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Flashcards in Endocrine Deck (80):
1

Causes of decreased Mg

Diarrhea, Aminoglycosides, Diuretics, Alcohol abuse

2

Control of blood flow to parathyroids?

Cervical sympathetic ganglia control blood flow to parathyroids

3

How does PTH activate osteoclasts?

PTH binds osteoblasts and causes increased production of macrophage colony stimulating factor and RANK-L --> RANK-L binds RANK receptor on osteoclasts to stimulate them and increase Ca

4

Where are parafollicular cells derived from?

Neural crest

5

Which endocrine hormones signal through cAMP?
FLATChAMP

FSH, LH, ACTH, TSH, CRH, hCG, ADH (V2), MSH, PTH, Calcitonin, GHRH, Glucagon

6

Which endocrine hormones signal through cGMP?
(Vasodilators)

ANP, BNP, NO (EDRF)

7

Which endocrine hormones signal through IP3?
GOAT HAG

GnRH, Oxytocin, ADH (V1), TRH, Histamine (H1), Angiotensin II, Gastrin

8

Which endocrine hormones signal through intracellular receptors? VETTT CAP

Vitamin D, Estrogen, Testosterone, T3/T4, Cortisol, Aldosterone, Progesterone

9

Which endocrine hormones signal though intrinsic tyrosine kinase?

Insulin, IGF-1, FGF, PDFG, EGF (think growth factors)

10

Which endocrine hormones signal through receptor-associated tyrosine kinase?
PIGG(L)ET

Prolactin, Immunomodulators (IL-2, IL-6, IFN), GH, G-CSF, Erythropoietin, Thrombopoietin

11

Functions of T3 hormone (4 B's)

Brain maturation
Bone growth (synergism with GH)
B-adrenergic effects (increased B1 receptors in heart = CO, HR, SV, contractility)
Basal metabolic rate increases (via increased Na/K ATPase activity --> increases O2 consumption, RR, body temp)

12

Mechanism of Propylthiouracil
Mechanism of Methimazole

Propylthiouracil inhibits peroxidase (oxidation and organification of iodide, coupling of MIT and DIT) and 5-deiodinase (converts T3 to T4)
Methimazole inhibits peroxidase only

13

What is the Wolff-Chaikoff effect?

Excess iodine temporarily inhibits thyroid peroxidase --> decreases iodine organification and T3/T4 production
-The reason Iodine can be used to treat hyperthyroidism

14

What is metyrapone stimulation used for?

Metyrapone blocks the last step of cortisol synthesis (11 deoxycortisol --> cortisol)
Normal response is a decrease in cortisol and compensatory increase in ACTH but in adrenal insufficiency ACTH remains decreased after test

15

What do you see in urine of patient with neuroblastoma?

Homovanillic acid (HVA) - breakdown product of dopamine
Vainllylmandelic acid (VMA) - breakdown product of NE

16

Stains for neuroblastoma

Bombesin and neuron-specific enolase positive

17

EPO secreting tumors

Renal cell carcinoma
Hepatocellular carcinoma
Pheochromocytoma
Hemangioblastoma

18

Rule of 10s for pheochromocytoma

10% malignant
10% bilateral
10% extra-renal (bladder wall)
10% calcify
10% kids

19

Associations of pheochromocytoma

Neurofibromatosis type 1
Von Hippel Lindau
MEN 2A and 2B

20

Urine of patient with Pheochromocytoma

Increased catecholamines and metanephrines in urine and plasma (vanillylmandelic acid)

21

Treatment for pheochromocytoma

IRREVERSIBLE alpha antagonist - Phenoxybenzamine followed by beta blocker prior to tumor resection

22

Increased CK from myopathy (w/o myoedema)

Hypothyroidism

23

Lab findings in hypothyroidism

Increased TSH
Decreased free T3 and T4
Hypercholesterolemia (from decreased LDL receptor expression)

24

Granulomatous inflammation of thyroid

Subacute thyroiditis (de Quervain)

25

Tender thyroid

Subacute thyroiditis (de Quervain)

26

Thyroid replaced by fibrous tissue

Riedel thyroiditis

27

IgG4 related systemic disease manifestations

Autoimmune pancreatitis
Retroperitoneal fibrosis
Non-infectious atrocities
Riedel thyroiditis

28

Rock like painless goiter

Riedel thyroiditis

29

Treatment for Thyroid storm

Propranolol
Propylthiouracil
Prednisolone

30

Ovarian tumor that presents as hyperthyroidism

Struma ovarii teratoma

31

How do beta blockers treat thyrotoxicosis?

Decreased peripheral conversion of T4 --> T3 by inhibiting iodithyronine deiodinase and block beta adrenergic receptors --> decrease HR and agitation

32

Complications of thyroid surgery

Hoarseness (recurrent laryngeal nerve damaged)
Hypocalcemia (removal of parathyroid glands)
Transection of recurrent and superior laryngeal nerves (during ligation of inferior thyroid artery and superior laryngeal artery)

33

Large cells with overlapping nuclei containing finely dispersed chromatin (empty nuclei with central clearing)

Orphan annie nuclei

34

Orphan annie nuclei and psammoma bodies

Papillary carcinoma of thyroid

35

Difference between follicular adenoma and follicular carcinoma

Carcinoma invades thyroid capsule
FNA can't distinguish

36

Tumor that produces Calcitonin

Medullary carcinoma of thyroid

37

How does medullary carcinoma of thyroid spread?

Hematogenous spread

38

Cancer associated with Hashimoto thyroiditis

Lymphoma (rapidly enlarging neck mass)

39

Albright hereditary osteodystrophy

Pseudohypoparathyroidism = unresponsiveness of kidney to PTH
Hypocalcemia, shortened 4th/5th digits, short stature
PTH levels are high

40

Familial hypocalciuric hypercalcemia

Defective Ca sensing receptor on parathyroid cells
PTH cannot be suppressed by increased Ca level --> mild hypercalcemia with normal to increased PTH levels

41

Calcium levels in acute pancreatitis

Hypocalcemia - Ca precipitates out of abdomen

42

Lab findings in primary hyperparathyroidism

Increased PTH
Hypercalcemia
Hypercalciuria
Hypophosphatemia
Increased ALP (sign of osteoblast activity)
Increased cAMP in urine

43

Chronic renal failure labs

Hypocalcemia
Hyperphosphatemia (can't excrete it)
Increased PTH

44

Lamellar bone structure resembling mosaic pattern

Pagets

45

Osteoid matrix accumulation around trabeculae

Vit D deficiency

46

Spongiosa filling medullary canals with no mature trabeculae

Osteopetrosis

47

Trabecular thinning with few connections

Osteoporosis

48

Treatment for prolactinoma

(Dopamine agonists)
Bromocriptine
Cabergoline

49

GH effects on glucose

GH decreases glucose uptake
Can cause secondary diabetes

50

Most common cause of death in Acromegaly

Heart failure

51

Treatment for Acromegaly

Removal of pituitary adenoma
Octreotide (somatostatin analog)
Pegvisomant (growth hormone receptor antagonist)

52

Diagnosis of Diabetes Insipidus

Urine specific gravity 290 mOsm/kg
Hyperosomotic volume contraction

53

Treatment of Central DI

Intranasal desmopressin acetate
Hydration

54

Treatment of Nephrogenic DI

HCTZ, Indomethacin, Amiloride
Hydration

55

How does body respond to water retention in SIADH?

Body responds with decreased aldosterone (hyponatremia) to maintain near-normal volume status

56

Causes of SIADH

Trauma to head/CNS disorders
Ectopic ADH (small cell lung cancer)
Pulmonary disease
Drugs (Cyclophosphamide)

57

Treatment of SIADH

Fluid restriction
IV hypertonic saline
Conivaptan - ADH antagonist
Tolvaptan - ADH antagonist
Demeclocycline - ADH antagonist

58

What is pituitary apoplexy?

Sudden hemorrhage of pituitary gland - often in presence of existing pituitary adenoma

59

Secondary diabetes

Due to unopposed secretion of GH and epinephrine

60

Complications of diabetes mellitus

1. Nonenzymatic glycation: a. small vessel disease causes retinopathy, glaucoma, neuropathy, nephropathy and b. large vessel disease atherosclerosis, CAD, peripheral vascular occlusive disease, gangrene
2. Osmotic damage: sorbitol accumulation in organs with aldose reductase and absent orbital dehydrogenase --> neuropathy and cataracts

61

What is Kussmaul breathing?

The body's way of compensation for metabolic acidosis; trying to breathe off CO2 - happens in Diabetic ketoacidosis; rapid deep breathing

62

Why is there hyperkalemia in DKA?

H+/K+ exchanger is trying to pull H+ into cells because of metabolic acidosis --> then Kidney compensates and gets rid of K+ so total body K+ will be low

63

Why does hyperosmolar coma happen in type 2 DM instead of DKA?

There is some insulin in Type 2 so the insulin prevent lipolysis, B oxidation and ketone production

64

a. Histology of Type 1 DM
b. Histology of Type 2 DM

a. Islet leukocytic infiltrate
b. Islet amyloid polypeptide (IAPP) deposits

65

Precipitating factors of DKA

Increased insulin requirements due to stress (infection)

66

Complications of DKA

Mucormycosis
Cerebral edema
Cardiac arrhythmias
Heart failure

67

Dermatitis, Diabetes, DVT, Depression and Anemia

Glucagonoma

68

Treatment of hypoglycemia

In medical setting - IV glucose
In emergency non-medical setting - IM glucagon

69

Necrolytic Migratory Erythema

Seen in Glucagonoma
Erythematous papules, plaques on face/perineum/extremities
Lesions enlarge and coalesce leaving a bronze colored, central indurated area with blistering/scaling

70

5-Hydroxyindoleacetic acid (5-HIAA) in urine

Carcinoid syndrome

71

MEN 1

Parathyroid tumors (100%)
Pituitary tumors (prolactin or GH)
Pancreatic endocrine tumors (ZE, insulinoma, VIPomas, glucagonomas)

72

MEN 2A

Parathyroid hyperplasia (20%)
Pheochromocytoma (45%)
Medullary thyroid carcinoma (secretes calcitonin)
Associated with marfanoid habitus (mutation in RET gene)

73

MEN 2B

Pheochromocytoma
Medullary thyroid carcinoma
Oral/intestinal ganglioneuromatosis (Mucosal neuromas)
Associated with Marfanoid habits (mutation in RET gene)

74

Septicemia, DIC, adrenal hemorrhage, petechial rash

Waterhouse-Friderichsen syndrome from N. meningitidis

75

Derivatives of neural crest cells

Chromatin cells
Parafollicular cells of thyroid
Schwann cells
Autonomic nervous system
Dorsal root and celiac ganglia
Melanocytes
Cranial nerves
Pia and arachnoid
Odontoblasts
Skull bones
Aorticopulmonary septum

76

N-myc oncogene overexpression and homer-wright rosettes

Neuroblastoma

77

Drugs that cause hypothyroidism

Lithium - inhibits uptake and organification of iodine by thyroid gland and inhibits peripheral conversion of T4 to T3
Amiodarone

78

Plasma antimicrosomal (antiperoxidase) antibodies and lymphocytic infiltrate

Hashimoto's thyroiditis

79

Gestational diabetes predisposes newborns to what?

Macrosomia
Hypoglycemia
Respiratory distress syndrome (Insulin inhibits surfactant synthesis)

80

What is Whipple's triad?

Hypoglycemia
Symptoms that are attributed to hypoglycemia
Resolution of symptoms with eating