ADRENAL GLAND DISORDERS Dr. Hany Ahmed Assistant Professor of Physiology (MD, PhD). Al Maarefa Colleges (KSA) & Zagazig University (ARE) Specialist of Diabetes, Metabolism and Obesity Zagazig Obesity Management & Research Unit

Lecture Objectives At the end of this lecture, the student should be able to: Describe pheochromocytoma Enumerate the disorders of adrenocortical function Describe the Pathophysiology of hypofunction of adrenal cortex Describe the Pathophysiology of hyperfunction of adrenal cortex

Tumor of suprarenal medulla (PHEOCHROMOCYTOMA) Excessive catecholamines secretion. Patient develops persistent or paroxysmal attacks of hypertension, hyperglycemia and  metabolic rate. The attacks are precipitated by emotion, exercise or meal. The attack consists of severe headache, sweating, pallor, pain in chest, vomiting and dilatation of pupil. Treated during attack by combined α-blocker & β-blocker. Then, surgical removal is done after attack.

DISORDERS OF ADRENOCORTICAL FUNCTION

Adrenocortical hormones Hypersecretion Aldosterone Conn’s syndrome 2ry Hyper Aldosteronism Cortisol Cushing’s DHEA Adrenogenital Syndrome Hyposecretion Addison’s Disease Pathophysiology

1- CHRONIC ADRENAL INSUFFICIENCY (=ADDISON’S DISEASE ) Chronic insufficiency of both cortisol and aldosterone Causes: Atrophy or destruction of gland by TB & Autoimmune adrenalitis. Clinical picture: Hyperpigmentation of skin: In exposed areas, points of friction and pressure, scar and areolae. Due to ↑ melanin pigment as a result of ↑ ACTH as a feedback mechanism (due to  cortisol). Hypotension & Postural Hypotension: due to volume depletion (Na+ & fluid depletion).

ADDISON’S DISEASE 3) Hyponatremia & hypotension. 4) Hyperkalaemia & Hypoglycemia  Muscular weakness. 5) Vomiting & dehydration. 6) Dehydration  hypotension   renal blood flow & GFR  Oliguria  urea retention. 7) ↓ Capacity to withstand stresses e.g. hemorrhage Treatment: Replacement therapy

ADDISON’S DISEASE Features related to Aldosterone deficiency Hyperkalemia Hyponatremia Disturbed cardiac rhythm Hypotension Features related to cortisol deficiency Poor response to stress Hypoglycemia Hyperpigmentation of the skin

2- ACUTE ADRENAL INSUFFICIENCY (= ADRENAL CRISIS) Causes: Exposure to a sudden stress (infection or operation) in patients with adrenals secreting basal amount of cortisol only. Direct damage of adrenal cortex by meningococcal septicemia.

ADRENAL CRISIS Clinical picture: Hyponatremia & hypotension. Hyperkalaemia & Hypoglycemia  Muscular weakness. Vomiting & dehydration. Oliguria  urea retention. Shock & death Treatment: IV fluids & cortisone.

HYPERALDOSTERONISM Primary hyperaldosteronism (Conn’s syndrome): Cause: Adrenal tumor of aldosterone – secreting cells Secondary hyperaldosteronism: Inappropriately high activity of renin-angiotensin-aldosterone system

CUSHING’S SYNDROME Prolonged excessive production of Cortisol due to: Causes: 1- Adrenal tumor (Cushing ,s syndrome)    Cortisol. 2- Pituitary adenoma (Cushing ,s disease)    ACTH  adrenal hyperplasia. Clinical picture: Wasting & weakness of skeletal muscles due to: Protein breakdown of muscle. 2) Abnormal distribution of fat: Face becomes rounded (= moon-face). Fat deposition in supraclavicular region and on back of neck (buffalo-neck). 3) Hyperglycemia & glucosuria (=Adrenal diabetes).

CUSHING’S SYNDROME Pendulous abdomen with Purplish striae (due to stretching of skin and tearing of weak subcutaneous tissues). Skin is thin with easy bruising, acne and excess body and facial hair. Osteoporosis due to loss of protein matrix & demineralization of bones. Polycythaemia &  lymphocytes and eosinophils. Retention of Na+ & fluids  oedema & hypertension. Hypokalaemia.

C CENTRAL OBESITY, CERVICAL FAT PADS, COLLAGEN FIBER WEAKNESS U URINARY FREE CORTISOL & GLUCOSE INCREASE S STRIAE & SUPPRESSED IMMUNITY H HYPERGLYCEMIA, HYPERTENSION & HIRSUTISM I INCREASED PLASMA CORTISOL & GLUCOSE LEVEL. N NEOPLASMS (ADRENAL OR PITUITARY TUMOUR) G GONADAL AFFECTION (AMENORRHEA) & GROWTH RETARDATION

ADRENOGENITAL SYNDROME Excessive production of sex hormones (mainly male sex hormones). Male Female Before Birth Enlarged external genitalia (Macro-genitosomia precox) Enlarged clitoris & labia resembling that of male external genitalia (♀ Pseudo-hermaphroditism) In Childhood Premature sexual development Enlarged penis. Appearance of pubic hair. Short (early union of epiphysis) (Precocious Pseudopuberty) i.e.Precocious development of 2ry Sex characters Without testicular growth. No development of ♀ sexual characters. No enlargement of breast Deepening of voice. Muscular growth. Adulthood -  Muscular power -  Sexual desire. Virilism Hirsutism = Male hair distribution. Frontal balding & Deepening of voice. Amenorrhea. Atrophy of uterus & breast. Clitoris Hypertrophy & Homosexuality.

Hormonal interrelationships in adrenogenital syndrome

Endocrine response to stress

References Human physiology, Lauralee Sherwood, seventh edition. Text book physiology by Guyton &Hall,11th edition. Text book of physiology by Linda .S .Costanzo third edition