Víctor González-Sánchez1, Oscar Moreno-Pérez2, Luis García de Guadiana3, Pedro Sánchez-Pellicer4, Rocío Alfayate5, Montserrat Mauri5, José Sánchez-Payá6, Antonio Picó1. 1. Endocrinology and Nutrition Department, Hospital General Universitario de Alicante, Universidad Miguel Hernández, Alicante, Spain. 2. Endocrinology and Nutrition Department, Hospital General Universitario de Alicante, Universidad Miguel Hernández, Alicante, Spain. Electronic address: omoreno@umh.es. 3. Clinical Analysis Department, Hospital Universitario Santa Lucía, Cartagena, Murcia, Spain. 4. Clinical Analysis Department, Hospital del Vinalopó, Elche, Alicante, Spain. 5. Hormone Laboratory, Hospital General Universitario de Alicante, Alicante, Spain. 6. Preventive Medicine Department, Hospital General Universitario de Alicante, Universidad Miguel Hernández, Alicante, Spain.
Abstract
BACKGROUND AND AIMS: The interassay variability found in the measurement of testosterone (T) levels warrants the need for laboratories to validate their methods to establish trustworthy cut-off points for diagnosis of male hypogonadism. The aims of this study were to validate measurement of total T (TT) at our laboratory in order to obtain reference ranges for TT, calculated free T (CFT), calculated bioavailable T (CBT), and salivary T (ST) in healthy young men from the Mediterranean region, and to evaluate the potential clinical value of ST by establishing its correlation with serum T. METHODS: An observational, cross-sectional study with sequential sampling. INCLUSION CRITERIA: men aged 18-30 years with body mass index (BMI)<30. EXCLUSION CRITERIA: chronic diseases, hepatic insufficiency or use of drugs altering circulating T levels. Main outcome measures TT (chemiluminescent immunoassay UniCell DXI 800 [Access T Beckman Coulter]), CFT and CBT (Vermeulen's formula), and ST (radioimmunoassay for serum TT modified for saliva [Coat-A-Count, Siemens]). Descriptive statistical analyses and correlation by Spearman's rho (SPSS 19.0 Inc., Chicago) were used. RESULTS: One hundred and twenty-one subjects aged 24±3.6 years with BMI 24±2.5 kg/m(2) were enrolled. Hormone study: TT, 19±5.5 nmol/L (reference range [rr.] 9.7-33.3); CFT, 0.38 nmol/L (rr. 0.22-0.79); CBT, 9.7 nmol/L (rr. 4.9-19.2); and ST, 0.35 nmol/L (rr. 0.19-0.68). Correlation between ST and CFT was 0.46. CONCLUSIONS: In men from the Mediterranean region, values of TT>9.7 nmol/L, CFT>0.22 nmol/L, and/or CBT>4.9 nmol/L make the presence of biochemical hypogonadism unlikely. According to the correlation between serum and ST, the clinical value of ST remains to be established.
BACKGROUND AND AIMS: The interassay variability found in the measurement of testosterone (T) levels warrants the need for laboratories to validate their methods to establish trustworthy cut-off points for diagnosis of male hypogonadism. The aims of this study were to validate measurement of total T (TT) at our laboratory in order to obtain reference ranges for TT, calculated free T (CFT), calculated bioavailable T (CBT), and salivary T (ST) in healthy young men from the Mediterranean region, and to evaluate the potential clinical value of ST by establishing its correlation with serum T. METHODS: An observational, cross-sectional study with sequential sampling. INCLUSION CRITERIA: men aged 18-30 years with body mass index (BMI)<30. EXCLUSION CRITERIA: chronic diseases, hepatic insufficiency or use of drugs altering circulating T levels. Main outcome measures TT (chemiluminescent immunoassay UniCell DXI 800 [Access T Beckman Coulter]), CFT and CBT (Vermeulen's formula), and ST (radioimmunoassay for serum TT modified for saliva [Coat-A-Count, Siemens]). Descriptive statistical analyses and correlation by Spearman's rho (SPSS 19.0 Inc., Chicago) were used. RESULTS: One hundred and twenty-one subjects aged 24±3.6 years with BMI 24±2.5 kg/m(2) were enrolled. Hormone study: TT, 19±5.5 nmol/L (reference range [rr.] 9.7-33.3); CFT, 0.38 nmol/L (rr. 0.22-0.79); CBT, 9.7 nmol/L (rr. 4.9-19.2); and ST, 0.35 nmol/L (rr. 0.19-0.68). Correlation between ST and CFT was 0.46. CONCLUSIONS: In men from the Mediterranean region, values of TT>9.7 nmol/L, CFT>0.22 nmol/L, and/or CBT>4.9 nmol/L make the presence of biochemical hypogonadism unlikely. According to the correlation between serum and ST, the clinical value of ST remains to be established.