Sarvepalli Deepika, Rashid Mamoon Ur, Ullah Waqas, Zafar Yousaf, Khan Muzammil
Internal Medicine, Guntur Medical College, Guntur, IND.
Internal Medicine, AdventHealth, Orlando, USA.
Cureus. 2019 Sep 20;11(9):e5715. doi: 10.7759/cureus.5715.
Alemtuzumab, a humanized monoclonal antibody that targets surface molecule CD52, causes rapid and complete depletion of circulating T- and B-lymphocytes through antibody-dependent cell-mediated and complement-mediated cytotoxicity. Alemtuzumab has demonstrated superior efficacy compared to subcutaneous interferon beta-1a (SC IFNB-1a) in patients with multiple sclerosis (MS). Alemtuzumab treatment causes a rare and distinct form of secondary immune thrombocytopenic purpura (ITP), characterized by delayed onset, responsiveness to conventional therapies, and prolonged remission following treatment. In phase two and three clinical trials, the incidence of ITP was higher with alemtuzumab treatment compared to the patients receiving SC IFNB-1a. Here we report a case of ITP occurring two years after the first treatment with alemtuzumab. The patient recovered completely after a timely diagnosis and adequate treatment. Rigorous patient education and careful complete blood count (CBC) monitoring by the physician are critical for early identification and treatment of this potentially fatal disorder.
阿仑单抗是一种靶向表面分子CD52的人源化单克隆抗体，通过抗体依赖性细胞介导的细胞毒性和补体介导的细胞毒性作用，可迅速且完全地清除循环中的T淋巴细胞和B淋巴细胞。在多发性硬化症（MS）患者中，阿仑单抗已显示出优于皮下注射干扰素β-1a（SC IFNB-1a）的疗效。阿仑单抗治疗会引发一种罕见且独特的继发性免疫性血小板减少性紫癜（ITP），其特点为发病延迟、对传统疗法有反应以及治疗后缓解期延长。在二期和三期临床试验中，与接受SC IFNB-1a治疗的患者相比，接受阿仑单抗治疗的患者ITP发生率更高。在此，我们报告一例在首次使用阿仑单抗治疗两年后发生ITP的病例。该患者经及时诊断并接受充分治疗后完全康复。严格的患者教育以及医生仔细进行全血细胞计数（CBC）监测对于早期识别和治疗这种潜在致命性疾病至关重要。
