Exam 3

• hyperfunction: glands produce too much of a hormone
• hypofunction: glands produce too little of a hormone
• tumors: neoplasia- either functioning or nonfunctioning

• synthesis or release is affected: deficiency
• there is abnormal target tissue: resistance
• there is an abnormal target response: resistance

• functioning: the tumor is producing a particular hormone
• nonfunctioning: the tumor is not producing a hormone

• autoimmune: Hashimotos, type 1 diabetes
• Post-surgical: removal or thyroid gland causing hypothyroidism/hypoparathyroidism
• Neoplasia: tumor production of hormone 
• Inflammation: destruction of endocrine glands from inflammatory cells
• Receptor defect/resistance: type II diabetes mellitus. cells have insulin resistance

a result of a functioning tumor in the cells of the pituitary gland in the skull

• visual field defects
• increased ICP due to incereased pituitary size
• Sxs related to overproduction of certain hormones

the pituitary gland is in the sella turcica- this is where the optic chiasma also is so the increased size of the pituiary pushes on it and causes visual problems

• growth hormone
• prolactin
• ACTH (adrenocorticotrophic hormone)

• functioning tumors are often caught earlier because there are early signs- the overproduction of hormones
• nonfunctional tumors have late sx because no hormone secreted. 
• sx only show up in a nonfunctional when its size is pushing on and affecting something else.

• between your 40s and 60s. 
• these tumors account for 10% of cranial tumors

• this is the effect from growth in tumor size
• in pituitary mass effect causes visual field changes and increased cranial pressure, headache, nausea and vomiting.

• headache
• vomiting
• visual impairment
• and altered consciousness with hemodynamic instability
• can happen in patients who have a pituitary tumor which leads to bleeding in the pit gland and ends up as pit hypofunction

• due to death of the cells in the gland from...
• ischemic injury
• radiation
• inflammation process that has affected the pituitary gland and therefore its hormone production

• depend on which hormone is decreased
• can happen due to a variation, inflammation, infection or some kind of compression of the gland like a tumor

• lutenizing hormone and follicule stimulating hormone
• in men: testosterone levels drop leading to decreased sexual drive and impotence
• in women: infertility

• infundibulum (the tube like strucutre that connects the posterior pituitary to the hypothalamus) can get inflamed or compressed by something like a tumor, giving us the stalk effect. 
• usualy leads to slight elevation in prolactin levels, much less than in prolactin producing tumors but still enough to cause women to get galactorrea and loose periods

• can affect thyroid gland and cause hypothyroidism 
• or affect adrenal gland and cause low cortisol levels which can be LIFE THREATENING

• they are general so a diagnosis has to be done by looking at hormonal effects
• weight loss or gain
• fatigue, decreased energy
• dizziness
• headaches
• pituitary apoplexy

• gigantism
• acromegaly

• galactorrhea (milk production)
• amenorrhea

• cushings disease
• nelsons syndrome (post adrenalectomy- if a patient has both adrenal glands removed which is rare)

• the most common pituitary adenoma
• hyperprolactinemia (prolactin is greater than 200ug/L)
• clinical status determines detection

• mircoadenomas: smaller nodules in female
• macroadenomas: larger nodules in males

• increased prolactin levels leading to 
• amenorrhea
• galactorrhea
• libdo loss
• infertility

• if it happens before epiphseal closure (replacement of the epiphyseal plate with the epiphyseal line which happens after puberty)prepubertal: gigantisism
• if it occurs after epiphyseal closure (in adults): acromegaly

• large body stature, increased height, delayed puberty
• long legs/arms
• longer bones
• enlarged hands, feet, tongue, nose, lips
• enlarged forehead and jaw, spreading of teeth
• artrhitis- bc of weight their joints dont work

• high blood pressure
• Diabetes mellitus
• heart disease 
• thyroid cancer
• colon polyps
• arthritis
• osteoporosis
• CHF

• died at 22 due to infection
• 8ft 4in
• had gigantism

• abnormal growth
• frontal bossing- protruding forehead
• prognathism (bulging of lower jaw)
• enlarged hands/feet/nose/tongue
• problems with perspiration
• galactorrhea
• enlarged colon, hepatomegaly, nephromegaly
• many other abnormalities due to GH late in life

• carpal tunnel
• diabetes mellitus
• hypertension
• arthritis
• osteoporosis
• CHF
• they also have a complicated histor after having extra doses of growth hormone after puberty

• hypothalamus secreates corticotrophin releasing hormone which stimulates the anterior pituitary to secrete ACTH which stimulates the adrenal coretex to make cortisol
• when cortisol high this inhibits the hyp from making CRH

• corticotrophin cell adomas
• corticotrophin cells in the anterior pituitary are responsible for producing ACTH
• A lot of ACTH is produced here due to the tumor 
• ACTH acts on the adrenal cortex and stimulates production of cortisol so you get high cortisol levels which causes Cushings disease (pituitary dependent increase in cortisol)
• the tumor is unresponsive to the bodys negative feedback to stop cortisol production (normally the hypothalamus would stop making corticotrophin releasing hormone and stop it but even when this happens the tumor still makes ACTH)
• High ACTH, high cortisol

• weight gain
• increased BP
• truncal obesity
• decreased muscle mass
• diabetes mellitus

women

• antidiuretic hormone (ADH) aka vasopressin
• oxytocin

• antidiuretic hormone/vasopressin
• increased absorption of water from the kidney resulting in...
• decreased urinary volume
• increased sodium conc. in urine
• increased serum volume
• decreased serum sodium conc.
• increased blood pressure due to increased volume

ADH IS RESPONSIBLE FOR RETENTION OF WATER ONLY, it does not stimulate sodium retention, the sodium effects are a secondary effect to water retention.

• stimulates contraction of uterus
• stimulated lactiferous ducts during pregnancy

• also called diabetes insipidous
• diabetes not related to hyperglycemia

• polyuria
• polydipsia
• dehydration
• no hyperglycemia

• large volumes of dilute urine
• decreased specificy gravity
• decreased urinary sodium concentration due to increased water
• increased serum sodium concentration
• increased serum osmolarity- because increased sodium concentration and water follows

• no pituitary gland
• lesions of posterior pituitary
• Rathke's cleft cyst (a pouch between ant. and pos. pituitary)
• infection- ie tuberculosis of the pit
• tumors- pushes on post pit and leads to cell death.

• Syndrome of inappropriate antidiuretic hormone
• usually bc of an ADH producing small cell (oat cell) carcinoma of the lung
• can also happen bc of CNS tumors or trauma

ADH produced by a tumor leading to increased water reabsorption from the renal tubules which causes increased blood volume, decreased urine ouput, increased urine sodium [], decreased serum sodium [ and decreased sodium osmolarity in serum bc its too dilute

• ADH excess
• concentrated urine
• dilute serum
• hyperosmolarity of urine- bc high sodium there
• hypoosmolarity of serum- bc low sodium there

• increased body water but no edema
• overhydration in general but the danger is in overhydration of the brain cells
• confusion if sodium drops below 125mM
• convulsions if sodium drops below 115mM
• coma/death

• Remove the cause (tumor, medication)
• resolve the trauma- the SIADH should resolve once the trauma heals
• restrict fluids
• give ADH antagonist- diuretics

• anterior and inferior to the larynx 
• has a left and right lobe connected by the isthmus
• contains most of the body's iodine

• adults and adolescents: 150ug
• pregnant women: 220ug
• Lactating women: 290ug
• children 1-11 years: 90-120ug
• infants: 110-130ug

• food and salt
• avg adult needs 100-150 ug/day to make thyroxin (aka T4)

• spherical follicles lined by cuboidal epithelium- this is what synthesizes the hormone tetraiodothyronine (T4)
• There is a protein called thyroglobulin in the colloid that stores T4 in the gland
• there are also 4 groups of cells called the parafollicular C cells (aka clear cells) that secrete calcitonin

• regulated by the anterior pituitary gland through the secretion of thyroid stimulating hormone (TSH)
• TSH stimulates the thyrooid gland to produce T4 
• When T4 level goes up, that negatively affects the hypothalamus and ant. pit. gland and stops the hyp from producsing thyroid releasing hormone and therefore when this stops the ant. pit. is no longer stimulated to produce TSH
• hypothalamus, ant. pit and thyroid all participate in a connected negative feedback loop

you produce T4 that eventually becomes T3 at the level of the tissue and then enters the cell and induces protein synthesis to increase the basal metabolic rate

• they increase the BMR and therefore the temperature
• when high thyroid hormone and BMR there is increased heart rate and CO
• increased gi motility
• increased bone turnover
• increased muscle contraction
• increased RBCs and 2,3DPG
• Increased gluconeogenesis
• increased cholesterol
• increased stimulation of symp NS
• increased b-adrenergic activity
• increased catecholemines

increased levels of T3 and T4

• diffuse hyperplasia (graves disease)
• taking too much exogenous thyroid hormone
• multinodular goiter
• adenoma of the thyroid
• post partum (not common)

thyrotoxicosis is usually graves disease, but these other things can cause it too

• nervousness
• tremor
• tachycardia
• palpitations
• hyperreflexia
• hypermotility of GI tract
• malabsorption
• diarrhea
• weight loss
• gaze
• warm flush skin

• an autoimmune disorder where you produce antibodies agaist TSH receptor which increases T3 and T4 activity and eventually affects the eyes
• most common cause of primary hyperthyroidism
• primarily occurs in women 30s-40s
• familial: HLA-DR3
• increased T3 and T4, Decreased TSH

• infiltrative opthalmopathy (eye bulging) and infiltrative dermatopathy
• these happen in graves disease

• low T3 and T4
• structural or functional interference with inadequate thyroid levels

• infancy/childhood hypothyroidism: cretinism- growth is retarded (body and brain function)
• Adult hypothyroidism: Myxedema

• goiter (can be caused by iodine deficiency)
• iodine deficiency
• hashimotos thyroiditis
• thyroid ablation
• infection of thyroid gland that leads to its destruction
• inflitration of thyroid gland by something like iodine leading to its destruction
• idiopathic primary

• pituitary disease
• hypothalamic disease

bc both pit and hyp regulate thyroid gland

• central: hypothalamic/piutitary 
• thyroidal: thyroid problem itself
• extrathyroidal: somehow there have been mutations taht lead to resistance to thyroid hormone by cells

• dwarfism
• enlarged tongue
• protuberent abdomen
• delayed epiphyseial union and dentation
• irreversable mental retardation if not corrected early

• myxedema
• weight gain
• muscle cramps
• fatigue
• slowed mentation
• slowed speech
• cold intolerance
• constipation
• cardiomegaly
• pericardial effusion

accumulation of mucopolysaccharide in and under skin and visceral sites resulting in non-pitting edema

• chronic thyroiditis
• radioactive I2 ablation
• suregical removal of thyroid
• I2 deficiency
• drugs (ie lithium)

• impaired (decreased) thyroid hormone- T3 or T4
• enlargement of the thyroid due to TSH stimulation
• the most common thyroid disease worldwide

iodine or t3 or t4 deficiency which leads to increased TSH to stimulate its production and when this continues to stimulate the thyroid becomes larger (hypertrophy and hyperplasia)

• endemic: iodine deficiency in mountainous regions. used to get in US but now Iodine in salt. still a big problem in developing world
• sporadic: usually unknown or from eating too many cruciferous vegetables

• graves: causes hyperthyroidism from anti TSH antibodies
• hashimotos: anti TSH RECEPTOR antibodies are made- the receptor on the thyroid gland is occupied by the antibodies so the TSH cant bind and the gland cant become stimulated so no t3/t4

• hypo: high TSH, low t3/t4. fatigue, weight gain, cold intolerance, dry skin, depression, bradycardia
• hyper: low TSH, high T3/T4. fatigue, weight loss, heat intolerance, hyperhidrosis (excessive sweating), nervousness, palpitations

flows through a closed system in the blood vessels