Tomizawa Mitsuru, Hori Shunta, Inoue Kuniaki, Yoneda Tatsuo, Fujimoto Kiyohide
Department of Urology, Nara Medical University, Kashihara, JPN.
Cureus. 2025 Mar 25;17(3):e81183. doi: 10.7759/cureus.81183. eCollection 2025 Mar.
The prevalence of monoclonal gammopathy of undetermined significance increases with age, and there may be undiagnosed patients among kidney transplant recipients. A 69-year-old woman underwent ABO-incompatible living-donor kidney transplantation. Her renal function improved immediately postoperatively. Her hemoglobin level gradually increased to 10.5 g/dL at 3 months postoperatively but gradually decreased to 7.3 g/dL at 9 months postoperatively. We administered an erythropoiesis-stimulating agent and consulted the Department of Hematology. Bone marrow aspiration revealed that the pathological monoclonal plasma cells constituted 4.6% of bone marrow cells. Immunoelectrophoresis identified serum monoclonal proteins as immunoglobulin G lambda. The patient was diagnosed with monoclonal gammopathy of undetermined significance, and free light-chain measurements were performed regularly. No disease progression was observed. The anemia improved with the administration of an erythropoiesis-stimulating agent. Monoclonal gammopathy of undetermined significance should be explored as a cause of persistent anemia after kidney transplantation.
意义未明的单克隆丙种球蛋白病的患病率随年龄增长而增加，肾移植受者中可能存在未被诊断的患者。一名69岁女性接受了ABO血型不相容的活体供肾移植。术后她的肾功能立即改善。术后3个月时，她的血红蛋白水平逐渐升至10.5 g/dL，但术后9个月时逐渐降至7.3 g/dL。我们给予了促红细胞生成素并咨询了血液科。骨髓穿刺显示病理性单克隆浆细胞占骨髓细胞的4.6%。免疫电泳鉴定血清单克隆蛋白为免疫球蛋白G λ。该患者被诊断为意义未明的单克隆丙种球蛋白病，并定期进行游离轻链检测。未观察到疾病进展。给予促红细胞生成素后贫血得到改善。意义未明的单克隆丙种球蛋白病应被视为肾移植后持续性贫血的一个原因进行探究。
