Autosomal Recessive Polycystic Kidney Disease

Paediatric cystic renal disease with an autosomal recessive inheritance pattern

Aetiology

  • Affects young children
  • Several subtypes all occuring in childhood - perinatal, neonatal, infantile and juvenile
  • The abnormal gene is PKHD-1 which codes for fibrocystin
    • Found on chromosome 6

Pathophysiology

  • The early forms are usually fatal
  • Infantile and juvenile sufferers may survive but often go on to develop liver disease - cysts and congenital hepatic fibrosis
  • The kidneys are usually of normal size and still have a smooth outside
  • Renal involvement is bilateral and symmetrical
  • Urinary tract is generally normal
  • Histologically cysts are seen as appearing from the collecting duct system
  • Slow decline in GFR - less than 1/3 reach dialysis

Clinical presentation

  • Presentation varies and depends on the renal/liver lesions
  • Kidneys always palpable
  • Hypertension
  • Recurrent UTIs

Investigations

  • Imaging - USS, MRI

Management

  • Largely supportive
  • Dialysis and transplantation may be offered

Prognosis

  • 30-50% of children with ARPKD are severely affected
  • Infants who survive the neonatal period have a mortality rate of 9-24% in the first year of life
  • Children who survive the first year of life have a relatively good prognosis, with a survival probability of 80% beyond 15 years