Patho. Chp. 8

Question 2

Calcium homeostasis

Answer 2

Controlled by negative feedback to keep serum calcium in a narrow range for normal body function.

Question 3

Normal serum calcium range

Answer 3

8.5–10.5 mg/dL.

Question 4

Why calcium is critical

Answer 4

Action potentials, muscle contraction, enzyme activity.

Question 5

Parathyroid glands location

Answer 5

Four glands on the posterior surface of the thyroid gland.

Question 6

Parathyroid hormone (PTH) main job

Answer 6

Raises blood calcium when calcium is low.

Question 7

Primary triggers for PTH release

Answer 7

Low blood calcium levels.

Question 8

Main PTH target organs

Answer 8

Bone and kidneys (and indirectly the intestine via vitamin D activation).

Question 9

PTH effect on bone

Answer 9

Mobilizes calcium from bone stores into the blood.

Question 10

PTH effect on kidneys

Answer 10

Increases renal reabsorption of calcium back into the blood.

Question 11

PTH indirect effect on intestines

Answer 11

Promotes intestinal calcium absorption through activated vitamin D (calcitriol).

Question 12

Negative feedback in PTH control

Answer 12

When blood calcium rises, PTH production decreases.

Question 13

Hypoparathyroidism definition

Answer 13

Low PTH secretion causing impaired ability to raise blood calcium.

Question 14

Most common cause of hypoparathyroidism

Answer 14

Damage to parathyroid glands during thyroid surgery or thyroid radiation.

Question 15

Other causes of hypoparathyroidism

Answer 15

Congenital disorders; autoimmune injury with autoantibodies.

Question 16

Core pathophysiology of hypoparathyroidism

Answer 16

Low PTH → reduced bone calcium mobilization + reduced renal calcium reabsorption + less calcitriol effect → hypocalcemia.

Question 17

Resulting electrolyte imbalance

Answer 17

Hypocalcemia.

Question 18

Hypocalcemia key effect

Answer 18

Enhanced neuromuscular irritability.

Question 19

Why hypoparathyroidism symptoms can be missed

Answer 19

Symptoms are general and overlap with hypocalcemia; labs are needed.

Question 20

Adult manifestations: hair

Answer 20

Hair dryness and loss.

Question 21

Adult manifestations: nails

Answer 21

Nail ridges and breakage.

Question 22

Adult manifestations: skin

Answer 22

Skin dryness.

Question 23

Adult manifestations: bone

Answer 23

Bone loss.

Question 24

Adult manifestations: neuro

Answer 24

Tingling in extremities (paresthesia), fatigue.

Question 25

Adult manifestations: muscle

Answer 25

Muscle cramps.

Question 26

Adult manifestations: severe neuro

Answer 26

Seizures.

Question 27

Adult manifestations: vision

Answer 27

Visual changes.

Question 28

Congenital hypoparathyroidism risk

Answer 28

Children are highly susceptible to neurologic effects of low calcium.

Question 29

Congenital hypoparathyroidism manifestations

Answer 29

Seizures, diminished growth, neurological deficits.

Question 30

Important history clue for hypoparathyroidism

Answer 30

History of thyroid surgery or thyroid radiation.

Question 31

Key labs for diagnosis

Answer 31

PTH, serum calcium, phosphorus, magnesium.

Question 32

Why phosphorus is checked

Answer 32

Helps identify the pattern of electrolyte imbalance related to low PTH.

Question 33

Why magnesium is checked

Answer 33

Magnesium abnormalities can contribute to PTH issues and calcium imbalance.

Question 34

Urinary calcium usefulness

Answer 34

Shows how effectively the kidneys are reabsorbing calcium.

Question 35

Goal of treatment

Answer 35

Maintain calcium at the lower end of normal and reduce hypocalcemia manifestations/complications.

Question 36

First-line long-term treatment

Answer 36

Oral calcium (carbonate or citrate) + vitamin D (calcitriol).

Question 37

Why calcitriol is used

Answer 37

Improves intestinal calcium absorption to support serum calcium.

Question 38

When recombinant PTH is used

Answer 38

When calcium and vitamin D supplementation cannot control the condition.

Question 39

Recombinant PTH dosing

Answer 39

Once-daily injection.

Question 40

Major safety concern with recombinant PTH

Answer 40

Potential bone cancer risk seen in animal studies; reserved for special cases.

Question 41

Chvostek sign (test tip)

Answer 41

Facial twitching with tapping the facial nerve—suggests hypocalcemia.

Question 42

Trousseau sign (test tip)

Answer 42

Carpal spasm with BP cuff inflation—suggests hypocalcemia.

Question 43

Priority nursing concern in severe hypocalcemia

Answer 43

Seizure risk and neuromuscular irritability.