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Flashcards in Endocrine Deck (83):
1

What 2 electrolyte abnormalities cause nephrogenic DI?

High calcium
Low potassium

*Block ADH's effect on kidney

2

2 ways pituitary can be damaged?

Compression (tumors)
Damage (trauma, radiation, stroke, infection)

3

Prolactin deficiency manifestations in women & men?

Women: NO lactation after delivery
Men: nothing

4

LH or FSH deficiency manifestations in women & men?

Women: amenorrhea (no ovulation or menstruation)
Men: erectile dysfxn & decreased muscle mass

Both = decreased libido

5

What normally inhibits release of prolactin?

Dopamine

6

Decreased FSH/LH from decreased GnRH w/ anosmia?

Kallman syndrome

7

GH deficiency in women & men?

Children: short stature
Adults: few symptoms (other stress hormones available)

8

What electrolyte abnormality is common in panhypopituitarism?

Hyponatremia (low sodium): from hypothyroidism & isolated glucocorticoid underproduction

Potassium is NORMAL b/c aldosterone excretes potassium

9

Explain Metyrapone test?

Metyrapone (-) 11-B hydroxylase = no cortisol release in normal person = ACTH levels rise in normal person

In panhypopituitarism, this test causes no change in ACTH (pituitary not working)

10

Explain insulin test?

Normally, insulin decreases glucose and GH (stress hormone) should rise

In panhypopitutarism, don't have rise of GH

11

What hormone is affected in DI? Explain difference in central vs nephrogenic?

ADH

Central: no ADH release, but kidney is fine
Nephrogenic: normal ADH, kidney unresponsive to it

12

Common causes of nephrogenic DI?

Hypercalcemia
Hypokalemia
Lithium
Amyloidosis
Myeloma

13

Explain serum and urine findings for Na levels and osmolarity?

Serum Na = high (water loss)
Serum osm = high (water loss)
Urine Na = low (dilute)
Urine osm = low (dilute)

14

What symptoms result from hypernatremia?

CNS
Confusion, disorientation, lethargy, coma

15

Vasopressin effect on central vs nephrogenic DI?

Central: urine becomes concentrated and serum less dilute (ADH can work on functioning kidney)

Nephrogenic: NO changes (still dilute urine b/c no effect of ADH on kidney)

16

Treatment for central & nephrogenic DI?

Central: vasopressin (desmopressin)
Nephrogenic: correct underlying cause (hypercalcemia, hypokalemia)
*HCTZ, amiloride, NSAIDs --> alters renal countercurrent concentrating ability and causes concentration of urine / NSAIDs block prostaglandins

17

Most common cancer associated w/ acromegaly?

Colon cancer

18

Signs of acromegaly?

Increasing hat, ring, shoe size
Carpel tunnel
Teeth widening
Deep voice
Body odor
Joint pain

19

Best initial test for acromegaly?

IGF level

20

What hormone is co-secreted w/ GH?

Prolactin

21

Tx of choice for acromegaly?

1) Surgery
2) if surgery fails --> medication (pegvisomant = GH receptor blocker)

22

Causes for hyperprolactinemia?

Co-secretion w/ GH
Hypothyroidism --> high TRH level stimulates prolactin secretion
Pregnancy
Antipsychotic drugs
Methyldopa
Opioids
Verapamil

23

Signs of hyperprolactinemia in women and men?

Women: galactorrhea, AMENORRHEA, infertility
Men: erectile dysfxn, decreased libido

24

Diagnostic tests for hyperprolactinemia?

Thyroid function tests
PREGNANCY test
BUN/Ct (kidney disease elevates prolactin)
LFTs (cirrhosis elevates prolactin)

25

Treatment of hyperprolactinemia?

Dopamine agonists --> Cabergoline

26

What drug causes hypothyroidism?

Amiodarone

27

Hypothyroidism SLOWS everything down in the body except what?

Menstrual flow (increased)

28

Thyroid studies in hypothyroidism?

Tx for hypothyroidism?

Elevated TSH
Low T4

Tx: levothyroxine (synthroid)

29

What form of hyperthyroidism has eye and skin findings? What are they?

Best initial therapy?

Graves disease --> most common cause of double vision over 50 yo
*TSH receptor autoantibodies

Proptosis
Myxedema

Initial therapy = STEROIDS (decrease glycosaminoglycan deposition behind the eyes)

30

Form of hyperthyroidism with:
Tender nodule?
High TSH?

Tender nodule = subacute thyroiditis

High TSH = pituitary adenoma

31

Treatment for:
Graves?
Subacute thyroiditis?

Graves = radioactive iodine
Subacute = aspirin

32

Treatment of thyroid storm/acute hyperthyroidism?

1) Propranolol --> inhibits target organ effect, inhibits peripheral conversion of T4 --> T3

2) Methimazole or PTU

3) Iodinated contrast material - blocks peripheral conversion of T4 --> T3 and blocks release of existing hormone (acts to clog up the thyroid gland)

33

If a thyroid nodule is found, what is first thing to assess?

1) Is it HYPER-functioning by TSH/T4
2) If normal = biopsy

34

First sign to presence of Diabetes Insipidus (DI)?

High volume NOCTURIA

35

MEN 2A characterized by what 3 entities?

MEN 2B characterized by what 2 entities?

MEN 2A:
1) Medullary thyroid cancer
2) Pheo
3) Hyperparathyroidism (high calcium)

MEN 2B:
1) Medullary thyroid cancer
2) Pheo
3) Ganglioneurmatosis

36

Why are Cushing syndrome/disease patients at increased risk of DVT?

Increased Factor 8 and vWF complex with decreased fibrinolytic activity

37

Hypothyroidism can cause what metabolic abnormalities?

Hyperlipidemia --> due to decreased LDL surface receptors and/or decreased LDL receptor activity

38

Treatment of AFib in hyperthyroidism?

B-blocker (because of increased sensitivity of beta-receptors to sympathetic stimuli)

39

Diabetes medication that is also used for weight loss?

GLP-1 agonist (glucagon like peptide)

*some association w/ pancreatitis

40

What hormone is elevated in patients with androgen-producing adrenal tumors?

DHEA-S

41

What are Charcot joints?

What are exam findings?

Neuropathic damage from diabetes or syphilis resulting in loss of feeling --> progressive damage to feet

Deformity, joint damage w/ swelling and osteophytes on xray

42

How will TSH, T3/T4, and radioactive nucleotide uptake values look in exogenous thyroid hormone ingestion?

Factitious thyrotoxicosis --> NO goiter or exophthalmos
LOW TSH
HIGH T3/T4
RAIU LOW

43

Person with hypothyroidism develops amenorrhea and galactorrhea - why?

What other neurotransmitter can cause the same effects?

Hypothyroidism --> increased secretion of TRH (which stimulates TSH) --> TRH (+) prolactin secretion = amenorrhea/galactorrhea

*Serotonin & TRH

44

After surgery, person develops tachycardia, HTN, fever, tremor in her hands, altered mental status, and lid lag. What is it? What is best initial test?

Thyroid storm

Thyroid function tests & propranolol

45

What presents as galactorrhea and amenorrhea in women and hypogonadism in men?

What is the primary treatment?

Prolactinoma

*Dopamine agonists --> dopamine (-) prolactin secretion
Bromocriptine, cabergoline

46

What is non-ketotic hyperosmolar syndrome?

What other systemic effects can it cause?

Stress situations (e.g. infection) causes elevation of cortisol and catecholamine levels --> increased glucose levels WITHOUT ketonuria

The hyperglycemia causes osmotic diuresis --> serum hyperosmolarity

Acute hyperglycemia can cause blurred vision due to myopic increase in lens thickness and intraocular hypotension secondary to hyperosmolarity

47

27 male started on thiazide after coming to ER with BP of 157/93. He later develops hypokalemia while his BP remains elevated. What is the next best step in evaluation?

Serum renin and aldosterone levels

48

How does a pituitary adenoma respond to dexamethasone suppression test?

Is suppressed ONLY with HIGH dose dexamethasone!

49

14 yo with Type 1 DM has recent onset fatigue and rash over extensor surfaces of knees and elbows. Labs show Fe-def anemia. What is an appropriate co-screen for this patient?

anti-Tissue Transglutaminase antibodies

**Celiac disease associated with T1DM**

50

How does estrogen affect thyroid levels?

Estrogen increases SHBG and decreases the clearance of TBG --> causes increased TBG levels and binds up free T4 in circulation

**if on Estrogen and patient is hypothyroid -- need to give MORE levothyroxine!!

51

Most common cause of thyrotoxicosis with reduced thyroid uptake?

Subacute granulomatous thyroiditis

*Intense thyroid pain

52

Untreated hyperthyroidism can result in what 2 conditions?

Rapid bone loss (increased osteoclast activity)
AFibrillation

53

What treatment modality for Graves disease can initially worsen the exophthalmos?

Radioactive iodine --> first few days after RAI, the destroyed thyroid cells release excess thyroid hormone that can temporarily worsen hyperthyroid state

54

Which anti-thyroid medication causes hepatic failure?

PTU

55

Person has s/s of myasthenia gravis. What are the appropriate confirmatory tests?

What following test should be ordered?

EMG and ACh-antibody receptor test

**CT of chest --> screen for THYMOMA!!!

56

In diabetes, what is the first change to occur in the kidneys?

Glomerular hyperfiltration

ACEi help REDUCE intraglomerular hypertension by dilating Efferent arteriole

57

56 yo woman recent developed diabetes and has had wt loss over 6 months with occasional watery diarrhea. She also has eczematous rash around her mouth that has spread to the R thigh - it now appears as erythematous plaques with central clearing and eroded borders. What is the cause?

Glucagonoma

*Causes diabetes (high blood sugar), necrolytic migratory erythema, diarrhea, wt loss

58

What are the criteria for metabolic syndrome?

How many need to be present?

3 of these 5

1) Abdominal obesity > 40 in (men) >35in (women)
2) Fasting glucose > 100-110
3) BP > 130/80
4) Triglycerides >150
5) HDL

59

How can you differentiate between insulinoma or exogenous insulin use?

C-peptide and proinsulin levels

*C-peptide is cleaved from insulin released from pancreas --> NOT present in exogenous insulin!

60

Proper order of treatment for pheo?

1) a-blocker (prevent unopposed alpha stimulation and increased BP)

2) b-blocker

61

Side effect of methimazole?

Agranulocytosis

62

Episodic flushing is hallmark for what?

Other s/s?

Diagnostic test?

Carcinoid syndrome

Flushing, diarrhea, telangectasias, bronchospasm

*Tricuspid regurgitation --> common heart defect

5-HIAA in urine

63

How to differentiate the MEN syndromes?

MEN 1 = 3 P's 0 M (Parathyroid, Pancreas/ZE, Pituitary)
MEN 2a = 2 P's 1 M (Parathyroid, Pheo, MTC)
MEN 2b = 1 P 2 M's (Pheo, MTC, Mucosal neuroma, Marfan-like)

64

40 yo man has episodes of palpitations, anxiety, and sweating and he also has hypermobile joints. He has a family hx of thyroid cancer. He has a 4-cm hard thyroid nodule. He also has elevated serum calcitonin and metanephrines. What else must you look for?

What gene is implicated?

Mucosal neuromas

*MEN 2B --> MTC, Pheo, Mucosal neuromas, Marfanoid features

RET proto-oncogene

65

Electrolyte abnormality in DKA?

Hyperkalemia --> acidosis causes H+ to move intracellularly in exchange for K moving outward

66

What are common s/s in hypothyroidism?

Weight gain
Fatigue
Constipation
Concentration changes

67

In someone with hypocalcemia, what initial causes should be considered?

Hypoalbuminemia
Hypomagnesiemia
Recent blood transfusion (citrate)
Drugs (phenytoin, bisphosphonates)

68

What should you consider in hypocalcemia with elevated PTH?

Vit D deficiency, chronic kidney disease

*Check creatinine to r/o kidney disease + check 25-hydroxy vitamin D levels

69

If someone has muscle weakness, slowed DTRs, and elevated serum CK, what should be the first initial test?

How is this different than polymyositis?

TSH/free T4
*SLOW DTRs
Can be proximal muscles, myalgias

*Polymyositis = normal DTRs

70

Person has unexplained elevated CK + myopathy?

Hypothyroidism

71

What s/s suggest primary adrenal insufficiency?

What initial test?

Confirmatory test?

Hyponatremia, hyperkalemia, anemia
*Increased pigmentation

Basal early morning cortisol & ACTH --> if low cortisol levels need to do confirmatory test

Confirm with Cosyntropin (synthetic ACTH) --> if NO increase in cortisol after administration = Addison

72

Synthetic analogue of ACTH?

Analogue of ADH?

Cosyntropin

Vasopressin

73

What electrolyte abnormality is common in chronic steroid use (Cushing syndrome)?

Hypokalemia

*Corticosteroids have some mineralocorticoid activity and will bind to aldosterone receptors in the kidney

74

22 yo has hyperthyroidism. She begins PTU therapy. 2 weeks later, she returns with sore throat. She is febrile and exam shows soft palate, pharynx, and tonsils are red and swollen. What is next best appropriate step?

STOP PTU --> agranulocytosis can occur --> low WBC and infections can result

75

What antibodies are most prevalent in:

Hashimoto's?
Graves?

Hashimoto's = anti-thyroid peroxidase (anti-TPO), anti-thyroglobulin antibody

Graves = thyroid-stimulating immunoglobulins (TSI) --> stimulate TSH receptors

76

A person with carcinoid syndrome is at risk for developing a deficiency in what vitamin or mineral?

Niacin

*Serotonin is made in carcinoid cells from tryptophan --> tryptophan is used in the production of niacin
Increased tryptophan conversion to serotonin and 5-HIAA = less niacin production

77

Hashimoto's thyroiditis predisposes you to increased risk of developing which thyroid disorder?

Thyroid lymphoma

78

Person with TB develops low Na, elevated K and low glucose on labs. What acid base disturbance would be expected?

Normal anion-gap metabolic acidosis

*TB common cause of adrenal insufficiency (Addison)

*AI --> high K+, high H+, low Na, low glucose
- Aldosterone deficient = normally acts to save sodium (reabsorption) and secrete K+ and H+
*No aldosterone = increased K+ and H+ with low Na

79

Acne-like eruption characterized by erythematous follicular papules on the face, trunk, extremities and comedones are NOT present. What is the cause?

Steroid use

80

20 yo male with mild gynecomastia and enlarged spleen. Labs show elevated Hct with normal WBC and platelet count. What is the most probable cause?

Steroid drug abuse (androgens are steroid-derived)

*Gynecomastia, testicular atrophy, aggressive behavior
*Erythrocytosis, hepatotoxicity

81

38 yo male on steroids for sarcoidosis develops progressive R hip pain present on wt bearing and at rest. He has signs of Cushing disease. What is the most likely cause of his hip pain?

Disruption of bone vasculature from steroid use

82

Person has palpitations and wt loss, HTN and tachycardia. Thyroid has 2x2cm L-sided thyroid nodule. T3/T4 are elevated and TSH is undetectable. RAI scan shows uptake in L thyroid nodule; remained of thyroid is reduced. What is the most likely diagnosis?

Toxic adenoma

*Thyroxicosis = RAI shows uptake in adenoma only with remainder of gland suppressed

83

Pathophys behind familial hypocalciuric hypercalcemia?

Abnormal Ca-sensing receptors on the parathyroid cells and renal tubules
Parathyroid --> blocks normal Ca-induced PTH suppression = high/normal PTH levels
Renal tubules --> defective Ca-sensing receptors cause excess Ca reabsorption = LOW urinary Ca levels

Urine Ca/Cr ratio =