Clinical Endocrinology-Time for a Reset?

Abstract

Measurement of blood levels of circulating hormones has always been the cornerstone of the biochemical diagnosis of endocrine diseases, with the objective of detecting hormone excess or insufficiency. Unfortunately, the dynamic nature of hormone secretion means single-point measurements of many hormones often lack diagnostic validity. Endocrinologists have devised complex dynamic tests as indirect assessments of the functioning of the hormone system under investigation. Recent advances in the measurement of dynamic hormone changes across the day now offer an opportunity to reconsider whether there might be better ways both to diagnose and to monitor the therapy of endocrine conditions.

Keywords: Addison’s; Cushing’s; glucocorticoids; hyperaldosteronism; rhythms; stress.

Figure 1.

Panel (A) (from the Ultradian Consortium, see [9]), and panel (B) (unpublished data Saevik and Husebye) demonstrate the daily profile of 2 individuals with long-standing Addison’s disease on hydrocortisone (A) (compared with data from 214 normal controls [9]) or cortisone acetate (B) replacement. Note the interindividual differences in morning cortisol—The subject in (A) has severe morning hypocortisolaemia, while, despite a flat synacthen test, the patient in (B) shows an endogenous morning increase in cortisol circled in red. Panel (C) (unpublished data from Fudulu et al see [8]) shows the dynamic changes in cortisol and cortisone during and following open heart surgery for a Glenn shunt in an infant of 1 year 2 months. Note the delayed hypothalamic-pituitary-adrenal activation presumably related to the inflammatory response to sternotomy rather than the operative process itself.