Pituitary Adenomas

Treatment of Acromegaly/Gigantism

surgery

Treatment of Pheochromocytoma/Paragangliomas

surgical resection of tumor must treat HTN and tachyarrhythmias medically prior to surgery --HTN control -- start with alpha blockers -- phenoxybenzamine

Pheochromocytoma

tumor that arises from adrenal medulla secretes both epinephrine and norepinephrine

Diagnosis of Cushing's

*1. Dexamethasone suppression test* (screening test) --administer dexamethasone at 11pm and then serum collected for cortisol at 8am the next day --Dexamthasone is an exogenous steroid that provides negative feedback to the pituitary to suppress the secretion of ACTH --normal result = decrease in cortisol levels upon administration of low-dose dexamethasone -- Cushing's result = no change in cortisol on low-dose dexamethasone *2. 24-hour Urinary Free Cortisol level* --do if dexamathasone suppression test is abnormal --finding suggestive of Cushing's is >3-4 times than normal *3. CT adrenals* *4. MRI pituitary*

Clinical Findings of Prolactinoma in Women

*1. Galactorrhea* --lactation in the absence of nursing due to the direct physiologic effect of prolactin on breast epithelial cells *2. Reproductive dysfunction* --results from prolactin suppression of GnRH --experience: 1. Oligomenorrhea 2. Infertility 3. Amenorrhea (in non-pregnant women) *3. Visual Changes, headache*

Clinical Manifestations of Diabetes Insipidus

*1. Intense thirst* --increased ingestion of fluid 2L-20L per day *2. Polyuria* --most patients are able to maintain fluid balance by continuing to ingest large volumes of water --Hypernatremia and dehydration can occur in patients w/o access to water or a damaged hypothalamic thirst center/altered thirst sensation --Treatment = IV fluids

Treatment of Hyperprolactinemia

*1. Medical management* (make it smaller) --DOC: Bromocripitine mesylate ---dopamine agonist; normalization of visual fields in 90% of pts; failure to improve in 1-3 months = surgery --Tumors usually shrink 50% of their original size in approx. 90% of pts treated for macroadenomas for 1 yr. *2. Surgical Management* --Transsphenoidal removal of pituitary tumor

Prolactinoma

-prolactin-secreting pituitary adenoma -Prolactin's primary function is to enhance breast development during pregnancy and to induce lactation -most common and account for ~30% of all pituitary tumors

Hormones of the Adrenal gland

aldosterone cortisol

Categories of Pituitary Adenomas

*1. Non-secreting pituitary tumors* -- do not make extra hormones; just experience vision changes *2. Secretory pituitary tumors* --tumors secrete one or more hormones in excess; have the symptoms of excess hormones --usually found due to hormonal imbalances that affect bodily functions; may be relatively small --50% of adenomas are secretory

Clinical Findings of Prolactinoma in Men

*1. Sexual dysfunction* --erectile dysfunction, decreased libido --Suppression of GnRH leads to decreased LH which results in decreased testosterone and hypogonadism *2. Gynecomastia* without galactorrhea --enlargement of breast tissue in males *3. Visual field defects* *4. Headache*

Diagnosis of Diabetes Insipidus

no single diagnostic lab test obtain accurate 24 hr urine collection --Volume of <2L in 24 hrs R/O diabetes insipidus

Imaging of Pheochromocytoma/Paragangliomas

CT without contrast or MRI of abdomen

Impact of norepinephrine and epinephrine

Norepinephrine -- causes hypertension Epinephrine -- causes tachyarrhythmias

Clinical manifestations of Pheochromocytoma/Paragangliomas

can be lethal unless diagnosed and treated properly 1. catastrophic HTN crisis 2. potentially fatal cardiac arrhythmias 3. other symptoms -- mimic anxiety attack

Pituitary Adenomas

common and most often *benign* tumors of the pituitary gland can develop at any age most are located in the anterior lobe of the pituitary

Paragangliomas

extra-adrenal pheochromocytomas located along sympathetic nervous chain secretes norepinephrine

PE of hyperprolactinemia

galactorrhea in females gynecomastia in males visual-field defects in both

Gigantism

in youth increased release of GH happens before the closure of epiphyses super tall, long bones

Addison's Disease

occurs with destruction or dysfunction of adrenal cortices characterized by: 1. *Chronic deficiency* of cortisol and often aldosterone because adrenal cortices are dysfunctional ; also called adrenal insufficiency or hypocortisolism 2. *elevation of serum ACTH* because pituitary still working

Major PE findings of Addison's Disease

Skin changes -- areas of hyperpigmentation seen in hand creases, dental-gingival margins, buccal and vaginal mucosa, lips, aerola, pressure points (elbows/knees), scars and skin folds

Manifestations of Pituitary Adenomas

*1. Visual Defects* --lose peripheral vision bilaterally --*Bitemporal hemianopsia* -- arises from compression of the optic nerve by the tumor at the optic chiasm --often associated with ocular muscle palsy (trouble tracking on EOMs) and +/- a headache *2. Headache*-- due to the enlargement of the mass *3. Manifestations of Hypersecretion or Hyposecretion of hormones due to the adenoma* --Prolactin (hyper), GH (hyper or hypo), TSH (hyper), ADH (hypo from posterior pituitary)

Clinical Manifestations of Pheochromocytoma/Paragangliomas (CMDT chart)

*Blood pressure* -- HTN: severe or mild, paroxysmal or sustained; orthostasis; hypotension/shock; normotension *Cardiovascular* -- palpitations, dysrhythmias, chest pain, ACS, cardiomyopathy, heart failure, cardiac paragangliomas *Gastrointestinal* -- abdominal pain, N/V, weight loss, intestinal ischemia; pancreatitis, cholecystitis, jaundice; rupture of abdominal aneurysm; constipation, toxic megacolon

Lab Findings of Pheochromocytoma/Paragangliomas

*Plasma fractionate free metanephrines* -- single most sensitive test *24 hr urine specimen* -- metanephrines and catecholamines --important because: catecholamines secretion tends to fluctuate over time, a 24 hr urine test for metanephrines or catecholamines may detect excess production that is missed with a blood test

Adrenal Insufficiency (primary vs. secondary)

*Primary* - Addison's disease; patients have all symptoms including increased ACTH levels due to decreased feedback which causes characteristic skin coloration changes *Secondary* - due to pituitary gland disorder; lack of ACTH plus patient lacks characteristic skin coloration changes

Etiology of Addison's Disease

*autoimmune adrenal insufficiency = 80%* *TB -- most common worldwide* HIV Chronic fungal infection Rare M=F

Causes of Diabetes Insipidus

-Damage to hypothalamus or pituitary stalk by tumor -Encephalopathy -Surgical or accidental trauma -Infection -- encephalitis -Metastases to pituitary is more likely to be the cause than pituitary adenomas

Adrenal Hormone Pathway

-Hypothalamus sends *corticotropin releasing hormone* to the pituitary gland -CRH causes the anterior pituitary to secrete *ACTH* which stimulates the adrenal glands -When *adrenals* receive the ACTH, they respond by releasing *cortisol* into the bloodstream

Hypernatremia

-elevated sodium level in the blood -generally not caused by an excess of sodium but rather by a relative deficit of free water in the body -often synonymous with dehydration

Cortisol

-major glucocorticoid secreted by adrenal gland -counters insulin effects, tending to cause hyperglycemia by inhibiting insulin secretion and by increasing hepatic gluconeogenesis -secreted in diurnal pattern, being highest upon wakening and lowest at bedtime

Aldosterone

-major mineralocorticoid secreted by outer layer of the adrenal cortex -stimulates the renal tubule to reabsorb sodium and excrete potassium thereby protecting against hypovolemia and hyperkalemia

Cushing's Syndrome

-manifestation of excessive or high dose corticosteroids -commonly an unfortunate side effect when due to medications taken to treat illnesses such as: --Asthma --Rheumatoid arthritis --Systemic lupus --Inflammatory bowel disease --S/P transplant surgery prolonged exposure to elevated levels of corticosteroids

Cushing's Disease

-manifestation of hypercortisolism often due to ACTH hypersecretion by a benign adenoma in the pituitary (most common) -can also be caused by ACTH secreting tumors such as small cell lung cancer -Rare -most commonly affects adults aged 20-50 -Females more than males (5:1)

Autoimmune process of Addison's Disease

-most cases are caused by gradual destruction of the adrenal cortex by the body's own immune system -70% are caused by autoimmune disorders - immune system makes antibodies that attack the body's own tissues or organs and slowly destroys them -adrenal insufficiency occurs when at least 90% of the adrenal cortex has been destroyed

Acromegaly/Gigantism

-pituitary tumor causing increase in release of Growth Hormone from anterior pituitary -classification depends upon when it occurs --is the pt skeletally mature or immature? is there closure of growth plates? (x-ray of hand to find out)

Pheochromocytoma & Paraganglioma

-tumor of the sympathetic nervous system -engages fight or flight -symptoms are a collection of sympathetic nervous system hyperactivity -not very common

Diabetes Insipidus

-uncommon disease -increase thirst and passage of large quantities of urine of low specificity gravity (urine is clear, unconcentrated) -caused by deficiency of vasopressin (ADH) -lack of ADH results in large quantities of dilute urine being expelled

Diagnosis of Addison's Disease

1. decreased cortisol and aldosterone levels 2. ACTH challenge test -- measures the amount of cortisol and aldosterone in the blood and urine and then document a lack of the normal increase of these two hormones after administration of ACTH given by injection 3. An elevated blood level of ACTH 4. CT or MRI of adrenal glands

Functions of Cortisol

1. helps maintain blood pressure and cardiovascular function 2. helps slow the immune system's inflammatory response 3. helps balance the effects of insulin in breaking down sugar for energy 4. helps regulate the metabolism of proteins, carbohydrates and fats 5. helps maintain proper arousal and sense of well-being

Symptoms and Causes of Addison's Disease

Chronic fatigue -- decreased cortisol --> improper metabolism Hyperpigmentation of skin -- increased corticotropin levels due to decreased feedback

Treatment of Cushing's

Cushing's disease = Transsphenoidal resection of pituitary adenoma Cushing's syndrome = slowly wean of steroid

Manifestations of "acute onset of symptoms" of Pheochromocytoma/Paragangliomas

HTN severe headache cardiac palpitations anxiety tremor tachyarrhythmias

Treatment of Addison's Disease

Hydrocortisone -- DOC -- to replace cortisol Fludrocortisone acetate -- to replace aldosterone

Symptoms of Cushing's

Hypertension and Cardiovascular disease =#1 complication *1. Weight gain* --truncal obesity (face, neck, trunk, abdomen) --Buffalo hump, moon face *2. Skin changes* --thin, fragile, susceptible to bruises --wide, reddish-purple striae *3. Symptoms of androgen excess* --Hirsutism -- growth of coarse body hair in a male pattern (seen in females) *4. Glucose Intolerance* --excess cortisol can cause elevation of blood glucose levels *5. Psychologic symptoms* --loss of emotional control and depression to panic attacks and paranoia *6. Infections* --cortisol suppresses immune system = develop infections more frequently

Lab Findings of Acromegaly/Gigantism

IGF-1 -- increase over 5 times normal GH stimulates the release for Insulin-like Growth Factor-1 from liver thus an increase in GH produces an increase of IGF-1 which can be measured in the serum

Triggers of Pheochromocytoma/Paragangliomas

IV contrast dye Anesthesia Surgical Procedures Episodes can also be triggered by emotional stress, exercise, lifting, bending Drugs (caffeine, nicotine, amphetamines, etc.)

Imaging of Acromegaly/Gigantism

MRI -- shows pituitary tumor (90% are benign)

Diagnosis of Prolactinoma

MRI to evaluate for presence of tumor Serum evidence of hyperprolactinemia

Treatment of Diabetes Insipidus

Mild -- no treatment other than adequate fluid intake TOC: Desmopressin acetate (DDAVP) --synthetic replacement for vasopressin (ADH)

Labs of a Prolactinoma

Prolactin level increased

Patient's chief complaint of Pheochromocytoma/Paragangliomas

acute attacks of headache, perspiration, palpitations and anxiety ACS secondary to MI, TIA, CVA Aortic aneurysms may dissect or rupture

Acromegaly

after closure of epiphyses hands enlarge; doughy, moist handshake fingers widen; carpal tunnel syndrome Facial features --bones and sinsuses of skull enlarge --hat size increases --mandible becomes more prominent (malocclusion, tooth spacing widens) --Macroglossia -- hypertrophy of pharyngeal and laryngeal tissue; causes deep, hoarse voice