Paediatric Nephrology - Chronic Kidney Failure

Question 1

CKD - aetiology

Answer 1

• Congenital anomalies of kidney and urinary tract
  
  • Can be standalone or associated with – turners, trisomy 21, Branchio-oto-renal, prune belly syndrome
  • 55%
• Hereditary conditions
  
  • Cystic kidney disease
  • Cystinosis
  • 17%
• Glomerulonephritis
  
  • 10%

Question 2

CKD - staging

Answer 2

• CKD2 60-89
• CKD3 30-59
  
  • CKD3a 45-59
  • CKD3b 30-44
• CKD4 15-29
• CKD5 (end stage renal disease)

Question 3

CKD - presentation

Answer 3

Symptoms variable depending on which function affected:

• Waste handling
  
  • Increased appetite
• Water handling
  
  • Polyuric or oliguric
• Salt balance
  
  • Hyponutramia which may affect growth, or hypernatraemia which may affect cardiac health
• Acid base control
  
  • Affects growth
• Endocrine
  
  • Anaemia, hypertension if oliguric, hypotensive if polyuric
• Bladder dysfunction

Question 4

UTI - aetiology

Answer 4

• Normally E-coli

Question 5

UTI - diagnosis

Answer 5

• Clinical signs plus
  
  • Bacterial culture from midstream urine
  • Any growth on suprapubic aspiration or catheter

Question 6

What are clinical findings for UTIs in:

• neonates
• pre verbal children
• verbal children

Answer 6

Question 7

UTI - investigations

Answer 7

• Mid-stream urine sample
• If acutely unwell, do not delay treatment
• Making the diagnosis
  
  • Urine dipstix
    
    • Leucocyte esterase activity, nitrates
  • Microscopy
    
    • Pyruria
    • Bacteruria
  • Culture – gold standard
    
    • >10⁵ colony forming units/ml

Question 8

How can UTI precipitate kidney injury?

Answer 8

• May cause kidney injury through vescico-ureteric reflux
  
  • Causing scarring

Question 9

Who with a UTI should have their kidneys investigated?

Answer 9

• Upper tract symptoms
• Younger
• Recurrent

Question 10

What investigations can be done to look at kidneys in UTI?

Answer 10

• USS
  
  • Structure
• DMSA (isotope scan)
  
  • Scarring/function
• Micturating cysto-urethrogram MAG 3 scan
  
  • Dynamic

Question 11

UTI - treatment

Answer 11

• Lower tract
  
  • 3 days oral antibiotics
• Upper tract/pyelonephritis
  
  • Antibiotics for 7-10 days
• Prevention
  
  • Fluids, hygiene, avoid constipation
• Manage voiding symptoms

Question 12

What factors affect progression of CKD?

Answer 12

• Late referral
• Hypertension
• Proteinuria
• High intake of protein, phosphate and salt
• Bone health
  
  • PTH
  • Phosphate
  • Vitamin D
• Acidosis
• Recurrent UTIs

Question 13

What factors affect normal BP in children?

Answer 13

• Sex
• Age
• Height

Question 14

What is hypertension in children defined as?

Answer 14

Hypertension is >= 95th percentile for parameters, borderline is >=90^th percentile

Question 15

CKD - management

Answer 15

Variable depending on which function altered:

• Waste handling
  
  • Reduce protein intake
• Water handling
  
  • Fluid restriction or free access
• Salt balance
  
  • Sodium restriction or supplementation
• Acid base control
  
  • Bicarbonate replacement
• Endocrine
  
  • Control BP with ACE inhibitors

Question 16

CKD - complications

Answer 16

• Metabolic bone disease
• Cardiovascular risk
  
  • Accelerated atherosclerosis

Question 17

How can CKD lead to metabolic bone disease?

Answer 17

• Kidneys wee out phosphate
  
  • High phosphate causes increase PTH
• Kidneys activate vitamin D3

Question 18

Metabolic bone disease - treatment principles

Answer 18

• Low phosphate diet
• Phosphate binders
• Active vitamin D
• Growth hormone – if ongoing poor growth