title: Analytical and clinical validation of the Immulite 1000 hCG assay for quantitative analysis in urine.
abstract: BACKGROUND
  The Siemens Immulite hCG assay detects all major hCG variants in serum. Currently, this assay is only FDA approved for qualitative measurement of hCG in urine.
  
  
  METHODS
  Complete validation of the hCG assay in urine was performed on the Siemens Immulite 1000 immunoassay platform. Reference intervals were established for females <55 y, females ≥55 y, and males 20-70 y.
  
  
  RESULTS
  The limit of quantitation was 2.0 IU/l. The Immulite hCG assay was precise for measuring hCG in urine from pregnant patients with intra- and inter-assay imprecision of <11% CV. The assay was linear over a dynamic range of 2-2600 IU/l and 2-3500 IU/l for hCG and hCGβ respectively. The assay was non-linear for hCGβcf. No hook effect was observed at concentrations up to 1,200,000 pmol/l, for hCGβ or hCGβcf. The reference intervals were <2.0 IU/l for males, <2.2I U/l for females <55 y, and <12.2I U/l for females ≥55 y.
  
  
  CONCLUSIONS
  The Immulite 1000 hCG assay can accurately quantify hCG in urine.
authors.affiliation: Department of Pathology, Microbiology, and Immunology, Vanderbilt University Medical Center, Nashville, TN 37232, United States.
authors.forename: Frances L
authors.initials: FL
authors.lastname: Cate
authors.forename: Courtney
authors.initials: C
authors.lastname: Moffett
authors.forename: Ann M
authors.initials: AM
authors.lastname: Gronowski
authors.forename: David G
authors.initials: DG
authors.lastname: Grenache
authors.forename: Katherine E
authors.initials: KE
authors.lastname: Hartmann
authors.forename: Alison
authors.initials: A
authors.lastname: Woodworth
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D006063:Chorionic Gonadotropin / Q000652:urine*; D005260:Female; D006801:Humans; D007118:Immunoassay; D057230:Limit of Detection; D008297:Male; D008875:Middle Aged; D011247:Pregnancy; D021122:Protein Subunits / Q000652:urine*; D012016:Reference Values; D012737:Sex Factors
chemical_list: D006063:Chorionic Gonadotropin; D021122:Protein Subunits