RESUMO
INTRODUCTION: Immune thrombocytopenia (ITP) is known as an immune-mediated disease and often evolves to chronic type in adult. Corticosteroids only work in around 60% of patients. This study evaluated the roles of subgroup lymphocytes from peripheral blood in ITP adults with different treatment response. METHODS: Between October 2009 and March 2017, 37 adults were newly diagnosed as ITP requiring treatment. The patients were separated into two groups: 23 patients with platelet count <50,000/µL with corticosteroid dependence or second-line treatment (Poor-responder Group), and 14 patients with platelet counts <50,000/µL with standard steroid treatment, which stopped within three months (Good-responder Group). Subgroup lymphocyte percentages of peripheral blood were determined through flow cytometry before treatment. Data analysis with Mann-Whitney test and receiver operating characteristic curves were performed using GraphPad Prism (Version 7). A p-value of <0.05 was considered significant. RESULTS: Lymphocyte percentage was significantly lower in Poor-responder Group than in Good-responder Group (pâ¯=â¯0.008). In subgroup lymphocytes, higher percentages of CD19+ B lymphocytes were found in Good-responder Group (pâ¯=â¯0.03). In Poor-responder Group, a higher CD2+ and CD56+ lymphocytes were observed (pâ¯=â¯0.02 and 0.03). By the cut-off value of percentage of CD56+ lymphocytes with 24.5% or CD2+ lymphocytes with 85.7%, the specificity showed 92.86%. CONCLUSIONS: This study found that newly diagnosed ITP patients with increased percentages of CD56+ or CD2+ lymphocytes in peripheral blood associated with a poorer response to steroid treatment.