Patho: Endocrine Disorders I Lecture 14

Typically, due to hyposecretion of hormone May also be due to decline in target tissue responsiveness to hormone

• Typically, due to hypersecretion of hormone
• May also be due to hormone production by ectopic tumor

• are chemical messengers that travel through the bloodstream to exert physiologic effects on specific target cells and tissues.
• In the healthy state, hormones are released by endocrine glands when their action is needed and inhibited when their effect is attained.

• Primary Defects – Endocrine gland
• Secondary Defects – Pituitary Gland
• Tertiary Defects - Hypothalamus

• endocrine gland
• result from intrinsic defects within the hormone-secreting gland

• pituitary gland
• manufactures and stimulate hypothalamus stimulating hormone
• abnormal secretion

• hypothalamus
• the controller

• increased metabolim and protein synthesis
• neccesary for growth and development in children esp for normal growth of CNS

• pituitary tumors
• hypopituitarism
• isosexual precocious puberty

• May be primary tumors or secondary (metastatic tumors)
• May be functional tumors or nonfunctional tumors
• Benign adenomas account for most of functional tumors

Hormones become deficient in order: GH, FSH & LH, TSH, ACTH

• Short Stature and Growth Hormone Deficiency in Children - Dwarfism
• Growth Hormone Deficiency in Adults – Increased CV mortality
• Tall Stature and Growth Hormone Excess in Children - Gigantism
• Growth Hormone Excess in Adults - Acromegaly

Often caused by tumors (gonadal, adrenal, hypothalamic, CNS)

• Tumors and mass lesions
• Pituitary surgery or radiation
• infiltrative lesions and infections
• pituitary infarctions

• cause of hypopituitarism
• pituitary adenomas, cysts, metastatic cancer, and other legions

• cause of hypopituitarism
• hemochromatosis, lymphocytic hypophysitis

• cause of hypopituitarism
• infarction of the pituitary gland after substantial blood loss during child birth (Sheehan's syndrome)

• produce by somotropes in the anterior pituitary
• neccesary for linear bone growth in children
• stimulate cells to to increase in size and divide more rapidly
• enhances amino acid transport across cell membranes and increase protein synthesis
• increases the rate at which cells use fatty acids and decreases the rate at which they use carbs

require insulin like growth factors (somatomedins) which is produced by the liver

• interferes with linear bone growth resulting in short stature or dwarfism
• normal intelligence
• budgy, boarder line obesity
• delay in puberty
• typically have microphalis (boys) - small penis

• GH deficiency in children
• GH levels are normal or elevated but there is a hereditary defect in insulin like growth factors

• excess of growth hormone prior to puberty
• increased linear bone growth or gigantism
• caused by pituitary adenoma

• results in overgrowth of the cartiligenousparts of the skeleton
• enlargement of the heart and other organs of the body
• metabolic disturbances resulting in altered fat metabolism and impaired glucose tolerance
• effect small bones of the hands, mandible, feet, bones of the skull, etc

• hyperostosis -thoracic vertebrae
• increased size in hand and feet
• cardiomegaly
• abnormal glucose tolerence secondary to insulin resistance
• peripheral neuropathy
• degenerative arthritis

• due to pituitary adenoma that happens later in life
• increase size in nasal bone, skull bones
• increased prominance of chin
• enlargement of organs (cardiomegaly)

• Anterior pituitary, which is below the hypothylamus, secretes the growth hormone
• results in growth promoting actions or anti insulin effects

• actions of growth hormone
• increasedprotein synthesis results in
• 1. increased linear growth
• 2. increased size and function
• 3. increased lean muscle mass

• actions of growth hormone
• 1 Adipose tissue - increase lipolysis, increase FFA use, which decrease in adiposity
• 2. carb metabolism - decrease glucose use, which increase blood glucose

• variants of normal
• low birth weight
• endocrine disorders
• chronic illness and malnutrition
• functional endocrine disorders
• chromosomal disorders
• skeletal abnormalities

• absent or underdeveloped thyroid
• produces decrease in metabolic rate
• an accumulation of a hydrophilic mucopolysaccharide substance (myxedema) in the connective tissue throughout the body
• an elevation in serum cholesterol

• congenital hypothyroidism
• acquired hypothyroidism and myxedema

• Common cause of preventable mental retardation
• can cause cretadin if not treated within 6 weeks

Hashimoto Thyroiditis (autoimmune origin) Myxedematous Coma

• autoimmune origin
• most common acquired hypothyroidism
• antibodies manufactured and destroy the thyroid

• excessive nonpidding edema that patients with long-term hypothyroidism
• tend to demonstrate effects brain swelling functioning
• often seen in older women

enlarged thyroid

• also called thyrotoxicosis
• overactivity of the thyroid

• graves disease ( autoimmune origin)
• thyroid storm

• antibodies mimic thyroid stimulating hormone which results in the thyroid secreting more hormone
• causes goiter

• life-threatening
• happens when there is already hyperthyroidism that is not diagnoses
• percipitated by infection or diabetic ketoacidosis
• can be triggered by physical or emotional trauma

• decreased BMR
• decreased sensitivity to catecholamines
• general features: myxedematous features, deep voice, impaired growth (child)
• increased blood cholesterol levels
• decreased cardiac output and bradycardia
• gain weight

• increased BMR
• increased sensitivity to catecholamines
• general features: exophthalmos (in Graves Disease), lid lag, decreased blinking
• decreased blood cholesterol levels
• increased cardiac output and tachycardia an palpitations
• loss weight

• generalized edema; periphera edema
• slowing hert
• slowing metabolic rate, slow down peristalsis
• edema in vocal cords (deep course voice)
• constipation

• exophthalmos - bulging eys due to lids moved back on eye
• goiter
• tachycardia
• high output failure (oxygen used up at such increase causing increased heart rate)
• muscle wasting

• sits on top of the kidneys
• hormones generated from the cortext of the adrenal gland

stimulates adrenal cortex to produce cortisol

adrenal sex hormones

• congenital adrenal hyperplasia
• adrenal cortical insufficiency
• glucocorticoid hormone excess
• incidental adrenal mass

• Also known as Adrenogenital Syndrome
• Caused by an enzyme defect in the synthesis of cortisol, leading to excessive synthesis of adrenal androgens
• Most common enzyme deficiencies are 21-hydroxylase deficiency and 11-β-hydroxylase deficiency
• causes ambiguous genitalia - infusion of enlarged clitoris and infused labia

• Primanry
• Secondary
• Acute adrenal crisis

• also called addison disease
• chronic metabolic disorder
• needs lifetime treatment
• Autoimmune destruction of adrenal cortex is most common cause
• Characterized by hyponatremia, loss of extracellular fluid, decreased cardiac output, hyperkalemia, and orthostatic hypotension
• Dehydration, weakness and fatigue are common early symptoms

due to hypopituitarism

A life-threatening situation, requiring emergency medical treatment

• Hypercortisolism; also known as Cushing Syndrome
• Major manifestations of Cushing syndrome represent an exaggeration of the many actions of cortisol
• Derangements of glucose metabolism occur in 75% of persons with Cushing Syndrome; clinically overt diabetes mellitus occurs in about 20% of cases

• Pituitary form, due to excess ACTH production by a pituitary tumor
• Adrenal form, caused by benign or malignant adrenal tumor
• Ectopic form, due to ACTH-secreting tumor (e.g., lung cancer)

Primary adrenal carcinoma is rare, but the adrenal gland is a common site of metastasis, particularly of lung cancers (and other cancers)