IgG-2κ轻链型多发性骨髓瘤三例临床和实验室特征

The clinical and laboratory features of IgG-2κ light chain multiple myeloma： analysis of three cases

目的 探讨IgG-2κ轻链型多发性骨髓瘤（MM）的临床和实验室特征.方法 结合相关文献分析3例IgG-2κ轻链型MM患者的临床资料和实验室结果 .结果3例患者中,男性2例,女性1例,年龄50~82岁,主要表现为腰痛、感染、贫血和肾功能损害,X线和（或）磁共振成像检查均显示多发溶骨性骨质破坏.血清IgG正常、轻度或明显升高,IgA和IgM均降低.血清和尿液κ轻链均明显升高,尿本周蛋白均阳性.2例患者血清蛋白电泳可见γ区形成双M蛋白峰.血清免疫固定电泳可见抗IgG单条带和抗κ轻链双条带.骨髓涂片可见异常浆细胞明显增多.2例患者分别接受DVD、VAD方案化疗达部分缓解和疾病稳定,1例患者因肺部感染、急性左心衰竭、急性肾衰竭放弃治疗.结论 IgG-2κ轻链型MM临床表现缺乏特征性,但某些实验室特点可能不同于IgG-κ轻链型,是否属于双克隆型MM有待研究证实.

Objective To investigate the clinical and laboratory features of IgG-2κ light chain multiple myeloma. Methods The clinical data and laboratory results of 2 multiple myeloma （MM） patients with IgG-2κ light chain were analyzed and the related literatures were reviewed. Results Two male and 1 female patients were 50-82 years old and mainly suffered with backache, infection, anemia and renal dysfunction. Multiple osteolytic bone destruction was detected in X-ray as well as magnetic resonance imaging （MRI）. The level of serum IgG was normal, slight or obviously increased, but the levels of IgA and IgM were decreased. The levels of κ light chain in serum and urine were both increased significantly, and Bence-Jones protein was positive. Double M protein peaks of serum in γ area were detected by protein electrophoresis in 2 patients. A single band of IgG and double bands of light chain κ were revealed by immunofixation electrophoresis. Bone marrow smear showed that abnormal plasma cells were increased obviously. One patient gave up chemotherapy because of lung infection, acute left heart failure and acute renal failure, the others 2 patients achieved partial remission and stable disease by receiving DVD and VAD chemotherapy. Conclusions IgG-2κ light chain MM lacks typical clinical presentation, but some laboratory characteristics may be different from those of IgG-κ light chain. Further researches are needed to confirm whether or not it belongs to biclonal MM.