Endocrinology Flashcards

1
Q

General Principals

What does dopamine inhibit? (2)

A

TSH and prolactin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

General Principals

What does somatostatin inhibit? (2)

A

TSH and GH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

General Principals

TRH stimulates what two things?

A

TSH and prolactin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

General Principals

What lab abnormalities are seen in patients with increased aldosterone levels? (3)

A

Hypokalemia
Metabolic alkalosis
Hypernatremia - Volume Expansion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Calcium and Bone Disorders

MEN 1

A

3 Ps

Parathyroid adenoma/hyperplasia
Pancreatic tumors
Pituitary adenoma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Calcium and Bone Disorders

MEN 2A?

A

2P - Pheochromocytoma/Parathyroid adenoma/Medullary thyroid cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Calcium and Bone Disorders

Men 2B?

A

1P
Pheochromocytoma
Marnoid body habitus/Mucosal neuromas
Medullary thyroid cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Calcium and Bone Disorders

What do MEN 2a and 2b have in common?

A

Both have pheochromocytoma and medullary thyroid cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Calcium and Bone Disorders

HCTZ causes what in terms of hypercalcemia?

A

High normal or modestly elevated calcium levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Calcium and Bone Disorders

Describe pathogenesis of secondary hyperparathyroidism?

A

Secondary hyperparathyroidism is from ESRD/CKD which causes an increase in serum phosphorus and decreased calcium (calcium level can also be normal). This triggers increased PTH secretion (becomes a feedback loop)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Calcium and Bone Disorders

Describe treatment guidelines in secondary hyperparathyroidism in relation to phosphorous?

A

Hyperphosphatemia - dietary phosphorus restriction (< 900 mg/day). If phosphorus is still elevated, use non-calcium containing phosphorus binders (sevelamer).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Calcium and Bone Disorders

Describe treatment guidelines in secondary hyperparathyroidism in relation to Calcium?

A

Don’t treat with calcium replacement if serum calcium > 7.5. Overtreatment may cause vascular calcification with calciphylaxis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Calcium and Bone Disorders

Describe treatment guidelines in secondary hyperparthyroidism in relation to PTH?

A

If serum PTH > 300, use vitamin D analogs like calcitriol or calcimimetic (cinacalcet)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Calcium and Bone Disorders

Name of Active Form of Vitamin D

A

Active Form of Vitamin D = 1,25-OH-Vitamin-D = Calcitriol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Calcium and Bone Disorders

Three functions of Active Form of Vitamin D

A

Calcitriol (1,25-OH-Vit-D) functions:
1. Decrease PTH
2. Increase Calcium
3. Increase Phosphorous

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Calcium and Bone Disorders

How is vitamin D processed by the body?

A

Vitamin D is observed via diet or sunlight. It goes to the liver where it is hydroxylated to form 25-OH-Vitamin-D. It goes to the kidneys where it is hydroxylated to form active vitamin D, aka calcitriol aka 1,25-OH-Vit-D.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Calcium and Bone Disorders

Three function of PTH?

A
  1. Increase Calcium
  2. Decrease Phosphorous
  3. Increase 1,25-OH-Vitamin-D via acting on the kidneys
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Obesity

What is normal BMI?

What is BMI cutoff for Obesity?

A

Normal BMI = 18.5-24.9

BMI cutoff for obesity = > 30

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Obesity

When is bariatric surgery considered for obesity patients? (2)

A
  1. Patients with a BMI > 40
  2. Patients with a BMI > 35 with > 1 severe weight related diseases/complications who have not met weight-loss goals with exercise, diet, and medications
20
Q

Calcium and Bone Disorders

What does Calcitonin do? (2)

What stimulates production of Calcitonin?

A

PTH antagonist
1. Slows down bone resorption
2. Increases calciuria

Calcitonin is increased when there is hypercalciemia present.

21
Q

Calcium and Bone Disorders

Causes of hyperparathyroidism? (3)

A
  1. Solitary adenomas of parathyroid glands (80% of causes)
  2. Hyperplasia of all four parathyroid glands
  3. Carcinoma of the parathyroid gland
22
Q

Calcium and Bone Disorders

Symptoms of Hypercalcemia

A

Bones, Stones, Abdominal Moans, and Psychic Groans

  1. Bones - increased risk of fractures, bone aches, and pain
  2. Stones - increased risk of calcium containing kidney stones
  3. Abdominal moans - constipation, nausea, anorexia, abdodminal pain
  4. Psychic groans - confusion, memory loss, and delirium

Other symptoms - **polyuria, polydipsia, shortened QT interval **

23
Q

Calcium and Bone Disorders

Causes of increased PTH/normal PTH and hypercalcemia? (3)

AKA PTH dependent hypercalcemia

A
  1. Primary hyperparathyroidism
  2. Familal hypocalciuric hypercalcemia
  3. Lithium
24
Q

Calcium and Bone Disorders

Can a patient with primary hyperparathyroidism have a normal PTH?

A

Yes, patients with a normal intact PTH with an elevated calcium level is still comptabile with the diagnosis of hyperparathyroidism

25
Q

Calcium and Bone Disorders

What are next steps in patients with hypercalcemia and high or normal PTH?

A

Measure 24-hour urinary calcium and creatinine excretion. Urinary calcium excretion is low in familal hypocalciuric hypercalcemia but normal to high in primary hyperparathyroidism.

26
Q

Calcium and Bone Disorders

Treatment of Hypercalcemia

A
  1. Aggressive volume resuscitation with normal saline (3-4L of NS)
  2. Calcitonin will take effect rapidly but action is short lived (tachyphylaxis).
  3. Only use loop diuretics if patient develops volume overload from saline resuscitation
  4. Bisphosphonates - take effect over several days. Paamidronate and zoledronic acid take effect in 48 hours.

Glucocorticoids if concerned about sarcoidosis or other granulomatous disorders

**Discontinue thiazide diuretics **

27
Q

Calcium and bone disorders

Side effect of bisphonate therapy?

A
  1. Osteonecrosis of the jaw
28
Q

Calcium and Bone disorders

Next step once primary hyperaparathyroidism is confirmed?

A

Perform US or sestambi scans to localize possible parathyroid adenoma causing hyperparathyroidism

29
Q

Calcium and Bone disorders

What is a treatment option for paitents with patients with primary hyperparathyroidism who are not surgical candidates for surgical parathyroidectomy?

A

Cinacalet

30
Q

Calcium and Bone Disorders

What are some causes of hypercalcemia with decreased PTH levels? (7)

A
  1. Immoblization
  2. Excess Vitamin D
  3. Excess Vitamin A
  4. Granuloamatous disease (Sarcoid/TB)
  5. Thyrotoxicosis
  6. Milk Alkalli syndrome
  7. Malignancy
31
Q

Calcium and Bone Disorders

What are the mechanisms of hypercalcemia of malignancy (3)

A
  1. Osteolytic bone lesions
  2. PTHrP production
  3. Extra-renal 1-alpha-hydroxylase production to make 1,25-OH-Vit D (Lymphoma)
32
Q

Bone and Calcium Disorders

Describe Milk-Alkali syndrome features (3)

What causes Milk-Alkali syndrome

A

Milk-Alkali syndrome is characterized by hypercalcemia, renal insufficiency, and metabolic alkalosis (alkali).

Caused by excessive ingestion of calcium carbonate.

33
Q

Calcium and Bone Disorders

When should patients with hypercalcemia from primary hyperparathyroidism have surgical parathyroidectomy?

A

When symptomatic from hyperparathyroidism.

Symptoms can include low bone desensity, kidney stones, CKD

34
Q

Calcium and Bone Disorders

What are some symptoms of hypocalcemia?

A
  1. Can have nonspecific symptoms like weakness, anxiety, depression
  2. Oral Parethesias
  3. Tetany
  4. Chvostek sign (spasm of the facial nerve when tapped)
  5. Trousseau sign (carpopedal spasm elicited by inflation of the blood pressure cuff above systolic pressure)
  6. Prolonged QT on EKG
  7. Bronchospasm
35
Q

Calcium and Bone Disorders

Severe Hypocalcemia can cause ________. ________ is a metabolic derangement that exacerbates hypocalcemic ________. ____ is a metabolic derangement that is protective agianst ________.

A

Severe hypocalcemia can result in seizures. Alkalosis is a metabolic derangement that can exacerbate hypocalcemic seizures. Acidosis is a metabolic derangement that is protective against hypolcemic seizures.

36
Q

Calcium and Bone Disorders

Describe hungry bone syndrome pathogenesis and when it is seen?

A

Hungry bone syndrome is seen in patients after parathyroidectomy. *PTH causes a net efflux of calcium from bones. Acute withdrawal of PTH causes a net influx of calcium onto bone. *

Risk factors for hungry bone syndrome include moderate to severe hyperparathyroidism before surgery with evidence of high bone turnover (elevated ALK-P).

PTH levels are usually normal but can be elevated. Phosphate and magnesium are also resorbed onto bone with calcium resulting in hypomagnesemia, hypophosphatemia, and hypocalcemia.

37
Q

Calcium and Bone Disorders

What electrolyte deficiency can worsen hypocalcemia? What types of patients is severe deficiency of this electrolyte seen in?

A

Severe hypomagnesemia can worsen hypocalcemia. Seen in alcoholics and patients with bowel disease (prevents absorption of magnesium)

38
Q

Calcium and Bone Disorders

Describe how celiac disease can result in hypocalcemia?

A

Uncontrolled celiac disease results in decreased gastrointestinal vitamin D absorption and subsequent vitamin D deficiency.

This leads to hypocalcemia (and hypophophastemia) and causes PTH to rise.

Increased PTH leads to normal calcium levels, low phosphorous, high PTH, and elevated Alkaline phosphatase (from increased bone turnover).

39
Q

Calcium and Bone Disorders

What is osteomalacia? How does it present in adults? What is a common cause of osteomalacia?

A

Osteomalacia is undermineralized bone. In adults, it presents with signs of bone pain. Commonly caused by vitamin D deficiency.

40
Q

Calcium and bone disorders

Lab finding in Osteomalacia (2)?

A

Hypocalcemia

Elevated alkaline phosphatase

41
Q

Calcium and Bone Disorders

MEN genetics?

A

All are autosomal dominant with varying expression.

42
Q

Calcium and Bone Disorders

Most common pituitary tumor and pancreatic tumor in MEN1?

A

Pancreatic tumor - Gastrinoma (causes PUD). Other pancreatic tumors include glucagonoma, insulinoma, VIPoma

Pituitary tumor - Prolactinoma

43
Q

Calcium and Bone Disorders

Symptoms of glucononoma? (3)

A
  1. Mild hyperglycemia
  2. Glossitis with a beefy red tongue
  3. Migratory necrolytic erythema - blistering erythemaatous rash found in the groin region
44
Q

Calcium and Bone Disorder

Key lab finding in medullary thyroid cancer?

A

High calcitonin levels

45
Q

General Principals

How does the hypothalamus control the anterior pituitary and the posterior pituitary?

A

Hypothalamus exerts control over the posterior pitutiary by direct nerve stimulation. Hypothalamus exerts control over the anterior pitutiary by releasing hormones.