Acrodysostosis

Acrodysostosis is a rare congenital malformation syndrome which involves shortening of the interphalangeal joints of the hands and feet, intellectual disability in approximately 90% of affected children, and peculiar facies. Other common abnormalities include short head (as measured front to back), small broad upturned nose with flat nasal bridge, protruding jaw, increased bone age, intrauterine growth retardation, juvenile arthritis and short stature. Further abnormalities of the skin, genitals, teeth, and skeleton may occur.

Cause

Most reported cases have been sporadic, but it has been suggested that the condition might be genetically related i.e. in an autosomal dominant mode of transmission. Both males and females are affected. The disorder has been associated with the older age of parents at the time of conception.

A PRKAR1A mutation has been identified in acrodysostosis with hormone resistance.

Symptoms

Symptoms of this disorder include:

• Frequent middle ear infections
• Growth problems, short arms and legs
• Hearing problems
• Intellectual disability
• The body doesn't respond to certain hormones, even though hormone levels are normal
• Distinct facial features

Diagnosis

The health care provider can usually diagnose this condition with a physical exam. This may show any of the following:

• Advanced bone age
• Bone deformities in hands and feet
• Delays in growth
• Problems with the skin, genitals, teeth, and skeleton
• Short arms and legs with small hands and feet
• Short head, measured front to back
• Short height
• Small, upturned broad nose with flat bridge
• Distinct features of the face (short nose, open mouth, jaw that sticks out)
• Unusual head
• Wide-spaced eyes, sometimes with extra skin fold at corner of eye

In the first months of life, x-rays may show spotty calcium deposits, called stippling, in bones (especially the nose). Infants may also have:

• Abnormally short fingers and toes
• Early growth of bones in the hands and feet
• Short bones
• Shortening of the forearm bones near the wrist
• Two genes have been linked with this condition, and genetic testing may be done.

Treatment

• Treatment depends on the symptoms.
• Hormones, such as growth hormone, may be given.
• Surgery to treat bone problems may be done.

Epidemiology

This disorder is present at birth, however, it may not be understood until several years after birth. Acrodysostosis affects males and females in almost similar numbers. It is difficult to determine the frequency of acrodysostosis in the population as many cases of this disorder cannot be diagnosed properly.

Further reading

• "Acrodysostosis: Disease Information from NORD". National Organization for Rare Disorders.

• Acrodysostosis at NIH's Office of Rare Diseases

External links

Classification	ICD-10: Q75.4 OMIM: 101800 MeSH: C538179 DiseasesDB: 31405
External resources	MedlinePlus: 001248 Orphanet: 950