Calcium/Phosphate

Question 0

Late neonatal hypocalcemia etiology

Answer 0

High phosphate diet
Hypoparathyroidism
Low Mg

Question 1

Early neonatal hypocalcemia etiology

Answer 1

Preterm decreased PTH secretion
Asphyxia
IDM (mom loses Mg so baby low Mg)
Low Mg (decreased PTH secretion/action)

Question 2

Childhood hypocalcemia etiology

Answer 2

Calcium malabsorption
Renal/liver dz (poor Vit D activation)
Meds (calcitonin, bisphosphonates)
Ca-sensing receptor defect (PTH can’t sense low Ca)

Question 3

Hypocalcemia symptoms

Answer 3

Seizures
Numbness
Chvostek sign
Trousseau sign
Laryngospasm, bronchospasm 
Prolonged QT

Question 4

Hypocalcemia work-up

Answer 4

Low PTH = hypoparathyroid
High PTH = Vit D deficiency, pseudohypoparathyroid

Check for low Mg
Check renal, liver function

Question 5

Calcium

Answer 5

Stored in bone, bound to albumin

Only free ion is active

Question 6

PTH

Answer 6

Increases Ca&raquo_space; bone turnover
Increases Ca&raquo_space; renal resorption
Decreases Phos&raquo_space; renal excretion
Increases Vit D&raquo_space; renal activation

Question 7

Vit D

Answer 7

Activated by liver then kidney

Increases Ca&raquo_space; renal resorption
Increases Ca&raquo_space; intestinal absorption
Increases Phos&raquo_space; intestinal absorption

Question 8

Calcitonin

Answer 8

made by thyroid C cells

Decreases Ca&raquo_space; bone resorption
Decreases Phos&raquo_space; bone resorption