Background Immune thrombocytopenia (ITP) is characterised by a low platelet count and an increased risk of bleeding. Rheumatologist usually diagnosed ITP associated with systemic lupus erythematosus (SLE) but patients not always meet criteria.
Objectives To describe clinical features and treatment in a series of patients with ITP.
Patients and Methods We identified 11 patients with ITP and made a description of our experience.
Results The mean age was 38.1 ± 12 years (81.8% female) with a and mean disease duration of 9.18 ± 4.68 years. Four of the 11 patients had some bleeding, being metrorrhagia the most common.
The median platelet count in the diagnosis was 42,763 ± 23221/microL, and actually 147800 ± 136144/microL.
Nine of the 11 patients had positive ANA (none of them antiDNA), 72.7% presented hypocomplementemia and antiphospholipid antibodies were present in only 2 patients.
Eight of the 11 patients did not meet criteria for SLE.
All the patients received glucocorticoids. The 63.6% were treated with azathioprine and/or hydroxychloroquine. Intravenous immunoglobulin were used in 3 patients. Three patients underwent splenectomy. Rituximab was used in 2 patients.
Two patients ANA + had a platelet count below 10000/microL without bleeding. One was treated with corticosteroids and hydroxychloroquine achieving a platelet count of 70000/microL, and the other one with azathioprine, rituximab and splenectomy with normal levels of platelets actually.
The 3 patients with diagnosis of SLE, have a mean number of platelets in the diagnosis of 53266.66 ± 15362.73, and despite treatment with glucocorticoids, hydroxychloroquine, azathioprine and rituximab in 2 of then (positive for antiphospholipids antibody) had the worst results with a median platelet count actually of 48333.33 ± 26764.4
DISCUSSION Patients with ITP can be very heterogeneous. Most of them can't be classified as SLE.
The pathogenesis of ITP is based on the combination of increased platelet destruction and inhibition of platelet production by essentially autoantibodies against GPIIb / III, but in SLE and especially with antiphospholipid antibodies, must be other associated mechanisms such as increased platelet consumption by thrombotic microangiopathy, that can modified treatment response.
Further studies with more patients would be necessary to analyse the differences in SLE and no SLE patients with ITP.