Biochemical diagnosis of adrenal insufficiency: the added value of dehydroepiandrosterone sulfate measurements.
OBJECTIVE
To review biochemical tests used in establishing the challenging diagnosis of adrenal insufficiency.


METHODS
We reviewed the relevant literature, including our own data, on various biochemical tests used to determine adrenal function. The advantages and limitations of each approach are discussed.


RESULTS
Baseline measurements of serum cortisol are helpful only when they are very low (≤ 5 μg/dL) or clearly elevated, whereas baseline plasma adrenocorticotropic hormone levels are helpful only when primary adrenal insufficiency is suspected. Measurements of baseline serum dehydroepiandrosterone sulfate (DHEA-S) levels are valuable in patients suspected of having adrenal insufficiency. Although serum DHEA-S levels are low in patients with primary or central adrenal insufficiency, a low level of this steroid is not sufficient by itself for establishing the diagnosis. A normal age- and sex-adjusted serum DHEA-S level, however, practically rules out the diagnosis of adrenal insufficiency. Many patients require dynamic biochemical studies, such as the 1-μg cosyntropin test, to assess adrenal function.


CONCLUSIONS
In establishing the diagnosis of central adrenal insufficiency, we recommend measurements of baseline serum cortisol and DHEA-S levels. In addition to these, determination of plasma levels of aldosterone, adrenocorticotropic hormone, and renin activity is necessary when primary adrenal insufficiency is suspected. With a random serum cortisol level of ≥ 12 μg/dL in the ambulatory setting or a normal age- and sex-adjusted DHEA-S level (or both), the diagnosis of adrenal insufficiency is extremely unlikely. When serum DHEA-S levels are low or equivocal, however, dynamic testing will be necessary to determine hypothalamic-pituitary-adrenal axis function.
Division of Clinical and Molecular Endocrinology, Louis Stokes Cleveland Veterans Medical Center, University Hospitals Case Medical Center, Case Western Reserve University, Cleveland, Ohio, USA.
Ribal
R
Al-Aridi
Dima
D
Abdelmannan
Baha M
BM
Arafah
D000309:Adrenal Insufficiency / Q000097:blood* / Q000175:diagnosis*; D000324:Adrenocorticotropic Hormone / Q000097:blood; D019314:Dehydroepiandrosterone Sulfate / Q000097:blood*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood
D019314:Dehydroepiandrosterone Sulfate; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone