An Adult with Prader-Willi Syndrome andAnorexia Nervosa: A Case Report

Debra Counts*

Department of Pediatrics, University of Maryland School of Medicine,Baltimore, Maryland

Accepted 29 August 2000

Abstract: A 39-year-old man with Prader-Willi syndrome presents for evaluation of uncon-trolled weight loss. Past history was significant for gastric bypass and prior episodes ofintentional dieting. Family history was significant for an alcoholic father and two siblings withanorexia nervosa. The patient was unconcerned about his weight loss despite cachexia anddid not want to stop dieting. This presentation of a restrictive eating pattern in a man with asyndrome usually associated with compulsive hyperphagia is the first known report. © 2001by John Wiley & Sons, Inc. Int J Eat Disord 30: 231–233, 2001.

Key words: Prader-Willi syndrome; gastric bypass; compulsive hyperphagia

INTRODUCTION

Prader-Willi Syndrome (PWS) is the constellation of cognitive delay, hypotonia ininfancy, hypogonadism, short stature, and hyperphagia leading to obesity as originallydescribed by Prader, Labhart, Willi, and Fanconi (1956) and diagnostic criteria presentedby Holm et al. (1993). The syndrome is caused by an abnormality of 15q-, usually due touniparental disomy. In infancy, there is usually poor feeding due to the hypotonia, but thehyperphagia begins between the ages of 2 and 3 years. Children with PWS have a lowercaloric need than age-matched peers due to their lower muscle mass, and therefore lowermetabolic need. Unless an intervention to prevent weight gain due to hyperphagia ismade, most of these children develop morbid obesity, as well as the multiple complica-tions of obesity (e.g., diabetes, dyslipidemia, hypertension, and orthopedic problems).

CASE REPORT

A 39-year-old man with PWS presented for evaluation of severe weight loss. His motherreported that 9 months prior to presentation, he weighed 66.8 kg (body mass index [BMI]= 27.8 kg/m2). He began the Atkins diet (very low carbohydrate intake) and lost weight

*Correspondence to: Debra Counts, M.D., UMMS, 22 S. Greene St., Rm N5E13, Baltimore, MD 21201.

© 2001 by John Wiley & Sons, Inc.

Prod. #1672

steadily. He had gastric bypass surgery at age 11 years. Since then, he has had immediatestooling after any oral intake. Because he is employed, he does not eat or drink all day. Hehas a single meal in the evening. Past medical history is significant for poor feeding andhypotonia as an infant, massive obesity and cognitive delay as a child, and the diagnosisof PWS at age 10 years when he weighed 88.6 kg. His mother reports that he had similarepisodes of intentional dieting for weight control with weight loss at age 20 and 30 years,but these did not result in sustained weight loss to the point of cachexia. Family historyis significant for alcoholism in the father and anorexia nervosa in two female siblings.Review of systems was significant for skin picking.

Regarding social history, he has had the same full-time job for 13 years and he livesindependently with part-time assistance from family. On direct interview with the pa-tient, he was unconcerned about the large weight loss, did not feel he was too thin, anddid not believe it was necessary to amend his eating habits.

On physical exam, he was a small, cachectic man who was pleasant and quiet. Heightwas equivalent to age 13 years = 155 cm (<5th percentile); weight 41.8 kg (BMI = 17.4kg/m2). His hands and feet were small, and he had a large abdominal scar. Pubic hair wasTanner IV and testes were 15 ml.

Diagnostic tests (complete blood count [CBC], electrolytes, chemistries, T4, and lipids)were normal. Urine was positive for small ketones and negative for glucose. The valuesfor insulin-like growth factor-1 (IGF-1) and testosterone were 44 ng/ml (114–492) and 147ng/dl (241–827), respectively. Abdominal computed tomography (CT) scan showed thegastric bypass anatomy with some thickening of the intestinal wall.

The patient and mother received counseling from a nutritionist and behavioral psy-chologist on appropriate nutrition. Two weeks later, he continued to lose weight and toeat low-calorie foods while avoiding high-calorie foods. The patient was referred to a daytreatment center for management of his eating disorder.

DISCUSSION

To the author’s knowledge, this is the first report of a patient with PWS presenting witha restrictive eating disorder. The typical behavior in patients with PWS is uncontrolledeating, due to an impaired satiety response (Holland, Treasure, Coskeran, & Dallow,1995). This patient does exhibit the obsessive behavior found in people with PWS. How-ever, it is manifested as a food restriction. This patient is likely to have additional pre-disposition for a restrictive eating disorder, either environmental or genetic, because hehas two affected siblings. Bartolucci and Younger (1994) described three types of neuro-psychiatric disturbances in patients with PWS: behavioral problems (oppositional, explo-sive, and anti-social), delusional psychotic thinking, and a “refusal-lethargy” syndrome(akinesis, food and drink refusal, and soiling). This patient’s behavior does not fit therefusal-lethargy syndrome because he is otherwise able to function and to go to workdaily. The anorexia nervosa in this patient is an unusual manifestation of obsessive be-havior in PWS.

REFERENCES

Bartolucci, G., & Younger, J. (1994). Tentative classification of neuropsychiatric disturbances in Prader-Willisyndrome. Journal of Intellectual Disability Research, 38 (Pt. 6), 621–629.

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Holland, A.J., Treasure, J., Coskeran, P., & Dallow, J. (1995). Characteristics of the eating disorder in Prader-Willi syndrome: Implications for treatment. Journal of Intellectual Disability Research, 39 (Pt. 5),373–381.

Holm, V.A., Cassidy, S.B., Butler, M.G., Hanchett, J.M., Greenswag, L.R., Whitman, B.Y., & Greenberg, F. (1993).Prader-Willi syndrome: Consensus diagnostic criteria. Pediatrics, 91, 398–402.

Prader, A., Labhart, A., Willi, H., & Fanconi, G. (1956). Ein Syndrome von Adipostas, Kleinwuchs, Kryptorchis-mus, und Idiote bei Kindern und Erwachsenen, die als Neugeborene ein myatonie-artiges Bild gebotenhaben. [A Syndrome of Adiposity, short stature, cryptorchidism, and mental retardation in children andadults who as newborns presented with myotonia]. Proceedings of the VIII International Congress onPediatrics, Copenhagen.

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