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Prader-Willi Syndrome - Treatment & Management

Overview

Although there is no cure for Prader-Willi syndrome (PWS), there are interventions that can significantly help individuals with PWS lead healthier lives. An example is growth hormone (GH) therapy to increase stature, decrease obesity, and increase muscle mass and capacity for physical activity. The management of individuals with PWS is enhanced by a multi-disciplinary approach that includes nutrition, neurology, endocrine, genetics, ophthalmology, psychology, gastroenterology, speech, occupational and physical therapy, and orthopedics. The collaboration of these specialists in a PWS-focused clinic setting offers benefits for patients/families and for developing ongoing improvements in care.

General health is usually good in individuals with PWS. If weight is controlled, life expectancy may be near normal and the individual's health and functioning maximized. The constant need for food restriction and behavior management may be stressful for family members. The national Prader-Willi Syndrome Association (USA) can provide information and support for family members and healthcare providers. Family counseling may also be needed. Adolescents and adults with PWS can function well in group and supported living programs if the necessary diet control and structured environment are provided. Employment in sheltered workshops and other highly structured and supervised settings is successful for many. Residential and vocational providers must be fully informed regarding management of PWS. See Services below.

Primary Care Roles

When specialized multidisciplinary services are available, the Medical Home should collaborate with this team to assure that primary care complements the specialty services and to coordinate services through schools and other community-based services. When no multi-disciplinary clinic is available, the Medical Home may take on the role of helping the family access the various specialists, coordinate that care, and access appropriate community-based services. Managing the care, and particularly the nutrition and behavior, of children with PWS is very challenging - collaborating with and providing support for the family is a key role of the Medical Home provider.

Pearls And Alerts

People with PWS may have unusual reactions to standard dosages of medications. Use extreme caution in giving medications that may cause sedation: prolonged and exaggerated responses have been reported. Carefully monitor respiratory function.

Individuals with PWS may present with central adrenal insufficiency. The amount of cortisol they produce may not be adequate during times of stress (e.g., illness, trauma, or surgery). See [de: 2008] and [Stevenson: 2004].

Water intoxication has occurred in relation to use of certain medications with antidiuretic effects and from excess fluid intake alone.

High pain tolerance or lack of typical pain signals is common and may mask the presence of infection or injury. Someone with PWS may not complain of pain until infection is severe or may have difficulty localizing pain. Parent/caregiver reports of subtle changes in condition or behavior should be investigated for medical cause.

Individuals with PWS may be at increased risk of respiratory problems. Hypotonia, weak chest muscles, and sleep apnea are potential complicating factors. Anyone with significant snoring, regardless of age, should have a medical evaluation to look for obstructive sleep apnea. Infants may be at risk for respiratory failure when they are ill due to the increased risk of obstruction. Laboratory evaluation of respiratory function may be necessary.

Vomiting rarely occurs in individuals with PWS , even when it may be helpful. Emetics may be ineffective and repeated doses may cause toxicity. This characteristic is of particular concern in light of hyperphagia and the possible ingestion of uncooked, spoiled, or otherwise unhealthful food. The presence of vomiting may signal a life-threatening illness.

Children with PWS have increased risk of complications from anesthesia, including trauma to the:

  • airway,
  • oropharynx, or
  • lungs due to anatomic and physiologic differences such as:
    • narrow airway;
    • underdevelopment of the larynx and trachea;
    • hypotonia;
    • edema; and
    • scoliosis.
Particularly with the increasing number of infants and children with PWS undergoing sleep assessments and a potential rise in surgical procedures for obstructive sleep apnea, it is important to alert the medical team to potential complications. See also Postoperative monitoring in children with PWS (PWSA USA).

Abdominal distention or bloating, pain, and vomiting may be signs of life-threatening gastric inflammation or necrosis, which is more common in PWS than in the general population. Rather than presenting with localized pain, there may be a general feeling of unwellness. If an individual with PWS has these symptoms, close observation is needed. An X-ray and an endoscopy exam with biopsy may be necessary to determine the degree of the problem and possible need for emergency surgery.

Temperature dysregulation, resulting in high or low body temperatures, has been reported in PWS without evidence of infection or other known cause. However, hyperthermia may occur during minor illness and in procedures requiring anesthesia. Fever may be absent despite serious infection.

Skin lesions in individuals with PWS, including open sores, caused by skin picking, and easy bruising, may wrongly lead to suspicion of physical abuse. Skin picking is usually in response to an existing lesion or from itching of the face, arms, legs, or rectum. It is best managed by ignoring the behavior, treating and bandaging sores, and providing substitute activities for the hands. Close observation for prolonged bathroom time and other activities should be monitored to avoid self-injurious behavior.

Hyperphagia due to insatiable appetite may lead to life-threatening weight gain, or may lead to stomach necrosis and rupture. Weight gain may be very rapid and occur even on a low-calorie diet. Individuals with PWS must be supervised at all times in all settings where food is accessible.

All individuals with PWS should be considered growth-hormone deficient. The FDA has recognized a diagnosis of PWS as an indication for growth hormone therapy.

In the event of death of an individual with PWS, please contact the Prader-Willi Syndrome Association (USA) Medical Crisis Support (800-926-4797) which maintains a research database of reported deaths. Although most premature deaths are attributable to morbid obesity, cases unrelated to obesity have recently been noted, leading PWSA to recommend a formal investigation of causes of death. PWSA also provides bereavement support to families who have lost children with PWS.

When a child or adult with PWS dies, the family may wish to consider donation of organs for research. PWSA (USA) has established a procedure for Tissue donation to support research on Prader-Willi syndrome to the Brain and Tissue Banks for Developmental Disorders, created by the NIH in cooperation with the University of Maryland and the University of Miami. Prompt action is essential for tissue preservation. Families are advised to contact the closest Brain and Tissue Bank (800-847-1539, Maryland) directly.

Practice Guidelines

Goldstone AP, Holland AJ, Hauffa BP, Hokken-Koelega AC, Tauber M.
Recommendations for the diagnosis and management of Prader-Willi syndrome.
J Clin Endocrinol Metab. 2008;93(11):4183-97. PubMed abstract / Full Text

Systems

Endocrine/Metabolism

Growth hormone is typically deficient in PWS, causing short stature, lack of a pubertal growth spurt, and a high body fat ratio (fat/body weight), even in those with normal weight. (Different centers initiate growth hormone supplementation at different ages.)

Growth hormone (GH) is approved for use in PWS for improvement of body composition, height velocity and linear growth, mobility, behavior and quality of life. Growth hormone therapy may increase muscle mass and function and allow a higher daily calorie intake. Psychosocial development may also be improved. Therapy is initiated at a standard dose of approximately 0.3 mg/kg/wk divided as a daily subcutaneous injection. See the Growth Hormone Policy Statement (PWSA) and the updated guidelines for growth hormones. [Wilson: 2003] Recent reports have noted the occurrence of sudden death during initiation of GH, mainly during sleep and possibly related to severe obesity and sleep disordered breathing (SDB) – more studies are needed to clarify the cause of death in these cases. [Grugni: 2008] [Tauber: 2008]

Because individuals with PWS are at risk for sleep apnea, a sleep study is recommended before beginning GH treatment, with a follow-up study 6-8 weeks later. If there is worsening of obstructive sleep apnea (OSA), then temporarily stopping the GH is recommended until the cause is understood. Frequently the OSA can be corrected by removing the adenoids and tonsils or lowering the dose of GH (if IGF-1 is abnormally high). Thyroid function and cortisol levels (in AM) should also be tested before starting growth hormone treatment. There has been some discussion about adrenal hypofunction in a subset of PWS individuals.

In most individuals with sleep-disordered breathing due to PWS, GH can actually improve (or at least not worsen) the apnea. [Haqq: 2003] [Miller: 2006] [Festen: 2006] Withholding GH from those with sleep apnea may be detrimental, thus monitoring the child with PWS closely when starting GH to make sure that they do not worsen is the recommended approach.

Diabetes mellitus, type II, has been observed in individuals with PWS, particularly in those individuals with obesity. The risk for diabetes is lowered when weight is reduced. Therefore, blood glucose and insulin levels are periodically checked depending upon the level of obesity and use of growth hormone therapy.

Subspecialist Collaborations and Other Resources

Pediatric Endocrinology (see Services below for relevant providers)

Referral and co-management for growth hormone initiation and treatment, monitoring for diabetes mellitus, and possibly for sex hormone replacement.

Pediatric Genetics (see Services below for relevant providers)

Periodic referrals are recommended for collaboration on ongoing management.

Prader-Willi Clinics (see Services below for relevant providers)

If available, management at a PWS Clinic is recommended.

Gastro-Intestinal & Bowel Function

Failure to thrive: Food intake during the first 2 years of life requires close management to maintain weight-for-height measures between the 25th and 80th percentile. Published growth standards specifically for use in PWS are available for children age 2 and older (PWS Growth Charts(PDF Document 431 KB)) and for infants 0-36 month (Growth Standards of Infants With Prader-Willi Syndrome (AAP)—scroll though link's text to find charts). Failure to thrive may necessitate tube feeding. Infants with PWS should be closely monitored for adequate calorie intake and appropriate weight gain. Referral to gastroenterology may be indicated.

Hyperphagia: In older children, hyperphagia due to insatiable appetite may lead to life-threatening weight gain, which can be very rapid and occur even on a low-calorie diet. Excessive uncontrolled over-eating may lead to stomach necrosis and rupture. To control energy intake, a careful food monitoring program is essential for both children and adults with PWS. [Butler: 1991] Restricted caloric intake with vitamin and calcium supplementation, performed under the close supervision of an experienced dietitian, is generally required from age 2-3 years to minimize excessive weight gain and osteoporosis. Successful weight maintenance in children with PWS who have not been treated with growth hormone has been reported with an intake of 8-11 kcal per cm of height per day, whereas children without PWS require 11-14 kcal per cm per day for adequate growth.

Individuals with PWS must be supervised at all times in all settings where food is accessible. Those who have normal weight have only achieved this because of strict external control of their diet and food intake. Involving the patient, family members, and care providers is critical in developing strategies to cope with the hyperphagia and weight and behavior control issues that are characteristic of PWS. [Goldberg: 2002] Tactics include:
  • locking away food,
  • keeping limited amounts of food in the home,
  • continual close supervision of the patient around food or food-related events,
  • providing non-food-related rewards,
  • reduction of portion sizes using small plates and bowls,
  • allowing participation in menu planning and preparation,
  • counting calories, and
  • having access to food with fewer calories.
It is also important to keep strict mealtime regimens and to ensure unwavering consistency by both parents and care providers, both inside and outside of the home. See Food and Behavior in PWS (Pittsburgh Partnership) for more information regarding food security and behavior. Individually tailored exercise programs are encouraged - 30 minutes of sustained activity 3-5 times per week are generally recommended. [Butler: 2006] [Holm: 1976] To date, no medication or surgical intervention has been found that would eliminate the need for strict dieting and supervision around food. Bariatric surgery has generally been unsuccessful and not recommended in PWS. [Scheimann: 2008] See also Obesity and Diet in Prader-Willi Syndrome and Nutrition/Growth/Bone below.

Other: Although they have no known congenital defects involving the gastrointestinal system, children with PWS have decreased sensitivity to gastric fullness and to pain. A decreased pain response may mask the symptoms of gastrointestinal problems such as gastric distention, gastroparesis, and necrosis, which are more common in individuals with PWS. In addition, because vomiting is reduced in children with PWS, they may not respond to eating spoiled or contaminated foods. Children with PWS may present with behavior changes and vague feelings of unwellness that might represent medically urgent gastrointestinal disease. These complaints should be taken seriously by providers. See Emergency alert information for children with PWS.

Gastroesophageal reflux (GER) is common in children with PWS and may be particularly problematic in infants due to their hypotonia. See Gastroesophageal Reflux (general).

Vomiting and rumination: Commonly reported features of PWS include a decreased ability to vomit and a high prevalence of rumination. [Alexander: 1987] Dental enamel defects due to rumination should be looked for routinely. Rumination may increase in children with strict behavioral food intake programs. See Rumination (eMedicine) for more information.

Constipation is common in children with PWS (>20%). Rectal ulcers, which may occur due to skin picking, can be exacerbated by large stools and constipation. See Constipation Treatment (general) for information about the evaluation and treatment of constipation. Treatment of bowel disorders in individuals with PWS often requires ongoing specialized treatment and monitoring with a multi-disciplinary approach to optimize therapy. See also You Can Poop Too Program. The following tools may be helpful: Bowel Management Algorithm(PDF Document 47 KB); Bowel Management Parent Information; Bowel Management (general)(PDF Document 74 KB); Constipation Evaluation Tool(PDF Document 84 KB); and Home Toileting Record(PDF Document 49 KB).

Subspecialist Collaborations and Other Resources

Pediatric Gastroenterology (see Services below for relevant providers)

A referral to gastroenterology may be helpful for management of failure to thrive, and hyperphagia, severe reflux, or constipation.

Nutrition/Dietary (see Services below for relevant providers)

It is important to involve nutrition expertise on a regular basis for both failure to thrive and the restricted diet necessary for children and adolescents with PWS.

Pediatric Genetics (see Services below for relevant providers)

Periodic visits with genetics are helpful for management of growth issues specific to PWS.

Prader-Willi Clinics (see Services below for relevant providers)

When available, management at a PWS Clinic is preferred.

Mobility/Function/ADLs/Adaptive

A number of nutritional issues arise in children with PWS. These include problems with poor feeding and failure to thrive in early infancy, often requiring the use of special nipples or tube feedings. These generally start to improve by 6 months of age, however insatiable appetite and the resulting risks may begin by 12 months of age. Some of these risks are addressed under Gastro-Intestinal above. For more detail, please see the Nutrition and Diet in Prader-Willi Syndrome (Medical Home Portal) Issue Page.

Subspecialist Collaborations and Other Resources

Nutrition/Dietary (see Services below for relevant providers)

It is essential to involve nutritionists familiar with this disorder in diet planning.

Skin & Appearance

A common problem that may become a habit in children with PWS is scratching and picking at the skin or mucosal areas of the face, arms, legs, or rectum, sometimes triggered by insect bites or other skin lesions. The skin picking varies in severity and may vary in the same patient over time. Anxiety, stress, or boredom seem to increase the severity of the picking behavior. Over half of adolescents and adults with PWS exhibit this self injurious behavior. Frequent nose bleeds or rectal bleeds should prompt further examination for sores from picking. Rectal ulcers may occur as a result of rectal itching or “digging.”

Treatment includes keeping the fingernails short, behavior modification, limiting the time spent in the bathroom to reduce opportunities for rectal picking, and providing substitute activities for the hands. Skin and mucosal infections can be managed with topical antibiotics, bandaging, and, if necessary, oral antibiotics. Oral topiramate has been shown to reduce skin picking in some cases. [Shapira: 2002]

The very obese individual is also more prone to fungal and bacterial infections, severe ulceration, and cellulitis, due to the inability to cleanse the skin in deep fat folds. Management includes daily cleansing in these folds and air drying with a heat lamp or hair dryer, and the use of medications for infections.

Subspecialist Collaborations and Other Resources

Pediatric Dermatology (see Services below for relevant providers)

May be helpful for those with more severe skin problems.

Pediatric Gastroenterology (see Services below for relevant providers)

If rectal picking continues, gastroenterology may be helpful to treat underlying conditions, such as constipation.

Cardiology

Cardiovascular risk is higher in individuals with PWS for a variety of reasons, including:
  • overeating and obesity,
  • poor dietary habits,
  • diabetes,
  • excess work of breathing, and
  • unexplained elevations of C-reactive protein in individuals with PWS.
These factors may result in hypertension, left ventricular hypertrophy, and right-sided heart failure, particularly in morbidly obese individuals. Although these are not generally present in young children with PWS, older individuals should be referred to a cardiologist for management as needed.

Subspecialist Collaborations and Other Resources

Pediatric Cardiology (see Services below for relevant providers)

Helpful in evaluating and managing cardiac risks.

Sleep

Apnea: Up to 90% of children and adults with PWS will have apnea and profound hypoventilation during sleep. [Butler: 2006] This may be due to extrinsic factors such as large tonsils and/or an intrinsic sleep disorder, probably related to hypothalamic dysfunction. Symptoms associated with the sleep disorder may include:
  • hypoventilation,
  • oxygen desaturation during REM sleep,
  • sleep apnea,
  • nocturnal enuresis, and
  • excessive daytime sleepiness and snoring.
If sleep evaluation finds apnea, consider referral to otolaryngology for evaluation of tonsils and adenoids and/or to a pulmonologist or sleep specialist to consider options such as BIPAP or CPAP.
Nocturnal enuresis may occur secondary to other underlying sleep problems or as an independent problem. If medical treatment is being considered, for example with DDAVP, start with smaller doses than those used in the general population and gradually increase the dose as needed.

Subspecialist Collaborations and Other Resources

Pediatric Pulmonology (see Services below for relevant providers)

For help in evaluating and managing persistent sleep problems.

Pediatric Otolaryngology (see Services below for relevant providers)

For evaluation and surgery for large adenoids or tonsils in those with obstructive sleep apnea.

Sleep Studies/Polysomnography (see Services below for relevant providers)

For help in evaluating and managing persistent sleep problems

Respiratory

Individuals with PWS may be at increased risk for respiratory problems, especially as infants. Problems at birth, due to hypotonia, weak chest muscles, and poor swallowing reflexes, may include asphyxia, apnea, respiratory failure, and hypoventilation.

Subspecialist Collaborations and Other Resources

Pediatric Pulmonology (see Services below for relevant providers)

For evluation and management of difficult respiratory problems.

Musculoskeletal

Individuals with PWS commonly have decreased muscle mass and strength. The few histologic and ultrastructural studies of muscle fibers performed in individuals with PWS have found only minimal abnormalities. A disuse or minimal myopathy may accompany central hypotonia in individuals with PWS. [Sone: 1994] Physical therapy and regular participation in exercise programs are essential in order to improve muscle strength and decrease fat mass. See the Motor Development in Children with Prader-Willi Syndrome Issue Page. Growth hormone therapy and testosterone therapy in adolescent and adult males also improve muscle strength in individuals with PWS.

Individuals with PWS may also present with scoliosis, kyphosis, and/or lordosis. Progression may occur with the increased linear growth during late childhood and adolescence. Treatment with growth hormone or anabolic steroids may exacerbate scoliosis. Scoliosis may compromise lung function and cause discomfort. Children with PWS should be screened regularly for scoliosis and, if scoliosis is present, referred to a pediatric orthopedic surgeon for management. Surgery to correct the scoliosis is sometimes necessary.

Hip dysplasia is observed in approximately 13% of individuals with PWS and should be screened for by the Medical Home provider with referral to an orthopedic surgeon if suspected. Hip ultrasound studies during infancy should be considered.

Osteoporosis is found in up to 50% of adolescents and adults with PWS [Kroonen: 2006] (see the Osteoporosis in Children with Prader-Willi Syndrome (Medical Home Portal) Issue Page) and should be considered in individuals with any fracture that is not consistent with the force of injury. If present, calcium and vitamin D intake should be maximized (see the Calcium and Vitamin D (general) Issue Page) and the provider should consider a referral to endocrinology. See also Osteoporosis in Individuals with PWS (PWSA USA).

See also Orthopedic Concerns in Children with PWS (PWSA).

Subspecialist Collaborations and Other Resources

Pediatric Orthopedics (see Services below for relevant providers)

Should be involved in the management of children PWS. Regular visits starting soon after diagnosis are helpful for screening and management of hip dysplasia, scoliosis/kyphosis, and orthopedic complications of obesity.

Physical Therapy (see Services below for relevant providers)

Regular visits are recommended to supervise conditioning and manage exercise in children with PWS.

Pediatric Endocrinology (see Services below for relevant providers)

To guide evaluation and treatment of osteoporosis.

Prader-Willi Clinics (see Services below for relevant providers)

When available, management at a PWS Clinic is preferred.

Eyes/Vision

Common visual problems in PWS include strabismus and myopia. Strabismus includes both esotropia, which is more common, and exotropia. Treatment may involve correction of refractive errors, patching of the better eye, and/or surgical correction of unbalanced eye muscles. Generally, treatment is more successful if started in the first few years of life. Amblyopia, or reduced vision due to disuse of an eye during development (commonly called "lazy eye"), results from inadequately treated strabismus.

Myopia (near-sightedness) and hyperopia (far-sightedness) are also common findings in children with PWS. Periodic screenings with a pediatric ophthalmologist are recommended throughout childhood.

Oculo-cutaneous albinism type 2 has been shown to be linked to the 15q11-q13 region - individuals with PWS due to a deletion in this area may also exhibit signs of depigmentation. Strabismus and impaired visual acuity may also be features of oculo-cutaneous albinism type 2. [Saadeh: 2007]

Subspecialist Collaborations and Other Resources

Pediatric Ophthalmology (see Services below for relevant providers)

Referrals to ophthalmology may be needed for management of strabismus and acuity problems beginning in early childhood.

Maturation/Sexual/Reproductive

Individuals with PWS typically have hypogonadotrophic hypogonadism, resulting in decreased estrogen levels in females and decreased testosterone levels in males. In the newborn period, most males have small testes and scrotum. Undescended testes are common in PWS. If the testes are not palpable, referral for a testicular ultrasound and evaluation by a pediatric urologist should be made by about 6 months of age. In newborn females, labial hypoplasia has been reported.

Over 80% of adolescents and adults with PWS will experience incomplete sexual maturation. Some children show early growth of underarm and pubic hair but then don't progress through puberty normally. Both sexes have good responses to treatment for hormone deficiencies, although side effects have been reported. Males with PWS typically don't progress past midpuberty and make no mature sperm. Testosterone levels are usually low and testosterone replacement beginning early in adolescence is often helpful. Normal levels of testosterone are needed to preserve bone mass and prevent osteoporosis. Testosterone replacement also increases muscle mass and strength. In older males with a small penis, a short course of testosterone can be given to improve appearance and size.

Most females with PWS do not have regular menstrual cycles and if they do menstruate, may have early menopause. Hypoplasia of the labia and/or clitoris in teenage females is common. The use of estrogen replacement therapy for women with PWS is not well established but may help preserve bone mass and reduce osteoporosis.

Fertility has only been documented in a few rare cases. Sexually active individuals should be counseled regarding the risk of pregnancy and the risk of having a child with PWS (50%, except when the mutation is due to maternal disomy).

Sexuality needs to be discussed with adolescents with disabilities and their parents in an effort to address common issues that may include:
  • the assumption that teens with disabilities do not need this information,
  • the lack of sex education specific to people with disabilities,
  • motor impairments that may make sexual function difficult, e.g., condom use,
  • the presence of intellectual impairment that might complicate the imparting and understanding of sex education material,
  • concerns about sexual exploitation in this population, and
  • body image concerns on the part of the adolescents.
See Sexuality and People with Disabilities(PDF Document 257 KB).

Subspecialist Collaborations and Other Resources

Pediatric Endocrinology (see Services below for relevant providers)

May be helpful for individuals with PWS with delayed puberty for consideration, initiation, and management of sex hormone therapy and for hypogonadism.

Gynecology (Ped/Adol, Special Needs) (see Services below for relevant providers)

To guide female patients with delayed puberty.

Pediatric Urology (see Services below for relevant providers)

For evaluation and management of males with crypto-orchidism and/or a small penis.

Dental

Referral to and regular follow-up by a dentist should be part of the overall treatment plan. However, providing preventive dental care may be difficult for the following reasons:
  • Cognitive and fine motor skills may limit the child's ability to perform brushing and flossing. Early emphasis on brushing and flossing is important.
  • Behavioral and health issues (e.g., sleep apnea, congenital heart disease) may increase the difficulty of dental visits and increase the risks of using sedation in the dental setting.
Children with PWS are prone to dental problems due to:
  • soft dental enamel making it easier for caries to develop. Special toothbrushes can be used that are less abrasive and help maintain the enamel and improve oral hygiene.
  • tendency to grind their teeth and because sugar intake may be large.
  • overproduction of saliva that results in thick, crusted deposits in the corners of the mouth and difficulty for the saliva to coat and protect the teeth. Products to increase and somewhat thin the saliva are available.
The primary care provider's role should include:
  • Discussing the need for routine dental care with families and ensuring that the child and family have been instructed on dental hygiene and fluoride supplementation. The CDC's page My Water's Fluoride provides information about fluoride levels in local water sources.
  • Helping families identify an appropriate dentist and/or funding. Dental check-ups are recommended by age 1 and then every 6 months.
  • Offering the family information about dental care specific to PWS. Ensure that families and dental care providers are aware of medical issues that may impact care (e.g., need for bacterial prophylaxis, sedation risks).
  • Monitoring general oral hygiene and dental health at well child visits and discussing issues with families as they arise. If signs of periodontal disease are evident, refer to a dental provider as-soon-as possible; periodontal disease can be rapidly progressive.
  • Helping the child, teen, and family manage halitosis, which may result in societal exclusion. It may improve with simple interventions such as tongue brushing, mouth washes, breath fresheners, and better dental hygiene or may require evaluation for medical issues, including chronic sinusitis, gastro-esophageal reflux, drooling, and periodontal disease.

Subspecialist Collaborations and Other Resources

Please consult your local dentist for input, recommendations, and follow-up for oral pathology and hygiene.

General Dentistry for Children (see Services below for relevant providers)

Particularly when pediatric dentists are not available.

Pediatric Dentistry (see Services below for relevant providers)

Often have special interest and skill in the care of children with special health care needs.

Development (general)

Language: Speech and language skills of individuals with PWS vary greatly, ranging from being nonverbal to having normal skills in adulthood. For children with PWS, the development of speech and language is often delayed, sometimes not combining words until they are six years of age. Problems are seen with speech rate, voice quality, and coordinating movements of the tongue, lips, jaws, and palate, leading to slow, slurred, and/or nasal speech. Most will have greater delays in expressive language, compared to receptive language. Difficulties with auditory short-term memory, order processing, and auditory verbal processing skills may affect vocabulary, grammar, and conversational abilities. Despite oral difficulties, children with PWS may show strengths in written language skills and reading, although reading comprehension may be poor. Speech and language difficulties continue into adolescence and adulthood. In these stages, emphasis should be placed on functional language skills and life-skills training. See Services below and the Normal Pattern of Speech Development (general) Issue Page for normal language milestones.

Sign language, picture communication boards, and augmentative communication devices should be considered for individuals with verbal communication problems. Referrals should be made as early as possible to speech and language pathologists. Aiding communication may help with behavior problems. See also the Augmentative Communication (general) Issue Page.

Subspecialist Collaborations and Other Resources

Speech/Language Therapy (see Services below for relevant providers)

In addition to speech/language therapy, speech therapists can initiate augmentative communication when needed.

Mental Health/Behavior

Behavioral issues often impact the child with PWS and their family more than any other aspect of the condition, though they are often due to other primary manifestations of the disorder. To avoid secondary behavioral issues, hyperphagia needs to be managed consistently by family, teachers, health care providers and anyone who interacts with the child. Controlling both the quantity and types of food that are available is essential. Attempts to suppress appetite with medication have been unsuccessful, but continue to be an active area of research. Conflicts related to food may lead to other behavioral problems. Aggressive behaviors or acting out can also be problematic.

Family support and anticipatory guidance for developmental delays and medical problems should be provided. Transitions and life changes are easier if the person with PWS is prepared for them, for example by allowing the child with PWS to visit a new school and meet his/her prospective teachers. Children with PWS should have a clear idea of expectations and the limits set for them, including those related to participation in social activities and interactions with other children.

Co-management with psychology and/or psychiatry may be important if simple measures are ineffective. The choice of psychotropic medication is the same as in typical patients with psychiatric diagnoses. Because many individuals with PWS may respond differently, dosing should start low and be titrated upward based on response.

Mood stabilizers have been used successfully for treating mood disorders and severe impulse control. Valproate and lithium are well tolerated at typical doses. Carbamazepine and oxcarbazepine should be used with care because of the increased risk for hyponatremia. Individuals with PWS will sometimes ingest large quantities of flavored beverages or water making them more susceptible to hyponatremia than non-PWS subjects.

Serotonin reuptake inhibitors have induced mood activation in some individuals with PWS causing worsening of behavioral problems or resulting in psychosis. The worsening behavior after an initial favorable response to medication may cause some physicians to increase the dose which further complicates treatment. However, when monitored closely, this class of medications can effectively treat OCD and depression in PWS individuals.

It is important to monitor all medications that may affect eating behavior and weight gain. In well-controlled environments, neuroleptics, atypical neuroleptics, valproic acid, and lithium have been used effectively without discernable change in food seeking behavior. [Forster: 2008] In severe cases, the child may need to be admitted to a facility that has experience in dealing with behavioral issues secondary to underlying medical problems.

Subspecialist Collaborations and Other Resources

Child Psychology (see Services below for relevant providers)

For help in managing the behavior problems of children with PWS and for family counseling.

Child Psychiatry (see Services below for relevant providers)

For help with severe behavior problems requiring medical treatment.

Learning/Education/Schools

Individuals with PWS typically have decreased cognitive functioning. IQ scores are generally in the range of mild to moderate intellectual disability (see the Intellectual disability/mental retardation module and Psychometric Testing (general)), although scores may range from normal to profound disability. The type of gene alteration causing the PWS plays a role in IQ score results - individuals with PWS due to uniparental disomy (UPD) have higher verbal than performance scores, while children with PWS due to deletions have higher performance scores. Children with UPD generally perform better than children with deletions and the size of the deletion correlates inversely with performance. Areas primarily affected include reading, spelling, and math. Short-term visual memory is often a weak area, whereas visual perception, organization, and puzzle solving are relative strengths. Children with PWS should have full psychological evaluations, including IQ and achievement, so that school and future planning can be optimized. An Individual Education Plan (IEP) should be initiated as early as possible. See Education & Schools. See also the Cognitive and Psychiatric Issues in Prader-Willi Syndrome Issue Page.

Attention deficit hyperactivity disorder (ADHD) should be treated if present. Co-management with a child psychiatrist may be indicated if medication is required.

Subspecialist Collaborations and Other Resources

Child Psychology (see Services below for relevant providers)

For help with educational programming and for behavior management programs.

Neuropsychology (see Services below for relevant providers)

For evaluationa and for help with educational programming.

Child Psychiatry (see Services below for relevant providers)

For medication management of ADHD if needed.

Family

Demands on families of children and adults with PWS are many. The Medical Home, in addition to providing support for the child, can work to ensure that needs are being met as well as possible. Emotional and financial support as well as information about and access to resources are important. Referral to the Prader-Willi Syndrome Association (USA) for information and support by other families, including meetings and Yahoo groups may be invaluable. State/local chapters of the Prader-Willi Syndrome Association may also be available, and be accessed through Prader-Willi Syndrome Association (USA). See Family support (PWSA USA) and Supplemental Security Income Guide for Children with PWS (PWSA USA) as well as Services, below.

Transitions

Transition from pediatric to adult life and health care systems can be challenging for individuals with PWS, their families, and their care providers. An important goal in transition planning is to find an acceptable Medical Home where the care provider recognizes the special needs of individuals with PWS and where a support team can be established that can communicate with the pediatric team. Other important goals of transition planning are to identify where the person will live and to identify educational and vocational training needs. Transition should include the following:
  • Planning should begin well before the patient will be transitioned.
  • Planning should take medical problems and learning disabilities into account.
  • Transition planning should be person- and family-centered and take into account cultural, ethnic, and spiritual values. Economic resources of the family need to be considered.
  • The overall goals of the youth should be considered. Goals for the future should include measurable outcomes. Transitions should be presented as positive changes in the person's life.
  • All members of the health care team, current and future, should agree on the overall plan and how to achieve the outcomes desired.
  • Medical management should be planned so there is no interruption in care and so that the patient and family are aware of potential changes in available resources. Medicaid support typically ends at age 19 and social security financial support after age 18.
  • Two key members of the transition team are a nutritionist who is familiar with the unique problems of the condition and past management plans and a social worker who can provide information about appropriate medical care and financial resources for adults.

See Services below.

Resources

Information & Support

Excellent resources, including those listed below, are available from the Prader-Willi Syndrome Association USA. Medical Home providers and families of children with PWS are encouraged to visit their web site and see the numerous resources available.

For Professionals

New Medical Alert Info (PWSA USA)(PDF Document 1.5 MB)
Twenty-page booklet listing factors that may complicate management of PWS or that could lead to severe medical complications; Prader-Willi Syndrome Association.

Supplemental Security Income Guide for Children with PWS (PWSA USA)
Frequently asked questions and downloadable documents for preparing a Supplemental Security Income (SSI) form; Prader; Willi Syndrome Association.

Orthopedic Concerns in Children with PWS (PWSA)
Discusses PWS issues related to care by the orthopedic surgeon.

Osteoporosis in Individuals with PWS (PWSA USA)

Central Adrenal Insufficiency (PWSA)
Brief discussion of screening recommendation for central adrenal insufficiency (CAI) in individuals with Prader-Willi syndrome; Willi Syndrome Association.

Postoperative Guidelines (PWSA USA)

Growth Hormone Consensus Statement (PWSA)(PDF Document 64 KB)
Current considerations regarding the use of GH treatment in PWS. Includes for those who have achieved final height; Prader-Willi Syndrome Association.

Recommendations for Evaluation of Breathing Abnormalities (PWSA)
Includes factors that increase risk of sleep disturbances and recommendations for diagnoses and management.

For Parents and Patients

Support

Prader-Willi Syndrome Association (USA)
A strong national organization of families and professionals, PSWA (USA) offers a toll-free helpline, a bimonthly newsletter and numerous publications about PWS, a World-Wide-Web page, and annual family conference and scientific meeting, and chapters throughout the country to provide local family support and advocacy.

General

Supplemental Security Income Guide for Children with PWS (PWSA USA)
Frequently asked questions and downloadable documents for preparing a Supplemental Security Income (SSI) form; Prader; Willi Syndrome Association.

Utah Prader-Willi Syndrome Association
Provides families and professionals with a network of support, resources, and information. Promotes awareness of PWS and raise funds that will directly benefit affected individuals in Utah.

Prader-Willi Syndrome Association (USA)
A strong national organization of families and professionals, PSWA (USA) offers a toll-free helpline, a bimonthly newsletter and numerous publications about PWS, a World-Wide-Web page, and annual family conference and scientific meeting, and chapters throughout the country to provide local family support and advocacy.

Food and Behavior in PWS (Pittsburgh Partnership)
Information for providers and families regarding food security and other aspects of behavior in individuals with PWS

Practice Guidelines

Goldstone AP, Holland AJ, Hauffa BP, Hokken-Koelega AC, Tauber M.
Recommendations for the diagnosis and management of Prader-Willi syndrome.
J Clin Endocrinol Metab. 2008;93(11):4183-97. PubMed abstract / Full Text
Based on published evidence-based data, unpublished data from personal experience, previous National and International PWS Conferences, and Prader-Willi Syndrome Association (USA) Clinical Advisory Groups. Written by an open international multidisciplinary expert group that met in 2006.

McCandless SE.
Clinical report—health supervision for children with Prader-Willi syndrome.
Pediatrics. 2011;127(1):195-204. PubMed abstract / Full Text
Designed to assist the pediatrician in caring for children with Prader-Willi syndrome diagnosed by clinical features and confirmed by molecular testing.

Tools

Bowel Management (general)(PDF Document 74 KB)
General information on bowel function and management of constipation for families and providers.

Bowel Management Algorithm(PDF Document 47 KB)
Algorithm for management of chronic constipation developed in collaboration with pediatric gastroenterology.

Constipation Evaluation Tool(PDF Document 84 KB)
Provides a format for evaluation of chronic constipation in children.

Growth Standards of Infants With Prader-Willi Syndrome (AAP)
Growth curves for weight, length, head circumference, weight/length, and BMI for non–growth hormone–treated white infants (boys and girls) with Prader-Willi syndrome (PWS) between 0 and 36 months of age.

Home Toileting Record(PDF Document 49 KB)
An easy-to-use form for keeping track of a child's toileting habits.

PWS Growth Charts(PDF Document 431 KB)
Growth charts for males and females (age 2 and up) with Prader-Willi syndrome including height, weight, and head circumference; reprinted with permission.

Services

Adaptive Recreation

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Assistive Technology

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Behavioral Programs

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Camps

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Child Psychiatry

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Child Psychology

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Disability Employment

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Early Intervention Programs

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Family Therapy

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General Dentistry for Children

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Group Homes

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Gynecology (Ped/Adol, Special Needs)

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Health Insurance/Funding, Transition

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Learning Evaluations

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Mental Health Clinics, Public

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Neuropsychology

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Nutrition/Dietary

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Occupational Therapy

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Pediatric Cardiology

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Pediatric Dentistry

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Pediatric Dermatology

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Pediatric Endocrinology

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Pediatric Gastroenterology

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Pediatric Genetics

Medical Genetics, more info...
100 N Mario Capecchi Drive
Salt Lake City, UT 84113
Phone: 801-231-3599
Fax: 801-585-7252
http://healthcare.utah.edu/pediatrics/Genetics/index.php

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Pediatric Ophthalmology

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Pediatric Orthopedics

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Pediatric Otolaryngology

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Pediatric Pulmonology

Pediatric Pulmonology, more info...
100 N Mario Capecchi Drive
Salt Lake City, UT 84133
Phone: 801-213-3599
http://healthcare.utah.edu/pediatrics/Pulmonary/index.php

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Pediatric Urology

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Physical Therapy

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Prader-Willi Clinics

Prader-Willi Syndrome Clinic , more info...
44 N Mario Capecchi Drive
Salt Lake City, UT 84114
Phone: 801-712-0501
Toll Free Phone: 800-829-8200
http://www.health.utah.gov/cshcn/index.html

Recreation Therapy

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SSI, Supplemental Security Income

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Sleep Studies/Polysomnography

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Social & Recreational Opportunities

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Social Work

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Speech/Language Therapy

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Vocational Education

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For other services related to this condition, browse our Services categories or search our database.

Studies

Angelman, Rett, and Prader Willi Syndromes Research Consortium
An integrated group of academic medical centers, patient support organizations, and clinical research resources dedicated to conducting clinical research in genetic and neurodevelopmental disorders and maintaining a Patient Contact Registry.

Helpful Articles

PubMed search on Prader-Willi syndrome: articles over the last 10 years

Butler MG, Lee PDK, Whitman, BY.
Management of Prader-Willi Syndrome.
3rd ed. New York, NY: Springer Verlag Inc.; 2006. 0387253971
Overview of the syndrome and natural history; diagnosis and genetics; medical physiology; and treatment and multidisciplinary management.

de Lind van Wijngaarden RF, Otten BJ, Festen DA, Joosten KF, de Jong FH, Sweep FC, Hokken-Koelega AC.
High prevalence of central adrenal insufficiency in patients with Prader-Willi syndrome.
J Clin Endocrinol Metab. 2008;93(5):1649-54. PubMed abstract / Full Text
Investigates whether PWS patients suffer from central adrenal insufficiency (CAI) during stressful conditions. Based data, recommends considering treatment with hydrocortisone during acute illness in PWS patients unless CAI has recently been ruled out with a metyrapone test.

Meaney FJ, Butler MG.
Craniofacial variation and growth in the Prader-Labhart-Willi syndrome.
Am J Phys Anthropol. 1987;74(4):459-64. PubMed abstract
A study of anthropometric variation and craniofacial growth in individuals with the Prader-Labhart-Willi syndrome (PLWS) illustrating the utility of anthropometry in clinical evaluation and research.

Butler MG, Hanchett JM, Thompson T.; Butler MG, Lee PDK, Whitman BY (eds.).
Clinical findings and natural history of Prader-Willi syndrome. In: Management of Prader-Willi Syndrome.
3rd ed. ed. New York: Springer Press; 2007.
This chapter in Management of Prader-Willi Syndrome presents an overview of natural history and clinical findings in PWS.

Cassidy SB, Driscoll DJ.
Prader-Willi syndrome.
Eur J Hum Genet. 2009;17(1):3-13. PubMed abstract / Full Text
Clinical overview of diagnostic and management information with charts and photos.

Schrander-Stumpel CT, Sinnema M, van den Hout L, Maaskant MA, van Schrojenstein Lantman-de Valk HM, Wagemans A, Schrander JJ, Curfs LM.
Healthcare transition in persons with intellectual disabilities: general issues, the Maastricht model, and Prader-Willi syndrome.
Am J Med Genet C Semin Med Genet. 2007;145C(3):241-7. PubMed abstract / Full Text
Discusses the aging and transition process for those with PWS.

Butler MG.
Prader-Willi syndrome: current understanding of cause and diagnosis.
Am J Med Genet. 1990;35(3):319-32. PubMed abstract
Reviews of current understanding of the major clinical, cytogenetic, and DNA findings. Summarizes from literature clinical manifestations and cytogenetic abnormalities.

Authors

Contributing Authors: Mary Riske, RN, MS - 8/2008
Robin Troxell, MS, CGC - 8/2008
Ralph Vogel, PhD, RN - 8/2008
Reviewing Authors: Alan Rope, MD - 11/2008
Kyna Byerly, MS, CGC - 8/2008
Content Last Updated: 1/2011

Funding/Support

This module was developed in partnership with the Heartland Regional Genetics and Newborn Screening Collaborative Heartland Regional Genetics and Newborn Screening Collaborative and was funded in part by a Health Resources Services Administration (HRSA) cooperative agreement (U22MC03962).

We appreciate the Prader-Willi Syndrome Association (USA) for their outstanding support of individuals with PWS and their families and for the information they provide on their website – www.pwsausa.org – to which we have provided several links within the Diagnosis Module.

Page Bibliography

Alexander RC, Greenswag LR, Nowak AJ.
Rumination and vomiting in Prader-Willi syndrome.
Am J Med Genet. 1987;28(4):889-95. PubMed abstract
A study that includes those with Prader-Willi who also experience more unusual symptoms of rumination and vomiting.

Butler MG.
Management of obesity in Prader-Willi syndrome.
Nat Clin Pract Endocrinol Metab. 2006;2(11):592-3. PubMed abstract / Full Text
Discusses pros and cons of various ways to treat obesity in Prader-Willi syndrome.

Butler MG, Meaney FJ.
Standards for selected anthropometric measurements in Prader-Willi syndrome.
Pediatrics. 1991;88(4):853-60. PubMed abstract
Standards that can be used with the examination of patients who have Prader-Willi syndrome and in the comparison of the patient who has Prader-Willi syndrome with other similarly affected individuals. The standards may also be useful for assisting in the diagnosis of Prader-Willi syndrome, particularly in younger individuals.

Festen DA, de Weerd AW, van den Bossche RA, Joosten K, Hoeve H, Hokken-Koelega AC.
Sleep-related breathing disorders in prepubertal children with Prader-Willi syndrome and effects of growth hormone treatment.
J Clin Endocrinol Metab. 2006;91(12):4911-5. PubMed abstract
A study showing GH treatment does not aggravate the sleep-related breathing disorders in young PWS children and that monitoring during upper respiratory tract infection in PWS children should be considered.

Forster, JL, and Gourash, LM.
Managing Prader-Willi Syndrome: A Primer for Psychiatrists .
2008; MD Pittsburgh Partnership Printed by Prader-Willi Syndrome Association USA ; http://www.pwsausa.org/syndrome/psychiatrists%20primer%20for%20pws.pdf
Discusses five domains of behavioral symptoms, and psychiatric evaluation, management, co-morbidity, and food security.

Goldberg DL, Garrett CL, Van Riper C, Warzak WJ.
Coping with Prader-Willi syndrome.
J Am Diet Assoc. 2002;102(4):537-42. PubMed abstract
Includes basic behavior-management strategies, including successful use of incentives, responding to misbehavior, rewarding compliance with an exercise program, and modifying the behavior management when indicated.

Grugni G, Crinò A, Bosio L, Corrias A, Cuttini M, De Toni T, Di Battista E, Franzese A, Gargantini L, Greggio N, Iughetti L, Livieri C, Naselli A, Pagano C, Pozzan G, Ragusa L, Salvatoni A, Trifirò G, Beccaria L, Bellizzi M, Bellone J, Brunani A, Cappa M, Caselli G, Cerioni V, Delvecchio M, Giardino D, Iannì F, Memo L, Pilotta A, Pomara C, Radetti G, Sacco M, Sanzari A, Sartorio A, Tonini G, Vettor R, Zaglia F, Chiumello G.
Italian National Survey for Prader-Willi syndrome: an epidemiologic study.
Am J Med Genet A. 2008;146(7):861-72. PubMed abstract
A study that attempted to gather information about all people with genetically confirmed diagnosis of PWS living in Italy.

Haqq AM, Stadler DD, Jackson RH, Rosenfeld RG, Purnell JQ, LaFranchi SH.
Effects of growth hormone on pulmonary function, sleep quality, behavior, cognition, growth velocity, body composition, and resting energy expenditure in Prader-Willi syndrome.
J Clin Endocrinol Metab. 2003;88(5):2206-12. PubMed abstract
Contains results of a study on the effects of GH administration on pulmonary function, sleep, behavior, cognition, linear growth velocity, body composition, and resting energy expenditure (REE) in children with Prader-Willi syndrome.

Holm VA, Pipes PL.
Food and children with Prader-Willi syndrome.
Am J Dis Child. 1976;130(10):1063-7. PubMed abstract
Illustrates successes in preventing excessive weight gain in children with PW when caretakers receive appropriate counseling on how to provide low-calorie food and how to make other food inaccessible.

Kroonen LT, Herman M, Pizzutillo PD, Macewen GD.
Prader-Willi Syndrome: clinical concerns for the orthopaedic surgeon.
J Pediatr Orthop. 2006;26(5):673-9. PubMed abstract
Cites osteopenia, poor impulse control and defiant behaviors, and diminished pain sensitivity as aspects of PWS that may complicate all facets of orthopaedic nonsurgical and surgical management in this patient population.

Miller J, Silverstein J, Shuster J, Driscoll DJ, Wagner M.
Short-term effects of growth hormone on sleep abnormalities in Prader-Willi syndrome.
J Clin Endocrinol Metab. 2006;91(2):413-7. PubMed abstract
A study that concludes that most PWS patients had improvement after short-term GH treatment, but 32% had worsening of sleep disturbance. A subset of PWS patients are at risk during this window of vulnerability shortly after initiation of GH.

Saadeh R, Lisi EC, Batista DA, McIntosh I, Hoover-Fong JE.
Albinism and developmental delay: the need to test for 15q11-q13 deletion.
Pediatr Neurol. 2007;37(4):299-302. PubMed abstract / Full Text
Reports that Phenotypic features of Angelman syndrome or Prader-Willi syndrome in a patient with albinism should prompt further gene testing.

Scheimann AO, Butler MG, Gourash L, Cuffari C, Klish W.
Critical analysis of bariatric procedures in Prader-Willi syndrome.
J Pediatr Gastroenterol Nutr. 2008;46(1):80-3. PubMed abstract
Various bariatric procedures have been used to cause gastric stasis, decrease gastric volume, and induce malabsorption, with poor results in PWS patients in comparison with normal obese individuals.

Shapira NA, Lessig MC, Murphy TK, Driscoll DJ, Goodman WK.
Topiramate attenuates self-injurious behaviour in Prader-Willi Syndrome.
Int J Neuropsychopharmacol. 2002;5(2):141-5. PubMed abstract
Report attenuation of SIB with resultant lesion healing in three PWS adults treated with topiramate in an 8-wk open-label trial - suggest more study is needed.

Sone S.
Muscle histochemistry in the Prader-Willi syndrome.
Brain Dev. 1994;16(3):183-8. PubMed abstract
Although muscle hypotonia in PWS has been thought to be due to central nervous system abnormality, findings suggest that primary muscle pathology, including muscle fiber immaturity and abnormal muscle fiber type distribution, at least in part, plays a role in muscle hypotonia and weakness.

Stevenson DA, Anaya TM, Clayton-Smith J, Hall BD, Van Allen MI, Zori RT, Zackai EH, Frank G, Clericuzio CL.
Unexpected death and critical illness in Prader-Willi syndrome: report of ten individuals.
Am J Med Genet A. 2004;124A(2):158-64. PubMed abstract
Suggests that increased risk for critical illness be considered in the discussion of anticipatory guidance for the care of infants with PWS. Data showed that under the age of 2 years, childhood illnesses in general were associated with high fever and rapid demise or near-demise.

Tauber M, Diene G, Molinas C, Hébert M.
Review of 64 cases of death in children with Prader-Willi syndrome (PWS).
Am J Med Genet A. 2008;146(7):881-7. PubMed abstract
Results show that respiratory insufficiency or infections were the most common cause of death which were reported in 61% of the children (68% in GH-treated and 55.5% in -untreated patients). The first 9 months of GH treatment seems to be a high-risk period emphasizing the need for comprehensive care before and during GH treatment.

Wilson TA, Rose SR, Cohen P, Rogol AD, Backeljauw P, Brown R, Hardin DS, Kemp SF, Lawson M, Radovick S, Rosenthal SM, Silverman L, Speiser P.
Update of guidelines for the use of growth hormone in children: the Lawson Wilkins Pediatric Endocrinology Society Drug and Therapeutics Committee.
J Pediatr. 2003;143(4):415-21. PubMed abstract
Includes advantages, side effects, and cautions for using growth hormones to stimulate linear growth and improve body composition in children with GHD and to increase linear growth in children with chronic renal failure, Turner syndrome, PWS, and those with postnatal growth failure secondary to having been born SGA.

de Lind van Wijngaarden RF, Otten BJ, Festen DA, Joosten KF, de Jong FH, Sweep FC, Hokken-Koelega AC.
High prevalence of central adrenal insufficiency in patients with Prader-Willi syndrome.
J Clin Endocrinol Metab. 2008;93(5):1649-54. PubMed abstract / Full Text
Investigates whether PWS patients suffer from central adrenal insufficiency (CAI) during stressful conditions. Based data, recommends considering treatment with hydrocortisone during acute illness in PWS patients unless CAI has recently been ruled out with a metyrapone test.