Department of Pediatric Nephrology, Armand Trousseau Hospital, AP-HP 75012, Paris, France.
Pediatr Nephrol. 2013 Mar;28(3):447-51. doi: 10.1007/s00467-012-2361-z. Epub 2012 Dec 5.
Rituximab (RTX) is a promising strategy for treating steroid-dependent idiopathic nephrotic syndrome (SDNS). RTX induces profound B-cell depletion, suggesting hypogammaglobulinemia as a potential side effect after long-term treatment.
We analyzed immunoglobulin G (IgG) levels in 12 pediatric patients on RTX with a B-cell depletion of a minimum of 3 months and compared the results to 16 patients on orally administered immunosuppressive drugs, such as mycophenolate mofetil (MMF) and/or cyclosporine A (CyA). All patients were in stable remission of SDNS at the time of IgG analysis.
IgG levels in the RTX group before RTX introduction were 6.2 ± 1.0 g/L and were not significantly different from the MMF/CyA group (8.2 ± 2.5 g/L). In the MMF/CyA group, five patients had at least one episode of hypogammaglobulinemia. In two of them, this episode was prolonged (>3 months), and only one required IgG supplementation. In the RTX group, eight patients had decreased IgG levels before RTX infusion. After RTX, hypogammaglobulinemia persisted in seven among those eight patients. No decreased IgG plasma levels were noted in patients with normal baseline IgG levels before RTX treatment.
RTX does not seem to directly induce decreased IgG levels in patients with SDNS, but it seems to prolong a preexisting low IgG levels.
利妥昔单抗（RTX）是治疗激素依赖型特发性肾病综合征（SDNS）的一种有前途的策略。RTX 可诱导显著的 B 细胞耗竭，这表明长期治疗后可能出现低丙种球蛋白血症。
我们分析了 12 例接受 RTX 治疗且 B 细胞耗竭至少 3 个月的儿科患者的免疫球蛋白 G（IgG）水平，并将结果与 16 例接受口服免疫抑制剂（如霉酚酸酯和/或环孢素 A）治疗的患者进行了比较。所有患者在 IgG 分析时均处于 SDNS 稳定缓解期。
RTX 组在引入 RTX 前 IgG 水平为 6.2±1.0 g/L，与 MMF/CyA 组（8.2±2.5 g/L）无显著差异。在 MMF/CyA 组中，有 5 例患者至少发生过一次低丙种球蛋白血症。其中 2 例持续时间较长（>3 个月），仅 1 例需要补充 IgG。在 RTX 组，有 8 例患者在 RTX 输注前 IgG 水平下降。在这 8 例患者中，有 7 例在接受 RTX 后持续存在低 IgG 血症。在接受 RTX 治疗前 IgG 水平正常的患者中，未观察到 IgG 血浆水平下降。
RTX 似乎不会直接导致 SDNS 患者 IgG 水平降低，但似乎会延长预先存在的低 IgG 水平。
