Renal Tubular Acidosis Flashcards
1
Q
What is renal tubular acidosis?
A
Metabolic acidosis due to pathology in the tubules of the kidneys which normally balance hydrogen and bicarb ions between the blood and urine to maintain pH
2
Q
What are the 3 main types of RTA?
A
1 - due to distal tubule not being able to excrete hydrogen ions: high urinary pH and low serum K+
2 - due to proximal tubule being unable to reabsorb bicarb: high urinary pH and low serum K+
4 - due to low aldosterone or impaired aldosterone: low urinary pH and high serum K+
3
Q
What happens with RTA Type 1?
A
- High urinary pH
- Metabolic acidosis due to retained H+ ions
- Hypokalaemia
4
Q
What causes RTA type 1?
A
- Genetic
- SLE
- Sjogrens
- PBC
- Hyperthyroidism
5
Q
How does RTA T1 present?
A
- Failure to thrive in children
- Recurrent UTIs
- Bone disease
- Muscle weakness
6
Q
How is RTA T1 managed?
A
- Oral bicarbonate
7
Q
What happens with RTA T2?
A
- High urinary pH
- Metabolic acidosis due to inadequate bicarb
- Hypokalaemia due to loss of urinary K+
8
Q
What causes RTA T2?
A
- Inherited
- Multiple myeloma
9
Q
How is RTA T2 managed?
A
- Oral bicarbonate
10
Q
What is the pathophysiology of RTA T4?
A
- Reduced aldosterone meaning insufficient potassium and hydrogen ion excretion
- Urine becomes acidotic as ammonia production becomes suppressed
- Results in metabolic acidosis, hyperkalaemia and low urinary pH
11
Q
What causes RTA T4?
A
- Adrenal insufficiency
- Diabetic nephropathy
- Medications including ACE, spirinolactone
12
Q
How is RTA T4 managed?
A
- Treat cause
- Fludrocortisone may be used
- Oral bicarb/hyperkalaemia treatment may be needed
