disorders of the adrenocortical hormones dr. ayisha qureshi mbbs, mphil

DISORDERS OF THE ADRENOCORTICAL

HORMONES

Dr. Ayisha QureshiMBBS, Mphil

Hypoadrenalism- ADDISON’S DISEASE

ADDISON’S DISEASE

DEFINITION:Addison’s disease results from the inability of the

adrenal cortices to produce the adrenal hormones & this is most frequently caused by the primary atrophy

of adrenal cortex. CAUSES:1.Autoimmune disorder2.Tuberculous destruction of the glands3.Cancer4.Secondary to impaired pituitary gland function leading to insufficient ACTH production.

Signs & Symptoms

Mineralocorticoid deficiency• Greatly decreased renal

sodium reabsorption• Increased loss of Na, Cl &

water in the urine• Decreased ECF/ hypovolemia• Hyponatremia• Hyperkalemia• Mild Acidosis• Increased RBC conc. Due to

decreased ECF• Decreased CO• Shock • Death

Glucocorticoid deficiency• Patient cannot maintain

normal blood glucose levels as no gluconeogenesis b/w meals

• Nausea, vomiting, fever, hypotension

• All metabolisms effected• Patient highly susceptible to

the deteriorating effects of stress.

• Even mild infections can lead to death

Signs & Symptoms• Extreme melanin pigmentation of the mucous membranes &

skin.• Usually deposited in blotches• Cause is increased ACTH secretion as well as increased

MSH secretion WHAT IS POMC & MSH? Proopiomelanocortin (POMC) is a preprohormone which when

cleaved causes the formation of:• MSH (melanocyte stimulating hormone) which causes

darkening of the skin by stimulating formation of melanin & dispersing it to the epidermis

• Beta Lipoprotein• Beta endorphin & few others

(ACTH also has 1/30 as much activity of MSH & so its hypersecretion also causes Hyperpigmentation of the skin.)

TREATMENT

• A person with complete destruction of the adrenal may die within a few days to 2 weeks b/c of weakness & circulatory shock.

• However, if small quantities of mineralo & glucocorticoids are administered daily, they can live for years.

Hyperadrenalism- Cushing’s Syndrome

DEFINITION:Hypersecretion by the adrenal cortex causes a complex cascade

of hormone effects called Cushing’s syndrome. CAUSES: •Exogenous

- Factitious- Iatrogenic

•ACTH-Dependant- Pituitary adenoma- Ectopic ACTH syndrome

•ACTH-Independant- Adrenal adenoma- Adrenal carcinoma

When Cushing’s syndrome is secondary to excess secretion of ACTH by the anterior

pituitary, it is called CUSHING’S DISEASE.

Signs & Symptoms

• Truncal Obesity• Supraclavicular & dorsal

fat pad• Buffalo hump• Moon Facies• Purple striae due to

decreased collagen proteins

• Thin skin• Capillary fragility & easy

bruising• Hirsuitism

• Diabetes Mellitus also called Adrenal Diabetes

• Thin extremities and severe muscle weakness due to increased protein catabolism

• Infections due to suppressed immune system with impaired wound healing

• Osteoporosis • Hypertension

Diagnosis & Treatment

DIAGNOSIS:•Very challenging•Diagnose excess Cortisol (24 hour urine cortisol & midnight salivary cortisol level) •Dexamethasone suppression testTREATMENT:•Removal of the cause: Surgery of the adrenal tumour OR pituitary tumour•Drugs that block steroidogenesis.e.g. Ketaconazole•Drugs that inhibit ACTH secretion.e.g. Serotonin antagonists•Partial or total adrenalectomy

PRIMARY ALDOSTERONISM(CONN’S SYNDROME)

DEFINITION:Occasionally, a small tumor of the zona glomerulosa

cells occurs & secretes large amounts of aldosterone; the resulting condition is called

“Primary aldosteronism” or “ Conn’s disease”.CAUSES: •Small tumour of Zona Glomerulosa cells that secretes large amounts of Aldosterone.•Sometimes even hyperplastic adrenal cortices secrete aldosterone instead of cortisol.

Signs & Symptoms

• Severe hypokalemia causing muscle paralysis

• Increased blood and ECF volume

• Slight increase in Na conc.

• Hypertension

Usually, diagnosed by decreased plasma renin and increased aldosterone concentration.

ADRENOGENITAL SYNDROME

A syndrome that is caused by occasional adrenocortical tumour that secretes excessive quantities of androgens.

Signs & Symptoms

• In Females:

- Virile characteristics

- Growth of a beard

- Deeper voice

- Occasionally baldness

- Masculine distribution of hair on the body

- Deposition of proteins in a masculine manner

• In Males:- In prepubertal male, a virilizing adrenal

tumour causes same characteristics as in the female plus rapid development of the male sex organs

- In adult male, the virilising characteristics are often masked by the virilising effects of Testosterone

- Diagnosis is made by the presence of excess 17-ketosteroids in the urine.