Common Medical Questions

June 3, 2024 Chromosome 22 Central

Why do Chromosome Differences Cause Medical Problems?

We do not know exactly, but in general, having extra copies or missing copies of certain genes can affect how our bodies develop, grow, and function. “Common Chromosome Medical Questions” – an excerpt from Raising the Goddess of Spring: A guide for parents raising children with rare chromosome disorders

How Can the Brain be Affected?

Some chromosome disorders cause structural differences in the brain (which might be visible on an MRI or a CT scan), and others cause functional differences, which changes how the brain does its various jobs (like thinking, moving the body, and responding to the environment). Some chromosome disorders make the brain more susceptible to having seizures, which are sudden electrical discharges in the brain, which can momentarily affect motor movements, behaviour or breathing. Brain differences can cause abnormalities in muscle tone. Many children have hypotonia (low muscle tone) or hypertonia (high muscle tone). Problems with muscle tone can lead to delayed motor milestones, difficulties with feeding and talking, constipation (because the muscles in the bowels are affected), and scoliosis (spine curvature).

Other types of brain differences can lead to movement disorders such as ataxia (poor balance due to problems with the cerebellum). Intellectual functioning is often, but not always, affected by chromosome disorders.

How Might My Child’s Vision be Affected?

Chromosome differences can either cause all sorts of eye problems or none at all. Common vision problems include nearsightedness (myopia), farsightedness (hyperopia), astigmatism, and strabismus (lazy or wandering eye). In babies, you should watch for visual attention—that is, does your baby look at faces, follow objects with his eyes, pay attention to toys held off to the side? Are her eyes moving together, or does one or both tend to drift sideways? Are the eyes still, or do they shake (nystagmus)? Do one or both eyes look cloudy (this could be a sign of cataracts)? For older children, does he sit very close to the TV or hold books up to his face to look at them? Does he squint his eyes when looking at things that are close or far away? Does she complain of eye pain, eye-watering, blurry or double vision?

If you have any concerns about your child’s vision or eyes, you should talk to his doctor. A lot of eye problems can be corrected, and doing so early can prevent further eye damage later in life.

Are Hearing Issues Common?

Hearing problems are very common in children in general, and perhaps a bit more common in children with chromosome differences. Many countries do a hearing test on babies right after birth, but hearing problems can develop in later years as well. The most common kind of hearing loss is called conductive. This type of hearing loss happens when something is blocking the sound from outside, on its way to the part of the brain that processes sound. The most common causes are ear wax and fluid in the middle ear. Your child’s doctor can look inside his ears to see if anything is blocking the sound from getting in. Other causes could be related to how the ears formed on the inside (middle and inner ear). If your child’s doctor suspects a middle or inner ear problem, she might be referred to a specialist called an otolaryngologist (or ENT—ear, nose and throat—doctor).

Less common, but important, hearing problems that can be associated with chromosome differences are referred to as sensorineural hearing loss. This is often due to a problem with the brain itself, or the nerves that carry information from the ear to the brain.

Why Is Drooling a Problem, and Can We Control It?

Typically developing children may drool when they are very young, but eventually, this stops when they develop better control of their swallowing. And we all drool in our sleep sometimes! Children with low muscle tone may drool excessively, or beyond the normal time, because they cannot control the muscles of their mouth very well. It is not usually because of too much saliva—they just do not swallow their saliva effectively.

Drooling can be a nuisance because your child’s clothes get wet, and their lower face may become chapped from too much moisture. It can also be embarrassing for the child. It is best to get a doctor’s opinion about the cause of the drooling, especially if it starts again after your child has learned to control her drooling. It could be due to pain or infection in the teeth, throat, or chest (like heartburn). Her nose could be blocked, forcing her to breathe with her mouth open. Most of the time, though, it is an ongoing problem due to hypotonia. You cannot make the hypotonia go away. Still, some medications can reduce drooling by drying up the saliva (although they can have some unpleasant side effects, like constipation). In severe cases, your doctor may suggest Botox injections into the salivary glands, which also reduces saliva production, but only lasts a few months. Another solution is surgery to decrease saliva production permanently. This surgery is usually only done when a child cannot control the swallowing of saliva to the extent that he aspirates (breathes saliva into the lungs), which can be life-threatening.

Why is Chewing, Swallowing, and Feeding So Challenging?

Every child is different, so it is best to have a feeding specialist assess your child. Often the underlying causes are due to differences in how the brain works. Sucking, chewing, and swallowing, and coordinating those actions with breathing, are second nature to most of us, but might not be to your child. A feeding specialist can help you to ensure your child gets adequate nutrition while minimizing the risk of choking and aspiration.

What Breathing Issues Might my Child Experience?

Some children will not experience any breathing issues. Others may have difficulty breathing on their own when they are first born and may be on a ventilator (breathing machine) for a while. It is uncommon, but some children are never able to breathe fully on their own, and therefore need a tracheostomy (a permanent breathing tube in the neck).

Children with hypotonia can be prone to chest (lung) infections, which may be caused by aspiration, viruses or bacteria. Signs of infection may include fever, cough and difficulty breathing. If you think your child has a chest infection, she should see a doctor. She may or may not need antibiotics, depending on the underlying cause. If your child gets recurrent pneumonia (more than once a year), or particularly severe breathing problems when sick, her doctor might recommend additional vaccines (like the flu shot), medications (like an inhaler for asthma) or a feeding tube (if she is aspirating food or saliva).

My Child Has Difficulties with Sleep. Why?

There is no “one size fits all” answer to this question. Sleep problems are common in children and have multiple causes. Some children have problems falling asleep, while others do not sleep long enough. Some children do not sleep well at night and then sleep too much during the day. Some will snore or have pauses in their breathing (apneas) during sleep or have seizures during the night. If your child takes medication, poor sleep might be a side effect. Some children have learned that calling out at night brings them attention from parents, which reinforces nighttime waking. Any of these issues could be at play. If sleep problems last more than a few weeks, see your doctor. Read more about sleep issues in Chapter 8.

How Can Chromosome Disorders Affect Heart Structure and Function?

Some people with chromosome disorders are born with one or more heart defects. Heart defects can be evident at birth (usually because the baby has blue skin and does not “pink up”) or have no symptoms at all. By listening to your baby’s chest, the doctor can tell you if she hears a murmur, which is a sound made by the blood pumping through the heart with narrow vessels or abnormal passageways (holes). Not all murmurs are a sign of a problem, though. There are many kinds of heart defects, and some do not need any treatment, while others require surgery or even a heart transplant.

What Digestive Challenges Might Be an Issue?

The most common digestive problems are gastroesophageal reflux (GER) and constipation. Often when a person has low muscle tone, this does not just affect the arms and legs, but also the muscles inside the body. Our gastrointestinal tracts are lined with a special type of muscle called smooth muscle, and if muscle tone is low, this can slow the whole system down. So, the stomach might empty slowly (which can lead to reflux or vomiting), and food will travel more slowly through the bowels (which can lead to constipation). Sometimes your child’s doctor will recommend medications to treat these problems, or dietary changes, or both.

What Types of Problems Can Affect the Genito-Urinary System?

The genito-urinary system includes the kidneys, bladder, and internal and external genitalia. Any of these organs can form differently in children with chromosome disorders. A malformed kidney may not function as well, but on the other hand, it may not cause any problems (especially if the other kidney is working well). Some children are more prone to urinary tract infections. Some boys may have undescended testicles or hypospadias (where the opening at the end of the penis is not in the right place), which needs to be surgically corrected. Certain types of sex chromosome disorders have more substantial effects on the development of the genitalia and puberty. Puberty is usually normal in other types of chromosome disorders, but occasionally it will start early or late.

How Might My Child’s Bones and Joints be Affected?

It is possible that your child’s bones could grow more slowly, which could mean that she is shorter or smaller than her peers. Sometimes chromosome differences can affect the shape of the bones, which may not cause any problems (like a curved little finger, bowed legs, or mild scoliosis) or may need treatment (like severe scoliosis, congenitally dislocated hips, or club feet). Some older children and adults may develop weak or brittle bones (low bone density or osteoporosis), especially if they are not able to weight-bear or they are taking certain medications. Weak bones can lead to fractures, which in turn can lead to pain. Supplementing the diet with calcium and vitamin D is often recommended for those at risk of low bone density; in more severe cases, medications like bisphosphonates can be given.

If your child has high muscle tone (hypertonia), he may develop contractures over time. Contractures cause joints to have a limited range of motion and can interfere with the child’s ability to move his arms and legs. At the other extreme, some children have joint hypermobility, which can lead to painful dislocations or, over the long term, arthritis.

How do I Ensure that my Child Stays as Healthy as Possible?

It is important to have a good primary care doctor or nurse practitioner who knows your child well. Your child will also get common childhood illnesses in addition to the concerns presented by their chromosome disorder. Your child may ultimately see a lot of specialists, but your family doctor or pediatrician should have your child’s complete medical record available. Try your best to attend medical appointments with your child and bring a current list of all her medications and doses, and any allergies. It sometimes helps to keep a notebook (paper or electronic) with notes from various medical appointments, as it can be hard to remember everything. Always ask questions of your child’s doctor if you do not fully understand. You can ask the doctor to write things down for you if that helps.