TENTATIVE CLASSIFICATION OF NEUROPSYCHIATRIC DISTURBANCES IN PRADER-WILLI-SYNDROME

Prader-Willi syndrome presents behavioural characteristics at the temp eramental level which can be described as oppositional, explosive and at times antisocial. These traits may fluctuate and be driven by unkno wn biological factors as well environmental variables. Obsessive compu lsive traits and other anxiety symptoms are also frequent. Delusional psychotic thinking is manifest in some cases, but may be latent in sev eral such patients. A third set of manifestations is a 'refusal-lethar gy' syndrome of akinesis, refusal of food and drink, and soiling, whic h seems to be triggered by environmental circumstances but resembles t he hypersomnic, lethargic depressions. These three sets of phenomena a re documented through the clinical observation of nine cases and may b e useful in the study of the genotype-phenotype relationship in this a nd other syndromes, particularly those in which similar manifestations are observed and cyclic changes are seen. The use of drugs in this sy ndrome can also become more rational if this classification is used to identify clearer targets for treatment. The possibility that most man ifestations of the syndrome may be an expression of a hyposerotonergic defect is suggested.