title: A single-centre evaluation of two new anti-Mullerian hormone assays and comparison with the current clinical standard assay.
abstract: OBJECTIVE
  Are the new Ansh Labs Ultra-Sensitive anti-Müllerian hormone (AMH) and picoAMH ELISA assays suitable for clinical use and is the Ultra-Sensitive assay comparable to the Beckman Coulter AMH Gen II assay?
  
  
  CONCLUSIONS
  The Ultra-Sensitive assay appears to have different calibration to the Gen II assay, but has performance characteristics generally suitable for clinical use.
  
  
  BACKGROUND
  The Gen II assay is the most commonly used AMH assay in routine biochemistry at present, but persistent calibration/interference problems have been reported.
  
  
  METHODS
  Serum from patients referred for AMH measurement was assayed (in duplicate) using the Gen II assay in Glasgow Royal Infirmary between January and February 2013. We randomly selected 193 stored serum samples to re-run (in duplicate) using the Ultra-Sensitive AMH Ansh Labs assay, blinded to the original result. Samples that returned low results were run on the picoAMH Ansh Labs assay. Performance characteristics and linearity of the new assays were also assessed.
  
  
  METHODS
  All serum samples from patients referred for AMH at Glasgow Royal Infirmary between January and February 2013 were eligible for inclusion. Investigators were blinded to any identifiable information regarding the patients, including sex, age and reason for AMH measurement.
  
  
  RESULTS
  Intra-assay and inter-assay coefficients of variation of the Ultra-Sensitive and picoAMH assays were ≤6.0 and ≤10.7%, respectively, over a range of concentrations. The assays had mean linearity of 98 and 97% over the dilution range of 1:2-1:16 and 1:2-1:8, respectively. The limit of detection of the ultrasensitive assay was calculated to be 0.34 pmol/l. For 166 samples which provided a quantitative result on the Gen II and Ultra-Sensitive Ansh Labs assays, the median (interquartile range) was 12.2 (3.4-29.3) pmol/l and 20.0 (6.6-36.8) pmol/l, respectively (P<0.0001). The Passing-Bablok regression equation (in pmol/l) was y (Ultra-Sensitive) = 1.7 + 1.4 × Gen II. More samples were below the clinical cut-off of 5.4 pmol/l using the Gen II assay (a difference between paired proportions of 15.0%, P < 0.001). Fifteen of the 22 undetectable samples yielded a measurable concentration result on the picoAMH assay.
  
  
  CONCLUSIONS
  The present study is a pragmatic assessment of the new assay under ideal conditions. Lot-to-lot variation could not be assessed. Demographics and outcomes of patients referred for AMH measurement were not known.
  
  
  CONCLUSIONS
  The Ansh Labs Ultra-Sensitive assay performance characteristics are similar to the Gen II assay and may be suitable for clinical and epidemiological use. Enhanced sensitivity of the Ansh Labs picoAMH assay enables measurement of low AMH concentrations. These results re-emphasize the need for an AMH international standard.
  
  
  BACKGROUND
  Ansh Labs provided kits for this study free of charge. The manufacturer played no part in conducting assays or data analysis. S.M.N. has received speaker's fees and participated in advisory boards for Beckman Coulter, Merck Serono, MSD and Ferring regarding AMH. P.W. is supported by British Heart Foundation fellowship FS/12/62/29889. We declare no other financial relationship or competing interests.
authors.affiliation: Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, UK.
authors.forename: Paul
authors.initials: P
authors.lastname: Welsh
authors.forename: Karen
authors.initials: K
authors.lastname: Smith
authors.forename: Scott M
authors.initials: SM
authors.lastname: Nelson
mesh_terms: D054304:Anti-Mullerian Hormone / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D012680:Sensitivity and Specificity
chemical_list: D054304:Anti-Mullerian Hormone
keywords: AMH; anti-Mullerian hormone; immunoassay; ovarian reserve; validation studies