TY - JOUR
T1 - Verification of Newly FDA-Approved Kappa and Lambda Free Light Chain Assays on a Previously Untested Platform
AU - Muluhngwi, Penn
AU - Sharp, Cierra N.
AU - Pozzi, Nicole
AU - Elin, Ronald J.
AU - Jortani, Saeed A.
N1 - Publisher Copyright:
© 2019 American Association for Clinical Chemistry.
PY - 2019/11/1
Y1 - 2019/11/1
N2 - Background: κ and λ free light chains (FLCs) are monitored to aid in the diagnosis of plasma cell disorders. Our goal was to validate the Diazyme Human κ and λ assays on Beckman Coulter UniCel DxC 800 Synchron and compare to Freelite κ and λ assays on Roche Cobas Integra. Methods: Linearity verification, within- and between-run precision, method comparison, and reference range (RR) verification were conducted using CLSI guidelines. Statistical analysis was performed using EP Evaluator®. Mean, SD, CV, and bias were determined. Results: Diazyme κ FLC assay was linear within 0.00 –191.00 mg/L. Diazyme λ FLC assay was linear within 0.00 –205.30 mg/L. Diazyme κ FLC QC1 had a mean of 16.70 mg/L, CV of 7.0%. QC2 had a mean of 33.37 mg/L, CV of 2.6%. Diazyme λ FLC QC1 had a mean of 21.73 mg/L, CV of 2.3%. QC2 had a mean of 42.05 mg/L, CV of 1.5%. Bias of DxC-Diazyme FLCs compared to Integra-Freelite FLCs was −2.55 mg/L (κ FLC), and 4.54 mg/L (λ FLC). Qualitative comparison of κ FLC assays indicated 100% agreement for both normal and abnormal values. For λ FLC assay, agreement was 95% for normal values and 75% for abnormal values. For κ/λ ratio there was 50% agreement for normal values, and 100% for abnormal values. For RR verification, 1 sample was outside the Diazyme κ RR. For λ, all samples were within the manufacturer's RR. Conclusions: Diazyme assays for FLCs have excellent precision and accuracy and are comparable to Freelite assays.
AB - Background: κ and λ free light chains (FLCs) are monitored to aid in the diagnosis of plasma cell disorders. Our goal was to validate the Diazyme Human κ and λ assays on Beckman Coulter UniCel DxC 800 Synchron and compare to Freelite κ and λ assays on Roche Cobas Integra. Methods: Linearity verification, within- and between-run precision, method comparison, and reference range (RR) verification were conducted using CLSI guidelines. Statistical analysis was performed using EP Evaluator®. Mean, SD, CV, and bias were determined. Results: Diazyme κ FLC assay was linear within 0.00 –191.00 mg/L. Diazyme λ FLC assay was linear within 0.00 –205.30 mg/L. Diazyme κ FLC QC1 had a mean of 16.70 mg/L, CV of 7.0%. QC2 had a mean of 33.37 mg/L, CV of 2.6%. Diazyme λ FLC QC1 had a mean of 21.73 mg/L, CV of 2.3%. QC2 had a mean of 42.05 mg/L, CV of 1.5%. Bias of DxC-Diazyme FLCs compared to Integra-Freelite FLCs was −2.55 mg/L (κ FLC), and 4.54 mg/L (λ FLC). Qualitative comparison of κ FLC assays indicated 100% agreement for both normal and abnormal values. For λ FLC assay, agreement was 95% for normal values and 75% for abnormal values. For κ/λ ratio there was 50% agreement for normal values, and 100% for abnormal values. For RR verification, 1 sample was outside the Diazyme κ RR. For λ, all samples were within the manufacturer's RR. Conclusions: Diazyme assays for FLCs have excellent precision and accuracy and are comparable to Freelite assays.
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U2 - 10.1373/jalm.2019.029215
DO - 10.1373/jalm.2019.029215
M3 - Article
C2 - 31659070
AN - SCOPUS:85091193162
SN - 2576-9456
VL - 4
SP - 323
EP - 330
JO - The journal of applied laboratory medicine
JF - The journal of applied laboratory medicine
IS - 3
ER -