Potassium

Question 1

Causes of Hyperkalemia

Answer 1

o Due to impair cell entry to K
o Increase cell release of k
o Reduce urinary excretion of K

Question 2

Causes: Hypokalemia

Answer 2

o Intracellular shift of K
o Gastrointestinal losses of K
o Increase urinary excretion of K

Question 3

Difference between Gitelmans and bartter

Answer 3

• Gitelmans→ HYPOcalciuria (low level of calcium in the urine).
• Bartter syndrome→ HYPERcalciuria (HIGH level of calcium in the urine).

Question 4

Bartter’s Syndrome

Answer 4

Hypokalemia. Ascending limb of loop of henle. Age: prenatal infancy, early childhood. Biochem: serum mag decreased, urinary excretion of calcium increase or normal. Molecular diff: NA-K-2CL cotranporter, apical k Channel (ROMK) or basolateral Cl channel (ClCNKS)
Functional: premature birth, growth retardation

Question 5

Gitelman’s Syndrome

Answer 5

Distal tube, late childhood, serum mag decrease, urinary excretion of calcium reduced, Na-CL co transporter in the distal tubule, Function mild growth retardation.

Question 6

Hypokalemia lab

Answer 6

K+ <3.6 mEq/L

Question 7

Hypokalemia symptoms

Answer 7

Muscle weakness, cramp, tetany, polyuria, polydipsia

Question 8

Hypokalemia signs

Answer 8

Decreased motor strength, orthostatic, hypotension, ileus, ECG changes: flattening of T waves, U wave become obvious