The comparative immunophenotypic analysis of paediatric and adults bone marrow lymphocytes' in chronic Immune thrombocytopenic purpura (ITP) refractory to intravenous immunoglobulin and corticosteroids.

Immune thrombocytopenic purpura (ITP) is an acquired autoimmune disorder marked by increased platelet destruction and reduced production, primarily due to the presence of autoantibodies. While many patients respond well to therapy, a subset remains refractory, posing a significant challenge for clinicians and patients alike. This study aimed to evaluate the bone marrow lymphocyte composition in both pediatric and adult patients with refractory ITP, with the goal of uncovering possible reasons for treatment resistance. This case-control study was conducted during the period from May 2019 to December 2024, involved 30 children and 37 adults diagnosed with refractory ITP, along with 60 age- and sex-matched normal controls. All participants underwent bone marrow aspiration, followed by immunophenotyping using a standard panel. Children with refractory ITP exhibited significantly higher percentages of hematogones and mature B cells in the bone marrow (8.27% ± 4.50% and 4.52% ± 3.82%, respectively) compared to adults (1.17% ± 2.18% and 1.89% ± 1.33%). In contrast, the adult group showed elevated levels of T cells (CD3+), averaging 11.6% ± 6.25% compared to 7.80% ± 3.12% in the pediatric group (p = 0.014). Additionally, both CD4+ and CD8+ T cells were significantly more abundant in adults (6.62% ± 4.82% and 7.89% ± 7.02%). Significant differences were also observed between patient and control groups in the proportions of CD3+, CD4+, CD4/CD8 ratios, hematogones, and mature B cells. In conclusion, distinct immunophenotypic profiles in bone marrow lymphocytes were identified between pediatric and adult patients with refractory ITP. These findings highlight potential age-related differences in disease mechanisms, which could inform more targeted approaches to diagnosis and management.