Typically, hydrocephalus associated with achondroplasia is mild. But if it is severe or persistent, the doctor can place a shunt , which is like a drain from the brain into the abdomen. Some people with achondroplasia also have apnea or sleep apnea. This is a medical condition where you stop breathing or your breathing slows down while you're sleeping. Examples of other types of dwarfism include:.
Dwarfism can be caused by a genetic condition. It can also be caused by a medical or hormonal condition. The majority of people with dwarfism have gene mutations. This means they have changes in specific genes. These mutations interfere with normal development. They may also affect the growth of the cartilage and bones in the body. Since arms and legs have the longest bones, any problems with normal bone development usually result in shorter limbs.
This leads to short stature. Any genetic change that causes dwarfism can be inherited from parents. It may also develop during fetal development. Two short-statured people can have a non-dwarf child. Average-sized parents can give birth to a child with achondroplasia.
Some non-genetic types of dwarfism can be caused by a growth hormone deficiency. They can also occur if a baby or child's body does not get the nutrients that they need for growth and proper development.
A specialist can usually treat these kinds of dwarfism using growth hormones. Doctors can diagnose some types of dwarfism during early pregnancy with genetic testing. Some cases of achondroplasia can be diagnosed in the late stages of pregnancy through the use of ultrasound, a test that uses sound waves to create a picture of the baby.
Ultrasounds can show shorter-than-average arms and legs, as well as whether the growing baby's head is larger than average. Often, however, dwarfism can't be diagnosed until after the baby is born. Dwarfism itself is not a disease, so there is no "cure. They also lead healthy, active lives. But the conditions that cause dwarfism can cause health complications. These health complications often involve the spine and lower limbs. Some medical issues relating to dwarfism are treated with surgery.
These surgeries are usually performed on the following parts of the body:. Surgical treatments can help improve a little person's quality of life and survival.
If a child is very short, they might not receive a diagnosis of dwarfism when there are no other features besides short stature. Many people who are on the short side of the normal growth spectrum do not have dwarfism. Dwarfism occurs when a person has short stature.
Different things cause dwarfism. Most forms of dwarfism are genetic or inherited at birth. More than genetic conditions can cause dwarfism. This is the most common kind of dwarfism. For example, a genetic condition called achondroplasia results in arms and legs that are significantly shorter than those of a person of average size, but the trunk is like that of someone unaffected by dwarfism.
In some cases, the head of a person with disproportionate dwarfism may be slightly larger than that of a person without dwarfism. Researchers believe there are more than conditions that cause dwarfism. Most causes are genetic.
The most common causes include:. Though achondroplasia is a genetic condition, four out of five people who have it also have two parents who are average sized. If you have achondroplasia, you have one mutated gene associated with the condition and one unaffected version of that gene. This is the most common cause of dwarfism. This condition affects only females. Instead of inheriting two fully functioning X chromosomes from your parents, you inherit one X chromosome and are missing a second, or at least part of a second, X chromosome.
Males, by comparison, have an X chromosome and a Y chromosome. In many cases, the reasons for growth hormone deficiency are never diagnosed. An underactive thyroid , especially if it develops at a young age, can lead to many health problems, including limited growth. Other complications include low energy, cognitive problems, and puffy facial features. The pregnancy may go to full term, but the baby is usually much smaller than average.
The result is typically proportional dwarfism. Dwarfism is usually the result of a genetic mutation. But having a gene or genes responsible for dwarfism can occur in a couple of ways. In some cases, it can happen spontaneously. You may not be born with mutated genes inherited from a parent. Instead, a mutation of your genes happens on its own — usually without a cause doctors can discover. Inherited genetic disorders can take two forms. One is recessive, which means you inherit two mutated genes one from each parent to have the condition.
The other is dominant. You only need one mutated gene — from either parent — to have the disorder. Other risk factors for dwarfism include a hormone deficiency or malnutrition.
Serious malnutrition, which leads to weak bones and muscles, can also be overcome in many cases with a healthy, more nutrient-rich diet. At birth, sometimes the appearance of a newborn may be enough to make a diagnosis of dwarfism. As part of baby wellness exams, your child should be measured and weighed to see how they compare to the population averages for a child their age.
Consistently measuring in the lowest quartiles on the standard growth chart is another sign a pediatrician can use to diagnose dwarfism. Making a tentative prenatal diagnosis while the baby is still in the womb can be done with an ultrasound.
This is a lab test of amniotic fluid from the womb. Genetic testing may be helpful in some cases. Dwarfism is generally defined as an adult height of 4 feet 10 inches centimeters or less.
The average adult height among people with dwarfism is 4 feet cm. Many different medical conditions cause dwarfism. In general, the disorders are divided into two broad categories:. Some people prefer the term "short stature" or "little people" rather than "dwarf" or "dwarfism.
Short stature disorders do not include familial short stature — short height that's considered a normal variation with normal bone development.
Signs and symptoms — other than short stature — vary considerably across the spectrum of disorders. Most people with dwarfism have disorders that cause disproportionately short stature.
Usually, this means that a person has an average-size trunk and very short limbs, but some people may have a very short trunk and shortened but disproportionately large limbs. In these disorders, the head is disproportionately large compared with the body. Almost all people with disproportionate dwarfism have normal intellectual capacities. Rare exceptions are usually the result of a secondary factor, such as excess fluid around the brain hydrocephalus. The most common cause of dwarfism is a disorder called achondroplasia, which causes disproportionately short stature.
This disorder usually results in the following:. Another cause of disproportionate dwarfism is a rare disorder called spondyloepiphyseal dysplasia congenita SEDC. Signs may include:. Proportionate dwarfism results from medical conditions present at birth or appearing in early childhood that limit overall growth and development. So the head, trunk and limbs are all small, but they're proportionate to each other. Because these disorders affect overall growth, many of them result in poor development of one or more body systems.
Growth hormone deficiency is a relatively common cause of proportionate dwarfism. It occurs when the pituitary gland fails to produce an adequate supply of growth hormone, which is essential for normal childhood growth. Signs include:. Signs and symptoms of disproportionate dwarfism are often present at birth or in early infancy. Proportionate dwarfism may not be immediately apparent. See your child's doctor if you have any concerns about your child's growth or overall development.
Most dwarfism-related conditions are genetic disorders, but the causes of some disorders are unknown. Most occurrences of dwarfism result from a random genetic mutation in either the father's sperm or the mother's egg rather than from either parent's complete genetic makeup.
About 80 percent of people with achondroplasia are born to parents of average height. A person with achondroplasia and with two average-size parents received one mutated copy of the gene associated with the disorder and one normal copy of the gene. A person with the disorder may pass along either a mutated or normal copy to his or her own children.
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