hypoparathyroidism, cushing's

Question 1

What is the pathophysiology of hypoparathyroidism?

Answer 1

Insufficient parathyroid hormone (PTH) production leading to decreased blood calcium levels.

Question 2

How does negative feedback regulation work in the parathyroid glands?

Answer 2

Parathyroid glands produce PTH when calcium is low; PTH mobilizes calcium; when calcium rises, hormone production stops.

Question 3

What happens when parathyroid function is impaired?

Answer 3

Decreased PTH → decreased calcium levels in the blood.

Question 4

What are the main causes of hypoparathyroidism?

Answer 4

1. Removal or damage to parathyroid glands2. Autoimmune destruction of parathyroid3. Low magnesium (needed for PTH secretion).

Question 5

How does low magnesium affect hypoparathyroidism?

Answer 5

Magnesium is required for PTH secretion; low Mg impairs PTH release, worsening hypocalcemia.

Question 6

What are the clinical manifestations of hypoparathyroidism related to low calcium?

Answer 6

Hair dryness/loss, nail ridges/breakage, dry skin, bone loss, tingling in extremities, visual changes, muscle cramps, seizures, fatigue, positive Chvostek’s sign.

Question 7

What does a positive Chvostek’s sign indicate?

Answer 7

Neuromuscular irritability due to hypocalcemia.

Question 8

How is hypoparathyroidism diagnosed?

Answer 8

Based on medical/surgical history, physical examination, and lab tests.

Question 9

What might be observed during a physical exam for hypoparathyroidism?

Answer 9

Brittle nails, dry skin, and other visible calcium deficiency signs.

Question 10

What lab findings are seen in hypoparathyroidism?

Answer 10

Low PTH, low calcium, high phosphorus, low or normal magnesium, and low urinary calcium.

Question 11

What does low magnesium in hypoparathyroidism suggest?

Answer 11

That magnesium deficiency may be the cause of the disorder or contributing to symptoms.

Question 12

What are the treatments for hypoparathyroidism?

Answer 12

Calcium supplementation (carbonate or citrate), Vitamin D (enhances calcium absorption), Calcitriol, and recombinant/synthetic parathyroid hormone.

Question 13

What is the role of Vitamin D in hypoparathyroidism treatment?

Answer 13

Enhances calcium absorption from the GI tract.

Question 14

What is the pathophysiology of Cushing Syndrome?

Answer 14

Excess glucocorticoid (cortisol) secretion from the adrenal cortex affecting metabolism, stress response, and immune/inflammatory function.

Question 15

What are the four major causes of Cushing Syndrome?

Answer 15

1. Long-term corticosteroid use (e.g., prednisone)2. Pituitary tumors → excess ACTH3. Adrenal tumors → excess cortisol4. Ectopic ACTH/CRH production (e.g., small cell lung carcinoma).

Question 16

What happens when corticosteroids like prednisone are taken long-term?

Answer 16

Exogenous Cushing’s develops, leading to moon face, trunk obesity, and buffalo hump.

Question 17

What are the metabolic alterations in Cushing Syndrome?

Answer 17

Excess circulating glucose, glucose intolerance, suppressed immune/inflammatory response, behavioral changes, and impaired stress response.

Question 18

What is the typical body appearance in Cushing Syndrome?

Answer 18

Truncal obesity, moon face, and buffalo hump.

Question 19

Why do patients with Cushing Syndrome have glucose intolerance?

Answer 19

Excess cortisol promotes gluconeogenesis and decreases insulin sensitivity.

Question 20

Why is inflammation and immunity suppressed in Cushing Syndrome?

Answer 20

Cortisol suppresses immune and inflammatory responses, making patients more prone to infections.

Question 21

What behavioral changes occur in Cushing Syndrome?

Answer 21

Mood swings, irritability, insomnia, and sometimes depression.

Question 22

What happens to the stress response in Cushing Syndrome?

Answer 22

It becomes impaired; the body remains in a constant “fight or flight” state.

Question 23

How is Cushing Syndrome diagnosed?

Answer 23

Elevated cortisol in 24-hour urine, low-dose dexamethasone suppression test (no suppression = high cortisol), and imaging for tumors.

Question 24

How is a 24-hour urine collection for cortisol performed?

Answer 24

Patient voids and discards first urine; collection starts after that and continues for 24 hours; urine is stored in a jug on ice or in a refrigerator.

Question 25

What is the purpose of the low-dose dexamethasone suppression test?

Answer 25

To check if cortisol levels remain high despite dexamethasone administration, confirming Cushing’s.

Question 26

What imaging studies are used for Cushing Syndrome?

Answer 26

CT or MRI to detect pituitary or adrenal tumors or ectopic ACTH sources.

Question 27

What is the treatment goal for Cushing Syndrome?

Answer 27

Remove or correct the cause of excess cortisol secretion.

Question 28

What is the treatment for medication-induced Cushing Syndrome?

Answer 28

Gradual tapering of corticosteroids (not abrupt to avoid adrenal crisis).

Question 29

How is Cushing Syndrome due to tumors treated?

Answer 29

Surgical removal of tumors, chemotherapy, or radiation therapy depending on location and type.