Polycystic kidney disease, autosomal recessive (ARPKD)

Introduction

Autosomal recessive polycystic kidney disease (ARPKD) is a rare inherited childhood condition, where the development of the kidneys and liver is abnormal. Over time, either one of these organs may fail.

The condition often causes serious problems soon after birth, although less severe cases may not become obvious until a child is older.

ARPKD can cause a wide range of problems, including:

  • underdeveloped lungs, which can cause severe breathing difficulties soon after birth
  • high blood pressure (hypertension)
  • excessivepeeing and thirst
  • problems with blood flow through the liver, which can lead to serious internal bleeding
  • a progressive loss of kidney function, known as chronic kidney disease (CKD)

When these problems develop, and howsevere they are, can vary considerably even between family members with the condition.

It's estimated that around1 in 20,000 babies is born with the condition. Both boys and girls are affected equally.

What causes ARPKD?

ARPKD is caused by a genetic fault that disrupts normal development of the kidneys and liver.

In particular, the growth and development of the small tubes that make up the kidneys is affected, causing bulges and cysts (fluid-filled sacs) to develop within them.

Over time, the cysts cause the kidneys to become enlarged and scarred (fibrosis), resulting in the deterioration of overall kidney function.

Similar problems also affect the small tubes (bile ducts) that allow bile (a digestive fluid) to flow out of the liver. The bile ducts may develop abnormally and cysts may grow inside them. The liver can also become scarred over time.

ARPKD is caused by a genetic alteration in the gene PKHD1, which in most cases is passed on to a child by their parents. If bothparents carry a faulty version of this gene, there's a one in four (25%) chance of each child they have developing ARPKD.

The way ARPKD is inherited is differentfrom a more common type of kidney disease called autosomal dominant polycystic kidney disease (ADPKD) , which usually doesn't cause significantly reduced kidney function until adulthood. ADPKD can be inherited if only one parent carries one of the genetic faults responsible for the condition.

More thanhalf of all children who survive the early stages of ARPKD will eventually experience kidney failure by the time they're 15 to 20 years old.

If kidney failure does occur, there are two main treatment options:

  • dialysis where a machine is used to replicate many functions of the kidney
  • kidney transplant where a healthy kidney is removed from a living or recently deceased donor and implanted into someone with kidney failure

However, with advances in treatments and a better understanding ofthe condition, increasing numbers of children with ARPKD are living well into adulthood.

Content supplied by the NHS Website

Medically Reviewed by a doctor on 30 Nov 2016