Salivary corticosteroids in the study of adrenal function

Area of Science:

• Endocrinology
• Biochemistry
• Clinical Diagnostics

Background:

• Assessing adrenal gland function is crucial for diagnosing endocrine disorders.
• Plasma corticosteroids (PCC) are commonly used, but salivary corticosteroids (SCC) offer a non-invasive alternative.
• Understanding the comparative utility of SCC and PCC in various physiological and pathological states is important.

Purpose of the Study:

• To compare the diagnostic utility of salivary corticosteroids (SCC) and plasma corticosteroids (PCC).
• To evaluate SCC and PCC under basal conditions, dexamethasone suppression, and ACTH stimulation.
• To determine if SCC can effectively differentiate normal adrenal function from hypercortisolism.

Main Methods:

• Salivary and plasma corticosteroids were measured using a non-extraction radioimmunoassay (RIA) method.
• Studies included a reference group, patients with non-adrenal pathology, and patients with hypercortisolism.
• Tests involved basal measurements, dexamethasone (DXM) suppression, and ACTH stimulation.

Main Results:

• SCC and PCC showed similar patterns in circadian rhythm and DXM suppression in healthy individuals.
• Salivary corticosteroid responsiveness to ACTH stimulation was approximately double that of plasma.
• In hypercortisolism, SCC demonstrated closer agreement with adrenal hyperfunction than PCC.

Conclusions:

• Salivary corticosteroids (SCC) are as effective, or potentially better than, plasma corticosteroids (PCC) in distinguishing normal adrenal function from hyperfunction.
• SCC correlate more closely with the clinical symptoms of adrenal hyperfunction than PCC.
• The ACTH stimulation test yields significantly higher responses when using SCC compared to PCC.