Axial spondylometaphyseal dysplasia
Prevalence estimates on Rare Medical Network websites are calculated based on data available from numerous sources, including US and European government statistics, the NIH, Orphanet, and published epidemiologic studies. Rare disease population data is recognized to be highly variable, and based on a wide variety of source data and methodologies, so the prevalence data on this site should be assumed to be estimated and cannot be considered to be absolutely correct.
Age of Onset
Autosomal dominant ?A pathogenic variant in only one gene copy in each cell is sufficient to cause an autosomal dominant disease
Autosomal recessive ?Pathogenic variants in both copies of each gene of the chromosome are needed to cause an autosomal recessive disease and observe the mutant phenotype
X-linked dominant ?X-linked dominant inheritance, sometimes referred to as X-linked dominance, is a mode of genetic inheritance by which a dominant gene is carried on the X chromosome.
X-linked recessive ?Pathogenic variants in both copies of a gene on the X chromosome cause an X-linked recessive disorder
Mitochondrial or multigenic ?Mitochondrial genetic disorders can be caused by changes (mutations) in either the mitochondrial DNA or nuclear DNA that lead to dysfunction of the mitochondria and inadequate production of energy.
Multigenic or multifactor ?Inheritance involving many factors, of which at least one is genetic but none is of overwhelming importance, as in the causation of a disease by multiple genetic and environmental factors.
Other Names (AKA)
Axial SMD; Spondylometaphyseal dysplasia axial type; SMD Axial
Congenital and Genetic Diseases; Musculoskeletal Diseases
Axial spondylometaphyseal dysplasia is a genetic disorder of bone growth. The term “axial” means towards the center of the body. “Sphondylos” is a Greek term meaning vertebra. “Metaphyseal dysplasia” refers to abnormalities at the ends of long bones. Axial spondylometaphyseal dysplasia primarily affects the bones of the chest, pelvis, spine, upper arms and upper legs, and results in shortened stature. For reasons not well understood, this rare skeletal dysplasia is also associated with early and progressive vision loss. The underlying genetic cause of axial spondylometaphyseal dysplasia is currently unknown. It is thought to be
Common signs and sympotms of axial spondylometaphyseal dysplasia, include
People with axial spondylometaphyseal dysplasia may have a normal birth length, but demonstrate growth failure by late infancy to early childhood. A measurement called standard deviation (SD) is used to compare the height of different children. If a child's height is more than 2 SD's below the average height of other children the same age, the child is said to have short stature. This means that almost all of the other children that age (more than 95% or 19 out of 20) are taller. Individual case reports of children and an adult with axial spondlometaphyseal dysplasia demonstrate height as being between 2 to 6 SD’s below average.
Infants with axial spondlometaphyseal dysplasia tend to have a shortened chest with short ribs, a condition called thoracic hypoplasia. Thoracic hypoplasia tends to become more prominent in childhood, and less noticeable in adolescence and adulthood. Thoracic hypoplasia may cause mild to moderate breathing problems in infants and recurring lung infections in childhood.
Young children with axial spondlometaphyseal dysplasia have shortened upper arms and upper leg bones, which may become less prominent as they grow.
Spine changes include vertebrae that have a flattened appearance on
Pelvic bone changes can be seen in infants and children. Some of these changes self-correct by adulthood. A condition called “coxa vara” (where the angle between the top of the femur and the femoral shaft is smaller than normal) is common beginning in late childhood and persists through adulthood. Coxa vara may affect gait (pattern or way of walking). Some people with axial spondlometaphyseal dysplasia have minor bone changes in their knees.
Vision problems, including retinitis pigmentosa and/or optic atrophy, become evident in infancy or early childhood and rapidly worsen. Retinitis pigmentosa causes
This table lists symptoms that people with this disease may have. For most diseases, symptoms will vary from person to person. People with the same disease may not have all the symptoms listed. This information comes from a database called the Human Phenotype Ontology (HPO) . The HPO collects information on symptoms that have been described in medical resources. The HPO is updated regularly. Use the HPO ID to access more in-depth information about a symptom.
|Medical Terms||Other Names||
|80%-99% of people have these symptoms|
|Delayed skeletal maturation||
Delayed bone maturation
Delayed skeletal development
[ more ]
Disproportionately short upper portion of limb
Loss of eyesight
[ more ]
|30%-79% of people have these symptoms|
|Irregular iliac crest||0003796|
|Proximal femoral metaphyseal irregularity||0003411|
[ more ]
|5%-29% of people have these symptoms|
Nasal tip, upturned
Upturned nasal tip
[ more ]
Abnormal curving of the cornea or lens of the eye
|Downslanted palpebral fissures||
Downward slanting of the opening between the eyelids
Widely spaced eyes
[ more ]
Extreme sensitivity of the eyes to light
[ more ]
Eyeballs bulging out
[ more ]
Decreased length of nose
[ more ]
Corners of eye widely separated
|1%-4% of people have these symptoms|
Increased spleen size
|Percent of people who have these symptoms is not available through HPO|
|Anterior rib cupping||0000907|
|Narrow greater sciatic notch||0003375|
Involuntary, rapid, rhythmic eye movements
|Reduced sperm motility||0012207|
|Short femoral neck||
Short neck of thighbone
Decreased body height
[ more ]
The Little People of America, Inc Web site lists articles on repiratory and breathing problems in people with skeletal dysplasias, including an article titled Breathing Problems Among Little People: When to Be Concerned.
Detailed information related to the management of coxa vara can also be found in the Treatment sections of a Medscape Reference review article on this condition.
Johns Hopkins Department of Orthopedic Surgery offers a Patient Guide to Scoliosis.
MedlinePlus.gov provides information on optic atrophy.
Further medical support resources can be found through the Little People of America, Inc.
These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.
- The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
- Online Mendelian Inheritance in Man (OMIM) is a catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine.
- Orphanet is a European reference portal for information on rare diseases and orphan drugs. Access to this database is free of charge.
- PubMed is a searchable database of medical literature and lists journal articles that discuss Axial spondylometaphyseal dysplasia. Click on the link to view a sample search on this topic.
- Suzuki S, Kim OH, Makita Y, Saito T, Lim GY, Cho TJ, Al-Swaid A, Alrasheed S, Sadoon E, Miyazaki O, Nishina S, Superti-Furga A, Unger S, Fujieda K, Ikegawa S, Nishimura G. Axial spondylometaphyseal dysplasia: additional reports. Am J Med Genet A. 2011 Oct;155A(10):2521-8. Epub 2011 Sep 9; https://www.ncbi.nlm.nih.gov/pubmed/21910225. Accessed 9/14/2012.
- Short Stature. MedlinePlus. https://www.nlm.nih.gov/medlineplus/ency/article/003271.htm. Accessed 9/14/2012.