Children with PWS are generally as healthy as other children and in that regard are prone to the same childhood illnesses and diseases.

However, there are some unusual features of PWS which require special attention. These may not always be evident to those who have little experience of the syndrome or when the unusual features are subtle or mild and hence more difficult to identify.

The particular features are included in this article, along with some health issues which are quite common in children living with PWS. But remember, all infants are individuals who will develop their own personality and abilities at their own pace.

Issues which occur only in infancy

Hypotonia (low muscle tone) makes sucking more difficult. Failure to thrive, or poor weight gain, is the major problem in many infants with PWS. Most have a weak cry and are quite sleepy.

Respiratory problems are common in these infants and assistance with clearing secretions may be needed. Insufficient fluid intake, due to feeding difficulties, can occur.

An infant fed by nasogastric tube needs close monitoring, due to the risk of aspiration.

Vaccinations

Unless your GP or paediatrician advises otherwise, your child should receive ALL the usual childhood vaccinations against disease. There are unlikely to be any side effects from these, other than those usually experienced.

Please note that the issues listed below vary considerably between individuals living with PWS and not all children will necessarily have them all. As time goes by, you will be able to identify which of those issues may apply to your child.

Squint (strabismus)

A squint, where one or both eyes look in different directions, is common in babies and children with PWS, and is most likely due to poor muscle tone. Corrective treatment is by patching or a simple surgical operation. See the article ‘Vision and care for the eyes’.

Orthopaedic risks

Scoliosis and kyphosis

Children with PWS have a high risk of developing scoliosis (curvature of the spine to one side) and kyphosis (excessive forward rounding of the upper back). Hence your child’s spine or back should be examined regularly (or at least once a year as a minimum) to identify if they have scoliosis and to institute any intervention, if needed.

Scoliosis develops in children with PWS for several reasons. Children do have poor muscle tone and poor muscle power; this often leads to poor posture and development of scoliosis. Often associated obesity or increased weight can make the scoliosis worse.

Parents worry that treatment with growth hormone can precipitate or worsen the scoliosis. Research suggests that growth hormone is generally safe and does not cause an increased incidence of scoliosis. However, in those who already have scoliosis, it may worsen and hence should be monitored more closely. If a particular child has severe scoliosis, then growth hormone therapy is contra-indicated.

Conservative measures like good posture, good care of the back and physiotherapy are all helpful and useful. Generally, no other treatment is required for mild scoliosis. However, for moderate to severe scoliosis, interventions are needed (such as a spinal brace). In very severe and complex cases of scoliosis (and additional kyphosis or forward bending of the spine) surgical intervention may be needed.

Hip dysplasia

Hip dysplasia is a condition where the socket of the hip is too shallow to fit the ball of the hip. Hip dysplasia has been reported in 8-30% of infants with PWS, but the prevalence could be higher due to sometimes not properly evaluated or diagnosed.

If hip dysplasia is detected in a baby with PWS, the best course of action isn’t yet clear. Hip dysplasia can be treated, usually by bracing or a casting. However, these approaches restrict movement and may do more harm than good for general motor development. In the case of PWS, continued growth, activity and development may allow the issue to ‘fix itself’ without intervention. However, the concern about not treating hip dysplasia is that it may led to pain and arthritis later in life, and, at its worst, lead to the person needing total hip replacement.

Respiratory problems/Obstructive sleep apnoea

Children with PWS may have respiratory problems and are prone to chest infections. Sleep apnoea (where the child momentarily stops breathing while asleep) is sometimes seen in children with PWS. This is exacerbated when the child also has increased weight gain or obesity. When sleep apnoea is suspected, please alert your doctor because this will require further specialist investigations and treatment as appropriate.

Risk of choking

Choking happens when food or fluids gets into the airway, rather than going into the stomach. This can happen in any child, but lack of vomiting reflex makes it more difficult and trickier to identify in a child living with PWS. Hence, do not try to feed your child faster than they are able to cope with. Always ensure that the feeding is supervised. Research has shown some people have problems with swallowing (silent aspiration) and may need a formal test.

Undescended testes in boys

Undescended testes are quite common in boys with PWS. Your paediatrician will advise you on the timing for the best course of treatment, which often involves a simple operation to bring down the undescended teste(s).

Bruising

Many children living with PWS can bruise easily. Additionally, they may not cry out at the time of injury or accident, due to high pain threshold. Hence the presence of a bruise should alert you to actively look for any other signs of an injury in the child.

Temperature

A child living with PWS may have below-normal temperatures at times and may not have a high temperature even when seriously ill. Even slight temperature elevations should be considered as a warning sign to observe your child closely for any other clues. If in doubt, please ask your doctor to examine them.

Vomiting/abdominal pain

Individuals with PWS do not commonly exhibit a vomiting reflex. Many babies with PWS are rarely sick, even when unwell. If your child does vomit or has a fever, or is not responding as they usually do, you should seek a doctor’s help, to check them out.

High pain threshold

Individuals with PWS frequently have decreased sensitivity to pain and thus there is a potential danger of underestimating the problem.

Also, as PWS babies may have a weak cry, they may not be able to alert you if they are experiencing pain. Thus, all known injuries must be assessed by a GP or paediatrician to exclude any serious problems. In time, you will be able to recognise subtle signs when your child is out of sorts or unwell.

Following a significant fall or other injury, your child should be closely monitored for a change in posture, walking or movement of limbs. Observe for deformities, swelling or bruising as these may indicate an injury.

Low cortisol levels

Cortisol is an important stress hormone which the body produces all the time, but increases the production to help deal with illness, infections, or stress. There have been several studies looking at adrenal function in individuals with PWS. A study from Holland raised the possibility that deficiency of cortisol was much more common than expected in PWS; however later studies have not reproduced this result.

Individuals living with PWS are probably more likely than the rest of the population to have cortisol deficiency. However, the current guideline suggests that individuals are not tested routinely. But a test should be done if there is a regular reoccurrence of infections.

Anaesthesia

There is nothing inherent in PWS which gives cause for concern with the administration of anaesthesia. However, all individual health problems related to PWS should be considered. These include:

• Obesity (may be associated with obstructive sleep apnoea, high blood pressure, poor breathing pattern (hypoventilation) which is further exacerbated by hypotonia or poor muscle tone etc.).
• High pain threshold (see above).
• Temperature instability – you should inform the anaesthetist about your child’s usual temperature.
• Food seeking behaviour is common in children with PWS, though generally not in infants. However, the anaesthetist or health professional should assume that your child has eaten and has food in his stomach, unless you can verify otherwise.
• Low muscle tone (especially in infants) may cause difficulties in their ability to cough and clear secretions from their airway. In addition, thick saliva may further complicate airway management.
• Excessive post-operative drowsiness may be present in some children. Further information about anaesthesia can be found on the Prader Willi Syndrome Australia flyer ‘Information for hospitals and Emergency Dept staff’.

PWS Specialist Clinics

You can find specialised clinics for children living with PWS at the Royal Children’s Hospital, Melbourne and the Sydney Children’s Hospital, Randwick. Plans are under way to also develop centres of excellence in Brisbane and Sydney that may be able to offer virtual clinical consultations.

These clinics allow you to see several specialists in one day and are staffed by professionals with a special interest in PWS.

Disclaimer: The content on this website is for information only and cannot be relied on for personal decisions. Everyone is an individual and needs to seek the advice of relevant professionals. Links and resources on htis site are the views of others which change from time to time and are not being endorsed by Prader-Willi Syndrome Australia Ltd or any of its officers, employees, contractors or associates.

Thank you ….

to Georgina Loughnan, Royal Prince Alfred Hospital, Sydney; PWSA UK; Dr Shankar Kanumakala, PWS Clinic, Royal Alexandra Hospital, Brighton; Dr Nicola Bridges, PWS Clinic, Chelsea & Westminster Hospital, for sharing their original source material.