The diagnostic value of salivary cortisol and salivary cortisone in patients with suspected hypercortisolism

Primary Hypercortisolism

Primary hypercortisolism, commonly known as Cushing's syndrome, is an endocrine disorder characterized by excessive cortisol production by the adrenal glands, independent of adrenocorticotropic hormone stimulation. This disorder presents with a wide range of clinical manifestations, including metabolic, cardiovascular, and psychological disturbances, making its diagnosis and management complex. This document aims to provide a detailed review of primary hypercortisolism, including its pathophysiology, clinical presentation, diagnostic approaches, and treatment modalities. Special attention is given to the molecular mechanisms underlying cortisol overproduction, differential diagnosis from other forms of Cushing's syndrome, and the challenges posed by this condition in clinical practice.

Neoplastic hypercortisolism: Cut-off values for late-night salivary cortisol & cortisone

OBJECTIVES

One of the recommended initial tests for diagnosing neoplastic hypercortisolism is the measurement of late-night salivary cortisol (CortisolLNSa). Published cut-off values for CortisolLNSa and late-night salivary cortisone (CortisoneLNSa) vary widely between studies. This study aims to establish cut-off values for CortisolLNSa and CortisoneLNSa using liquid chromatography-tandem mass spectrometry and to determine which salivary hormone performs better in distinguishing between people with and without neoplastic hypercortisolism.

METHODS

A retrospective study was conducted on subjects screened for endogenous hypercortisolism at Amsterdam UMC between December 2015 and February 2022. 25 subjects with and 430 subjects without neoplastic hypercortisolism were included. The diagnosis neoplastic hypercortisolism was confirmed by histology and postoperative clinical features, not on biochemical tests, and excluded based on a follow-up of at least 12 months without progressive clinical signs of neoplastic hypercortisolism. Salivary samples were collected between 22:00-23:59 h and CortisolLNSa and CortisoneLNSa concentrations were measured using liquid chromatography-tandem mass spectrometry.

RESULTS

The median CortisolLNSa was 7.8 nmol/L for subjects with and 0.8 nmol/L for subjects without neoplastic hypercortisolism (p < 0.001). The median CortisoneLNSa was 35.5 nmol/L and 5.3 nmol/L, respectively (p < 0.001). Optimal diagnostic accuracy was established at 2.25 nmol/L for CortisolLNSa (sensitivity 92 %, specificity 89 %, positive predictive value 32.9 %, negative predictive value 99.5 %) and 15.5 nmol/L for CortisoneLNSa (sensitivity 93.8 %, specificity 94.5 %, positive predictive value 46.9 %, negative predictive value 99.7 %).

CONCLUSIONS

We established cut-off values for CortisolLNSa and CortisoneLNSa for the diagnosis of neoplastic hypercortisolism. CortisoneLNSa provided the highest diagnostic accuracy and we therefore recommend it as the preferred salivary measurement.

An LC-MS/MS-based method for the simultaneous quantification of melatonin, cortisol and cortisone in saliva

Disturbances in the diurnal pattern are associated with several clinical and psychological conditions, including depression and fatigue. Salivary sampling for melatonin, cortisol and cortisone provides a non-invasive method for frequent sampling and obtaining biochemical insight into the diurnal pattern of individuals. Therefore, a new liquid chromatography-tandem mass spectrometry-based method for the measurement of salivary melatonin, cortisol and cortisone was developed and validated. The method required 250 μl saliva, used isotope dilution methodology and was based on a liquid-liquid extraction for sample preparation, reversed-phase chromatography and multiple reaction monitoring on a mass spectrometer for quantitation. The lower limits of quantification obtained were 0.010 nmol/L for melatonin, 0.5 nmol/L for cortisol and 1.00 nmol/L for cortisone and the limits of detection were 0.003 nmol/L, 0.15 nmol/L and 0.1 nmol/L respectively. The method imprecision was ≤14% for all measurands, and the method comparison showed highly comparable results with high correlation coefficients (all ≥0.964). Potential interference of cortisol and cortisone by prednisolone was observed and could be detected by chromatogram review. Typical diurnal patterns for melatonin, cortisol and cortisone were observed in the saliva of 20 cancer survivors who collected saliva throughout the day.

Salivary cortisol and cortisone in diagnosis of Cushing's syndrome - a comparison of six different analytical methods

OBJECTIVES

Salivary cortisol and cortisone at late night and after dexamethasone suppression test (DST) are increasingly used for screening of Cushing's syndrome (CS). We aimed to establish reference intervals for salivary cortisol and cortisone with three liquid chromatography-tandem mass spectrometry (LC-MS/MS) techniques and for salivary cortisol with three immunoassays (IAs), and evaluate their diagnostic accuracy for CS.

METHODS

Salivary samples at 08:00 h, 23:00 h and 08:00 h after a 1-mg DST were collected from a reference population (n=155) and patients with CS (n=22). Sample aliquots were analyzed by three LC-MS/MS and three IA methods. After establishing reference intervals, the upper reference limit (URL) for each method was used to calculate sensitivity and specificity for CS. Diagnostic accuracy was evaluated by comparing ROC curves.

RESULTS

URLs for salivary cortisol at 23:00 h were similar for the LC-MS/MS methods (3.4-3.9 nmol/L), but varied between IAs: Roche (5.8 nmol/L), Salimetrics (4.3 nmol/L), Cisbio (21.6 nmol/L). Corresponding URLs after DST were 0.7-1.0, and 2.4, 4.0 and 5.4 nmol/L, respectively. Salivary cortisone URLs were 13.5-16.6 nmol/L at 23:00 h and 3.0-3.5 nmol/L at 08:00 h after DST. All methods had ROC AUCs ≥0.96.

CONCLUSIONS

We present robust reference intervals for salivary cortisol and cortisone at 08:00 h, 23:00 h and 08:00 h after DST for several clinically used methods. The similarities between LC-MS/MS methods allows for direct comparison of absolute values. Diagnostic accuracy for CS was high for all salivary cortisol and cortisone LC-MS/MS methods and salivary cortisol IAs evaluated.