Cushing's syndrome
The case
A 16-year-old girl with no significant past medical history presents with several months of nonspecific symptoms (lol). Her pediatrician did some labs and sent her to the Emergency Department when they resulted:
In the Emergency Department, she was noted to be mildly hypertensive (SBP 130s-150s), had moon facies, hirsutism, and abdominal striae (no joke!). Personal and family histories were otherwise noncontributory.
We (meaning the astute resident) suspected Cushing's Syndrome... now what? We know the syndrome results from excess cortisol production, but how or why should that prompt us to do a workup?
The brush up
First things first - ensure there are no exogenous glucocorticoids. Then, think about the differential for Cushing's Syndrome (i.e. ACTH-dependent vs ACTH-independent conditions):
- ACTH-dependent is almost always Cushing's disease caused by a pituitary tumor
- ACTH-independent is most commonly iatrogenic/factitious followed by adrenal tumors
Also, think about the differential for pseudo-Cushing's Syndrome:
- metabolic syndrome
- PCOS
- visceral obesity
- alcoholism
- anorexia nervosa
- depression
The conclusion
The patient's case was discussed with an endocrinologist who arranged next-day follow up for specialized testing. Her random cortisol level was 18.3 (normal range 4-24), and her ACTH was 21.3 (normal range 10-60). FSH/LH were normal. Electrolytes and blood gas were within acceptable limits. Her working diagnosis at the time of discharge from the ED was new onset diabetes with associated metabolic syndrome.
References:
1. Guaraldi F and Salvatori R. Cushing Syndrome: Maybe Not So Uncommon of an Endocrine Disease. J Am Board Fam Med March-April 2012;25(2 199-208.
2. Chanson P and Salenave S. Metabolic Syndrome in Cushing's Syndrome. Neuroendocrinology 2010;92 Suppl 1:96-101.
3. Tang A, O'Sullivan A, et al. Psychiatric Symptoms as a Clinical Presentation of Cushing's Syndrome. An Gen Psych 2013;12(23).