage. Adult Seckel mice display accelerated aging. These findings are consistent with the DNA damage theory of aging.
Rhizomelic chondrodysplasia punctata is a rare, developmental brain disorder characterized by systemic shortening of the proximal bones (i.e. rhizomelia), seizures, recurrent respiratory tract infections, and congenital cataracts. The affected individuals have low levels of plasmalogens.
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.
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.
While there is no cure for JBS, treatment and management of specific symptoms and features of the disorder are applied and can often be successful. Variability in the severity of JBS on a case-by-case basis determines the requirements and effectiveness of any treatment selected.
Pancreatic insufficiency and malabsorption can be managed with pancreatic enzyme replacement therapy, such as pancrelipase supplementation and other related methods.
Craniofacial and skeletal deformities may require surgical correction, using techniques including bone grafts and osteotomy procedures. Sensorineural hearing loss can be managed with the use of hearing aids and educational services designated for the hearing impaired.
Special education, specialized counseling methods and occupational therapy designed for those with mental retardation have proven to be effective, for both the patient and their families. This, too, is carefully considered for JBS patients.
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.
Cartilage–hair hypoplasia (CHH), also known as McKusick type metaphyseal chondrodysplasia, is a rare genetic disorder. It is a highly pleiotropic disorder that clinically manifests by form of short-limbed dwarfism due to skeletal dysplasia, variable level of immunodeficiency and predisposition to malignancies in some cases. It was first reported in 1965 by McKusick et al. Actor Verne Troyer is affected with this form of dwarfism, as was actor Billy Barty, who was renowned for saying "The name of my condition is Cartilage Hair Syndrome Hypoplasia, but you can just call me Billy."
Patients with CHH usually suffer from cellular immunodeficiency. In the study of 108 Finnish patients with CHH there was detected mild to moderate form of lymphopenia, decreased delayed type of hypersensitivity and impaired responses to phytohaemagglutinin. This leads to susceptibility to and, in some more severe cases, mortality from infections early in childhood. There has also been detected combined immunodeficiency in some patients
Patients with CHH often have increased predispositions to malignancies.
The caloric intake of children with SRS must be carefully controlled in order to provide the best opportunity for growth. If the child is unable to tolerate oral feeding, then enteral feeding may be used, such as the percutaneous endoscopic gastrostomy.
In children with limb-length differences or scoliosis, physiotherapy can alleviate the problems caused by these symptoms. In more severe cases, surgery to lengthen limbs may be required. To prevent aggravating posture difficulties children with leg length differences may require a raise in their shoe.
Growth hormone therapy is often prescribed as part of the treatment of SRS. The hormones are given by injection typically daily from the age of 2 years old through teenage years. It may be effective even when the patient does not have a growth hormone deficiency. Growth hormone therapy has been shown to increase the rate of growth in patients and consequently prompts 'catch up' growth. This may enable the child to begin their education at a normal height, improving their self-esteem and interaction with other children. The effect of growth hormone therapy on mature and final height is as yet uncertain. There are some theories suggesting that the therapy also assists with muscular development and managing hypoglycemia.
Treatment for MSS is symptomatic and supportive including physical and occupational therapy, speech therapy, and special education. Cataracts must be removed when vision is impaired, generally in the first decade of life. Hormone replacement therapy is needed if hypogonadism is present.
Mesomelia refers to conditions in which the middle parts of limbs are disproportionately short. When applied to skeletal dysplasias, mesomelic dwarfism describes generalised shortening of the forearms and lower legs. This is in contrast to rhizomelic dwarfism in which the upper portions of limbs are short such as in achondroplasia.
Forms of mesomelic dwarfism currently described include:
- Langer mesomelic dysplasia
- Ellis–van Creveld syndrome
- Robinow syndrome
- Léri–Weill dyschondrosteosis
Medical conditions include frequent ear infection, hearing loss, hypotonia, developmental problems, respiratory problems, eating difficulties, light sensitivity, and esophageal reflux.
Data on fertility and the development of secondary sex characteristics is relatively sparse. It has been reported that both male and female patients have had children. Males who have reproduced have all had the autosomal dominant form of the disorder; the fertility of those with the recessive variant is unknown.
Researchers have also reported abnormalities in the renal tract of affected patients. Hydronephrosis is a relatively common condition, and researchers have theorized that this may lead to urinary tract infections. In addition, a number of patients have suffered from cystic dysplasia of the kidney.
A number of other conditions are often associated with Robinow syndrome. About 15% of reported patients suffer from congenital heart defects. Though there is no clear pattern, the most common conditions include pulmonary stenosis and atresia. In addition, though intelligence is generally normal, around 15% of patients show developmental delays.