Pituitary DO

Question 1

HPA Axis hormones functions

Answer 1

1. respond to stress
2. thyroid stim, growth, reproduction

Question 2

Which pituitary gland is the producer? which is the storer?

Answer 2

Anterior - Producer
Posterior - Storer

Question 3

Anterior and Posterior Pituitary glands secrete which hormones?

Question 4

Growth hormone excess is referred to as _____
Growth hormone deficiency is referred to as _____

Question 5

what stim and inhibits Growth hormone secretion?

Answer 5

GHRH stim
Somatostatin inhibits

Question 6

High levels of growth hormone are usually caused by ____

Answer 6

a GH-secreting tumor

Question 7

what increases growth hormone secretion?

think big picture

Answer 7

Question 8

What decreases growth hormone secretion?

Answer 8

Question 9

Giantism vs Acromegaly
Which occurs during childhood?

Answer 9

Giantism = during childhood (b4 growth plates close)
Acromegaly = Adulthood

Question 10

genetic causes of Giantism

Answer 10

• familial isolated pituitary adenoma
  multiple endocrine neoplasia type 1 (MEN1)
• McCune-Albright syndrome (MAS)
• Carney complex with onset during
• prepubescence

Question 11

Giantism SS

Answer 11

• Longitudinal acceleration of linear growth secondary to insulinlike growth factor I (IGF-I) excess
• Tumor mass may cause headaches, visual changes due to optic nerve compression, and hypopituitarism
• Hyperprolactinemia is a common finding; it results from pituitary growth hormone (GH) excess,

Question 12

Acromegaly WU

Answer 12

• Two baseline GH levels are obtained prior to ingestion of 75 or 100 g of oral glucose, and additional GH measurements are made at 30, 60, 90, and 120 minutes following the oral glucose load. A rise, or no suppression is diagnostic.
• Measure serum GH 1 hour after oral administration of 100 g of glucose. Clearly elevated GH levels (>10 ng/mL) after oral glucose, combined with the clinical picture, secure the diagnosis of acromegaly, while a normal GH level (< 5 ng/mL) after oral glucose essentially excludes the diagnosis.

GnRH can be measured
IGF-I can be measured
Prolactin is often also measured since it can be co-secreted in 20% of tumors
Imaging: MRI of brain
CT scans of abdomen/pelvis or chest if brain is negative

Question 13

Acromegaly Complications

Question 14

Acromegaly Trmnt

Answer 14

• # 1 Trnassphenoidal Sx
• Radiation
• Octreotide -
• Bromocriptine -
• Pegvisomant (Somavert) -

Question 15

MC pituitary hormone deficiency in children

Answer 15

Growth Hormone Deficiency

Question 16

2 main ways you get pituitary dwarfism

Answer 16

1. Isolated LOW growth hormone
2. Generalized - ALL pituitary hormones are LOW

Question 17

Pituitary Dwarfism WU

Answer 17

• IGF-1 levels
• XR of LT Hand to determine bone age
• MRI to r/o calcifications, tumors, structural anomalies
• ACTH, 8 am serum cortisol level, LH, FSH, Prolactin levels

Question 18

Dx Criteria for Pituitary Dwarfism

Question 19

Dwarfism Trmnt

Answer 19

• recombinant Growth Hormone
• +/- other pituitary hormone replacement

Question 20

Which HPA hormones should be eval for deficiencies?

Answer 20

ALL
Cortisol
Thyroid
ADH
Sex hormone around time of puberty

Question 21

Why do new moms need to try breastfeeding ASAP

Answer 21

Stim Prolactin -> breastfeeding

Question 22

What stim prolactin secretion

Answer 22

• sleep
• stress
• pregnancy
• chest wall stimulation or trauma
• TRH, dopamine receptor antagonists, primary hypothyroidism
• prolactinomas (tumor)

Question 23

Approximately 75% of patients presenting with galactorrhea and amenorrhea have _____.

Answer 23

hyperprolactinemia

Question 24

Drugs that can cause Hyperprolactinemia

Answer 24

Dopamine-receptor antagonists (phenothiazines, butyrophenones, thioxanthenes, metoclopramide, sulpiride, pimozide)
Conventional and atypical antipsychotics (Haloperidol, risperidone{70-100%}, olanzapine, quetiapine, amisulpride)
Dopamine-depleting agents (methyldopa, reserpine)
Others (isoniazid, danazol, tricyclic antidepressants, monoamine antihypertensives, verapamil, estrogens, antiandrogens, cyproheptadine, opiates, H2-blockers [cimetidine], cocaine)

Question 25

Prolactin levels >_______ req brain imaging

Answer 25

100-250ng/mL ## Footnote Med induced will be high but under 100 usually

Question 26

why may you need a DEXA scan if you have Hyperprolactinemia?

Answer 26

persistent low estrogen/testosterone can lead to osteoporosis

Question 27

Initial drug of choice if hyperprolactinemia ET is pituitary in orgin

Answer 27

**Bromocriptine** (Dopamone AGONIST)

Question 28

Prolactin Deficiency is MC assosiated with post-partum _____ Syndrome

Answer 28

Sheehan ## Footnote postpartum pituitary necrosis necrosis of cells of the anterior pituitary gland following significant post-partum bleeding, hypovolemia, and shock.

Question 29

Mom lost a lot of blood during birth and is having trouble starting breastfeeding. Concern for?

Answer 29

Sheehan syndrome (postpartum pituitary necrosis) Prolactin deficiency ## Footnote Lose blood flow to anterior pituitary -> ischemia

Question 30

WU for prolactin deficiency

Question 31

Prolactin Deficiency trmnt

Answer 31

**Lifelong replacement of pituitary hormones:** Hypothyroidism can be treated with levothyroxine Cortisol deficiency can be treated with prednisone or hydrocortisone. Gonadotropin deficiency should be treated with estrogen if the uterus has been removed with a combination of estrogen and progesterone if a uterus is present. The growth hormone is probably the most common hormone that needs replacing, and the dosage must be individualized to the patient's need. For patients who develop diabetes insipidus, desmopressin (DDAVP)

Question 32

Excess ADH is ____

Answer 32

SIADH

Question 33

ADH deficiency is ____

Answer 33

Diabetes insipidus

Question 34

what does ADH do?

Answer 34

dont pee save water at collecting duct Vasoconstricts at high levels

Question 35

What incr and decr ADH secretion?

Question 36

Central Diabetes Insipidus (ADH Deficiency)

Question 37

Primary vs Secondary Central Diabetes Inspidus

Question 38

Non-central Diabetes Insipidus

Answer 38

* Nephrogenic Diabetes Insipidus - tubule receptors dont respond correctly to ADH * Psychogenic Polydipsia - drinking too much water -> kidney becomes insensitive to ADH (>6L)

Question 39

Water Deprivation Test

Question 40

Pt does water deprivation test. No urine concentration increase is seen. What may this be?

Answer 40

Diabetes insipidus

Question 41

Are those with psychogenic polydipsia able to concentrate their urine during water deprivation test?

Answer 41

YEs

Question 42

Tx for water deprivation test?

Answer 42

restrict fluid intake to ≤ 2 L/day Norm concentrating ability will return within several weeks

Question 43

Central Diabetes Insipidus (ADH Deficiency) Trmnt

Answer 43

Desmopressin (DDA VP) ## Footnote mimics endogenous vasopressin

Question 44

3 non-hormonal drugs that reduce polyuria?

Answer 44

1. Diuretics, primarily thiazides 2. Vasopressin-releasing drugs (eg, chlorpropamide, carbamazepine, clofibrate) 3. Prostaglandin inhibitors(NSAIDs)

Question 45

Chlorpropamide, carbamazepine, and clofibrate stimulates increased renal tubular water reabsorption (pee less). This is effective on which type(s) of diabetes Insipidus?

Answer 45

ONLY central diabetes insipidus. May even eliminate need for vasopressin! ## Footnote WONT work for nephrogenic diabetes insipidus bc their receptors are shot

Question 46

Nephrogenic Diabetes Insipidus Trmnt

Answer 46

Indomethacin (NSAIDs make you pee less) Na+ intake restriction Thiazide Diuretic

Question 47

ADH excess is referred to as ____

Answer 47

SIADH Syndrome of Innapropriate AntiDiuretic Hormone Secretion

Question 48

SIADH definition

Answer 48

Dilute serum (hyposmolarity) concentrated urine ## Footnote NO other physiological cause of vasopressin secretion Normally, low plasma osmolality inhibits vasopressin secretion, allowing the kidneys to produce dilute urine.

Question 49

Euvolemic vs Hypervolemic vs Hypovolemic Hyponatremia

Answer 49

* Euvolemic - norm water gain and loss (equalized free water) * Hypervolemic - water retention is greater (CHF, Cirrhosis) * Hypovolemic - Na+ loss is greater (MCC by renal diuretic like thiazide or extra renal causes)

Question 50

Which type of hyponatremia is SIADH?

Answer 50

Euvolemic Hyponatremia

Question 51

SIADH etiology

Question 52

SIADH WU

Question 53

SIADH Trmnt

Answer 53

Treatment of cause Fluid restriction Sometimes a vasopressin receptor antagonist Sometimes NS

Question 54

# SIADH Fluid Restriction only drink ____ L a day

Answer 54

250-500L ## Footnote Also give loop diuretic combo with IV 0.9% saline to slowly correct severe Na+ deficits without inducing vol overload

Question 55

If pt with SIADH cannot tolerate water restriction, giving ____ will unconcentrate the urine. However, it can cause acute kidney injury (AKI)

Answer 55

Demeclocycline