ABSTRACT
In 1966, Andreas Rett, an Austrian pediatrician in Vienna, first described a peculiar disorder in girls characterized by global deceleration of psychomotor development and subsequent loss of acquired cognitive and motor skills, occurring after 6-18months of apparently normal development (1). However, the condition was not brought to the attention of the English-speaking world (clinicians and researchers worldwide) until 1983, when Hagberg and his colleagues described 35 patients, all girls from three different countries (France, Portugal, and Sweden), with a uniform and striking, progressive encephalopathy. After development up to the age of 6-18months, developmental stagnation occurs, followed by rapid deterioration of higher brain functions. Within the
following 1.5 years, this deterioration progresses to severe dementia with loss of speech, autistic features (poor eye contact, lack of sustained interest, speech disturbances, and repetitive truncal rocking), loss of purposeful use of the hands (repetitive, purposeless, usually midline, and stereotypic hand movements) (Fig. 1), jerky truncal ataxia, postnatal microcephaly, and also irregular breathing while awake, with hyperventilation. Thereafter, there is a period of apparent stability lasting for decades. However, profound mental retardation persists, with marked motor dysfunction and jerky truncal
ataxia. Additional neurologic abnormalities intervene insidiously, mainly spastic paraparesis, vasomotor disturbances of the lower limbs, and epilepsy. Scoliosis is also very common, and the feet may be trophic and cyanotic. Emotional contact tends to improve with age (2).
