Department of Hematology/Oncology, University Children's Hospital Basel, Basel, Switzerland.
Faculty of Medicine, University of Basel, Basel, Switzerland.
Blood Adv. 2021 Mar 23;5(6):1617-1626. doi: 10.1182/bloodadvances.2020003004.
Primary immune thrombocytopenia (ITP) in children is a diagnosis of exclusion, but cases of secondary ITP and nonimmune thrombocytopenia (non-IT) are generally difficult to recognize in a timely fashion. We describe a pediatric population with a revised diagnosis of secondary ITP or non-IT within 24 months of follow-up. Data were extracted from the Pediatric and Adult Registry on Chronic ITP, an international multicenter registry collecting data prospectively in patients with newly diagnosed primary ITP. Between 2004 and 2019, a total of 3974 children aged 3 months to 16 years were included. Secondary ITP and non-IT were reported in 113 patients (63 female subjects). Infectious (n = 53) and autoimmune (n = 42) diseases were identified as the main causes, with median ages at diagnosis of 3.2 years (interquartile range: 1.2; 6.7 years) and 12.4 years (interquartile range: 7.6; 13.7 years), respectively. Other causes included malignancies, aplastic anemia, immunodeficiency, and drug use. Patients with malignancy and aplastic anemia had significantly higher initial platelet counts (37 and 52 × 109/L) than did those with infection or autoimmune diseases (12 and 13 × 109/L). Characteristics of patients with secondary ITP due to infection were similar to those of children with primary ITP at first presentation, indicating similar mechanisms. Significant differences were found for age, sex, comorbidities, initial bleeding, sustained need for treatment, and disease persistence for the remaining noninfectious group compared with primary ITP. Based on our findings, we propose a diagnostic algorithm that may serve as a basis for further discussion and prospective trials.
儿童原发性免疫性血小板减少症（ITP）是一种排他性诊断，但继发性 ITP 和非免疫性血小板减少症（非 ITP）的病例通常难以及时识别。我们描述了一组在随访 24 个月内被重新诊断为继发性 ITP 或非 ITP 的儿科患者。这些数据是从慢性 ITP 儿科和成人登记处提取的，这是一个国际多中心登记处，前瞻性地收集新诊断的原发性 ITP 患者的数据。2004 年至 2019 年期间，共纳入了 3974 名 3 个月至 16 岁的儿童。报告了 113 例继发性 ITP 和非 ITP 患者（63 名女性）。感染（n=53）和自身免疫性疾病（n=42）被确定为主要病因，诊断时的中位年龄分别为 3.2 岁（四分位距：1.2；6.7 岁）和 12.4 岁（四分位距：7.6；13.7 岁）。其他病因包括恶性肿瘤、再生障碍性贫血、免疫缺陷和药物使用。恶性肿瘤和再生障碍性贫血患者的初始血小板计数明显高于感染或自身免疫性疾病患者（分别为 37 和 52×109/L 和 12 和 13×109/L）。感染导致的继发性 ITP 患者的特征与初次表现为原发性 ITP 的儿童相似，表明其发病机制相似。与原发性 ITP 相比，其余非传染性组在年龄、性别、合并症、初始出血、持续治疗需求和疾病持续存在方面存在显著差异。基于我们的发现，我们提出了一个诊断算法，可作为进一步讨论和前瞻性试验的基础。
