The limited role of midnight salivary cortisol levels in the diagnosis of subclinical hypercortisolism in patients with adrenal incidentaloma.

From http://www.eje.org/cgi/content/abstract/EJE-08-0485v1

Benedetta Masserini, Valentina Morelli, Silvia Bergamaschi, Federica Ermetici, Cristina Eller-Vainicher, Anna Maria Barbieri, Antonia Maffini, Alfredo Scillitani, Bruno Ambrosi, P Beck-Peccoz and Iacopo Chiodini

B Masserini, Department of Medical Sciences, Endocrinology and Diabetology Unit, University of Milan, Fondazione Policlinico, I.R.C.C.S., Milano, Italy
V Morelli, Department of Medical Sciences, Endocrinology and Diabetology Unit, University of Milan, Fondazione Policlinico, I.R.C.C.S., Milano, Italy
S Bergamaschi, Department of Medical Sciences, Endocrinology and Diabetology Unit, University of Milan, Fondazione Policlinico, I.R.C.C.S., Milano, Italy
F Ermetici, Department of Medical and Surgical Sciences, Endocrinology Unit, Policlinico San Donato I.R.C.C.S, University of Milan, San Donato Milanese, Italy
C Eller-Vainicher, Department of Medical Sciences, Endocrinology and Diabetology Unit, University of Milan, Fondazione Policlinico, I.R.C.C.S., Milano, Italy
A Barbieri, Department of Medical Sciences, Endocrinology and Diabetology Unit, University of Milan, Fondazione Policlinico, I.R.C.C.S., Milan, Italy
A Maffini, Department of Medical Sciences, Endocrinology and Diabetology Unit, University of Milan, Fondazione Policlinico, I.R.C.C.S., Milano, Italy
A Scillitani, Unit of Endocrinology, Casa Sollievo della Sofferenza Scientific Institute, San Giovanni Rotondo, Italy
B Ambrosi, Department of Medical and Surgical Sciences, Endocrinology Unit, Policlinico San Donato I.R.C.C.S, University of Milan, San Donato Milanese, Italy
P Beck-Peccoz, Department of Medical Sciences, Endocrinology and Diabetology Unit, University of Milan, Fondazione Policlinico, I.R.C.C.S., Milano, Italy
I Chiodini, Department of Medical Sciences, Endocrinology and Diabetology Unit, University of Milan, Fondazione Policlinico, I.R.C.C.S., Milano, Italy

Correspondence: Benedetta Masserini, Email: benedetta.masserini@gmail.com

Abstract

Objective: The criteria for defining subclinical hypercortisolism (SH) are debated and a real gold standard test or combination of tests is lacking. Recently late night salivary cortisol (MSC) has been described as a sensitive and easy-to-perform marker for diagnosing overt hypercortisolism. No data are available on the role of MSC in the diagnosis of SH. The aim of the study was to evaluate the sensitivity and specificity of midnight salivary cortisol levels in the diagnosis of SH in patients with adrenal incidentalomas (AI).

Methods: In 103 (F/M 69/34) patients with AI, MSC levels were studied. One mg overnight dexamethasone suppression test (DST), urinary free cortisol (UFC) and ACTH plasma levels were also evaluated. Patients were defined as affected by SH if showed 2 of the following criteria: DST > 83 nmol/L, ACTH < 2.2 pmol/L, UFC > 193 nmol/24h.

Results: No difference in MSC levels in patients with SH (3.1±3.1nmol/L) compared with patients without SH (2.2±2.8 nmol/L) was observed. In patients with SH, MSC levels were significantly correlated with DST (R= 0.4, p < 0.05). Using the cut-off of 5.1 nmol/L the sensitivity and the specificity of MSC levels for diagnosis of SH is 22.7% and 87.7% respectively.

Conclusion: In patients with AI normal levels of MSC do not exclude SH whereas high levels may suggest the presence of SH identified by conventional tests. Thus MSC is not suitable as screening test, although it may be used in conjunction with other tests as confirming test in selected patients.