About Primordial Dwarfism

Primordial has been defined as belonging to or being characteristic of the earliest stages of development of an organism. Therefore, Primordial Dwarfism is a class of disorders where growth delay occurs at the earliest stages of development. Unlike some of the other forms of dwarfism where newborn infants can have average lengths, children with Primordial Dwarfism are born smaller than average and have intrauterine growth retardation (IUGR).

 
Conditions Making Up the Class of Primordial Dwarfism

Unlike some of the other conditions described on this website, primordial dwarfism is not a specific diagnosis.

It is in fact a class of disorders to which at least 5 different conditions are currently grouped:

  • Russell-Silver syndrome
  • Seckel syndrome
  • Meier-Gorlin syndrome
  • Majewski osteodysplastic primordial dwarfism (MOPD) Types I/III
  • MOPD Type II

The Russell-Silver, Seckel and Meier-Gorlin syndromes are relatively well defined entities and we will not discuss them here.

We will limit our discussion to MOPD Type II. Most of the information below can be examined in more detail in Hall et. al (1).

 
How Common Is Primordial Dwarfism?

All of the conditions are quite rare and very little is known concerning the incidences. For MOPD Type II, we estimate that there are no more than
100 patients in the United States and Canada giving a rough estimate of
1 in 3 million.

 
How MOPD Type II Is Inherited

MOPDII has an autosomal recessive pattern. This means that the genetic information from both parents was necessary for the child to have this condition. It also means that parents of children with MOPDII have a 25% chance with each pregnancy of having another child with MOPDII.

 
Causes of MOPD Type II

Everyone has two copies of a gene called pericentrin (PCNT).  MOPDII results when there is a gene change (mutation) in each copy of an individual’s pericentrin gene, causing both copies to be nonfunctional (2).

 
Physical Characteristics

Probably the most consistent physical characteristic in these children is severe intrauterine growth retardation (IUGR). Recognition of the deficiency can occur as early as 13-weeks gestation and it becomes progressively more severe over the length of the pregnancy.

At term, infants typically weigh less than 3 lbs and are less than 16
inches in length.This is about the average size of a 28-week premature neonate. However, some children with genetically confirmed MOPDII have been born larger than this. Adult heights are typically less than 33" and the voice is high pitched.

Face & Skull
  • Microcephaly. Head size is proportionate to body size at birth. However, as children grow and develop, the head grows slower than the body and becomes disproportionately small.
  • Premature closure of the soft spots (fontanelles) and craniosynostosis
  • Prominent nose and eyes. The conspicuous nose may be obvious at birth or it may develop over the first year.
  • Small teeth with deficient enamel and increased spaces between them. Small roots in the secondary teeth. Secondary teeth can be missing or lost prematurely.
Trunk, Chest, & Spine:
  • Proportionately small trunk, chest, and spine
  • Scoliosis and thoracic kyphosis in later childhood
Arms & Legs:
  • Disproportionately short forearm in childhood, causing mesomelia
  • Dislocated radial head with decreased range of motion at the elbows
  • Dislocated hips and coxa vara at birth
  • Ligamentous laxity develops with age
Other Characteristics:
  • Fine and relatively sparse hair
  • Pigmentary changes of the skin, such as acanthosis nigricans
What are the X-ray characteristics?

In the newborn, the X-rays typically do not demonstrate major structural abnormalities, although the pelvis is narrow with small iliac wings and flattened acetabular angles. The long bones may be overtubulated. Eleven rib pairs are sometimes seen, rather than twelve. As the children age, the bones appear thin and delicate with progressive metaphyseal widening at the ends of the long bones.

Bone age studies usually show decreased bone age; that is, the skeletal maturation process is slowed in these children and can be delayed 2 - 5 years behind the actual age.

 
Making the Diagnosis

The differential diagnosis for MOPD II is complex and is done clinically based upon history, physical characteristics, radiographic review and the exclusion of any other physical findings or laboratory abnormalities.

There is also research genetic testing available either through Texas
or Scotland that can help confirm what type of primordial dwarfism an individual has.

 
Associated Medical Problems
Nutrition

Most infants with primordial dwarfism have feeding problems, but it is important that the treating physican lower their expectations of daily growth to at least half that of a typical child.

Small volumes and frequent feeding are typical. Sometimes naso-gastric feeding or g-tube feedings are used.

Brain

Some patients have structural or myelination abnormalities in the brain. Structural abnormalities have included: enlarged ventricles, abnormal gyral patterns and abnormal corpus callosum.

Development

Precocious puberty has been described in girls with breast development as early as 7 and menarche, or the beginning of periods, at 9 years. Boys do not seem to have precocious puberty.

 
Recommended Monitoring

Renal or kidney anomalies have been described and a renal ultrasound should be done as the diagnosis is being established.

Most of the patients develop farsightedness which requires glasses. Careful ophthalmologic evaluation is indicated at regular intervals.

A vast majority of individuals with MOPDII have had abnormalities in the cerebral vascular system, including moyamoya disease and aneurysms, which can predispose to stroke. Screenings with MRA/CTA of the brain should begin at diagnosis of MOPDII and continue every 12 to 18 months thereafter to permit early detection of these conditions. If diagnosed in the early stages, revascularization and aneurysm treatment can be performed safely and effectively. (3)

Insulin resistance is associated with MOPDII and can often progress to frank diabetes. Yearly screening labs should begin by 5 years of age and include: hemoglobin A1C, insulin levels, fasting blood sugars, liver functions and lipid profiles. The physician should maintain a high degree of suspicion and if any signs or symptoms develop, further testing is indicated. If changes are present, appropriate follow-up and management plans can be implemented. It does appear that these patients respond well to an oral antihyperglycemic medication like metformin. (4)

A yearly CBC should also be obtained as some children, especially post-pubertal girls, have developed anemia. Furthermore, it does appear that baseline platelet counts may be elevated. The clinical significance of this remains to be determined.

 
References
  1. Hall JG, Flora C, Scott CI Jr., Pauli RM, Tanaka KI. Majewski osteodysplastic primordial dwarfism type II (MOPDII): natural history and clinical findings. Am J Med Genet A. 2004 Sep 15;130A(1):55-72.
  2. Rauch A, Thiel CT, Schindler D, Wick U, Crow YJ, Ekici AB, van Essen AJ, Goecke TO, Al-Gazali L, Chrzanowska KH, Zweier C, Brunner HG, Becker K, Curry CJ, Dallapiccola B, Devriendt K, Dörfler A, Kinning E, Megarbane A, Meinecke P, Semple RK, Spranger S, Toutain A, Trembath RC, Voss E, Wilson L, Hennekam R, de Zegher F, Dörr HG, Reis A.  Mutations in the pericentrin (PCNT) gene cause primordial dwarfism. Science. 2008 Feb 8; 319(5864):816-9.
  3. Bober MB, Khan N, Kaplan J, Lewis K, Feinstein JA, Scott CI Jr, Steinberg GK. Majewski osteodysplastic primordial dwarfism type II (MOPD II): expanding the vascular phenotype. Am J Med Genet A. 2010 Apr;152A(4):960-5.
  4. Huang-Doran I, Bicknell LS, Finucane FM, Rocha N, Porter KM, Tung YC, Szekeres F, Krook A, Nolan JJ, O'Driscoll M, Bober M, O'Rahilly S, Jackson AP, Semple RK; for the Majewski Osteodysplastic Primordial Dwarfism Study Group. Genetic Defects in Human Pericentrin Are Associated With Severe Insulin Resistance and Diabetes. 2011 Mar;60(3):925-35. Epub 2011 Jan 26.

Trusted Insights from Nemours' KidsHealth

Relaxation Techniques for Children With Serious Illness

Managing Stress

Nothing about serious illness is easy, but one of the hardest things for parents may be watching their child struggle with pain, stress, and anxiety.

Despite what we may sometimes tell ourselves, stress is not just "in our heads." The stress response — also called the flight-or-fight response — causes a rush of adrenaline and other hormones that trigger physical changes in the body: your heart races, your blood pressure rises, you breathe faster, your digestion slows, and your pupils dilate. Chronic stress takes a toll on the body as well as the mind.

The good news is that using a variety of mind-body relaxation techniques can help short-circuit the flight-or-fight response. Relaxation techniques not only can lessen a child's physical symptoms, they can also help him or her (and you!) regain a sense of control and confidence over a situation, helping everyone find moments of peace amid the chaos and isolation of illness and medical treatment.

Techniques That Can Help

These techniques are designed for parents and kids to practice together. Most can be done in a few minutes wherever you are, whether that's a quiet place or a crowded hospital, without any special tools.

However, it's important to note that these techniques should be used as a complement to conventional medical treatment for anxiety and pain, and not as a replacement — doing so could do a child more harm than good.

If your child is suffering from anxiety or pain, ask your doctor what can be done to help. And always check with your health care team to make sure that your child's symptoms are related to stress and not a different medical problem.

Focused Breathing

Pain and stress can leave a child breathing faster and shallower, or even holding his or her breath — all of which can actually keep the stress response going and heighten the intensity of pain. Paying attention to breathing can help calm the mind.

Try this exercise with your child:

  • Step 1. Sit or lie comfortably and put one hand on your stomach, the other on your chest.
  • Step 2. Close your eyes and try to relax all of your muscles, one by one, from the tips of your toes to the top of your head. Don't forget to relax the muscles in your face, neck, and jaw; you may be storing a lot of tension there.
  • Step 3. Breathe deeply and regularly for several minutes— and try to make your stomach (abdomen) rise and fall, not only your chest. This will help you deepen your breath.
  • Step 4. Pay attention to each breath; try to turn all your thoughts to each inhale … exhale. As you breathe out, imagine the tension leaving your body with the breath.

At first, it may be difficult for you and your child to focus on breathing. Distracting thoughts are normal — but rather than following a thought and letting it consume you, try to let it drift out of your mind, like a balloon.

Relaxation Response Method

This technique asks a person to focus on breathing and quiet the mind to create a sense of calmness and well-being. And by repeating a word, phrase, or prayer during the exercise, the mind is able to stay focused more easily. When practicing this, it's normal for thoughts to pop into the mind. Tell your child to disregard them and just focus on the word or phrase he or she is repeating.

Resembling an Eastern form of meditation, this technique — called the relaxation response — was popularized and put into Western practice in the 1970s by Herbert Benson, MD. To elicit the relaxation response, follow Steps 1-4 above, and then:

  • Step 5. Pick a focus word, phrase, sound, or prayer such as "om," "one," or "peace."
  • Step 6. As you breathe, say the focus word silently to yourself as you exhale.
  • Step 7. Continue for 5 or 10 minutes, ideally building up to 10 to 20 minutes for each session.
  • Step 8. When you're finished, do not stand up immediately. Continue sitting quietly for a bit, letting other thoughts back into your mind. Open your eyes, but stay sitting for another minute before getting up.

When practicing, go at your own pace. Don't feel like you have to achieve a deep level of relaxation right away. Often, feelings of calmness and well-being are felt later on or at times of crisis.

To achieve ongoing results, try to practice the technique with your child once or twice daily, but not within 2 hours after eating, as digestion can interfere with the relaxation response. Some people find that the best time to meditate is first thing in the morning, before breakfast.

Guided Imagery

A growing body of medical research suggests that imagery also can help lessen pain and anxiety, and promote positive feelings. In fact, studies have found that people who practice guided imagery during chemotherapy feel more relaxed and positive about their chemo experience than those who don't use the technique.

Guided imagery (also called "visualization") often works best when a person starts with a few minutes of focused breathing. Here's how it works: With eyes closed, imagine a safe place or a location you once visited that brought a feeling of contentment and joy. Hold on to the image of that place for a while, trying to picture all the sights and sounds:

  • What does the ground beneath you feel like? Is it weather warm or a chilly? Is there a breeze?
  • Are there any animal noises in the distance, or nature sounds (like running water) that you could hear?

Getting as descriptive as possible about this safe place will help you and your child get "into" the moment and feel relaxed.

Some children find this exercise more helpful when they are "guided" by a parent, another live instructor, or with a guided imagery CD or DVD.

As with meditation, distracting thoughts will float into the mind as you practice guided imagery. Acknowledge these thoughts, and then let them drift away while you move your attention back to the images in your mind and sounds you hear.

Music Therapy

Just as pleasant images can calm the mind and soothe the body, so can music. Kids who undergo music therapy — the research-based use of music to lift moods and promote mental and physical well-being — have been found to have lowered heart rates and blood pressure, and improved anxiety.

Many hospitals provide a licensed, trained music therapist who can work individually with kids to develop a customized treatment plan that engages them in:

  • active play that includes listening to music
  • dancing or moving the body to music
  • playing instruments or improvising on them
  • singing along

To participate in music therapy, your child doesn't need to read music or have any special musical talents. And the best part is that you can practice music therapy at home. By choosing music that both you and your child enjoy — and setting aside time to listen, dance, sing, or experiment with an instrument together — you, too, can teach your child the joys of music.

Energy Therapy

Energy therapy is based on the theory of bioelectromagnetics, the belief that the electrical currents in all living organisms produce magnetic energy fields that extend beyond the body. Proponents of this therapy believe that gentle, light touch or above-the-body hand movements can redirect energy to places where it's needed in an effort to bring energy into "balance" or harmony.

While the principles of energy therapy have not been scientifically proven, practitioners say it promotes healing and helps kids feel more relaxed, less anxious, and less bothered by pain.

Many different types of energy therapy are practiced all over the world, including therapeutic touch, healing touch, Reiki and Johrei (from Japan), and Qi gong (from China).

In the United States, some hospitals offer therapeutic or healing touch as a complement to standard treatments for anxiety, pain, or other medical problems.

And some nurses, doctors, or other health care providers are certified in healing touch techniques. They may be able to offer this service to your child, or teach you how to practice healing touch at home.

Massage Therapy

If you like to take a more hands-on approach to soothing and comforting your child, you might prefer massage. The benefits of massage are well known, offering muscle relaxation and increased blood flow and oxygen to body parts to help alleviate stress and ease pain.

But some types of massage are not recommended for certain types of conditions, so check with your doctor first before massaging your child or taking your child to a massage therapist.

The most common forms of massage used in complementary medicine include:

  • Swedish massage. Therapists use their hands to move muscles and joints with long, gliding strokes, tapping movements, friction (made by moving hands quickly) and kneading. Massage oils may be used, so be sure to tell the therapist about any allergies or sensitivities to ingredients that your child may have.
  • Deep-tissue massage. Many of the same techniques are used as in Swedish massage, only therapists apply more pressure to specific areas, concentrating on the deeper layers of muscles and connective tissue.
  • Trigger-point massage. Like deep-tissue massage, this technique massages deeper layers of tissue, focusing on what therapists call trigger points ("knots") within the connective tissue or muscles that are usually painful when pressed.

Many hospitals have massage therapists on hand to offer massages to both patients and their family members, so find out if massage therapy is offered at your hospital.

Learn More

These are just a few of the many methods designed to help patients and families cope with pain and anxiety. Many people find that yoga, stretching, or light, gentle exercise also helps to quiet the mind and sooth the body.

To learn more about relaxation techniques, talk to your child's health care team.

Reviewed by: Larissa Hirsch, MD, and Walle Adams-Gerdts, RN, BA, HTCP/I
Date reviewed: April 2011