title: Validating urinary measurement of beta-2-microglobulin with a Roche reagent kit designed for serum measurements.
abstract: 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.
  
  
  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: Department of Clinical Pathology, Sunnybrook Health Sciences Centre, Toronto, ON, M4N 3M5, Canada. PC.Chan@sunnybrook.ca
authors: Pak Cheung R
authors: PC
authors: Chan
authors: Vathany
authors: V
authors: Kulasingam
authors: Bonny
authors: B
authors: Lem-Ragosnig
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D003404:Creatinine / Q000652:urine; D005260:Female; D006801:Humans; D057230:Limit of Detection; D008297:Male; D008875:Middle Aged; D011933:Reagent Kits, Diagnostic; D012015:Reference Standards; D012016:Reference Values; D015203:Reproducibility of Results; D016482:Urinalysis / Q000379:methods* / Q000592:standards; D055815:Young Adult; D001613:beta 2-Microglobulin / Q000652:urine*
chemical_list: D011933:Reagent Kits, Diagnostic; D001613:beta 2-Microglobulin; D003404:Creatinine