Brigden M L
Department of Medical Oncology, British Columbia Cancer Agency-Center for the Southern Interior, Kelowna, Canada.
Postgrad Med. 1999 Aug;106(2):135-42; quiz 185. doi: 10.3810/pgm.1999.08.653.
Multiple myeloma and MGUS are the two most common causes of monoclonal protein in serum or urine. The usually accepted diagnostic triad for multiple myeloma consists of a significant paraprotein in the serum or urine, more than 10% to 15% plasma cells in bone marrow, and the presence of bony lesions. Patients who meet the first two criteria but have no bony lesions, cytopenias, renal failure, or hypercalcemia may have smoldering myeloma, which often can be observed for a period of time before therapy is required. MGUS is characterized by a serum IgG monoclonal protein less than 3.5 g/dL or IgA paraprotein less than 2 g/dL, with no or only a small amount of protein in urine (Bence Jones protein < 1 g/24 hr). Less than 10% plasma cells are present in bone marrow, and patients have no lytic bony lesions, anemia, hypercalcemia, or renal insufficiency. Another important criterion for MGUS is stability of the monoclonal protein over time. Nonetheless, during long-term follow-up, an associated malignant process develops in about 30% of MGUS patients. Since none of the features defining MGUS is uniformly helpful in predicting the risk for malignant disease, patients should be followed up on a regular basis indefinitely.
多发性骨髓瘤和意义未明的单克隆丙种球蛋白病（MGUS）是血清或尿液中单克隆蛋白的两种最常见病因。通常公认的多发性骨髓瘤诊断三联征包括血清或尿液中存在显著的副蛋白、骨髓中浆细胞超过10%至15%以及存在骨病变。符合前两项标准但无骨病变、血细胞减少、肾衰竭或高钙血症的患者可能患有冒烟型骨髓瘤，在需要治疗之前通常可观察一段时间。MGUS的特征是血清IgG单克隆蛋白低于3.5 g/dL或IgA副蛋白低于2 g/dL，尿液中无或仅有少量蛋白（本周蛋白<1 g/24小时）。骨髓中浆细胞少于10%，患者无溶骨性骨病变、贫血、高钙血症或肾功能不全。MGUS的另一个重要标准是单克隆蛋白随时间的稳定性。尽管如此，在长期随访中，约30%的MGUS患者会发生相关的恶性病变。由于定义MGUS的特征均不能一致地有助于预测恶性疾病风险，因此应无限期定期对患者进行随访。
