Background: Prader-Willi syndrome (PWS) is the most common genetic obesity. Excessive weight gain follows failure-to-thrive in early infancy; in adolescents and young adults, excess body weight can exceed 100%. The hyperphagia associated with PWS is responsible for the early mortality. Dietary restriction, alone or combined with anorexic drugs, are ineffective to induce a permanent weight loss. Thus, surgical treatment of morbid obesity in PWS has been attempted, but gastric restrictive operations are unable to produce stable weight loss. In a small number of patients, favorable results have been reported with biliopancreatic diversion (BPD).
Case report: A 24-year-old woman with PWS, Pickwickian, at age 21 weighed 80 kg (BMI= 50) and underwent BPD.
Results: 3 years after the BPD she regained 21 of the 26 kg lost; somnolence and respiratory difficulties were the same as before surgery. The patient now presents severe reduction of bone mass density, hypochromic anemia, hypoproteinemia, and diarrhea associated with eating.
Conclusion: The regain of weight following BPD suggests that this procedure alone is not adequate for long-term control of obesity in PWS.