Division of Nephrology, Huashan Hospital, Fudan University, Shanghai, China.
Division of Nephrology, The Second Affiliated Hospital of Guangxi Medical University, Nanning, China.
Front Immunol. 2024 May 3;15:1390958. doi: 10.3389/fimmu.2024.1390958. eCollection 2024.
This study presents two cases of type II mixed cryoglobulinemia. One case is essential, while the other is presumably associated with hepatitis B virus (HBV) infection. Both patients tested positive for monoclonal IgMκ, but negative for MyD88 mutation. They showed resistance to rituximab combined with a glucosteroid regimen, but responded positively to BTK inhibitors. These cases highlight the remarkable effectiveness of BTK inhibitors in treating refractory type II cryoglobulinemia without MyD88 mutation. The first patient achieved rapid complete remission of nephrotic syndrome within one month of starting ibrutinib, along with a significant reduction in cryoglobulin levels and abnormal clonal cells. The second patient had a rapid disappearance of rash within three days and accelerated wound healing within one week of initiating orelabrutinib, accompanied by a reduction in C-reactive protein. However, there was no reduction in cryoglobulin levels during the 12-month follow-up. These findings suggest varied mechanisms of action of BTK inhibitors in type II cryoglobulinemia through different mechanisms.
本研究报告了两例 II 型混合性冷球蛋白血症病例。其中一例为原发性，另一例可能与乙型肝炎病毒（HBV）感染相关。两位患者均检测出单克隆 IgMκ 阳性，但 MyD88 突变阴性。他们对利妥昔单抗联合糖皮质激素方案治疗有抵抗，但对 BTK 抑制剂反应良好。这些病例突出表明 BTK 抑制剂在治疗无 MyD88 突变的难治性 II 型冷球蛋白血症方面具有显著疗效。第一例患者在开始使用伊布替尼后一个月内迅速完全缓解肾病综合征，同时冷球蛋白水平和异常克隆细胞显著减少。第二例患者在开始奥雷巴替尼后三天内皮疹迅速消失，一周内伤口愈合加速，同时 C 反应蛋白降低。然而，在 12 个月的随访期间，冷球蛋白水平没有降低。这些发现提示 BTK 抑制剂在 II 型冷球蛋白血症中的作用机制不同。
