Autosomal recessive polycystic kidney disease (ARPKD) is characterised by the presence of enlarged kidneys with dilatation of the renal collecting ducts alongside liver involvement which is primarily that of fibrosis.
It is a rare condition with an incidence of 1:10000 to 1:40000. It's autosomal recessive inheritance means that there is a 1 in 4 risk to siblings of affected individuals. The responsible gene is located on the long arm of chromosome 6.
The disease is usually evident in the neonatal period. Severe renal disease causes oligohydramnios with enlarged, echogenic kidneys. This may lead to severe lung disease and a Potters-like syndrome.
Less severely affected children may have normal renal function early on in life but develop renal failure later on. End-stage renal failure develops before adulthood in a third of patients.
Liver involvement may also be severe with development of fibrosis, with hepatomegaly and portal hypertension. Liver failure can occur, requiring transplantation.