Kidney disorders

Question 1

Renal tubular acidosis

Answer 1

Is a metabolic acidosis due to an impaired acid secretion by the kidney. There is a hyperchloraemic metabolic acidosis with a normal anion gap. There are 4 types, type 3 is a combo of types 1 and 2.

Question 2

Type 1 (distal) RTA

Answer 2

… is the inability to excrete H+ and generate acidic urine in the DCT. Even in the states of metabolic acidosis.

Question 3

Type 1 causes…

Answer 3

Inherited as a primary disorder or with
autoimmune disorders (e.g. Sjogren's, SLE),
Hyperparathyroidism, analgesic nephropathy, renal transplant rejection, obstructive uropathy and chronic urinary tract infections.

Question 4

Type 1 features…

Answer 4

Hyperventilation, muscle weakness, cardiac arrhythmias (hypokalaemia)
and bone pain (due to rickets or osteomalacia)
•Renal calculi, recurrent UTI, renal failure
Alkaline urine leading to phosphate stone formation.

Question 5

Type 1 investigations….

Answer 5

•Hypokalaemia, hyperchloraemic metabolic acidosis
•Urinary pH is above 5.5, despite metabolic acidosis.
- hypercalciuria

Question 6

Type 1 Rx…

Answer 6

• Oral sodium bicarbonate or citrate,
• Long term potassium supplements are usually not required as alkali therapy prevents excessive urinary potassium loss
• Acute: correct hypokalaemia before acidosis.

Question 7

Type 2 renal tubular acidosis

Answer 7

is due to a bicarbonate leak: a defect in the HCO3- reabsorption in the