Background: Diagnosis and treatment guidelines of men with adult-onset testosterone deficiency (TD) were published by the British Society for Sexual Medicine (2017). Laboratory practice has a major role in supporting these with accurate and precise total testosterone (TT) methods and standardised pre- and post-analytical protocols.
Objective: Our study investigated whether laboratory practice supported management guidelines of adult-onset TD.
Methods: A representative internet-based questionnaire-survey of senior laboratory scientists (UK/Republic of Ireland) was conducted (AprilMay 2018). Questions reflected sampling, general laboratory practice, reference ranges and reporting of results. The results were analysed in conjunction with data obtained from the National External Quality Assurance Service (UK NEQAS) on assay performance.
Results: Analyses of 96 questionnaires returned the following: 74 laboratories stated that optimal sampling time was communicated to users; 81 laboratories used immunoassays; 76 laboratories included reference ranges for adult men (31 had dual/multiple age-related intervals). Wide variability in lower/upper limits was evident in the common immunoassays; the majority of reference ranges were from manufacturers (50.0%) or historical (18.8%). Action limits based on TT levels were used by 64 laboratories, but 63 did not report a borderline range as suggested by guidelines. Protocols for cascading tests based on TT were evident in 58 laboratories, with 50 laboratories offering calculated free testosterone; Interpretative comments were provided by 67 laboratories, but no references were made to management guidelines. Data from UK NEQAS demonstrated considerable variation in testosterone assay performance.
Conclusions: Clinicians in all areas, and particularly in Primary Care, require clearer guidance from laboratories in the interpretation of androgen status in men. Our results reinforce an urgent requirement for action regarding standardisation and harmonisation of testosterone assays and laboratory function.