Thrombocytopenia in Systemic Lupus Erythematosus

The aim of the study was to examine the clinical characteristics and prognosis according to severity of thrombocytopenia and response to treatment for thrombocytopenia in patients with systemic lupus erythematosus (SLE). We retrospectively evaluated 230 SLE patients with thrombocytopenia, and reviewed their clinical data and laboratory findings. Thrombocytopenia was defined as platelet counts under 100,000/mm, and patients were divided into 3 thrombocytopenia groups according to severity: mild (platelet counts >50,000/mm), moderate (>20,000/ mm, 50,000/mm), and severe ( 20,000/mm). Clinical characteristics, treatments, and prognoses were compared among the groups. Furthermore, complete remission of thrombocytopenia was defined as platelet counts >100,000/mm after treatment. There was no significant difference in clinical or laboratory findings among the groups according to severity of thrombocytopenia. However, hemorrhagic complications were more frequent in severe thrombocytopenia (P< 0.001) and mortality was also higher (P1⁄4 0.001). Complete remission was achieved in 85.2% of patients. The clinical characteristics and modality of treatment did not differ between the patients with and without complete remission. Mortality in patients with complete remission (1.5%) was significantly lower than in those without complete remission (29.4%, P< 0.001). Survival was significantly higher in patients with complete remission from thrombocytopenia (odds ratio1⁄4 0.049, 95% confidence interval: 0.013–0.191, P< 0.001). The severity of thrombocytopenia in SLE patients can be a useful independent prognostic factor to predict survival. Moreover, complete remission of thrombocytopenia after treatment is an important prognostic factor. The severity of thrombocytopenia and response to treatment should be closely monitored to predict prognosis in SLE patients. (Medicine 95(6):e2818) Abbreviations: ACR = American College of Rheumatology, ANA = antinuclear antibodies, anti-dsDNA = anti-double-stranded DNA, oung-Hwan Ahn, M m, MD, , PhD, and Hyoun-Ah Kim, MD, PhD INTRODUCTION S ystemic lupus erythematosus (SLE) is an autoimmune disease affecting diverse organs of the body and causing chronic inflammation. It shows a broad spectrum of clinical manifestations and is associated with several autoantibodies. Hematologic abnormalities, including thrombocytopenia and leucopenia, are common clinical manifestations of SLE. Thrombocytopenia is known as one of the hematological criteria of SLE, according to the American College of Rheumatology (ACR) classification criteria. Its prevalence has been estimated to range from 10% to 40%, but severe thrombocytopenia is relatively uncommon. There have been several studies about the association between thrombocytopenia and prognosis in SLE patients. In previous studies, thrombocytopenia has been shown to be associated with other severe clinical manifestations of SLE, such as neuropsychiatric symptoms, kidney involvement, and hemolytic anemia. It is also known to have an association with the prognosis of SLE, including death. However, the characteristics and prognosis according to severity of thrombocytopenia have been examined in few studies. Moreover, the prognosis according to remission of thrombocytopenia is unknown. Therefore, in this study, we retrospectively reviewed patients with SLE who developed thrombocytopenia, and analyzed differences in clinical and laboratory findings and prognosis according to severity of thrombocytopenia. Furthermore, we investigated the treatment of thrombocytopenia, and whether remission of thrombocytopenia was associated with other clinical manifestations and prognosis.