Renal Tubular Acidosis Flashcards
Explain
When there is metabolic acidosis due to pathology of tubules of kidney.
The tubules are usually responsible for balancing the hydrogen and bicarb ions to create a normal pH, if this doesn’t work in the renal tubules it is called renal tubular acidosis.
Types of RTA
1-4
Explain Type 1
Pathology of distal tubule so excretion of hydrogen ions does not work.
Causes of type 1
Genetic
SLE
Sjögren’s
CF of type 1
Failure to thrive in children
Hyperventilation
CKD
Osteomalacia
Ix findings of Type 1
Hypokalaemia
Metabolic acidosis
High urinary pH >6
Tx type 1
Oral bicarbonates
Explain Type 2
Pathology of the proximal tubule
This means that the proximal tubule is not able to reabsorb the bicarbonate anymore.
The excessive bicarb is excreted in the urine.
Main cause of Type 2
Fanconi’s syndrome
Ix findings of type 2
Hypokalaemia
Metabolic acidosis
High urinary pH
Tx type 2
Oral bicarb
What is type 3
A combo of type 1 and 2
Very rare
Explain Type 4
RTA due to reduced aldosterone
This is the most common cause of RTA
Causes of Type 4
Adrenal insufficiency
ACEi and spironolactone
SLE
Diabetes
HIV
Ix findings Type 4
Hyperkalaemia
High chloride
Metabolic acidosis
Low urinary pH
