An accurate, non-invasive approach to diagnose Cushing’s syndrome in at-risk populations

Background: The prevalence of Cushing’s syndrome (CS) in at-risk populations in developing countries remains uncertain. Evening urinary cortisol (UFC22–23) and salivary cortisol after treatment with 1-mg DST (SAFdex) have seldom been used as diagnostic tools in these populations. Objectives: (1) To establish the prevalence of CS in adults with cortisol-related morbidities using UFC22–23 and SAFdex as markers along with all first-line diagnostic tests recommended for CS; and (2) to assess the performance of each test and define a non-invasive diagnostic approach for CS in at-risk outpatient subjects. Methods: A total of 128 outpatients were evaluated, including type 1 and 2 diabetic patients with poor metabolic control (DM1 and DM2), hypertensive subjects with central obesity (HBP) and premenopausal women with osteoporosis (OS). Controls included 100 healthy volunteers and 23 patients with CS. Total urinary cortisol (UFC), UFC22–23, late-night salivary cortisol (SAF23) and suppression of cortisol levels in saliva (SAFdex) and serum (Fdex) after treatment with 1-mg DST were assessed. Results: CS was diagnosed in one DM2 and one HBP patient; both women exhibited central obesity. Among CS patients, UFC showed more within-person variability than UFC22–23 or SAF23. UFC22–23 and SAF23 were positively and significantly correlated in all groups (r ⩾ 0.70; p ⩽ 0.0001). UFC22–23 > 44.0 ng/mg creatinine or SAF23 > 3.8 nM were 100% sensitive (S) and specific (E) for CS. Furthermore, SAFdex > 2.0 nM or Fdex > 50.0 nM were 100% S and 97.3% E for CS. Conclusion: CS was diagnosed in 1.5% of at-risk patients. The combination of UFC22–23 or SAF23 with SAFdex offers a non-invasive diagnostic tool to assess cortisol nadir and feed-back status in outpatients.Fil: Cardoso, Estela M.del Lujan. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Investigaciones Medicas; Argentina. Universidad de Buenos Aires. Facultad de Odontología; ArgentinaFil: Arregger, Alejandro Luis. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Monardes, Gloria. Universidad de Buenos Aires. Facultad de Odontología; ArgentinaFil: Contreras, Liliana Noemi. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Investigaciones Medicas; Argentina. Universidad de Buenos Aires. Facultad de Odontología; Argentin

Salivary testosterone for the diagnosis of androgen deficiency in end-stage renal disease

BACKGROUND: Hypogonadism is frequent in patients with end-stage renal disease (ESRD). Salivary testosterone (Sal-T) is a non-invasive tool to screen androgen deficiency in adult male with normal renal function. However, available data on its utility in ESRD are not conclusive. OBJECTIVES: The objectives of the study were: (i) to compare free testosterone fractions in saliva (SAL-T) and serum (Free-T); (ii) to establish the correlation of Sal-T with circulating total (TT) and bioavailable testosterone (Bio-T); (iii) to detect androgen deficiency through SalT; (iv) to determine the correlation of Sal-T with clinical parameters. METHODS: The study included: 60 adult ESRD men on haemodialysis (20–60 years old) with decreased libido referred from two dialysis centres; 112 eugonadic and 40 hypogonadic adult men with normal renal function as controls. Simultaneous morning saliva and serum samples were obtained for testosterone measurements by liquid RIA (SAL-T; TT). Free-T and Bio-T were calculated by the Vermeulen equation. RESULTS: Sal-T (0.338 ± 0.177 nM) and Free-T (0.338 ± 0.165 nM) did not differ (P > 0.900) in ESRD as well as in control (0.337 ± 0.182 and 0.337 ± 0.172 nM, respectively; P > 0.900). Sal-T levels correlated positively (P < 0.0001) with Free-T (r = 0.95), TT (r = 0.80) and Bio-T (r = 0.76) in ESRD. Sal-T negatively correlated with age and years on dialytic therapy. Sal-T showed 100% sensitivity and specificity to differentiate patients with androgen deficiency (22%) from those with normal androgen levels (78%). Hypogonadism was hypergonadotrophic in 69% cases and hypogonadotrophic in 31%. CONCLUSIONS: These data demonstrate the value of morning Sal-T testing as a non-invasive approach to screen androgen status in ESRD patients.Fil: Cardoso, Estela M.del Lujan. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentina. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Investigaciones Medicas; ArgentinaFil: Contreras, Liliana. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Investigaciones Medicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Tumilasci, Elida G.. Universidad de Buenos Aires. Facultad de Medicina; ArgentinaFil: Elbert, Alicia. Centro de Estudios Renales e Hipertención Arterial; ArgentinaFil: Aguirre, Elvira C.. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; ArgentinaFil: Aquilano, Daniel R.. Instituto de Análisis Bioquímicos de Endodrinología; ArgentinaFil: Arregger, Alejandro Luis. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Houssay. Instituto de Investigaciones Medicas; Argentina. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Médicas; Argentin