Rahel M Büttler1, Frans Martens1, Mariëtte T Ackermans2, Andrew S Davison3, Antonius E van Herwaarden4, Linda Kortz5, Johannes G Krabbe6, Eef G W Lentjes7, Charlotte Syme8, Rachel Webster9, Marinus A Blankenstein1, Annemieke C Heijboer10. 1. Department of Clinical Chemistry, Endocrine Laboratory, VU University Medical Center, Amsterdam, The Netherlands. 2. Department of Clinical Chemistry, Laboratory of Endocrinology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands. 3. Department of Clinical Biochemistry and Metabolic Medicine, Liverpool Clinical Laboratories, Royal Liverpool and Broadgreen University Hospitals Trust, Liverpool, United Kingdom. 4. Department of Laboratory Medicine, Radboud University Medical Centre, Nijmegen, The Netherlands. 5. MVZ wagnerstibbe für Laboratoriumsmedizin, Gynäkologie, Humangenetik und Pathologie GmbH, Göttingen, Germany. 6. Department of Clinical Chemistry and Laboratory Medicine, Medical Spectrum Twente, Medlon BV, The Netherlands. 7. Department of Clinical Chemistry & Haematology, University Medical Center, Utrecht, The Netherlands. 8. Department of Clinical Biochemistry, Glasgow Royal Infirmary, Glasgow, United Kingdom. 9. Department of Clinical Biochemistry, University Hospitals Birmingham NHS Foundation Trust Queen Elizabeth Hospital, Birmingham, United Kingdom. 10. Department of Clinical Chemistry, Endocrine Laboratory, VU University Medical Center, Amsterdam, The Netherlands. Electronic address: a.heijboer@vumc.nl.
Abstract
BACKGROUND: Liquid-chromatography tandem mass spectrometry (LC-MS/MS) has become the method of choice in steroid hormone measurement. However, little information on the mutual agreement of LC-MS/MS methods is available. We compared eight routine unpublished LC-MS/MS methods for the simultaneous measurement of testosterone and androstenedione. METHODS: Sixty random serum samples from male and female volunteers were analysed in duplicate by eight routine LC-MS/MS methods. We performed Passing-Bablok regression analyses and calculated Pearson's correlation coefficients to assess the agreement of the methods investigated with one published method known to be accurate. Intra-assay CV of each method was calculated from duplicate results, recoveries for each method were calculated from six spiked samples. Furthermore, a CV between the investigated methods was calculated. RESULTS: The concentrations ranged from 0.05-1.26 nmol/L, 6.15-24.44 nmol/L and 0.15-4.78 nmol/L for testosterone in females, testosterone in males and androstenedione, respectively. The intra-assay CVs were between 3.7-16.0%, 0.9-5.2% and 1.2-9.5% for testosterone in females, testosterone in males and androstenedione, respectively. The slopes of the regression lines ranged between 0.90-1.25, 0.87-1.24 and 0.94-1.31 for testosterone concentrations in females, all testosterone values and androstenedione, respectively. Inter-method CVs were 24%, 14% and 29% for testosterone for concentrations in females and males and androstenedione, respectively. These compare unfavourably to the variation found earlier in published methods. CONCLUSION: Although most routine LC-MS/MS methods investigated here showed a reasonable agreement, some of the assays showed a high variation. The observed differences in standardization should be taken into account when applying reference values, or should, preferably, be solved.
BACKGROUND: Liquid-chromatography tandem mass spectrometry (LC-MS/MS) has become the method of choice in steroid hormone measurement. However, little information on the mutual agreement of LC-MS/MS methods is available. We compared eight routine unpublished LC-MS/MS methods for the simultaneous measurement of testosterone and androstenedione. METHODS: Sixty random serum samples from male and female volunteers were analysed in duplicate by eight routine LC-MS/MS methods. We performed Passing-Bablok regression analyses and calculated Pearson's correlation coefficients to assess the agreement of the methods investigated with one published method known to be accurate. Intra-assay CV of each method was calculated from duplicate results, recoveries for each method were calculated from six spiked samples. Furthermore, a CV between the investigated methods was calculated. RESULTS: The concentrations ranged from 0.05-1.26 nmol/L, 6.15-24.44 nmol/L and 0.15-4.78 nmol/L for testosterone in females, testosterone in males and androstenedione, respectively. The intra-assay CVs were between 3.7-16.0%, 0.9-5.2% and 1.2-9.5% for testosterone in females, testosterone in males and androstenedione, respectively. The slopes of the regression lines ranged between 0.90-1.25, 0.87-1.24 and 0.94-1.31 for testosterone concentrations in females, all testosterone values and androstenedione, respectively. Inter-method CVs were 24%, 14% and 29% for testosterone for concentrations in females and males and androstenedione, respectively. These compare unfavourably to the variation found earlier in published methods. CONCLUSION: Although most routine LC-MS/MS methods investigated here showed a reasonable agreement, some of the assays showed a high variation. The observed differences in standardization should be taken into account when applying reference values, or should, preferably, be solved.
Authors: Lennart J van Winden; Ravi F M Vermeulen; Vincent van den Noort; Katja N Gaarenstroom; Gemma G Kenter; Monique M A Brood-van Zanten; Catharina M Korse; Marc van Beurden; Huub H van Rossum Journal: J Endocr Soc Date: 2022-04-25