Down syndrome definition
Down syndrome is a naturally occurring chromosomal variation that can be found in people of all races, nations, socio-economic backgrounds and genders. Although there is still much to discover about Down syndrome, we know that it begins in the early stages of cell division around the time of conception.
Three different patterns
A blood test is used to determine a baby’s type of Down syndrome.
- Trisomy 21
Ninety-five per cent of people with Down syndrome have trisomy 21, which means that there are three copies of chromosome 21 in each cell instead of the usual two.
Two to three per cent of people with Down syndrome have a translocation pattern. In translocation, part of #21 chromosome breaks off and attaches to another chromosome - usually #14. Most translocation happens on its own, but sometimes it is a trait inherited from a parent. Through testing, parents can discover whether the children they bear in the future have an increased likelihood of having Down syndrome.
Two per cent of people with Down syndrome have mosaicism. A variance occurs in cell division at the point of conception. Some cells have 46 chromosomes; some have 47.
Many babies with Down syndrome have distinctive characteristics about their appearance that do not affect their health:
- a flat nose bridge
- skin folds at the inner corners of their eyes
- small ears
- curved pinky fingers
- gaps between their first and second toes
Common Health Concerns
Children with Down syndrome may face health complications beyond the usual childhood illnesses. Problems such as some congenital malformations of the heart can be life-threatening where other conditions are not as serious. More than 40 per cent of children born with Down syndrome have a congenital heart malformation. Because of this high incidence, an echocardiogram is recommended. The diagnosis of a heart problem does not mean the baby is, or will become, seriously ill. The extent of heart problems varies greatly.
Hypothyroidism is more common in newborns and children with Down syndrome. It is important that blood tests are repeated several times in the first few years, and annually after that, to ensure early detection and appropriate treatment.
Some degree of hearing loss, which is most often due to frequent ear infections, affects a high percentage of children with Down syndrome. Adequate hearing is critical to the development of good language skills, so periodic medical check-ups should include visualization of the ear canals to ensure no infection is present. Vision problems are also fairly common in many children with Down syndrome. An ophthamological exam is recommended during the baby’s first year.
No individual with Down syndrome will have all the health complications, however, every child needs good preventative medical care. Teamwork between the family and doctors is vital to anticipate potential problems and provide specific and individual treatment should they occur. Appropriate health care can enhance the potential of individuals with Down syndrome.
The following additional assessments are recommended for children with Down syndrome.
Congenital (defects existing from birth) heart disease occurs in many children with Down syndrome. It can be present even when a murmur is not heard. An ECHO cardiograph is worthwhile. Many children born with heart defects can have these problems reversed with surgery.
Most children with Down syndrome tend to have small ear canals, making ear infections and structural ear problems common. Many children have some hearing loss, often due to fluid build-up. This can begin as early as the newborn stage. Regular ear exams can monitor your child’s hearing. A brain stem evoked response (ABR) is also recommended. This measures responses in brain waves that are stimulated by a clicking sound to check the central auditory (hearing) pathways to the brainstem.
About half of children with Down syndrome have eye problems or vision loss. Eye exams from birth can ensure your child’s vision is properly monitored and supported.
Individuals with Down syndrome commonly experience thyroid disease, which can occur at any age. Blood tests can best monitor that your child’s thyroid levels are normal.
Early Childhood Development
You may have known before your baby’s birth that they have Down syndrome, or you may have found out after they were born. There are several indications in a newborn which would make health care professionals think that your baby might have Down syndrome, but only a diagnostic test (karyotype) confirms it. Some of the symptoms have no medical connection- they include:
- Almond shaped eyes
- Light spots in the colored portion of the eyes
- A crease across the palm
- Small, low set ears and nose
- Low muscle tone
People with Down syndrome have extra genetic material associated with the 21st chromosome; how this genetic material will effect them us unique to them. There is no way of knowing how healthy your child will be, or how he or she will develop socially or intellectually, just as with all children!
Down syndrome itself does not require either treatment or prevention. However, the extra genetic material in your baby’s cells can affect their health so it is important that your baby is receiving good medical care. Your baby will be weighed to ensure that they are gaining adequate weight as often as babies with Down syndrome are smaller.
Heart problems are common, including congenital heart disease ( a heart problem present at birth). Every newborn with Down syndrome should have an EKG and ECHO cardiogram before the age of four months. Many heart defects can be reversed with surgery. Your baby will be checked for any stomach or bowel problems. Most problems usually occur after birth and can be corrected surgically. Your physician will also check your baby’s thyroid function, vision and hearing.
It is recommended that within the first three to six months of your baby’s life that he or she is enrolled in an infant stimulation program to help your baby’s development. A developmental evaluation is recommended at one year- occupational, feeding and speech therapy can determine your baby’s area of strengths and needs.
Continued speech and motor therapy assessments are beneficial to monitor your child’s development. A complete education assessment is recommended every three years, especially before your child enters school. Community supports like respite and counseling are available if beneficial to your family.
Your child with Down syndrome will grow and develop much like other children without Down syndrome. During this time period, there are some health concerns to be aware of.
An annual check-up with your physician is important. Review with your doctor any infections, ear problems, constipation, eye problems, or snoring (possible sleep apnea). Discuss with your doctor any possibilities of congenital heart disease, hypothyroidism, low caloric intake, etc.
School-aged Child Development
Similar to when you were your child was a newborn, annual thyroid tests are recommended. Ear tests are beneficial, especially if your child has a history with ear infections. Talk to your doctors about screening for Celiac disease, if you suspect your child has digestive difficulties.
A neck X-ray at three to four years of age (and then again between 10 to 12 years old) can determine if your child has Atlantoaxial instability- instability where the neck connects to the spine. Radiographic screening is also recommended between the ages of two to three to assess for Atlantoaxial instability.
Like other children, an initial dental examination before two years old is recommended, with a follow-up at 6 to 12 month intervals. A balanced diet and exercise program are important to avoid childhood obesity.
Children with Down syndrome benefit from quality inclusive education settings, and the opportunity to learn from and with their peers. Early intervention programs, used to identify and support the learning needs of each individual will ensure better and more frequent inclusion in our community schools.
Young Adult Development
Your teenager should continue having annual physical exams, including an pelvic and pap smear for women with Down syndrome. Annual eye, thyroid and hearing monitoring is recommended. Talk to your kids about smoking, alcohol and drugs.
Your physician should refer an X-ray for Atlantoaxial instability at 18 years of age, and after the age of 30. A neurological exam can assess problems with seizures and symptoms of dementia which, in some individuals, can appear as early as 30 to 40 years of age.
Twice yearly dental exams, a low-calorie diet and daily exercise are always important. Your child’s school program should include plans for employment, independent living and sexual education. Attention to these issues can help ensure a life of contribution, engaged citizenship and meaningful relationships for your child.