[Atopic dermatitis. Epidemiology].

It was in 1923 that Coca and Cooke made a distinctive entity of a group of diseases of allergy, including asthma, and hay fever. They remarked that these affections were frequently associated and/or preceded by eczema localised to certain regions (flexor folds), sometimes generalised, perhaps appearing suddenly, from the third month in infants. In effect, the majority of constitutional eczema is in infants of 6 months, 75% of the cases are in one-year-old children. There is recovery in 5 years following the start of the affection in 90% of cases. Only 5% of cases persist to adulthood.