Prolonged steroid administration is a risk factor for exogenous Cushing syndrome. Endogenous (Cushing disease) is more common in women aged 20-40 and in the

 

 Risk factors for primary adrenal insufficiency

include human immunodeficiency virus (HN) infection,

metastatic cancer (lung, breast, leukemia), infection (bac ­

terial, fungal, viral, tuberculosis), sarcoidosis, or sepsis.

HIV infection results in adrenal insufficiency at a much

higher rate than in the general population. Up to 25o/o of

patients with HIV have inadequate adrenal reserves.

Contributing factors in HIV patients include the human

immunodeficiency virus itself, opportunistic infections,

and medications.

Secondary adrenal insufficiency is due to inadequate

production of ACTH from the pituitary gland. Cortisol

production is decreased; however, aldosterone secretion is

usually intact because its production is stimulated to a

• Adrenal crisis should be considered in the presence of

refractory hypotension.

• The preferred steroid for adrenal insufficiency is

dexamethasone because it does not interfere with the

cosyntropin stimulation test.

much greater extent by angiotensin. Suppression of the

hypothalamic-pituitary-adrenal axis by exogenous steroid

administration is the most common cause of adrenal

insufficiency. It is based on the dose and duration of

treatment. Administrations of steroids for <2 weeks or doses

<5 mg per day are unlikely to result in adrenal insufficiency.

Steroid administration (withdrawal), pituitary tumors, and

trauma place patients at risk for secondary adrenal

insufficiency.

Acute adrenal insufficiency (Addison or adrenal crisis)

is an emergent condition that occurs in a person who has

underlying adrenal suppression who undergoes an acute

stress or illness. Some patients have a history of chronic

adrenal insufficiency; for others, adrenal crisis is the initial

presentation.

Cushing syndrome refers to a situation in which there

is a symptomatic excess of glucocorticoids. Prolonged

exogenous administration of steroids is the most c ommon

cause of Cushing syndrome. Cushing disease is present

when Cushing syndrome is due to excessive ACTH

secretion from the pituitary gland. Endogenous Cushing

syndrome (Cushing disease) is much less common and

occurs in 13 per 1 million persons.

In addition to exogenous steroid administration,

Cushing syndrome is due to an ACTH-producing tumor

of the pituitary gland (70%), adrenal gland (15%), or

other (15%). Other tumors producing ACTH include

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ADRENAL EMERGENCIES

pancreatic cancer, small-cell lung carcinoma, and carcinoid tumors.

Prolonged steroid administration is a risk factor for

exogenous Cushing syndrome. Endogenous (Cushing

disease) is more common in women aged 20-40 and in the

presence of malignancy (lung, pancreatic).

CLINICAL PRESENTATION

� History

Patients with adrenal insufficiency r eport complaints of

fatigue, nausea, vomiting, abdominal pain, lighthead ­

edness, or diarrhea, whereas those with Cushing syndrome report fatigue, weakness, and menstrual

irregularities.

� Physical Examination

Patients with primary adrenal insufficiency will present

with hyperpigmentation of the skin due to increased levels

of circulating ACTH. This finding is present in 98% of

these patients. Acute adrenal insufficiency is characterized

by mental status changes, hypotension, and tachycardia.

Hypothermia may be present, but fever can be seen in the

setting of concurrent infection.

Physical findings in Cushing syndrome may include

truncal obesity, moon facies, buffalo hump, hirsutism, and

skin striae. Hypertension is a common finding.

DIAGNOSTIC STUDIES

� Laboratory

Laboratory studies in patients with suspected adrenal

insufficiency or Cushing syndrome should include complete

blood count, electrolytes with glucose, cortisol, and ACTH

level. In primary adrenal insufficiency, hyponatremia is

present in 90% of patients, hyperkalemia in 64%, and

hypercalcemia in 6-33%. In secondary adrenal insufficiency,

electrolyte abnormalities are less likely because aldosterone

production is not impaired. Anemia is present in 40% of

patients, and an elevated white blood cell count suggests

infection. Hypoglycemia is present in two thirds of patients.

A random serum cortisol level <15 mcg/dL in an

acutely ill patient is diagnostic of adrenal insufficiency in

most cases and can be performed in the emergency department (ED). An ACTH level can be drawn, but results are

rarely available in the ED.