The epidemiology of immune thrombocytopenic purpura.

PURPOSE OF REVIEW: This review updates the American Society of Hematology and British guidelines on immune thrombocytopenic purpura incidence, prevalence, and natural history, with recent observations from the peer-reviewed medical literature.

RECENT FINDINGS: This analysis was conducted using literature-indexing systems to identify relevant articles. Information about the incidence and prevalence of immune thrombocytopenic purpura is limited, with nearly all data coming from Europe. Recent reports have confirmed earlier studies suggesting that the disease occurs in five out of 100,000 children per year, and that spontaneous recovery is typical. Intracranial hemorrhage occurs in 0.5-1.0% of affected children, and half are fatal. The incidence in adults is roughly two in 100,000 per year and may be more common in older adults than previously recognized. A female predominance occurs only among middle-aged patients, and there is no racial variation in incidence. Spontaneous remission rates vary by report and range from 5 to 11%.

SUMMARY: Spontaneous remission occurs more frequently in children than in adults, and intracranial bleeding is uncommon. The incidence increases with age, with a female predominance only among middle-aged adults. Adult patients with chronic disease may have a better prognosis than previously recognized, although only a small minority recover spontaneously.