Disorders Of The Adrenal Glands 25

Disorders of the adrenal glands Wu Yudong M.D. 武玉东 The First Teaching Hospital of Zhengzhou University

ADRENAL GLANDS Anatomy

ADRENAL GLANDS Anatomy

Disorders of the adrenal glands  Hyperaldosteronism

 Cushing

syndrome

Aldosterone

Glucocorticoids

Sex steroids  pheochromocytoma

Catecholamines

Cushing syndrome  Concept:

Cushing syndrome is the clinical disorder caused by overproduction of cortisol  Etiology: Cushing disease(80%) Ectopic production of ACTH(10%) Adrenal adenoma and carcinoma (10%)

CUSHING SYNDROME Symptoms and Signs  The

presence of at least 3 of the following strongly suggests Cushing syndrome:

 Obesity

(with sparing of the extremities), moon face, and fat pads of the supraclavicular and dorsocervical areas (buffalo hump)

CUSHING SYNDROME Symptoms and Signs  Striae

(red and depressed) over the abdomen and thighs.  Hypertension (almost always present).  Proximal myopathy with marked weakness

CUSHING SYNDROME Symptoms and Signs  Emotional

lability, irritability, difficulty in sleeping, and sometimes psychotic personality  Osteoporosis (common)  hyperglycemia

CUSHING SYNDROME Diagnosis  Symptoms

and Signs  Specific tests for Cushing syndrome 24-h urinary cortisol level Suppression of ACTH and plasma cortisol by dexamethasone(low doses)

CUSHING SYNDROME Diagnosis  Specific

tests for differentiation of causes of Cushing syndrome: Plasma ACTH level Suppression of ACTH and plasma cortisol by dexamethasone(large doses)

CUSHING SYNDROME Diagnosis  X-Ray

Findings and Special Examinations: 1.Localization of source of ACTH excess Pituitary MRI Anterior pituitary venous ACTH CT scans of the chest and abdomen

CUSHING SYNDROME Diagnosis 2. Localization of adrenal lesions: CT scan of the abdomen Adrenal tumor: >3cm, contralateral adrenal is suppressed and therefore appears atrophic or normal Adrenal adenoma:3-6cm Adrenal carcinoma:>5cm Cushing disease or the ectopic ACTH syndrome: bilateral adrenal enlargement

CUSHING SYNDROME Diagnosis

CUSHING SYNDROME Treatment  Cushing

Disease:localization and removing pituitary microadenoma  Ectopic ACTH Syndrome: Removal of the primary tumor Bilateral adrenalectomy

CUSHING SYNDROME Treatment  Total

Bilateral Adrenalectomy

 Adrenal

adenoma and adenocarcinoma

PRIMARY ALDOSTERONISM  Concept:

Excessive production of aldosterone leads to the combination of hypertension, hypokalemia, nocturia, and polyuria

 Etiology:

aldosteronoma spontaneous bilateral hyperplasia of the zona glomerulosa of the adrenal cortex

PRIMARY ALDOSTERONISM Pathophysiology Excessive aldosterone

Plasma renin plasma angiotensin

distal renal tubule

urinary potassium loss renal sodium reabsorption hydrogen ion secretion

potassium depletion metabolic alkalosis plasma sodium concentration hypervolemia

PRIMARY ALDOSTERONISM Symptoms and Signs  Hypertension  Hypokalemia:rare

episodes of paralysis  Nocturia and polyuria  Alkalosis:Numbness and tingling of the extremities, tetany

PRIMARY ALDOSTERONISM Diagnosis  Symptoms

and Signs  Elevated plasma aldosterone with suppressed plasma renin (20:1)  Elevated aldosterone level in 24-h urine  Localization: A thin-section CT scan Adrenal vein sampling of aldosterone and cortisol

PRIMARY ALDOSTERONISM Diagnosis

PRIMARY ALDOSTERONISM Treatment  Aldosteronoma:

laparoscopic unilateral adrenalectomy  Bilateral Nodular Hyperplasla: Medical treatment  Medical

Treatment:Spironolactone (Aldactone), 25-50 mg orally 4 times daily Other antihypertensive agents

PHEOCHROMOCYTOMA  Derived

from the neural crest  Disease of the adrenal medulla  Surgically curable hypertensive syndromes  Fewer than 1% of cases of hypertension  10% with extra-adrenal  10% with bilateral  10% with malignant

PHEOCHROMOCYTOMA Symptoms and Signs  Hypertension:

Headache, sweating accompanied by flushing or blanching, Tachycardia with palpitations, weakness, nausea and vomiting  Postural hypotension  psychic instability

PHEOCHROMOCYTOMA Diagnosis Biochemical diagnosis  Principles: 1.Screening the hypertensive population is not recommended because of the low incidence of pheochromocytoma (about 0.1%) 2. Methods using high-performance liquid chromatography, radioimmunoassay, or radioenzymatic assays should be selected 3. More than 80% of these patients have urine values 2 times greater than normal and total plasma catecholamine (Epi + Norepi) above 2000ng/L

PHEOCHROMOCYTOMA Diagnosis 4.Patients with only episodic hypertension may have normal random plasma catecholamine levels and normal 24-h urine values. Evaluation of these patients must be directed to obtaining plasma catecholamine during an episode or having the patient collect timed urine values (eg, 2-4 h) from the onset of an episode 5. Suppression or stimulation tests are not recommended except in the rare instances when the diagnosis cannot be established by routine procedures

PHEOCHROMOCYTOMA Biochemical Diagnosis  Urinary

catecholamines metanephrines catecholamine vanillylmandelic acid(VMA)  Plasma catecholamines

PHEOCHROMOCYTOMA Localization Diagnosis  CT  MRI  MIBG

PHEOCHROMOCYTOMA Localization Diagnosis

PHEOCHROMOCYTOMA Therapy  Preoperative

management: alpha-adrenergic blocker phenoxybenzamine (10mg twice daily~100-200mg/d) intravenous fluids

several weeks until the blood pressure is less than 160/90 mm Hg and symptoms are abolished

PHEOCHROMOCYTOMA Therapy Surgery  hypertension controlled with nitroprusside  Adequate volume replacement  solitary adrenal lesion:laparoscopic approach  Bilateral or malignant disease requires a transabdominal approach