Examkin

Question

Difficulty: HardBreast and Endocrine Surgery

A 4242-year-old female patient arrives at the outpatient clinic reporting a 1212-month history of unexplained weight gain, severe fatigue, and frequent bruising. Her blood pressure is 155/95 mm Hg155/95\text{ mm Hg}. Physical examination is notable for central adiposity, facial plethora, and wide, purplish striae on the lower abdomen. She denies taking any medications, including topical, inhaled, or intra-articular corticosteroids. The physician suspects an endogenous endocrine disorder. Arrange the following interventions in the most appropriate chronological sequence for the diagnosis and surgical management of this patient's condition.

  1. 1Perform a 1-mg1\text{-mg} overnight dexamethasone suppression test to confirm endogenous hypercortisolism.
  2. 2Measure early morning plasma adrenocorticotropic hormone (ACTH) concentration.
  3. 3Obtain a computed tomography (CT) scan of the abdomen for anatomic localization.
  4. 4Perform a unilateral laparoscopic adrenalectomy.
  5. 5Administer postoperative maintenance hydrocortisone therapy to prevent adrenal crisis.

Answer

The correct sequence for the diagnostic and surgical management of suspected Cushing syndrome is: 1) biochemical confirmation of hypercortisolism, 2) determination of ACTH dependence, 3) anatomic localization with imaging, 4) surgical resection, and 5) postoperative glucocorticoid replacement.
The evaluation of Cushing syndrome must follow a strict algorithmic approach to prevent diagnostic errors. First, endogenous hypercortisolism must be confirmed (e.g., via a 1-mg1\text{-mg} dexamethasone suppression test). Second, a plasma ACTH level is drawn to differentiate ACTH-independent (adrenal) from ACTH-dependent (pituitary/ectopic) disease. Third, only after an ACTH-independent source is confirmed should adrenal imaging (CT) be obtained to localize the tumor. Proceeding to a unilateral laparoscopic adrenalectomy removes the offending lesion. Finally, because the chronic cortisol excess suppresses the hypothalamic-pituitary-adrenal axis, the contralateral adrenal gland is atrophic. Therefore, postoperative hydrocortisone is mandatory to prevent an acute adrenal crisis.

Step-by-Step Solution

1
Confirm endogenous hypercortisolism.
The 1-mg1\text{-mg} overnight dexamethasone suppression test is performed.
Clinical suspicion must first be biochemically verified to ensure the patient's symptoms are due to true, autonomous cortisol excess rather than physiologic states.
2
Measure plasma ACTH concentration.
The ACTH level determines the dependency and source of cortisol production.
This differentiates an adrenal source (ACTH-independent, suppressed ACTH) from a pituitary or ectopic source (ACTH-dependent, normal or elevated ACTH).
3
Obtain abdominal imaging.
A CT scan of the adrenal glands is performed.
Once an ACTH-independent source is identified biochemically, cross-sectional imaging is used to localize the specific adrenal lesion for surgical planning.
4
Proceed with operative intervention.
Unilateral laparoscopic adrenalectomy is performed.
Resection of the hyperfunctioning adenoma is the definitive curative treatment for the condition.
5
Manage postoperative endocrine function.
Hydrocortisone therapy is initiated.
The contralateral adrenal gland is suppressed by long-standing hypercortisolism, creating a high risk for acute secondary adrenal insufficiency immediately after tumor removal.

Key Concept

The diagnostic workup and perioperative management sequence of ACTH-independent Cushing syndrome (adrenal adenoma).
Rate this question

Topics

Breast and Endocrine Surgery

More questions from this topic