Adult idiopathic thrombocytopenic purpura (ITP)--a prospective tracking of its natural history.

Thirty-seven Asian patients (30 women, 7 men) with chronic idiopathic thrombocytopenic purpura (ITP) followed prospectively for 4 to 15 years showed a highly variable clinical course. The women as a group had a much lower initial platelet count than the men (28 x 10(9)/l versus 54 x 10(9)/l). All the women but only 2 men required treatment for symptomatic thrombocytopenia. Six women developed secondary autoimmune disorders (4 systemic lupus erythematosus and 2 Evan's syndrome) after 14 to 33 months of clinical follow up. Although their responses to corticosteroid therapy were suboptimal when initiated for ITP, these 6 patients uniformly demonstrated a complete platelet response when corticosteroid treatment was re-introduced following the evolution of secondary autoimmune disorders. Four of the 5 untreated men were over 55 years of age. Their mild to moderate thrombocytopenia was discovered incidentally and they remained symptom-free after a follow up of at least 5 years. The overall response rates of this cohort of Asian patients to corticosteroid therapy and splenectomy are compared with those reported from the West. Three deaths are recorded in this study, one from intracranial haemorrhage and 2 gram negative septicaemia in steroid-dependent postsplenectomy patients. The variable behaviour of this cohort of ITP patients emphasises the need for individualised management. Asymptomatic thrombocytopenia can be observed without treatment. Two fatalities from gram negative septicaemia in asplenic, steroid-dependent patients caution against the hasty recommendation of splenectomy for refractory ITP.