Duration and morbidity of chronic immune thrombocytopenic purpura in children: five-year follow-up of a Nordic cohort.

Objective: To describe the clinical course, morbidity and platelet recovery in an unselected Nordic cohort of children with chronic Immune Thrombocytopenic Purpura (ITP).

Methods: Prospective 5-year follow-up of 96 children with ITP lasting more than 6 months, with reporting of hospital admissions, severity of bleeding episodes and stabilization of platelet counts above 20, 50 and 150 × 10(9) /L.

Results: The estimated 5-year recovery rate was 52%; exclusion of 12 splenectomized children did not change the estimate. Events eliciting admission to hospital occurred in 39 (41%). Major haemorrhages occurred in eight children (8%), including a nonfatal intracranial haemorrhage in one child (1%). The overall admission rate was 0.4/year of thrombocytopenia, decreasing during follow-up as thrombocytopenia converted to milder degrees. Early recovery within 2 years of diagnosis occurred in 35%, was associated with low morbidity and was more likely in young children with abrupt onset of symptoms.

Conclusions: In a Nordic cohort of children with chronic ITP, one half had recovered 5 years after diagnosis, more than half never required hospitalization and <10% experienced serious bleeding episodes, always with a platelet count <20 × 10(9) /L. Aggressive management can be restricted to the minority of children with continuing severe thrombocytopenia and frequent, clinically significant bleeding events.