Laboratory of Clinical Chemistry and Haematology, Jeroen Bosch Hospital, Den Bosch, The Netherlands.
Clin Chem Lab Med. 2011 Nov 23;50(3):489-95. doi: 10.1515/CCLM.2011.793.
New monoclonal antibody-based assays for serum-free light chains (FLC) have become available.
In a clinical study with 541 patients, the new N Latex FLC assays were compared with the Freelite FLC assays and immunofixation electrophoresis (IF).
Comparison of the different FLC kappa (κ) assays showed a slope of 0.99 with a deviation of 5.0%, rs=0.92, for FLC lambda (λ) a slope of 1.22, deviation 13.8%, rs=0.90 and for the κ/λ ratio a slope of 0.72, deviation -4.6%, rs=0.72. The concordance for the FLC κ assays was 91%, for FLC λ 85% and κ/λ ratio 95%. The clinical sensitivity and specificity of the κ/λ ratios in the study were comparable: 60% and 99% for the N Latex FLC assay and 61% and 97% for the Freelite assay. In IF-FLC positive samples, the N Latex FLC κ/λ ratio scored 20/23 (87%) samples outside the reference range and Freelite 21/23 (91%). For IF-FLC negative samples, N Latex FLC assay κ/λ ratio scored 338/350 (97%) within the reference range and Freelite scored 332/350 (95%).
The concordance scores and the clinical sensitivity and specificity of the new N Latex FLC assays and Freelite assays appeared comparable, but there are some differences in measurement of concentrations between the methods.
新型基于单克隆抗体的血清游离轻链（FLC）检测方法已经问世。
在一项包含 541 名患者的临床研究中，新的 N Latex FLC 检测方法与 Freelite FLC 检测方法和免疫固定电泳（IFE）进行了比较。
不同κ（κ）型 FLC 检测方法的比较显示斜率为 0.99，偏差为 5.0%，rs=0.92；λ（λ）型 FLC 的斜率为 1.22，偏差为 13.8%，rs=0.90；κ/λ 比值的斜率为 0.72，偏差为-4.6%，rs=0.72。κ 型 FLC 检测方法的一致性为 91%，λ 型 FLC 为 85%，κ/λ 比值为 95%。在该研究中，κ/λ 比值的临床灵敏度和特异性相当：N Latex FLC 检测方法为 60%和 99%，Freelite 检测方法为 61%和 97%。在 IF-FLC 阳性样本中，N Latex FLC κ/λ 比值在参考范围内的 23 份样本中得分 20/23（87%），Freelite 为 21/23（91%）。对于 IF-FLC 阴性样本，N Latex FLC 检测方法 κ/λ 比值在参考范围内的 350 份样本中得分 338/350（97%），Freelite 得分 332/350（95%）。
新的 N Latex FLC 检测方法和 Freelite 检测方法的一致性评分以及临床灵敏度和特异性相当，但两种方法在浓度测量方面存在一些差异。
