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ment of a sense of well-being may be attributed to
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agent with potent glucocorticoid and mineralocorti- tion. Which tests are appropriate for screening?
coid activity, making it inappropriate to use in
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60 Adrenocortical Hormones and Drugs Affecting the Adrenal Cortex 703
Case Study Diagnosis and Treatment of Cushing s Disease
ulie Singer is a 55-year-old white woman who amethasone. Inferior petrosal sinus sampling pro-
Jwas admitted to the emergency department in vided a final confirmation of the diagnosis. The pa-
acute distress. A previous physical examination tient was prescribed metyrapone 2 g/day and
showed hypertension and diabetes mellitus type 2. aminoglutethimide 500 mg/day. Hyponatremia and
The patient s present medications include enalapril hyperkalemia required the concomitant administra-
40 mg, nifedipine 60 mg, and 100 U insulin. A physi- tion of a mineralocorticoid, fludrocortisone acetate
cal examination revealed prominent ankle edema, a 0.1 mg/day. With this treatment regimen, the pa-
palpable spleen, and hepatomegaly. Chest radiogra- tient s overall appearance and the clinical findings
phy revealed diffuse cardiac enlargement and left began to improve slowly. Blood pressure became
ventricular hypertrophy. Based upon the history better controlled, congestive failure showed im-
and clinical findings, what is your diagnosis and provement, insulin resistance diminished, and bone
what treatment do you recommend? density improved. Corticotrophin levels eventually
fell (from 18.5 to 8 ng/L) and serum cortisol became
ANSWER: This study describes the clinical features of
normally responsive to exogenous corticotrophin
Cushing s disease (pituitary-dependent hypercorti-
(rising from 407 to 1089 nM). After 6 months, the
solism), the tests for its diagnosis, and its treatment.
combination of metyrapone and aminoglutethimide
The combination of hypertension, congestive heart
was tapered and terminated, and radiation therapy
failure, and hyperglycemia (blood glucose 220
was initiated. This study illustrates the important
mg/dL) suggest hypercortisolism (Cushing s syn-
principle that clinical acumen and judicious use of
drome). This tentative diagnosis was supported by a
drugs in diagnosis and treatment can lead to the
low-dose (1 mg) dexamethasone overnight suppres-
dramatic reversal of the metabolic and cardiovascu-
sion test demonstrating unsuppressed serum corti-
lar abnormalities in a patient with severe Cushing s
sol (1409 nM). It was further substantiated by ele-
syndrome.
vated corticotrophin (85 pM) and suppression of
serum cortisol (598 nM) by high-dose (10 mg) dex-
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