Chew S T, Fitzwilliam J, Indridason O S, Kovalik E C
Division of Nephrology, Duke University Medical Center, Durham, NC, USA.
Am J Kidney Dis. 1999 Jul;34(1):135-9. doi: 10.1016/s0272-6386(99)70119-8.
The usefulness of routine serum protein electrophoresis (SPEP) and urine protein electrophoresis (UPEP) screening in the evaluation of proteinuria is not known. The data on the clinical utility of these tests in 165 male patients with proteinuria greater than 3 g/d of protein who were screened for the presence of an M-spike are presented. Two hundred fifty-four studies were performed (SPEP, 155; UPEP 99) in these 165 patients. Twenty-four studies (9.8%) were positive for an M-spike (15 serum; 9 urine samples) in 19 patients (11.5%). Fourteen patients (8.5%) had an M-spike in either serum or urine, five patients (3%) in both studies. Two of these 19 patients were diagnosed with myeloma and 1 patient was diagnosed with primary amyloidosis. The other 16 patients were diagnosed with monoclonal gammopathy of unknown significance (MGUS). The group with a positive M-spike was significantly older (mean +/- SEM, 65 +/- 2 years; range, 39 to 78 years v 58 +/- 1 years; range, 25 to 84 years; P = 0.03), had a lower incidence of coexistent diabetes (21.1% v 61.6%; P = 0. 01), and a lower serum albumin level (3.2 v 3.6 g/dL; P = 0.05). Using a multivariable logistic regression model, the presence of an M band was positively correlated with age (odds ratio [OR], 1.056; 95% confidence interval [CI], 1.006 to 1.108) and negatively correlated for serum albumin level (OR, 0.386; 95% CI, 0.184 to 0. 810), hematocrit (OR, 0.923; 95% CI, 0.852 to 1.001), and the presence of diabetes mellitus (OR, 0.128; 95% CI, 0.038 to 0.434). In summary, routine SPEP and UPEP screening in patients with proteinuria greater than 3 g/d of protein detected an M-spike in 11. 5% and myeloma in 1.2% of the patients. The cost per case of myeloma or MGUS discovered was $1,192.
常规血清蛋白电泳（SPEP）和尿蛋白电泳（UPEP）筛查在蛋白尿评估中的实用性尚不清楚。本文呈现了对165例蛋白尿大于3g/d且接受M蛋白筛查的男性患者进行这些检查的临床效用数据。在这165例患者中进行了254项检查（SPEP 155项；UPEP 99项）。24项检查（9.8%）M蛋白呈阳性（15份血清；9份尿液样本），涉及19例患者（11.5%）。14例患者（8.5%）血清或尿液中存在M蛋白，5例患者（3%）两项检查均呈阳性。这19例患者中有2例被诊断为骨髓瘤，1例被诊断为原发性淀粉样变性。其他16例患者被诊断为意义未明的单克隆丙种球蛋白病（MGUS）。M蛋白阳性组年龄显著更大（均值±标准误，65±2岁；范围39至78岁，而另一组为58±1岁；范围25至84岁；P = 0.03），合并糖尿病的发生率更低（21.1%对61.6%；P = 0.01），血清白蛋白水平更低（3.2对3.6g/dL；P = 0.05）。使用多变量逻辑回归模型，M带的存在与年龄呈正相关（比值比[OR]，1.056；95%置信区间[CI]，1.006至1.108），与血清白蛋白水平、血细胞比容、糖尿病的存在呈负相关（OR分别为0.386；95% CI，0.184至0.810；OR为0.923；95% CI，0.852至1.001；OR为0.128；95% CI，0.038至0.434）。总之，对蛋白尿大于3g/d的患者进行常规SPEP和UPEP筛查，在11.5%的患者中检测到M蛋白，在1.2%的患者中检测到骨髓瘤。发现每例骨髓瘤或MGUS的成本为1192美元。
