Kidney Impairment

As NHS health-professionals we provide holistic care to our patients, and are used to doing this while intermittently focussing on different parts of the body or different bodily systems.
This provides a way of structuring care properly- taking into account the evidence there is for treatments provided.
This evidence and the way it is produced is compartmentalised, so it suits us when systematising care to break it down in the same way.

As doctors we have through our careers become quite accustomed to dealing with heart disease, brain disease, gut disease and so on. 

Kidney disease has always been a bit at the periphery of our awareness and care. (Apart from a relatively few doctors who are interested in the kidneys that is).

I wonder why that is.

I think it may be because, by and large, they just work.

Even when scraping along on 20% of their capabilities we really don't feel the effects.
If that was heart or brain we'd be acutely aware of it. Added to that, they seem a bit mysterious.
In medical school we are in awe of their fabulous structure and the beautiful, complicated way they work so well and wonder how on earth that ever evolved.

What is it they do?

Well, they essentially filter the blood. Filtering out molecules that aren't supposed to be in our bloodstream and keeping in the ones that are. This keeps us feeling healthy.
They also do a few other regulatory things like helping with the control of blood pressure and metabolising vitamin D to keep our bodies calcium levels normal and bones healthy.

Next question.... why are they so fault-tolerant?

This I think is because they are actually quite delicate and sensitive things.... being prone to damage they have a large built-in tolerance to it.
Any number of different conditions can damage the kidneys. Inflammatory and autoimmune conditions are ones that interest doctors quite a lot.
Diabetes is the big thing in kidney disease though. Renal units up and down the country are kept going by people with poorly controlled diabetes who have succumbed to kidney impairment of varying degrees. High blood pressure can be either the result of or the cause of kidney damage. One of the big ones is the damage that comes from poor circulation. Not just cold hands I mean, but clogged up arteries. The kidneys filter the blood, so if the blood can't get to or around the kidney to be filtered then the kidneys can't do their job.
Certain medications can damage the kidneys too. And poisons- a classic being poisonous mushrooms.

They tend to weaken as you age as well.

Next question... why am I writing about kidneys?

As kidneys are a bit of a "Cinderella" organ, yet so important,  the Department of Health has decided to kick us into action to look with more interest at kidney disease. Which probably needed doing.

The first thing they did was get all the laboratories in the country to give us our kidney-function blood tests in a different way that would be more meaningful.
Previously we got, and actually still do get, a level of a substance called creatinine.
This is a breakdown product of muscle metabolism. If we have muscles, we have creatinine in the bloodstream. If we have lots of muscle we have a higher level.
Our kidneys get rid of it at roughly the same rate that it is produced. If the kidneys don't work well then the level is higher.
What they have now done is age and sex adjusted this figure to give us a figure called an eGFR. This stands for an estimate of the Glomerular (kidney) Filtration Rate.
Now that we have these figures we more easily get an idea of whether someone's kidneys are working well or not.

So, what are we doing with these figures at Leatside?

Well, now we have a list of people where the blood tests suggest or hint at the fact that kidneys may not be working so well.

What we have to do is work out in which patients this is a significant problem or not. Thes we'll call CKD - Chronic Kidney Disease. Chronic refers to the duration an illness has gone on, not how bad it is. Chronos=time. Like chronometer.

One way of doing this is to see if the urine produced contains any protein. A damaged kidney leaks proteins from the bloodstream into the urine.

Another is to see if a patient with an eGFR that is out has any other condition that might cause or contribute to kidney damage. Diabetes, high blood pressure and so on... 

The other thing of course is the patient themselves. A bodybuilding muscle-man may have a very low estimatedGFR purely because they have so much muscle.
Someone who is missing a kidney may have a low eGFR but a perfectly healthy remaining kidney.

Once we have formed a clear idea about who might have actual, damaged kidneys then we can arrange care to reduce the risk of further damage and see if there is anything we can do to improve the situation.

What this usually entails is controlling better the factors involved that might be damaging, or might have damaged the kidneys. eg Better control of cholesterol and blood pressure. Tighter control of diabetes.

If, however, someone seems to have kidneys that are really not very good then we usually will refer them to a Nephrologist (Kidney Specialist) for a more expert view on what to do. 

We have a Kidney Specialist called Dr Tse from Derriford who does a clinic at Totnes Hospital, or we can get people to see the one who visits Torbay from Exeter Renal Unit.

The severity of kidney impairment is staged- 5 levels.

Stage 0 is normal, stage 5 is on dialysis.

Many of our patients have an eGFR indicating stages 1 or 2, but these really don't need much, if any, attention at present.

It is those people with stage 3 or 4 that we hope to find and work on.

I hope we already know all the patients with stage 5 disease. These are the ones who may need dialysis or a transplant.

So far we have identified over 300 patients with Stage 3,4 or 5 disease. We will be contacting them in due course individually to take this further if needs be. Our computer suggests we'll have nearer 400 in total.

More Info:

UK National Kidney Federation - http://www.kidney.org.uk

The Renal Association - http://www.renal.org/whatwedo/InformationResources/CKDeGUIDE/CKDstages.aspx