Noé G, Augustin J, Hausdorf S, Rich I N, Kubanek B
Department of Transfusion Medicine, University of Ulm, German Red Cross Blood Bank, Germany.
Clin Exp Rheumatol. 1995 Jul-Aug;13(4):445-51.
Rheumatoid arthritis (RA) is generally associated with mild anaemia. The role of erythropoietin (EPO) in the pathogenesis of this anaemia of chronic disorders is still a matter of controversy. Therefore, in a multicenter study we investigated the serum EPO concentration in 124 patients with rheumatoid arthritis.
Patients with uncomplicated iron deficiency and haemolytic anaemia served as the reference group (n = 54). The measurements were performed with a specific and sensitive ELISA:
The mean EPO concentration +/- SD of the whole RA group (32.3 +/- 22.2 mU/ml) was elevated above normal. About 40% of the patients had underlying iron deficiency (defined by ferritin values < or = 60 ng/ml) and a significantly higher median EPO concentration than patients with normal iron stores (35.8 mU/ml versus 20.7 mU/ml; p < 0.001). The iron deficiency was associated with lower disease activity, as defined by the C reactive protein. In contrast to the reference group (r = -0.78), there was no significant correlation between EPO and the haematocrit in either RA subgroup, although the values for the RA patients were within the 95% prediction range of the reference group. In addition to the EPO, we investigated the soluble transferrin receptor level as a measure of bone marrow erythropoiesis. The level in iron-replete RA subjects was about 1.6 times higher than in normal persons, reflecting a relatively hypoproliferative erythropoietic activity.
This study shows that the EPO concentrations in RA are elevated above normal but lower than expected, and that the normal relationship between EPO and the degree of anaemia is impaired.
类风湿关节炎（RA）通常与轻度贫血相关。促红细胞生成素（EPO）在这种慢性疾病贫血发病机制中的作用仍存在争议。因此，在一项多中心研究中，我们调查了124例类风湿关节炎患者的血清EPO浓度。
将无并发症的缺铁性贫血和溶血性贫血患者作为参照组（n = 54）。采用特异性和敏感性均较高的酶联免疫吸附测定法（ELISA）进行检测。
整个RA组的平均EPO浓度±标准差（32.3±22.2 mU/ml）高于正常水平。约40%的患者存在潜在缺铁（定义为铁蛋白值≤60 ng/ml），且其EPO浓度中位数显著高于铁储备正常的患者（35.8 mU/ml对20.7 mU/ml；p<0.001）。缺铁与较低的疾病活动度相关，疾病活动度由C反应蛋白定义。与参照组（r = -0.78）不同，在两个RA亚组中，EPO与血细胞比容之间均无显著相关性，尽管RA患者的值在参照组的95%预测范围内。除EPO外，我们还检测了可溶性转铁蛋白受体水平，以衡量骨髓红细胞生成情况。铁储备充足的RA患者的该水平约比正常人高1.6倍，反映出红细胞生成活动相对增殖不足。
本研究表明，RA患者的EPO浓度高于正常水平，但低于预期，且EPO与贫血程度之间的正常关系受到损害。
