Supplementary Material for: Antibodies against Carbonic Anhydrase in Patients with Aplastic Anemia

Background/Aims: Antibodies against carbonic anhydrase (CA) have been detected in patients with an aplastic anemia (AA)-like syndrome after autologous stem cell transplantation. Methods: We analyzed sera of 53 bona fide AA patients before and after treatment with anti-thymocyte globulin (ATG) or bone marrow transplantation for the presence of anti-CA antibodies. Results: Anti-CA antibodies were detected in 20 patients (38%) and were associated with older age at diagnosis of AA. Antibody-positive patients showed poor response to ATG treatment (complete response 14%) and inferior long-term survival (36% at 10 years), when compared to antibody-negative patients (complete response and 10-year survival both 64%). Two thirds of patients with antibodies at diagnosis of AA became antibody negative after treatment with ATG. Clearance of the antibody did not appear to be associated with hematological improvement. Conclusion: Antibodies against CA are detected frequently at diagnosis of AA, and their presence identifies a subset of patients with poor response to immunosuppressive treatment.

背景与目的：自体干细胞移植后出现类再生障碍性贫血（aplastic anemia, AA）综合征的患者中，已检出抗碳酸酐酶（carbonic anhydrase, CA）抗体。方法：我们对53例确诊AA患者在接受抗胸腺细胞球蛋白（anti-thymocyte globulin, ATG）治疗或骨髓移植前后的血清进行分析，以检测抗CA抗体的存在情况。结果：20例患者（38%）检出抗CA抗体，且该抗体阳性与AA确诊时年龄较大相关。与抗体阴性患者（完全缓解率和10年生存率均为64%）相比，抗体阳性患者对ATG治疗的应答较差（完全缓解率仅14%），长期生存率也更低（10年生存率为36%）。在AA确诊时抗体阳性的患者中，有三分之二在接受ATG治疗后转为抗体阴性。抗体清除似乎与血液学改善无关联。结论：AA确诊时常可检出抗CA抗体，其存在可提示一类对免疫抑制治疗应答不佳的患者亚群。