Medical considerations in prader-willi syndrome

In the decade since the previous edition of this text,2 a wealth of information has accumulated regarding the medical pathophysiology and treatment of PWS. Clinical diagnostic criteria and acceptance of genetic testing in the mid-1990s helped to focus clinical and research attention on individuals with this condition. The identifi cation of a defect in the growth hormone (GH) system and, moreover, demonstration of GH treatment effi cacy, provided the fi rst and, to date, only treatment for PWS to attain regulatory approval. Despite these advances, we still lack systematic information regarding many of the morbidities associated with PWS. Aside from GHrelated studies, few rigorously-collected data on suffi cient numbers of individuals have been published. Medical care for most individuals with PWS worldwide remains uncoordinated and clinical protocols are largely based on anecdotal experience. These circumstances are undoubtedly due to a combination of the uncommon occurrence of the condition, a relative paucity of specialized treatment facilities with consequent lack of centralized care and data collection, and historical prejudices and beliefs regarding natural history and treatment outcomes. Nevertheless, our understanding of the medical aspects of PWS has reached a new level in the past decade, and there are continuing efforts amongst experts in the fi eld to establish logical, evidence-based treatment modalities. Whereas the 1995 edition of this text contained only a single chapter concerning medical pathophysiology, entitled 'Endocrine and Metabolic Aspects of Prader-Willi Syndrome,'127 the current edition includes three chapters covering a wider range of medical concerns. This fi rst chapter in Part II provides a general overview of medical concerns in PWS and discussion of conditions that are not addressed in successive chapters. The next chapter (Chapter 6) addresses issues related to obesity, gastrointestinal function, and body composition. Finally, Chapter 7 is dedicated to a review of GH therapy in PWS.