I n t e r n a L medicine questions Bank

Rhabdomyolysis
Rhabdomyolysis will typically feature in the exam as a patient who has had a fall or prolonged epileptic seizure and is found to have acute renal failure on admission

Features

• 
  acute renal failure with disproportionately raised creatinine
  
• 
  elevated CK
  
• 
  myoglobinuria
  
• 
  hypocalcaemia (myoglobin binds calcium)
  
• 
  elevated phosphate (released from myocytes)
  

Causes

• 
  seizure
  
• 
  collapse/coma (e.g. elderly patients collapses at home, found 8 hours later)
  
• 
  ecstasy
  
• 
  crush injury
  
• 
  McArdle's syndrome
  
• 
  drugs: statins
  

Management

• 
  IV fluids to maintain good urine output
  
• 
  urinary alkalinization is sometimes used
  

1 5-Which one of the following drugs may be safely continued at the same dose in renal failure?

	A.	Tetracycline
	B.	Diclofenac
	C.	Warfarin
	D.	Nitrofurantoin
	E.	Lithium

Drugs in renal failure

Questions regarding which drugs to avoid in renal failure are common in the MRCP Drugs to avoid in renal failure

• 
  antibiotics: tetracycline, nitrofurantoin
  
• 
  NSAIDs
  
• 
  lithium
  

Drugs likely to accumulate in renal failure - need dose adjustment

• 
  most antibiotics including penicillins, cephalosporins, vancomycin, streptomycin
  
• 
  digoxin, atenolol
  
• 
  methotrexate
  
• 
  sulphonylureas
  
• 
  frusemide
  

Drugs relatively safe - use in normal dose

• 
  antibiotics: erythromycin, rifampicin
  
• 
  diazepam
  
• 
  warfarin
  

1 6-Each of the following is a risk factor for renal stone formation, except:

	A.	Renal tubular acidosis
	B.	Cadmium
	C.	Hyperparathyroidism
	D.	Dehydration
	E.	Cystinosis

Renal stones: risk factors

Risk factors

• 
  dehydration
  
• 
  hypercalciuria, hyperparathyroidism, hypercalcaemia
  
• 
  cystinuria
  
• 
  high dietary oxalate
  
• 
  renal tubular acidosis
  
• 
  medullary sponge kidney, polycystic kidney disease
  
• 
  beryllium or cadmium exposure
  

Risk factors for urate stones

• 
  gout
  
• 
  ileostomy: loss of bicarbonate and fluid results in acidic urine, causing the precipitation of uric acid
  

Drug causes

• 
  drugs that promote calcium stones: loop diuretics, steroids, acetazolamide, theophylline
  
• 
  thiazides can prevent calcium stones (increase distal tubular calcium resorption)
  

17. 
    Which one of the following causes of glomerulonephritis is associated with normal complement levels?
    

	A.	Post-streptococcal glomerulonephritis
	B.	Mesangiocapillary glomerulonephritis
	C.	Subacute bacterial endocarditis
	D.	Goodpasture's syndrome
	E.	Systemic lupus erythematous

Goodpasture's syndrome is rare condition associated with both pulmonary haemorrhage and rapidly progressive glomerulonephritis. It is caused by anti-glomerular basement membrane (anti-GBM) antibodies against type IV collagen. Complement levels are normal


Glomerulonephritis and low complement

Disorders associated with glomerulonephritis and low serum complement levels

• 
  post-streptococcal glomerulonephritis
  
• 
  subacute bacterial endocarditis
  
• 
  systemic lupus erythematous
  
• 
  mesangiocapillary glomerulonephritis
  

1 8-Autosomal dominant polycystic kidney disease type 1 is associated with a gene defect in:

		A.	Chromosome 4
		B.	Chromosome 8
		C.	Chromosome 12
		D.	Chromosome 16
		E.	Chromosome 20
ADPKD type 1 = chromosome 16 = 85% of cases

ADPKD
Autosomal dominant polycystic kidney disease (ADPKD) is the most common inherited cause of kidney disease, affecting 1 in 1,000 Caucasians. Two disease loci have been identified, PKD1 and PKD2, which code for polycystin-1 and polycystin-2 respectively

ADPKD type 1	ADPKD type 2
85% of cases	15% of cases
Chromosome 16	Chromosome 4
Presents with ESRF earlier

The screening investigation for relatives is abdominal ultrasound: Ultrasound diagnostic criteria (in patients with positive family history)

• 
  two cysts, unilateral or bilateral, if aged < 30 years
  
• 
  two cysts in both kidneys if aged 30-59 years
  
• 
  four cysts in both kidneys if aged > 60 years
  

1 9-A 27-year-old man is diagnosed with Goodpasture's syndrome. Which one of the following does not increase the likelihood of a pulmonary haemorrhage?

	A.		Smoking
	B.		Inhalation of hydrocarbons
		C.	Male gender
		D.	Dehydration
		E.	Lower respiratory tract infection

Dehydration may decrease the likelihood of a pulmonary haemorrhage. Pulmonary oedema is associated with an increased risk

Goodpasture's syndrome
Goodpasture's syndrome is rare condition associated with both pulmonary haemorrhage and rapidly progressive glomerulonephritis. It is caused by anti-glomerular basement membrane (anti-GBM) antibodies against type IV collagen. Goodpasture's syndrome is more common in men (sex ratio 2:1) and has a bimodal age distribution (peaks in 20-30 and 60-70 age bracket). It is associated with HLA DR2
Features

• 
  pulmonary haemorrhage
  
• 
  followed by rapidly progressive glomerulonephritis
  

Factors which increase likelihood of pulmonary haemorrhage

• 
  young males
  
• 
  smoking
  
• 
  lower respiratory tract infection
  
• 
  pulmonary oedema
  
• 
  inhalation of hydrocarbons
  

Investigations

• 
  renal biopsy: linear IgG deposits along basement membrane
  

• 
  plasma exchange
  
• 
  steroids
  
• 
  cyclophosphamide
  

2 0-A patient with type 1 diabetes mellitus is reviewed in the nephrology outpatient clinic. He is known to have stage 1 diabetic nephropathy. Which of the following best describes his degree of renal involvement?

	A.	Latent phase
	B.	Hyperfiltration
	C.	End-stage renal failure
	D.	Overt nephropathy
	E.	Microalbuminuria

For the purposes of the MRCP, increase in the glomerular filtration rate (GFR) is most characteristic of stage 1 diabetic nephropathy. It is however known that elevation of the GFR usually persists into stage 2

Diabetic nephropathy: stages

Diabetic nephropathy may be classified as occurring in five stages*:

Stage 1

• 
  hyperfiltration: increase in GFR
  
• 
  may be reversible
  

Stage 2 (silent or latent phase)

• 
  most patients do not develop microalbuminuria for 10 years
  
• 
  GFR remains elevated
  

• 
  microalbuminuria (albumin excretion of 30 - 300 mg/day, dipstick negative)
  

Stage 4 (overt nephropathy)

• 
  persistent proteinuria (albumin excretion > 300 mg/day, dipstick positive)
  
• 
  hypertension is present in most patients
  
• 
  histology shows diffuse glomerulosclerosis and focal glomerulosclerosis (Kimmelstiel-Wilson nodules)
  

Stage 5

• 
  end-stage renal disease, GFR typically < 10ml/min
  
• 
  renal replacement therapy needed
  

The timeline given here is for type 1 diabetics. Patients with type 2 diabetes mellitus (T2DM) progress through similar stages but in a different timescale - some T2DM patients may progress quickly to the later stages

21. 
    Alport's syndrome is due to a defect in:
    

A.	Type I collagen
B.	Type II collagen
C.	Type III collagen
D.	Type IV collagen
E.	Type V collagen

Alport's syndrome
Alport's syndrome is a hereditary condition, usually X-linked dominant but may be autosomal recessive or dominant. It is due to a defect in the gene which codes for type IV collagen resulting in an abnormal glomerular-basement membrane (GBM). The disease is more severe in males with females rarely developing renal failure
This may be caused by the presence of anti-GBM antibodies leading to a Goodpasture's syndrome like picture

Alport's syndrome usually presents in childhood. The following features may be seen:

• 
  microscopic haematuria
  
• 
  progressive renal failure
  
• 
  bilateral sensorineural deafness
  
• 
  retinitis pigmentosa
  
• 
  lenticonus: protrusion of the lens surface into the anterior chamber
  

2 2-Which one of the following may be useful in the prevention of calcium renal stones?

	A.	Pyridoxine
	B.	Allopurinol
	C.	Lithium
	D.	Ferrous sulphate
	E.	Thiazide diuretics