Chronic renal failure in infants

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1 Great Ormond Street Hospital for Children NHS Foundation Trust: Information for Families Chronic renal failure in infants This information sheet explains chronic renal failure in infants under two years old, which is often caused by different things to chronic renal failure in older children. Each year around 20 children in the UK are born who will require dialysis in the first two years, and some of them will need it from when they are born. This information sheet also explains the options for treatment and what you can expect when your child comes to Great Ormond Street Children s Hospital for assessment and treatment. Kidneys Ureters Bladder Sphincter Urethra How does the urinary system work? The urinary system consists of the kidneys, the bladder and ureters. The kidneys filter the blood to remove waste products and form urine. The urine flows from the kidneys down through the ureters to the bladder. What is chronic renal failure? Chronic renal failure (CRF) is a term used to describe when the kidneys are not working as well as they should. The term implies that both kidneys are affected. This is because one normal kidney is enough to maintain normal kidney function throughout life. When both kidneys are damaged, they cannot keep up with the work that is asked of them, so that they may slowly fail over the years. When their function becomes very poor, terms other than CRF are used, like end-stage renal failure (ESRF). This term is not a very good one as it implies that there is nothing more that can be done, but in fact it means that there is a need for dialysis or transplantation to maintain good health. Dialysis and transplantation are often called renal replacement therapy (RRT). Sheet 1 of 5 Ref: 2014F0771 GOSH NHS Foundation Trust September 2014

2 How is chronic renal failure different in infants? The main differences are when chronic renal failure is diagnosed and its cause. Problems with the kidneys or their plumbing can be diagnosed before birth, which can lead to many families having months of anxiety before their baby is born. Around half of affected infants are diagnosed before birth although some of these may be missed if the mother does not have a scan during the last part of pregnancy. Sometimes it is possible to predict poor kidney function if the amount of fluid around the baby in the womb (amniotic fluid) is very low. This can be caused by a genetic condition, so genetic counselling should be offered to assess the chance of the same thing happening in future pregnancies. In some cases, the kidney problems may be linked to a blockage stopping urine draining from the bladder. In these cases, it may be possible to carry out surgery to relieve the blockage while the baby is still in the womb. However, there is no guarantee that this will stop the kidney failure. The important thing to remember is that one affected kidney does not necessarily mean kidney failure as the other kidney can continue to work well throughout life. What can cause chronic renal failure in infants? The most common diagnosis is renal dysplasia, which means that the kidney tissue has not formed normally. Other causes might be a blockage affecting urine drainage. This most often affects boys with a condition called posterior urethral valves (PUV). More information about this is in our Posterior urethral valves leaflet. The next most common cause is congenital nephrotic syndrome, where the kidneys leak protein so that the baby becomes swollen. For more information about congenital nephrotic syndrome, please see our leaflet. Finally, there are other causes affecting small numbers of children. These include kidney damage due to problems that happen during birth and some inherited kidney disorders that cause cysts to form in the kidney tissue. How can chronic renal failure in infants be treated? There are many factors that influence the treatments available and the nephrologists (doctors specialising in kidney disorders) will discuss these with you. The main options are palliative and supportive care or intensive treatment with renal replacement therapy (RRT). More information about each of these options follows. Sheet 2 of 5 Ref: 2014F0771 GOSH NHS Foundation Trust September 2014

3 Palliative and support care There may be circumstances when the family together with the medical and nursing team feel that the best option is palliative or supportive care to avoid any further pain or suffering for the infant. This involves making the infant comfortable without carrying out any intensive, invasive or painful procedures. This is more often the case when the infant has other conditions causing severe medical problems. In our experience, infants with severe kidney failure receiving palliative care do not survive longer than a year after birth. Families will be supported during this time both at GOSH and in their local area. Intensive treatment with renal replacement therapy (RRT) The aim of intensive treatment with renal replacement therapy (RRT) is to enable an infant to grow as much as possible so that he or she can receive a kidney transplant as soon as possible. This involves dialysis and diet therapy, leading to a kidney transplant. This is always an intensive process and a great deal of effort is needed from both the medical team and family. It will involve frequent hospital visits and close monitoring at home, with a detailed diet to follow and medicines to take. This can be a difficult time for families and they will be supported by GOSH and the local team. More detailed information about intensive treatment and RRT follows later in this information sheet. Deciding which option to take The main difficulty is that it is impossible to predict whether the infant s kidney function will continue to get worse or may have a period of improvement. The level of kidney function in infants with normal kidneys often improves during the first year of life and the same can happen in infants with chronic renal failure. Another reason for uncertainty is that many infants with chronic renal failure cannot concentrate their urine. This means that they lose large amounts of water and minerals daily so can manage for many months without dialysis, although growth and development is likely to be affected. You can discuss your options as frequently as you need with various members of the team. It is not impossible to change and switch to the other option, although this may have long-term effects on your infant s growth and development. Our aim is to give you as much advice and information as possible to help you understand the medical aspects of your child s care. We will support you throughout this difficult time so that the right form of care is offered to your child and that you can feel that the right choice was made for your child when you look back years later. Sheet 3 of 5 Ref: 2014F0771 GOSH NHS Foundation Trust September 2014

4 What does intensive treatment involve? There are various parts to intensive treatment all of which are vital to encourage your infant s growth and development until ready for transplant. Dialysis There are two types of dialysis: peritoneal dialysis and haemodialysis. In both types, the principal is the same: a cleaning fluid (called dialysate) is used to take the impurities, salt and water away from the blood. The impurities pass from the blood into the cleaning fluid, which then takes them away. There has to be a barrier between the blood and the cleaning fluid for this to happen. In haemodialysis, the barrier is the filter in the dialysis machine that the blood passes through and in peritoneal dialysis, the barrier is the layer of cells that lines the abdomen and covers the guts (the peritoneum). Peritoneal dialysis Overnight peritoneal dialysis (continuous cycling peritoneal dialysis or CCPD) is the preferred choice for infants with chronic renal failure. A machine is used to push fluid in and out of the abdomen. This dialysis takes place during the night while your child is asleep. The machine is about the size of a suitcase and is transportable to other houses if necessary. We usually prescribe 12 to 14 hours of dialysis to remove the large fluid volume of the infant s diet. The catheter may need to be replaced or other complications, such as peritonitis, can happen, but the risks are far less than with haemodialysis. Haemodialysis In our experience, haemodialysis is less suitable for very young children but not impossible. In this type of dialysis, there needs to be access to the blood vessels so that blood can be taken out of the body, passed through a filter to clean it and then returned to the body. In young children, access is usually through a catheter placed into the blood vessels in the neck. Catheters can easily become infected and may need to be replaced, sometimes damaging the blood vessel so that it cannot be used again. The haemodialysis machine needs to be primed with blood, and due to the small volume of blood in infants, donated blood is usually used. This means that, in effect, infants receive a blood transfusion each session, which can lead to problems with antibodies. This increases the difficulties of finding a future kidney transplant to match. Monitoring Intensive treatment involves very close monitoring of the infant to make sure that the best levels of growth and development are possible. The success of dialysis is measured regularly, often every week, and altered if needed. Your infant s diet will also be checked every week to make sure that he or she is receiving enough calories, and also changed if needed. Medicines needed to prevent long-term problems such as bone disease will also be monitored closely. Sheet 4 of 5 Ref: 2014F0771 GOSH NHS Foundation Trust September 2014

5 Diet It is rare for an infant with chronic renal failure to get enough goodness from his or her diet to ensure the best growth and development possible. Many infants have feeding problems, and some have gastro-oesophageal reflux or vomiting severe enough to need an operation to tighten the top of the stomach (Nissens fundoplication). For more information about this, please see our leaflet. A highcalorie and high-protein diet is needed and the majority of children also need supplements of minerals too. This is more likely in infants with structural kidney problems who lose minerals easily. Many children may not be able to feed adequately by mouth so need to be tubefed. This can either be through a nasogastric tube, which is passed through the nostril and down the food pipe into the stomach, or through a gastrostomy, which is passed through the skin directly into the stomach. For more information about these, please see our leaflets. Notes What is the outlook for infants with chronic renal failure? Adequate growth and development is the primary aim of intensive treatment. A closely monitored diet makes all the difference to the child s eventual height and weight, and many catch up once their diet is monitored closely and includes nutritional supplements. However, if a child does not achieve adequate growth, growth hormone treatment is a possibility if diet alone does not help as the child gets older. In our experience, few children have developmental problems after chronic renal failure, so most can attend mainstream school successfully. A successful kidney transplant is best possible outcome of intensive treatment. There seems to be little difference in success rates between transplants in infants and older children if the kidney is donated from a parent, although the chances of success are slightly lower with a deceased donor kidney. In our experience, there is no reason to hold off from a kidney transplant until the child is of a certain age or size, but it is preferable to be sure that all the immunisations are complete so it is rare to go ahead before 18 months of age. Compiled by Nephrology department in collaboration with the Child and Family Information Group. Great Ormond Street Hospital for Children NHS Foundation Trust, Great Ormond Street, London WC1N 3JH Sheet 5 of 5 Ref: 2014F0771 GOSH NHS Foundation Trust September 2014