Ghasemi A, Keikhaei B, Ghodsi R
Assistant professor of pediatric hematology and oncology, faculty of medicine , Mashhad University of Medical Sciences, Mashhad,Iran.
Associate professor of pediatric hematology and oncology, Jondishapour University of Medical Sciences, Ahvaz, (research center for thalassemia and hemoglobinopathy).
Iran J Ped Hematol Oncol. 2014;4(3):114-7. Epub 2014 Jul 20.
Sickle hemoglobin is the most common abnormal hemoglobin in the United States. Hemoglobin S arises as a result of a single amino acid substitution (glutamic acid to valin at position 6 of the β-globine chain). The presence of fetal hemoglobin (HbF) plays a relatively protective role since a significant amount of HbF interferes with HbS polymerization, the pathogenesis mechanism of the vaso-occlusive symptoms that are the major contributor of the morbidity and mortality of this condition Thalassemia major and thalassemia intermedia have no specific molecular correlate but encompass a wide spectrum of clinical and laboratory abnormalities. Hydroxyurea (HU), an s-phase-specific and non-DNA-hypomethylating chemotherapeutic agents is capable of inducing HbF synthesis.
This study was done on 56 patients, 28 patients with sickle cell anemia (SCA) and 28 patients with intermediate or major β-thalassemia. Start dose of HU was 10 mg/kg per day and increased by 5 mg/kg per day every 4-6 weeks until toxicity or according to clinical response.
The side effects were dermatologic in 39.28%, neurologic 23.2%, gastrointestinal 17.5% and hematologic 10.71% of patients. the statistical analysis didn't show significant relationship between variables such as history of blood transfusion, duration of HU treatment, age of start HU, age of diagnosis, dose of HU and ethnic with occurrence of HU adverse effects.
The HU therapy in our patients tolerated well and side effects were minor to moderate, benign and transient.
镰状血红蛋白是美国最常见的异常血红蛋白。血红蛋白S是由于单个氨基酸取代（β珠蛋白链第6位的谷氨酸被缬氨酸取代）而产生的。胎儿血红蛋白（HbF）的存在起到了相对保护作用，因为大量的HbF会干扰HbS聚合，而HbS聚合是血管闭塞症状的发病机制，血管闭塞症状是这种疾病发病率和死亡率的主要促成因素。重型地中海贫血和中间型地中海贫血没有特定的分子关联，但包括广泛的临床和实验室异常。羟基脲（HU）是一种S期特异性且非DNA低甲基化的化疗药物，能够诱导HbF合成。
本研究对56例患者进行，其中28例镰状细胞贫血（SCA）患者和28例中间型或重型β地中海贫血患者。HU的起始剂量为每天10mg/kg，每4 - 6周每天增加5mg/kg，直至出现毒性反应或根据临床反应调整。
39.28%的患者出现皮肤方面的副作用，23.2%出现神经方面的副作用，17.5%出现胃肠道方面的副作用，10.71%出现血液学方面的副作用。统计分析未显示输血史、HU治疗持续时间、开始使用HU的年龄、诊断年龄、HU剂量和种族等变量与HU不良反应的发生之间存在显著关系。
我们的患者对HU治疗耐受性良好，副作用为轻至中度，良性且短暂。
