Endocrine pt 1 Thursday

Question 1

Are thyroid nodules benign? Explain

Answer 1

90% of nodules are benign
Often these are follicular adenoma or cysts. Only 10% are suspicious

Question 2

List the benign types of thyroid nodules

Answer 2

Follicular adenoma (colloid) most common type of thyroid nodule, accounting for 50-60%
Other: adenomas, cysts, localized thyroiditis

Question 3

Describe the clinical Sx of thyroid nodules

Answer 3

Most of the time, they are asymptomatic
May have compressive symptoms:
Difficulty swallowing or breathing
Neck, jaw, or ear pain
Hoarseness
Rarely, patients may develop a functional nodule which causes hyperthyroid symptoms

Question 4

Describe benign vs malignant thyroid nodules on PE

Answer 4

Benign: smooth, firm, irregular, sharply outlined, discrete, painless
Malignant: rapid growth, fixed, no movement with swallowing

Question 5

What type of testing do you need for thyroid nodules? Explain

Answer 5

Thyroid function testing:
1) You will order TSH, T3/T4 and ultrasound
-If TSH is in the subclinical hyperthyroid range or overtly hyperthyroid, then radioactive iodine uptake scan should be ordered in addition to ultrasound
>“Hot” nodules have a lower risk for malignancy but need to be treated
-Ultrasound will guide the need for FNA with biopsy

Question 6

“_____” thyroid nodules have a lower risk for malignancy but need to be treated

Answer 6

Hot

Question 7

Ultrasound interpretation of thyroid nodules:
1) Describe what would have high suspicion

Answer 7

Solid hypoechoic nodule, or a cyst with hypoechoic segment PLUS one of the following
1) Irregular margins, microcalcifications, taller than wide shape, evidence of extrathyroidal extension
2) Recommended FNA with bx if > than 1.0 cm

Question 8

Ultrasound interpretation of thyroid nodules:
Describe what would have intermediate suspicion

Answer 8

Hypoechoic solid nodule with smooth margins WITHOUT the following:
1) Microcalcifications, extrathyroidal extension, taller than wide shape
2) Recommended FNA with bx if > 1.0 cm

Question 9

Ultrasound interpretation of thyroid nodules:
Describe what would have low suspicion

Answer 9

Isoechoic or hyperechoic solid nodule, or partially cystic nodule with eccentric solid areas WITHOUT
1) Microcalcifications, extrathyroidal extension, taller than wide shape
2) Recommend FNA with bx if > 1.5 cm

Question 10

Ultrasound interpretation of thyroid nodules:
Describe what would have very low suspicion

Answer 10

1) Spongiform or partially cystic nodules WITHOUT any of the features described above
2) Recommend FNA with bx if > 2.0 cm

Question 11

Ultrasound interpretation of thyroid nodules:
Describe what you could say is benign

Answer 11

1) Purely cystic nodules with no solid component
2) No FNA with bx recommended

Question 12

List the 4 main types of thyroid cancer

Answer 12

1) Papillary
2) Follicular
3) Medullary
4) Anaplastic

Question 13

Papillary thyroid CA:
1) Describe the pathogenesis
2) Describe the pt profile

Answer 13

1) Most common and least aggressive cancer of the thyroid (80%)
2) More often female
Painless thyroid nodule
Had radiation exposure to the head and neck
Possible family history

Question 14

Papillary thyroid CA:
1) How do you Dx?
2) How do you Tx?

Answer 14

1) Fine needle aspiration
2) Thyroidectomy (near or total)
-Followed by post op levothyroxine
-+/- Post surgery radioactive iodine
-Monitor thyroid levels

Question 15

Follicular Thyroid Carcinoma:
1) Describe the pathogenesis
2) Describe the demographic

Answer 15

1) Second most common type of thyroid cancer (10%)
Associated with iodine deficiency
2) 40-60 years old

Question 16

Follicular Thyroid Carcinoma:
1) How do you Dx?
2) How do you Tx?

Answer 16

1) Fine needle aspiration with post surgical histologic testing
This will be done after thyroidectomy
2) Thyroidectomy (full or partial) > post op levothyroxine
+/- radioiodine
Monitoring of thyroid levels

Question 17

Medullary Thyroid Carcinoma: Describe the pathogenesis and prevalence

Answer 17

1) Cancer of calcitonin-synthesizing parafollicular cells
2) 5% of thyroid carcinoma
-90% of these are sporadic
-10% are associated with MEN IIa or IIb; RET mutation
2) May have ectopic production of ACTH, with a pheochromocytoma present in 50-70% cases, Hyperparathyroidism in 50%

Question 18

Medullary Thyroid Carcinoma:
1) How do you Dx?
2) How do you Tx?

Answer 18

1) FNA
-Increased calcitonin on lab
-On pathology- proliferation of parafollicular cells ( C cells) that produce excess calcitonin
-Check urinary metanephrine levels; Pheochromocytoma also associated with MEN II
2) Total thyroidectomy
Levothyroxine supplementation and monitoring

Question 19

Anaplastic Thyroid Carcinoma
1) Describe the pathogenesis
2) Describe the pt profile

Answer 19

1) Most aggressive + rarest thyroid cancer
Poorest prognosis
2) Rapid growth
Compressive symptoms; dyspnea
May invade the trachea
Dysphagia
Rock hard thyroid mass

Question 20

Anaplastic Thyroid Carcinoma:
1) How do you Dx?
2) How do you Tx?

Answer 20

1) Fine needle biopsy
2) Resection doesn’t work
Radiation or chemo
Palliative tracheostomy

Question 21

Describe PTH (parathyroid hormone)
1) What does it do?
2) What secretes it>?
3) What inhibits it? What stimulates the receptor on the gland?

Answer 21

1) Increases calcium when it’s low
-Causes the kidneys to excrete PO4
2) Secreted by parathyroid glands on back of thyroid whose default is “ON”
3) High calcium inhibits PTH release
Ca++ stimulates Ca receptor on gland

Question 22

What does PTH normally do to bone?

Answer 22

Bone resorption = taking Ca and Phosphate from bone
Does this through osteoclast activity

Question 23

What does the GI tract normally have to do with PTH?

Answer 23

Absorbs Ca and Phosphate
Does this through 1,25 Vit D (active form) secreted by kidney

Question 24

1) What does PTH normally do to the kidneys?
2) How does this affect urine?

Answer 24

1) Signals the release 1, 25 Vit D; tells kidney to resorb Ca and ELIMINATE Phosphate
-The kidney will waste more phosphate than is resorbed through bone or absorbed through GI tract
-Serum Ca++ is HIGH and Phosphate is LOW
2) Increase in urine phosphate
-Increase in URINE Calcium; yes, because there is so much Ca around, some still gets excreted

Question 25

Describe how the end product of vit D processing is created

Answer 25

D2 is the Vit D you eat UV light creates D3 - Vit D precursor in your skin Liver takes both forms and makes 25 Vit D which is still an intermediate form Kidney turns 25 Vit D into 1, 25 Vit D in the proximal convoluted tubule

Question 26

List some Sx of Hyperparathyroid

Answer 26

1) Bones: Osteoclast activity increased = watch for osteopenia and bone pain 2) Stones: Urine Calcium UP, urine phosphate UP > calcium phosphate and calcium oxalate kidney stones 3) Abdominal groans: Increased CA = constipation and pain 4) Psychic moans: Ca > encephalopathy -Note: most of the time, a Ca high enough to cause encephalopathy is actually caused by malignancy (not parathyroid hormone)

Question 27

List 2 causes of hyperparathyroid

Answer 27

MEN 1 syndrome Chromosome XI inversion

Question 28

What are 2 causes of hypoparathyroid? explain

Answer 28

The surgeon tried to resect some of the thyroid and cut out parathyroid glands or cut their vascular supply. . . LOW calcium Hyperactive nerves Calcium is not available to block sodium channels on neuron, increasing total activity

Question 29

List 3 Sx of hypoparathyroid

Answer 29

Perioral tingling Digital paresthesia Trousseau and Chvostek's sign

Question 30

List a bunch of Sx of hypercalcemia

Answer 30

-Muscle weakness -Fatigue -Volume depletion -Nausea and vomiting -Coma and death -Depression and confusion -Memory problems -Polydipsia/polyuria -Decreased appetite -Abd pain -Constipation -Acute pancreatitis -HTN -EKG- short QT -Left Ventricular Hypertrophy Kidney stones Asymptomatic

Question 31

Hypercalcemia: Describe the pathogenesis

Answer 31

1) Lab error! 2) Primary hyperparathyroidism most common -Parathyroid adenoma, MEN 3) Lithium therapy 4) Malignancy -PTH related protein

Question 32

Hypercalcemia: What will the pt be like? Explain

Answer 32

Usually, asymptomatic unless they have cancer and are delirious from extremely high calcium

Question 33

For every deviation of 1 on albumin, change Ca in opposite direction 0.8; give examples

Answer 33

1) Alb 4 -0-> CA lab is 10 and actually is 10 2) Alb 5 > Ca lab is 10.8 and actually is 10 3) Albumin 3 > Ca lab is 9.2 and actually IS 10! These equations show that the Ca is 10 You would confirm this with ionized calcium 4.65-5.25

Question 34

What if the ionized calcium is high? (even with correction)

Answer 34

Go looking for the cause

Question 35

Hypercalcemia: How do you Dx?

Answer 35

1) Repeat the lab! -Get ionized calcium! 2) Once confirmed elevation  get PTH and see if it’s high 3) You can get PTH related protein (which is what cancer emits) if the PTH is normal 4) You can check 1,25 Vit D and 24-hour urinary calcium -Calcium is high or high normal in hyperparathyroidism, and can be the same or VERY high in malignancy 5) Check an EKG

Question 36

How do you Tx hypercalcemia?

Answer 36

1) Mild hypercalcemia, which is < 12, does not often require treatment 2) Moderate to severe, >12: -IV fluids -IV fluids -IV fluids -IV loop diuretics – furosemide -In malignancy: calcitonin +/- bisphosphonates & Denosumab -In granulomatous disease: Steroids

Question 37

Primary Hyperparathyroidism: How is it diagnosed?

Answer 37

1) Kidneys “win” once stimulated by PTH 2) Therefore, calcium is HIGH and PO4 is low 3) On lab: High Calcium High PTH Low PO4

Question 38

Primary Hyperparathyroidism: How is it treated?

Answer 38

1) Surgery 2) Post op Sestamibi scans monitor subsequent parathyroid function

Question 39

What can happen with Untreated Hyperparathyroidism?

Answer 39

1) Osteoporosis 2) Kidney stones ( from excess calcium in blood- hard deposits can form in kidneys) 3) Cardiovascular disease assoc with hypercalcemia -Hypertension, arrhythmia

Question 40

Untreated Hyperparathyroidism: What are some findings on Xrays?

Answer 40

1) “Salt and pepper” skull 2) Distal clavicle resorption

Question 41

Hyperparathyroidism during Pregnancy: 1) How may it manifest? 2) Do fetuses have complications? Explain

Answer 41

1) May manifest as hyperemesis, pancreatitis, muscle weakness -Hypercalcemic crisis 2) 80% of fetuses experience complications -Fetal demise, preterm delivery, low birth weight -Neonatal tetany -Permanent hypoparathyroidism

Question 42

Secondary Hyperparathyroidism: Describe the main pathogenesis

Answer 42

Kidney disease: 1) Kidneys not making enough vit D 2) Nothing tells the gut to absorb Ca 3) Ca doesn’t inhibit PTH 4) Parathyroid glands proliferate and make lots of PTH

Question 43

Secondary Hyperparathyroidism: 1) Describe the pt presentation (main symptom) 2) Describe how to Dx 3) How do you Tx?

Answer 43

1) Bones get weak > osteomalacia 2) Phosphate would classically be low, but may be normal because kidneys aren’t filtering well -The above process is occurring to normalize low calcium to begin with, so calcium may be normal -Look for high creatine, high BUN, potentially low GFR 3) Treat the kidney disease

Question 44

Secondary Hyperparathyroidism: 1) Describe the Vit D deficiency pathogenesis

Answer 44

Low vit D = Calcium is not being resorbed  calcum begins to lower PTH goes high Calcium trands back toward normal PO4 should be low because the kidneys have not trouble dumping it

Question 45

Secondary Hyperparathyroidism bc of Vit D def: 1) Dx? 2) Tx?

Answer 45

1) Check 25 vit D Not 1,25 – that one is too variable and changes based on PTH 2) Give them Ca and Vit D

Question 46

slide 91

Answer 46

PTH is absent- either by parathyroid injury (after thyroid surgery) or hereditary (DiGeorge syndrome) PTH is ineffective (intestinal malabsorption, pseudohypoparathyroidism) PTH is overwhelmed (acute renal failure, or rhabdomyolysis, or septic shock) Primary hypoparathyroidism- lifelong risk of symptomatic tetany without access to calcium- a patient may die

Question 47

slide 92

Answer 47

Lab Ca is 6-7 or lower

Question 48

Describe the pt in hypoparathyoidism

Answer 48

paresthesia of lips, tongue, fingers, feet Carpopedal spasm- Trousseau’s sign Spasm of facial muscles Fatigue Anxiety Hoarseness Wheezing Could have slowly developing mild diffuse encephalopathy. Suspect in any patient with unexplained dementia or psychosis

Question 49

Hypoparathyroidism: Describe the Tx

Answer 49

Acute attack of tetany- IV calcium gluconate Administer calcium 1 to 2 grams/day Calcitriol (0.25- 1 ug/day)- ( Vitamin D as soon as calcium rx started) Adjust according to serum calcium levels and urinary excretion. Restoration of magnesium stores may be required to reverse hypocalcemia if severe hypomagnesemia is present.