CPRS Case 10: Renal Failure

Question 1

Recognise physiology of normal kidney functions and pathophysiology in kidney failure

Answer 1

See lecture

Question 2

Mechanism of fluid / electrolyte / acid-base homeostasis and excretion of metabolic waste by the kidneys

Answer 2

See lecture

Question 3

Difference between acute and chronic renal failure, and conditions that can lead to either

Answer 3

Acute:

• quick onset
• reversible
• pre-renal: Ischaemia
• intra-renal: GN, tubular necrosis
• post-renal: UTI

Chronic:

• gradual onset
• irreversible loss of nephrons
• Chronic glomerulonephritis
• hypertension
• DM
• long term medication (NSAIDs)

Question 4

Approach to investigate patient’s with abnormal renal function

Answer 4

1. Urinalysis
   - Protein
   - RBC
   - Glucose
2. Blood test
   - Electrolyte
   - Urea and Creatinine
   - Liver enzymes (ALT, Alkaline Phosphatase)
   - Haemoglobin
3. Ultrasonogram
   - Size of kidney

Question 5

***Common biochemical / haematological investigation results of patients with renal diseases

Answer 5

Chronic renal failure:

• Generalised oedema (salt and water retention)
• Metabolic acidosis (cannot excrete acidic products)
• Azotaemia / uraemia (cannot excrete metabolic end products of proteins)
• High concentration of other substances (phenols, phosphates, potassium)

***Kidney failure
Increase:
- Non-protein nitrogenous waste product
- K (calcium gluconate, beta agonist, insulin)
- H
- water
- Phosphate, sulphate (phosphate binder)
- phenols
Decrease:
- Na
- HCO3 (cannot synthesize)
- RBC (blood transfusion may worsen fluid overload)
- albumin
- Ca (arrhythmia, neuromuscular disease)

Water retention:

• reduced kidney function to excrete water and salt
• decrease in Na concentration (dilution effect)
• increased secretion of renin and angiotensin
• decrease in albumin

Increased potassium and phosphate:
- due to decreased GFR

Acidosis:

• acid accumulate in body fluid
• buffering power is used up —> Low bicarbonate level

Azotaemia:

• Increased urea, uric acid, creatinine
• concentration rise in proportion to degree of reduction —> assess CKD severity

Decreased albumin:

• loss in urine
• protein energy wasting

Anaemia:

• reduced erythropoietin production
• chronic problem because hormonal changes take time

Question 6

Psycho-social implications of chronic renal failure and of patients with chronic disease in general

Answer 6

1. Intense emotions to illness
2. Change of behaviour
3. Disruption to work, school (unemployment)
4. Disruption to family life (change in family role)

Question 7

Factors that determine health seeking behaviour and psychological reactions of patients towards chronic diseases

Answer 7

Factors that determine health seeking behaviour

• Gender
• Social support (migration)
• Financial
• Illness cognition (how common, how familiar with the symptoms)
• Illness danger (predictability of outcome, amount of threat)

Psychological reaction towards chronic diseases

• Fear
• Anxiety
• Depression

Default follow-up

• Financial consideration
• Dissatisfaction
• Patient’s belief
• Improvement in symptoms

Question 8

Impact of health economics involved in management of patients with chronic renal failure, and of patients with chronic diseases in general

Answer 8

• A lot of money spent on dialysis and renal transplant

- Disturbance to everyday life

Question 9

Ethical issues involved in renal replacement therapy

Answer 9

1. Organ trade
2. Familial pressure towards living-related transplantation
3. Appropriate allocation of available organ
4. Ways to increase organ donation