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ADRENAL DISORDERS. Dr. Atallah Al-Ruhaily Consultant Endocrinologist. Adrenal Insufficiency. Adrenocortical insufficiency (hypofunction of the adrenal cortex) includes all conditions in which there is deficient production of: Adrenal glucocorticoids Mineralocorticoids hormones.
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ADRENAL DISORDERS Dr. Atallah Al-Ruhaily Consultant Endocrinologist
AdrenalInsufficiency • Adrenocortical insufficiency (hypofunction of the adrenal cortex) includes all conditions in which there is deficient production of: • Adrenal glucocorticoids • Mineralocorticoids hormones.
Types of adrenal insufficiency • These conditions are divided into 2 general groups according to the level of hypofunction: • Primary adrenal insufficiency (Addison’s disease) • due to primary hypofunction of the adrenal cortex. • Secondary adrenal insufficiency • adrenocortical failure secondary to a primary deficient secretion of ACTH from the pituitary gland.
Etiology of Primary Adrenal Insufficiency • Anatomic destruction of gland (chronic & acute) • “Idiopathic” atrophy (autoimmune) • Surgical removal • Infection (Tb., fungal, viral-esp. AIDS) • Adrenal Hemorrhage • Invasion: metastases, amyloidosis, sarcoidosis • Metabolic failure in hormone production • Congenital adrenal hyperplasia (CAH) • Enzyme inhibitors: • (Metyrapone, Ketoconazole, Aminoglutethemide) • 3. Cytotoxic agents: (Mitotane) • ACTH-blocking Antibodies
Etiology of Secondary Adrenal Insufficiency • Hypopituitarism due to hypothalamic-pituitary disease. • Suppression of hypothalamic-pituitary axis. • Exogenous steroids (Iatrogenic) • Endogenous steroids (from tumors)
Incidence • Primary Adrenal Insufficiency: • Relatively rare. • Occurs at any age. • affects both sexes equally. • Secondary Adrenal Insufficiency: • Relatively common (because of common therapeutic use of steroids).
Addison’s Disease: Etiology and Pathogenesis Addison’s disease results from progressive destruction of adrenal cortex. At least 90% of gland is destroyed before signs of insufficiency appear.
Addison’s Disease: Etiology and Pathogenesis 50% of patients have +ve circulating adrenal Abs. Some Abs destroy the adrenal glands, others block the binding of ACTH to its receptors. In addition, some patients have +ve Abs to thyroid, parathyroid and/or gonadal tissues. Polyglandular Autoimmune (PGA) syndromes
Endocrine Disorders: Chronic lymphocytic thyroiditis Premature ovarian failure DM type 1 Primary hypothyroidism Hyperthyroidism NonendocrineDisorders: Pernicious anemia Vitiligo Alopecia Chronic active hepatitis Nontropicalsprue Myasthenia gravis Associated Autoimmune Disorders
Common Symptoms in chronic primary adrenal insufficiency
Common Signs in chronic primary adrenal insufficiency
Hyperpigmentation • Generalized hyperpigmentation of skin & mucous membrane (the classical physical finding). • Along with other features, suggests primary adrenocortical insufficiency. • One of earliest manifestations of Addison’s disease.
Hyperpigmentation • Increased at exposed areas and accentuated at pressure areas (knuckles, toes, elbows, knees) • Associated with black or dark brown freckles. • Hperpigmentation of buccal mucosa & gum is preceded by generalized hyperpigmentation of skin. • Other areas: palmar creases, nail beds, nipples, areolae, perivaginal, perianal mucosa & scars that formed after onset of ACTH excess (but not older scars).
Common Laboratory findings in chronic primary adrenal insufficiency
Adrenal Imaging Abdominal x-rays • Adrenal calcification in 50% tuberculous cases & some other invasive or hemorrhagic causes. CT Scan more sensitive for adrenal calcification & enlargement Causes of bilateral adrenal enlargement: • Tb • Fungal infection • CMV infection • Infiltrative diseases (malignant or nonmalignant) • Adrenal hemorrhage
Acute Adrenal Crisis • A state of acute adrenal insufficiency occurring in patients with Addison’s disease who are exposed to any form of stress. • Precipitating stress factors: • Infection • Trauma • Surgery • Dehydration (Salt deprivation, vomiting, diarrhea) • Discontinuation of steroids replacement therapy
Acute Adrenal Crisis: Clinical Features Common Clinical Features • Hypotension & shock • Fever (due to infection or hypoadrenalism per se) • Dehydration, volume depletion • Nausea, vomiting, anorexia • Abdominal pain (may mimic acute abdomen) • Weakness, apathy, depressed mentation • Hypoglycemia (more in children) • Shock and coma may rapidly lead to death in untreated patients.
Acute Adrenal Crisis Laboratory Findings Suggestive of Diagnosis • Hyponatremia & Hyperkalemia • (In a small number of acute cases). • Azotemia (usual) • Lymphocytosis • Eosinophilia • Hypoglycemia
Acute Adrenal Hemorrhage A progressively deteriorating condition resulting from bilateral adrenal hemorrhage and acute adrenal destruction in an already compromised patient with major illness.
Acute Adrenal HemorrhageManifestations • Abdominal, flank or back pain & abdominal tenderness (Less frequently, abdominal distention, rigidity & rebound tenderness). • Hypotension & shock • Fever • Nausea & Vomiting • Confusion & disorientation • Tachycardia
Acute Adrenal Hemorrhage With progression, the following manifestations may ensue: • Severe hypotension • Volume depletion • Dehydration • Hyperpyrexia • Cyanosis • Hypoglycemia • Coma • Death
Secondary Adrenal InsufficiencyCauses • ACTH deficiency most commonly due to exogenous glucocorticoid therapy. • Pituitary & Hypothalamus tumors the most common causes of naturally occurring pituitary ACTH hyposecretion.
Secondary Adrenal InsufficiencyPathophysiology • ACTH deficiency is the primary event. • This leads to: • Decreased Cortisol & Androgen secretion. • But Aldosterone secretion remains normal except in few cases.
Secondary Adrenal InsufficiencyPathophysiology • In early stages, • Basal ACTH & cortisol levels may be normal. • ACTH reserve is impaired. Response of ACTH & cortisol to stress is subnormal. • With further loss of basal ACTH secretion, • There is atrophy of Z. Fasciculata & Z. Reticularis. • Basal cortisol secretion is decreased. • The entire pituitary adrenal axis is impaired (i.e. Decreased ACTH responsiveness to stress & decreased adrenal responsiveness to stimulation with exogenous ACTH).
Secondary Adrenal InsufficiencyClinical Features • Usually chronic nonspecific manifestations. • Acute crisis occurs in: • Undiagnosed patients • Patients who do not receive increased steroid dosage during periods of stress.
Secondary Adrenal InsufficiencyClinical Features Clinical features differ from primary in that: • Hyperpigmentation does not occur (Because of ACTH deficiency). • Manifestations of mineralocorticoid deficiency are usually absent (Because Aldosterone secretion by Z. G. is usually preserved). Therefore: • Volume depletion, dehydration & hyperkalemia usually absent. • Hypotention is usually absent except in acute presentations. • Hyponatremia may occur as a result of water retention.
Secondary Adrenal InsufficiencyClinical Features Prominent features (due to glucocorticoid deficiency) are nonspecific & include: • Weakness, lethargy & easy fatigability • anorexia, nausea & occasionally vomiting • Arthralgias & myalgias • Hypoglycemia • Acute decompensation with severe hypotension or shock unresponsive to vasopressors.
Secondary Adrenal InsufficiencyAssociated Features • The following additional features may be present: • History of glucocorticoid therapy or Cushingoid features. • Features of loss of other pituitary hormones (hypogonadism & hypothyroidism). • Features of hypersecretion of GH or PRL from pituitary adenoma. • Pressure symptoms from pituitary tumors.
Overnight single-dose Metyrapone Test - Procedure Metayrapone : 30 mg/kg oral administration of Metyrapone at midnight with milk or snack. Serum 11-Deoxycortisol & Cortisol measurement (and ACTH level) 7:30 -9:30 AM next morning.
Overnight single-dose Metyrapone Test - Interpretation A normal response to the overnight single-dose test consists of: An 8 AM serum 11-deoxycortisol concentration of 7 to 22 mcg/dL (200 to 660 nmol/L). A serum cortisol concentration at 8 AM of less than 5 mcg/dL (138 nmol/L) confirms adequate.
Diagnosis of Adrenal Insufficiency 3 Stages of diagnosis confirmation: • Inappropriately low cortisol secretion? • .. • Is cortisol deficiency dependent on or independent of corticotropin (ACTH) deficiency • Evaluating mineralocorticoid secretion in patients without ACTH deficiency. • Is there a treatable cause of the primary disorder?
Diagnosis of Adrenal Insufficiency • Measuring non-specific anti-adrenal antibodies in serum by indirect immunofluorescence is not useful for establishing the diagnosis. • Antibodies directed to 21-hydroxylase (P450c21) identify nearly all patients with autoimmune adrenal insufficiency and is not positive in any patient with adrenoleukodystrophy-associated adrenal insufficiency.
Diagnosis of Adrenal Insufficiency • Basal levels of adrenocortical steroids in plasma or urine may be normal in partial adrenal insufficiency. • Tests for adrenocortical reserve are necessary to establish the diagnosis. • Rapid ACTH Stimulation Test • Plasma ACTH Levels • Metyrapone Test • Insulin-induced Hypoglycemia • CRH Stimulation
Diagnosis of Adrenal Insufficiency • Other indirect clues: • Features of hypersecretion of GH or PRL from pituitary adenoma. • Pressure symptoms from pituitary tumors.
Evaluation of Suspected Adrenal Insufficiency Rapid ACTH Stimulation Test • Abormal ACTH Stimulation Test: Adrenocortical insufficiency +ve. Which type? • Plasma ACTH level: • Elevated: Primary Adrenal Insufficiency +ve • Normal or Low: Secondary Adrenal Insufficiency +ve
Evaluation of Suspected Adrenal Insufficiency Rapid ACTH Stimulation Test • Normal ACTH Stimulation Test: • This excludes Primary Adrenal Insufficiency & Adrenal atrophy. • But does not exclude “Decreased ACTH Reserve” • Metyrapone Test • or Insulin-hypoglycemia Test • or CRH stimulation Test: • Normal: Exclude Adrenal Insufficiency • Abnormal: Secondary Adrenal Insufficiency +ve
Treatment of Adrenal InsufficiencyAcute Addisonian Crisis • Glucocorticoid Replacement • Cortisol (Hyrdocortisone succinate or phosphate) 100 mg every 6 hrs. for 24 hrs. • When stable, reduce to 50 mg 6 hrs. • Taper to maintenance therapy by day 4 or 5 & add mineralocorticoid as required. • If complications persist or occur, maintain or increase the dose to 200-400 mg/d. • General or Supportive Measures • Correct volume depletion, dehydration, & hypoglycemia with I.V. saline and glucose. • Evaluate and treat infection or other precipitating factors.
Treatment of Adrenal InsufficiencyMaintenance Therapy • Life-long replacement therapy with glucocorticoid and mineralocorticoid. • Preparations: • Cortisol (hydrocortisone) tablets • First choice • Maintenance dose: 15-30 mg/d. • Usually, divided into 2 doses (2/3 AM & 1/3 PM) • Cortisone acetate (37.5mg/d) • Absorbed rapidly from GIT • converted in the liver to cortisol.
Treatment of Adrenal InsufficiencyMaintenance Therapy Synthetic Steroids: - Prednisone or Prednisolone 5 mg of prednisone tab is equivalent to 20 mg of hydrocortisone. - Fludrocortisone (9-alpha fludrocortisol) • Used for mineralocorticoid therapy • Usual dose: 0.05-0.1 mg/d PO AM
Treatment of Primary Adrenal InsufficiencyRegimen Therapy • Cortisol 15-20 mg AM & 10 mg at 4-5 pm • Or prednisone 5.0-7.5 mg AM • Fludrocortisone (Fluranif) 0.05 0.1 mg PO AM. • Clinical Follow up: • Maintenance of normal body weight, BP & electrolytes • Regression of clinical features • Patient education & identification card or bracelet • Increased cortisol dosage during stress.