Thrombocytopenia in systemic-onset juvenile chronic arthritis: Report of two cases with unusual bone marrow features

Two children with systemic-onset juvenile chronic arthritis (S-JCA) sufferi ng from severe, symptomatic thrombocytopenia are reported. Case 1 is a 10-y ear-old girl who had fever, chronic polyarthritis and hepatosplenomegaly fo r 6 months and severe gum bleeding and generalised petechiae for 1 week. Im mune thrombocytopenic purpura (ITP) was indicated by bone marrow findings o f megakaryocytic hyperplasia, and her thrombocytopenia responded well to st eroid therapy without recurrence, but progressive, deforming polyarthritis with anaemia and thrombocytosis persisted. Case 2 is a 7-year-old girl who presented with spiking fever, arthritis and skin rashes and was suspected o f having S-JCA. She developed a severe nosebleed with impending shock while receiving full-dose aspirin. Pancytopenia and elevated liver enzymes were also noted. Bone marrow aspiration revealed erythroid hyperplasia, maturati on arrest of myeloid series with increased blasts, and adequate megakaryocy tes. Her thrombocytopenia resolved in 1 week without specific treatment. He r subsequent clinical course confirmed the diagnosis of S-JCA, while thromb ocytopenia did not recur during follow-up.