Chronic idiopathic thrombocytopenic purpura: incidence, treatment, and outcome.

In order to determine incidence, outcome, trends in management and natural history, data on 92 children with chronic idiopathic thrombocytopenic purpura (ITP), comprising 66 from a single centre's experience between 1950 and 1980 and all 26 presenting from a defined population between 1984 and 1994, have been analysed. Its incidence, calculated from the population based group, is 0.46/10(5) children per year. Twenty nine of 34 (85%) remitted after splenectomy. Short initial histories predicted response to splenectomy. Splenectomy was offered only half as frequently in the last 10 years as in the 30 year, single centre group of children. Most (39 cases) of those not offered or successfully treated by splenectomy recovered spontaneously. The predicted spontaneous remission rate in 85 with adequate follow up data is 61% after 15 years. No other form of active treatment was of lasting benefit. No death solely attributable to chronic ITP occurred. The high spontaneous recovery rate, low mortality, and generally benign outcome may encourage a less interventionist approach to management.