What are the other names for this Condition? (Also known as/Synonyms)

• Acromesomelic Dwarfism

What is Acromesomelic Dysplasia? (Definition/Background Information)

• Acromesomelic Dysplasia is a skeletal disorder which is characterized by abnormally short forearms and forelegs (known as mesomelia), as well as short bones in the hands and feet (known as acromelia)
• There are 5 types of Acromesomelic Dysplasia:
  • Acromesomelic Dysplasia, Maroteaux type
  • Acromesomelic Dysplasia, Osebold-Remondini type
  • Acromesomelic Dysplasia with Genital Anomalies
  • Fibular Hypoplasia and Complex Brachydactyly (Du Pan Syndrome)
  • Grebe Dysplasia (including Hunter-Thompson type)
• Acromesomelic Dysplasia is an extremely rare and progressive disorder. The manifestations of this disorder can occur as early as the first few years of life
• Infants born with Acromesomelic Dysplasia have a normal birth weight. However, they may display short limbs as well as facial abnormalities
• Acromesomelic Dysplasia is an inherited condition with mutations in different chromosomes leading to the various types of the disorder (as stated above)
• Treatment of Acromesomelic Dysplasia focuses on the symptoms of the condition; it may include exercise, physical therapy, and surgery
• Despite the progressive nature of Acromesomelic Dysplasia, the affected individuals have regular intelligence levels and a normal life expectancy. However, over time, the limbs grow to be more disproportionate and an abnormal curvature of the spine may also develop

Who gets Acromesomelic Dysplasia? (Age and Sex Distribution)

• Acromesomelic Dysplasia is extremely rare; presently, there are less than 100 reported cases in the medical literature
• Acromesomelic Dysplasia may manifest itself as early as the neonatal phase (newborn stage)
• This condition may affect both males and females equally
• Individuals of all racial and ethnic groups may be affected

What are the Risk Factors for Acromesomelic Dysplasia? (Predisposing Factors)

The risk factors for Acromesomelic Dysplasia include:

• A family history of the condition 
• Being a child born to parents who are close blood relatives

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Acromesomelic Dysplasia? (Etiology)

Acromesomelic Dysplasia is inherited in an autosomal recessive manner. The various types of Acromesomelic Dysplasia is caused by mutations in genes on different chromosomes: 

• Acromesomelic Dysplasia, Maroteaux type - chromosome 9 at gene map locus 9p13-12
• Grebe Dysplasia (including Hunter-Thompson type) - chromosome 20 at gene map locus 20q11.2
• Fibular Hypoplasia and Complex Brachydactyly (Du Pan Syndrome) - chromosome 20 at gene map locus 20q11.2
• Acromesomelic Dysplasia with Genital Anomalies - chromosome 4 at locus q23-24
• Acromesomelic Dysplasia, Osebold-Remondini type: The exact genetic mutation is not known

Autosomal recessive mode of inheritance: Autosomal recessive conditions are traits or disorders that occur when two copies of an abnormal gene have been inherited on a non-sex chromosome. If both parents have an autosomal recessive condition, there is a 100% likelihood of passing on the mutated genes to their children. If, however, only one mutant copy of the gene is inherited, the individual will be a carrier of the condition, but will not be present with any symptoms. Children born to two carriers, have a 25% chance of being homozygous dominant (unaffected), a 50% chance of being heterozygous (carrier), and a 25% chance of being homozygous recessive (affected).

What are the Signs and Symptoms of Acromesomelic Dysplasia?

The signs and symptoms of Acromesomelic Dysplasia may include the following:

• Short stature
• Short limbs - forearms and forelegs
• Short hands and feet
• Broad hands and feet
• Spinal curvature
• Abnormal facial features that may include:
  • Enlarged head
  • Prominent forehead
  • Pronounced back of the head
  • Somewhat flattened mid-face
  • Abnormally small nose

How is Acromesomelic Dysplasia Diagnosed?

A diagnosis of Acromesomelic Dysplasia is made based on the information from the following:

• Complete physical evaluation
• An assessment of signs and symptoms
• Comprehensive analysis of family medical history
• Imaging tests, including specialized X-ray studies
• Differential diagnosis to rule out other disorders that may present similar signs and symptoms

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Acromesomelic Dysplasia?

The following complications may be observed for Acromesomelic Dysplasia:

• Extremely short stature
• Spinal curvature, leading to crowding of internal organs
• Low self-esteem
• Depression and anxiety

How is Acromesomelic Dysplasia Treated?

The treatment for Acromesomelic Dysplasia may include the following:

• Exercise and physical therapy to correct abnormal curvature of the spine
• Braces and casts to aid with the correction of bones
• Surgery to treat skeletal abnormalities
• Medication to treat associated depression and anxiety

How can Acromesomelic Dysplasia be Prevented?

Currently, Acromesomelic Dysplasia may not be preventable, since it is a genetic disorder.

• If there is a family history of the condition, then genetic counseling will help assess risks, before planning for a child
• Active research is currently being performed to explore the possibilities for treatment and prevention of inherited and acquired genetic disorders

Regular medical screening at periodic intervals with tests and physical examinations are recommended.

What is the Prognosis of Acromesomelic Dysplasia? (Outcomes/Resolutions)

• Due to the progressive nature of Acromesomelic Dysplasia, the signs and symptoms are likely to worsen over time. As a result, the limbs may develop disproportionately, leading to an abnormal curvature of the spine
• The affected individuals are reported to have normal intelligence and life expectancy

Additions and Relevant Useful Information for Acromesomelic Dysplasia:

The following DoveMed website link is a useful resource for additional information:

http://www.dovemed.com/diseases-conditions/rare-disorders/