Renal

Question 1

Excretion rate of x

Answer 1

Volume urine x Urine concentration of x

Question 2

Reabsorption rate of x

Answer 2

filtered - excreted

Question 3

filtered rate

Answer 3

GFR x Plasma concentration of x

Question 4

Secretion rate

Answer 4

Excreted - filtered.

Question 5

FeNa

Answer 5

Na excreted / Na filtered

= Pcr x Una / Ucr x Pna.

Question 6

Distal renal tubular acidosis

Answer 6

Type 1
Urine pH ABOVE 5.5
Defect of alpha intercalated cells to secrete H+ and to generate HCO3- for absorption.

–> metabolic acidosis and hypoklemia

–> increased risk for calcium phosphate stones due to increased urine pH/alkalinity.

Causes: amphotericin B, analgesic nephropatiy. Conginital obstruction of urinary tract.

Question 7

Proximal renal tubular acidosis

Answer 7

type 2.
Urine pH BELOW 5.5.
Defect in the Proximal conv. tubule resorption of HCO3-

Increased excretion of HCO3- and metabolic acidosis and hypokalemia
Increased risk for hypophosphatemic rickets.

Question 8

Hyperkalemic renal tubular acidosis

Answer 8

Type 4
Urine pH BELOW 5.5

Hypoaldosteronism, hyperkalemia, decreased NH4 excretion.

Caused by decreased aldosterone or aldosterone resistance.

Question 9

Fanconi syndrome

Answer 9

General resorption defect.

Increased excretion of amino acids, glucose, HCO3, and PO4.

Rsults in:
Metabolic proximal renal tubular acidosis

Causes:
Wilson disease, Ischemia, multiple myeloma, lead poisoning.

Question 10

Order of renal tubular defect syndromes

Answer 10

Fanconi-first, Barter, Gitelman, Liddle

Question 11

Bartter syndrome

Answer 11

Mutation in the Na/K/2Cl transporter in the thick ascending loop.

Similar to chronic loop diuretic use.

Hypokalemia
Hypochloremia
Metabolic alkalosis
HypercalciUria.

Volume depletion and increased plasma renin.

Question 12

Gitelman syndrome

Answer 12

Resorptive defect of NaCl in distal convoluted tubuel.
Like using chronic thiazide diuretics.

Hypokalemia, hypomagnesemia, metabolic alkalosis, hypocalciuria, hypercalcemia.

Question 13

Liddle syndrome

Answer 13

Gain of function mutation, increasing Na resorption in collecting tubule.

Hypertension, hypokalemia,
Metabolic alkalosis

Presents like hyperaldosteronism but aldosterone levels are extremely low.

Autosomal Dominant inheritance. Liddle dominant.

Question 14

Sydrome of Apparent Mineralocorticoid Excess

Answer 14

cortisol actin the SAME as aldosterone.

Deficiency of 11beta hydroxysteroid dehydrogenase, which normally inactivates cortisol to cortisone in kidneys.

Patients APPEAR to have MC excess, but actually have very low alkdosterone, and all of the effects are due to cortisol.

liquorice contains a chemical that inhibits it and can temporarily cause this syndrome.

aka hereditary 11-beta hydroxysteroid dehydrogenase defeciency.