OBJECTIVE: To validate the use of a Roche serum beta-2-microglobulin (B2MG) kit for urinary B2MG measurements, and to establish reference limits for urinary B2MG/creatinine ratio from healthy individuals. DESIGN AND METHODS: The Roche B2MG Tina-Quant serum kit was used to measure urinary B2MG immunoturbidimetrically. RESULTS: Using human urine as a diluent, the B2MG method was linear from 73-2156 μg/L. The imprecision on a commercially available urine QC was 4.4% at a concentration of 380 μg/L. Limit of quantification at <20% CV was 40 μg/L. Method comparison with Immulite 2000 (Siemens) yielded slope=1.180 (95% CI 1.14-1.22), intercept=11.5 (95% CI -3.6-26.6), SEE=27.6 and r=0.99 (n=26) by the Deming regression analysis. The upper reference limit of B2MG/creatinine ratio determined from 195 healthy adults was 29 μg/mmol (97.5th centile). CONCLUSIONS: The serum B2MG Tina Quant reagent kit is acceptable to measure urinary B2MG.
OBJECTIVE: To validate the use of a Roche serum beta-2-microglobulin (B2MG) kit for urinary B2MG measurements, and to establish reference limits for urinary B2MG/creatinine ratio from healthy individuals. DESIGN AND METHODS: The Roche B2MG Tina-Quant serum kit was used to measure urinary B2MG immunoturbidimetrically. RESULTS: Using human urine as a diluent, the B2MG method was linear from 73-2156 μg/L. The imprecision on a commercially available urine QC was 4.4% at a concentration of 380 μg/L. Limit of quantification at <20% CV was 40 μg/L. Method comparison with Immulite 2000 (Siemens) yielded slope=1.180 (95% CI 1.14-1.22), intercept=11.5 (95% CI -3.6-26.6), SEE=27.6 and r=0.99 (n=26) by the Deming regression analysis. The upper reference limit of B2MG/creatinine ratio determined from 195 healthy adults was 29 μg/mmol (97.5th centile). CONCLUSIONS: The serum B2MG Tina Quant reagent kit is acceptable to measure urinary B2MG.
Authors: Casey M Rebholz; Lesley A Inker; Yuan Chen; Menglu Liang; Meredith C Foster; John H Eckfeldt; Paul L Kimmel; Ramachandran S Vasan; Harold I Feldman; Mark J Sarnak; Chi-Yuan Hsu; Andrew S Levey; Josef Coresh Journal: Am J Kidney Dis Date: 2017-06-23 Impact factor: 8.860