Renal Other

Question 1

What is renal tubular acidosis?

Answer 1

Metabolic acidosis due to pathology in the tubules of the kidney (responsible for balancing hydrogen + bicarbonate ions)

Question 2

What causes type 1 renal tubular acidosis?

Answer 2

Distal tubule unable to excrete hydrogen ions

Causes:

• genetic
• SLE
• Sjogrens
• primary biliary cirrhosis
• hyperthyroidism
• sickle cell
• Marfan’s

Question 3

How does type 1 renal tubular acidosis present?

Answer 3

Failure to thrive in children
Hyperventilation (compensation)
CKD
Osteomalacia

Question 4

What are the biochemical findings in type 1 renal tubular acidosis?

Answer 4

Hypokalaemia
Metabolic acidosis
High urinary pH (above 6)

Question 5

How is type 1 renal tubular acidosis treated?

Answer 5

Oral bicarbonate

Question 6

What causes type 4 renal tubular acidosis?

Answer 6

Reduced aldosterone:

• adrenal insufficiency
• ACE inhibitors
• spironolactone
• SLE
• diabetes
• HIV

Question 7

What are the biochemical findings in type 4 renal tubular acidosis?

Answer 7

Hyperkalaemia
High chloride
Metabolic acidosis
Low urinary pH

Question 8

How is type 4 renal tubular acidosis treated?

Answer 8

Fludrocortisone

Sodium bicarbonate + treatment of hyperkalaemia may also be required

Question 9

What causes acute interstitial nephritis?

Answer 9

Hypersensitivity reaction to:

• drugs (NSAIDs or antibiotics)
• infection

Question 10

What are the features of acute interstitial nephritis?

Answer 10

AKI + hypertension
May be features of hypersensitivity:
- rash
- fever 
- eosinophilia

Question 11

How is acute interstitial nephritis managed?

Answer 11

Treat underlying cause

Steroids to reduce inflammation

Question 12

What causes haemolytic uraemic syndrome (HUS)?

Answer 12

Shiga toxin, usually produced by E.coli 0157

Can also be produced by shigella

Question 13

What increases the risk of developing HUS following infection?

Answer 13

Use of antibiotics and anti-motility drugs e.g. loperamide

Question 14

What is the classic triad of HUS?

Answer 14

Haemolytic anaemia
AKI
Low platelets (thrombocytopenia)

Question 15

What are the clinical features of HUS?

Answer 15

Brief gastroenteritis with bloody diarrhoea
About 5 days later:
- reduced urine output
- haematuria or dark brown urine
- abdominal pain
- lethargy + irritability
- confusion
- hypertension
- bruising

Question 16

How is HUS managed?

Answer 16

Medical emergency –> supportive management

• antihypertensives
• blood transfusions
• dialysis

Question 17

What is rhabdomyolysis?

Answer 17

Breakdown of skeletal muscle cells releasing contents into the blood:

• myoglobin (–> myoglobinuria)
• potassium
• phosphate
• creatinine kinase

Question 18

What are the consequences of breakdown product release in rhabdomyolysis?

Answer 18

Potassium –> hyperkalaemia –> arrhythmias

Myoglobin is toxic to kidneys –> AKI

Question 19

What are the signs and symptoms of rhabdomyolysis?

Answer 19

Muscle aches and pains
Oedema
Fatigue
Confusion (esp in elderly)
Red-brown urine

Question 20

Which investigations help diagnose rhabdomyolysis?

Answer 20

CK will be in thousands
Red-brown urine –> positive for blood
U&Es for kidney injury + potassium
ECG essential

Question 21

What causes rhabdomyolysis?

Answer 21

Prolonged immobility
Extremely rigorous exercise
Crush injuries
Seizures

Question 22

How is rhabdomyolysis managed?

Answer 22

IV fluids mainstay of treatment
Treat hyperkalaemia
Consider:
- IV sodium bicarb to protect kidneys
- IV mannitol to increase GFR