Prader Willi Syndrome
“Prader-Willi syndrome is a rare disorder present at birth that results in a number of physical, mental and behavioral problems. A key feature of Prader-Willi (prah-dur VIL-ee) syndrome is a constant sense of hunger that usually begins after the first year of life. People with Prader-Willi syndrome want to eat constantly and usually have trouble controlling their weight. Many complications of Prader-Willi syndrome are due to obesity. If your child has Prader-Willi syndrome, a team of specialists can work with you to manage your child's symptoms and reduce the risk of developing complications.” (Mayo Clinic Staff, 01 May 2013, page 1).
“Prader-Willi syndrome is caused by a gene missing on part of chromosome 15. Normally, your parents each pass down a copy of this chromosome. Most patients with Prader-Willi syndrome are missing the genetic material on part of the father's chromosome. The rest of patients with this condition often have two copies of the mother's chromosome 15. The genetic changes occur randomly. Patients usually do not have a family history of the condition.” (Cooke DW, Divall SA, Radovick S, 07 May 2012, para. 2)
“Metabolism is a term that is used to describe all chemical reactions involved in maintaining the living state of the cells and the organism. Metabolism can be conveniently divided into two categories: * Catabolism - the breakdown of molecules to obtain energy * Anabolism - the synthesis of all compounds needed by the cells
Metabolism is closely linked to nutrition and the availability of nutrients. Bioenergetics is a term which describes the biochemical or metabolic pathways by which the cell ultimately obtains energy. Energy formation is one of the vital components of metabolism.” (Mandal, Ananya, MD, 03 April 2014, para. 1)
“Signs and symptoms of Prader-Willi syndrome generally occur in two stages. Signs of the disorder that may be present in the first year of life include:
Poor muscle tone, 1a primary sign of Prader-Willi syndrome during infancy is poor muscle tone (hypotonia). Babies may rest with their elbows and knees loosely extended instead of fixed, and they may feel floppy or like "rag dolls" when they're held.
Distinct facial features, children with Prader-Willi syndrome may be born with almond-shaped eyes, a narrowing of the head at the temples, a turned-down mouth and a thin upper lip.
Failure to thrive, during the first year of life, children with Prader-Willi syndrome may have a poor sucking reflex due to decreased muscle tone. Because poor sucking makes feeding difficult, they tend to gain weight slowly.
Lack of eye coordination (strabismus), the eyes of a child with Prader-Willi syndrome may not move together. Therefore, they may cross or wander to the side.
Generally poor responsiveness, a baby may seem unusually tired, respond poorly to stimulation, wake with difficulty or have a weak cry.” (Mayo Clinic Staff, 01 May 2013, page 2). “From about ages 1 to 4, other signs of Prader-Willi appear. These problems will remain present throughout life and require careful management or treatment. These signs may include:
Food craving and weight gain, the classic signs of the disorder are a constant craving for food and a rapid gain in weight. Because a child with Prader-Willi syndrome is always hungry, he or she eats frequently and consumes large portions. A child may develop unusual food-seeking behaviors, such as hoarding food or eating things such as garbage or frozen food.
Underdeveloped sex organs, a condition called hypogonadism occurs when sex organs — the testes in men and the ovaries in women — produce little or no sex hormones. This results in underdeveloped sex organs, incomplete development at puberty and in nearly all cases infertility. Women may not start menstruating until their 30s, or they may never menstruate. Men may not have much facial hair, and their voices may never fully deepen.
Poor growth and physical development, children with Prader-Willi syndrome have low muscle mass. They may have short hands and feet. When a person with the disorder reaches full adult stature, he or she is usually shorter than other family members.
Learning disabilities, mild to moderate cognitive impairment is a common feature of the disorder. Essentially all people with Prader-Willi syndrome, even those without significant cognitive disability, have some learning disabilities.
Delayed motor developments, toddlers with Prader-Willi syndrome often reach milestones in physical movement later than do other children. Sitting up by oneself may be delayed until 12 months and walking until 24 months.
Speech problems, often delayed until a child is 2 years of age. Poor articulation of words may be an ongoing problem.
Behavioral problems, children may at times be very stubborn or throw temper tantrums, especially when denied food. They may also develop obsessive-compulsive disorder, which results in unwanted, recurring thoughts or repetitive behaviors, or both. Other mental health disorders, such as skin picking or rectal gouging, may develop.
Sleep disorders, some children with Prader-Willi syndrome may have sleep disorders, including disruptions of the normal sleep cycle and sleep apnea, a condition in which breathing pauses during sleep. Obesity may worsen sleep disorders.” (Mayo Clinic Staff, 01 May 2013, page 2). “Prader-Willi syndrome, which occurs in about one in every 15,000 to 25,000 live births, is the most common genetic disorder that can lead to life-threatening obesity in children. Boys and girls are equally affected. Scientists do not know what increases the risk for Prader-Willi syndrome. The genetic error that leads to Prader-Willi syndrome occurs at random, usually around the time of conception or during early fetal development. The syndrome is usually not hereditary. Genetic testing can identify the chance that a second sibling will develop Prader-Willi syndrome, a possibility that is usually less than 1%.” (Scheimann, 08 June 2011, para. 1).
“Obesity is the greatest threat to health. Limiting calories will control the obesity, but the family, neighbors, and school must work together closely because the child will try to get food wherever possible. Exercise can increase lean body mass in children with Prader-Willi syndrome. Growth hormone is approved by the Food and Drug Administration for the treatment of Prader-Willi syndrome. It can help: Improve physical strength and agility, Improve height, Increase lean muscle mass and decrease body fat, Improve weight distribution, Increase stamina, Increase bone mineral density. There have been some concerns that taking growth hormone therapy may lead to sleep apnea. A child who takes hormone therapy needs to have annual sleep studies to monitor for sleep apnea. Low levels of sex hormones may be corrected at puberty with hormone replacement.” (Mandal, Ananya, MD, 03 April 2014, para. 5).
“The child will need the right education for his or her IQ level. The child will also need speech, physical, and occupational therapy as early as possible. Controlling weight will allow for a much more comfortable and healthy life.” (Mandal, Ananya, MD, 03 April 2014, para. 7).

Reference
Cooke DW, Divall SA, Radovick S. Normal and aberrant growth. In: Melmed S, ed. Williams Textbook of Endocrinology. 12th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 24. Retrieved from http://www.ncbi.nim.gov/pubmedhealth/PMH0002572
Mandal, A., (2014, April 3). What is Metabolism. Retrieved from http://www.news-medical.net/health/what-is-metabolism.aspx
Mayo Clinic Staff. (2013, May 1). Prader-Willi Syndrome. Retrieved from http://www.mayoclinic.org/diseases-conditions/prader-willi-syndrome/basics/
McCandless, S. E.; Committee on Genetics. (2010). Clinical report-health supervision for children with Prader-Willi syndrome. Pediatrics, 127, 195-204. Retrieved from http://www.nichd.nih.gov/health/topics/prader-willi/conditioninfo/Pages/at-risk.aspx
Scheimann, A. (2011, June 8). Prader-Willi Syndrome. Medscape Reference. Retrieved July 17, 2012, from http://emedicine.medscape.com/article/947954-overview#a0199