Oral Presentation ESA-SRB-AOTA 2019

Comparison between liquid chromatography-mass spectrometry and immunoassay in the measurement of serum testosterone in adult men at PathWest, Sir Charles Gairdner Hospital (#96)

Sharon Lam 1 , Conchita Boyder 2 , Bronwyn Stuckey 1 2 3 , Ee Mun Lim 1 2
  1. Sir Charles Gairdner Hospital, East Perth, WA, Australia
  2. Clinical Biochemistry, Pathwest, Perth, WA, Australia
  3. Keogh Institute for Medical Research, Perth, WA, Australia

Introduction

Androgen deficiency in adult men is characterised by clinical features of hypogonadism and confirmed by low morning serum total testosterone (T)[i]. Hence, accurate determination of T is essential.

Immunoassay technique (IAT) is used in T measurement as it is economical and provides rapid information. IAT can reliably measure T at higher levels, but is less accurate at lower levels, in infants, children and women. The ratio 10:1 of T:dihydrotestosterone (DHT) was established using radioimmunoassay (RIA).

Currently, mass spectrometry (LCMS) is preferred given better accuracy and less variability compared to IAT[ii] [iii] [iv]. However, there is operator and inter-method variability affecting precision and accuracy[v]. It is also labour intensive and therefore costlier with longer processing times.

Therefore, there is debate whether IAT is preferred in measuring T in adult men[vi].

Methods

Primary: Retrospective audit comparing T measured by LCMS and IAT in men >17 years (n=49), from February 2016 to August 2018.

Secondary: We compared T:DHT relationship using LCMS (n=81). Samples from men (n=8) on testosterone replacement were excluded.

Results

T measured using LCMS and IAT demonstrated good correlation (R2=0.9758). Even when T<10 nmol/L, this relationship was maintained.

Relationship between LCMS T and DHT showed only 27% (n=22) had a ratio of approximately 10:1, with poor correlation (R2 =0.6932).

Conclusion

Given good correlation between LCMS and IAT (even when T<10 nmol/L), quicker processing and lower costs, IAT could be considered as first line method in measuring T in adult men. Relationship between T and DHT established using RIA was not observed with LCMS. Larger studies to further validate T measurement using IAT in adult males are recommended.

 

 

  1. [i] (Frederick C.W. Wu 2010)
  2. [ii] (Christina Wang 1 February 2004)
  3. [iii](ValérieMoalElisabethMathieuPascalReynierYvesMalthièryYvesGallois November–December 2007)
  4. [iv] (Joëlle Taieb July 2003)
  5. [v] (Yuesong Wang 2014)
  6. [vi] (Huhtaniemi IT1 and Group. June 2012)