Srinivas Upendra, Mahapatra Manoranjan, Saxena Renu, Pati Hara Prasad
Department of Hematology, All India Institute of Medical Sciences, New Delhi, India.
Hematology. 2007 Jun;12(3):245-8. doi: 10.1080/10245330701255056.
Pure red cell aplasia (PRCA) is an uncommon disorder, characterized by transfusion dependent anemia, reticulocytopenia with selective aplasia or paucity of erythroid cells in bone marrow. There are only a few large series of PRCA reported in literature. This is the largest single center series of PRCA from India.
To evaluate the utility of Immunohistochemistry with Glycophorin A on bone marrow biopsies in quantitating the cut-off percentage of erythroid blasts required for diagnosis, as the upper cut-off percentage of erythroblasts for establishing a diagnosis of PRCA is still not clear.
The clinical data were obtained from patients' case files. Immunohistochemistry with Glycophorin A was performed using an immunoperoxidase technique and percentage of Glycophorin A positive cells of all nucleated cells was calculated by two independent observers.
In our study, bone marrow aspirates showed a variable percentage of erythroblasts ranging from 2 to 12% (mean 6.3%) in children and from 1 to 8% (mean 4.6%) in adults on Giemsa smears. Immunohistochemistry (IHC) with Glycophorin A showed a mean positive cell % of 8.2 (range 2-16%) and 6.8 (1-9%) in pediatric and adult respectively against a mean of 28% (range 21-39%) in idiopathic thrombocytopenia (ITP) cases. Treatment with prednisone showed good response in a majority of both adults and childhood PRCA. Cyclosporine was found to be a good alternative in prednisone non-responders. Thymectomy was beneficial in patients with thymoma.
A higher percentage of erythroid cells (>5%) does not exclude a diagnosis of PRCA in an appropriate clinical setting and therefore can be managed as PRCA.
纯红细胞再生障碍性贫血(PRCA)是一种罕见疾病,其特征为依赖输血的贫血、网织红细胞减少以及骨髓中红系细胞选择性再生障碍或数量减少。文献中仅有少数关于PRCA的大型系列报道。这是来自印度的最大单中心PRCA系列研究。
鉴于诊断PRCA时红系原始细胞的上限百分比仍不明确,评估骨髓活检中使用血型糖蛋白A进行免疫组织化学在定量诊断所需红系原始细胞临界百分比方面的效用。
从患者病历中获取临床数据。采用免疫过氧化物酶技术进行血型糖蛋白A免疫组织化学检测,由两名独立观察者计算所有有核细胞中血型糖蛋白A阳性细胞的百分比。
在我们的研究中,骨髓涂片显示,吉姆萨染色下儿童红系原始细胞百分比为2%至12%(平均6.3%),成人红系原始细胞百分比为1%至8%(平均4.6%)免疫组织化学(IHC)检测显示,儿童和成人血型糖蛋白A阳性细胞平均百分比分别为8%(范围2% - 16%)和6.8%(1% - 9%)而特发性血小板减少性紫癜(ITP)病例中平均为28%(范围21% - 39%)。泼尼松治疗对大多数成人和儿童PRCA患者均显示出良好疗效。对于泼尼松治疗无反应者,环孢素是一种良好的替代药物。胸腺切除术对胸腺瘤患者有益。
在适当的临床背景下,较高百分比的红系细胞(>5%)并不能排除PRCA的诊断,因此可按PRCA进行处理。