One sunny day, Thomas the Tank Engine was moving along his shiny metal tracks returning to his hometown after a busy weekend in Scotland. Over the past year Thomas had noticed he was not able to move as fast as his best friends Percy and Toby. He felt more tired and his usual bright blue appearance had now turned dull and silvery. He also noticed his appetite for engine fuel had decreased and thought this was very unlike him. He had even noticed some pain in his huge black wheels as they scraped along the tracks.
As he docked his train into the station sounding his horn, which bellowed through the air causing the nearby blackbirds to leave their nest. As Thomas’ wheels screeched to a halt, his friend Terry came out of the station office to check how Thomas was doing from his difficult trip to the North. Terry was Thomas’s personal mechanic he was dressed in a bright green overall carrying his box of tools in one hand and a towel in the other. As he approached Thomas he exclaimed, “Thomas you don’t look too good? Has something happened on your journey?” Thomas explained, “No Terry, I just have not been feeling the same since earlier this year but I did not think too much of it.”
Terry walked down the platform to check all the carriages belonging to Thomas, and he too noticed the dullness of the train. He ran back to the first carriage and said, “Thomas I’m going to run a diagnostic test on you to see what is wrong so we can get you back to your shiny bright blue self quickly.” Thomas smiled at Terry and nodded. Terry brought out a hand-held electronic machine from his tool kit and he moved to Thomas’s engine. The plugged the machine into the train and took a recording. After a few minutes he unplugged the small machine and went back to Thomas.
“Thomas, your reading says you have engine failure.” Thomas was worried he did not know what engine failure was but it did not sound good he replied, “Terry I do not understand what engine failure means. Is it bad? What will happen now?” Terry looked reassuringly at Thomas and said, “You must have many questions for me Thomas, but firstly I want to ease your worries. Engine failure is something that happens in trains, but in people like me Thomas, we call it renal failure. There are two kidneys in the body both responsible for removing waste products and producing urine, which is passed out of the body when people go to the toilet. As blood travels through the kidney glomeruli – these are small pockets in the kidney- waste products pass through them to make urine, which is stored in the bladder till it leaves the body. This is like your engine, which is responsible for getting rid of waste engine gases through the exhaust pipes.”
Thomas listened intently and said, “So Terry, my engine is not effective at getting rid of waste substances?” Terry replied, “Exactly Thomas, similar to renal failure when both kidneys are damaged from many different causes including: inherited conditions like polycystic kidney disease, infections, autoimmune conditions like systemic lupus or diabetes, medicines or even kidney stones that cause blocks. However in most young children the cause of renal failure is due to genetic illnesses or kidneys that are not like usual kidneys from birth, thereby causing poor kidney function. This damage means they are unable to filter the waste in the body. Therefore Thomas both your engines could be faulty, which means that you are not removing the waste gas you are producing from your travels.”
Thomas asked, “How have you measured this Terry?” Terry said, “Well this machine allowed me to look at the rate at which your engine is able to remove the gas from engine pipes. It is similar to a glomerular filtration rate (GFR), which allows people to calculate the rate at which these small pockets in the kidney are able to filter out waste products from the blood. This allows us to determine the extent of damage to the kidney; in chronic renal failure it is lower than it should be. We can also look at another marker known as creatinine in the blood to determine kidney function.”
Thomas started to look worried, “Does this mean my engine will eventually not work anymore?” Terry looked at Thomas and spoke calmly, “ In some children the kidneys will remain stable for many years or get better, however in other children the kidneys may worsen as they get tired more quickly and cannot deal with the extra effort of filtration. So Thomas your engine may stay this way or get worse, but Thomas do not worry. Many people can go through different types of failure for other body parts including the kidneys and there are different ways to help keep your body working and to keep you happy and healthy. You are not alone, there are other people out there who understand what you are going through and are always there to help.” Thomas smiled, he was gleeful at knowing he was not alone, there were other trains that experienced failure of their engines too and even humans like Terry could experience their own type of engine failure in their kidneys. He was happy at knowing there would always be support out there for him if he ever needed it.
“Terry what is the next step now?” Thomas inquired. “Well Thomas in children with Chronic renal failure we have a few options, we can monitor their kidney function whilst it is stable and pay close attention to their blood pressure which may need to be treated with medicines if it is too high. We can also make some changes to the diet and monitor the vitamin D levels and iron levels to help children stop feeling tired. However in children whose GFR is extremely low we can replace the kidney and give them a new one from a family relative or a donor. The other option is something called dialysis where we can use a machine to do the job of the kidney and the blood is taken out of the body in a tube through the machine and returned back into your body. It sounds very futuristic! However for you Thomas, I would like to replace your engine with a brand new one that should help you feel back to your usual self.”
When Terry left, Thomas was thrilled, Terry would replace his engine so he would get his usual bright colour back and he could travel faster than he did before. It meant he could soon start racing Toby and Percy again and maybe even beat them this time!
For more information about chronic renal failure:
Not for profit organisation dedicated to helping people with kidney disease.