Messiaen Anne-Sophie, De Sloovere Maxime M W, Claus Paul-Emile, Vercammen Martine, Van Hoovels Lieve, Heylen Olivier, Debrabandere Johan, Vanpoucke Hilde, De Smet Dieter
From the Department of Laboratory Medicine, AZ Delta Roeselare-Menen, Roeselare, Belgium.
Department of Laboratory Medicine, AZ Sint-Jan Brugge-Oostende, Brugge, Belgium.
Am J Clin Pathol. 2017 Jun 1;147(6):611-622. doi: 10.1093/ajcp/aqx037.
Free light chain (FLC) measurement gained a lot of interest for diagnostic workup of monoclonal gammopathy.
We evaluated the performance of turbidimetric polyclonal Freelite (The Binding Site, Birmingham, UK) assays on Cobas 6000 (Roche Diagnostics, Rotkreuz, Switzerland) and nephelometric monoclonal N Latex (Siemens Healthcare Diagnostics, Marburg, Germany) assays on BN ProSpec (Dade Behring, Deerfield, IL) vs established nephelometric Freelite assays on BN ProSpec.
Analytical performance was acceptable. Method comparison (n = 118) showed significant proportional FLC differences for N Latex assays. However, good correlation and clinical concordance were shown. Recovery study in the low concentration range demonstrated consistent over- and underrecovery for Freelite reagents, hampering future research on prognostic value of suppressed noninvolved FLC. Antigen excess detection was successful for κ FLC in three-fourths of cases with Freelite reagents and in all cases with N Latex reagents. However, the latter resulted in underestimated κ FLC concentrations.
FLC analysis requires continuous awareness of analytical limitations. Monitoring of disease response requires FLC analysis on the same platform using the same reagents.
游离轻链（FLC）检测在单克隆丙种球蛋白病的诊断检查中备受关注。
我们评估了在Cobas 6000（罗氏诊断公司，瑞士罗特kreuz）上进行的比浊法多克隆Freelite（英国伯明翰的The Binding Site公司）检测以及在BN ProSpec（德国达德拜林公司，伊利诺伊州迪尔菲尔德）上进行的散射比浊法单克隆N Latex（西门子医疗诊断公司，德国马尔堡）检测与在BN ProSpec上既定的散射比浊法Freelite检测的性能。
分析性能可接受。方法比较（n = 118）显示N Latex检测的FLC存在显著比例差异。然而，显示出良好的相关性和临床一致性。低浓度范围内的回收率研究表明，Freelite试剂存在一致的回收率过高和过低情况，这妨碍了未来对受抑制的未受累FLC预后价值的研究。对于κ FLC，使用Freelite试剂在四分之三的病例中成功检测到抗原过量，使用N Latex试剂在所有病例中均成功检测到抗原过量。然而，后者导致κ FLC浓度被低估。
FLC分析需要持续关注分析局限性。监测疾病反应需要在同一平台上使用相同试剂进行FLC分析。
