Serious behavioural problems in mentally handicapped children: the Smith-Magenis syndrome
background The Smith-Magenis syndrome is a genetically determined syndrome that is characterised primarily by unusual behaviour. The syndrome is still insufficiently recognised although it has an incidence of 1:25,000, which is just as high as that of the Prader-Willi syndrome and the Williams syndrome.
aim To make the syndrome better known among professionals by briefly summarising the cause, the most important physical manifestations and the cognitive profile and by describing the unusual behavioural pattern associated with the syndrome. Attention will also be given to therapeutic aspects. method The relevant literature was traced via the PubMed database using the search terms 'Smith-Magenis syndrome' and 'deletion 17p11.2'. No exclusion criteria were used.
results The literature search in PubMed and through cross-references yielded 52 articles with clinical descriptions of the Smith-Magenis syndrome.
conclusion The Smith-Magenis syndrome is a genetically determined syndrome characterised by moderately severe mental retardation (average iq between 40 and 55), unusual facial features (broad face, deep-set eyes, flat middle third of face, broad mouth with down turned corners and prominent chin) and especially by behavioural problems: low frustration tolerance, sudden mood swings and excessive irritability. Highly characteristic behaviour of children with the Smith-Magenis syndrome includes self-hugging, polyembolokoilomania (insertion of objects into body cavities), onychotillomania (pulling out finger- and toenails) and sleep disturbances.