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Date of last update: 10/09/2017.

Forum Name: Miscellaneous Nephrology Topics

Question: GFR

 worriedmomhere - Wed Sep 07, 2005 7:51 am

My GFR is 87 (I used a GRF calculator using my creatinine level). Does anyone know if that's good or bad? I'm a 34 year old white female. Does GFR really mean anything, or is it unimportant?

I see my neph. in less thank 2 weeks...hoping that she'll have some info on my HBP.

Thanks so much for any info you could offer me!
 R. Zein, Pharm D - Wed Sep 07, 2005 9:26 am

User avatar Glomerular filtration rate (GFR) is a measure of how well your kidneys
are filtering wastes from your blood. Your GFR is estimated from a routine measurement of creatinine in your blood.

Creatinine is a waste product formed by the normal breakdown of muscle cells. Healthy kidneys take creatinine out of the blood and put it into the urine to leave the body. When kidneys are not working well, creatinine builds up in the blood.

GFR of 87 is normal, based on the limited info you have provided

However, as we get older, the average GFR number drops. Low GFR with a value below 60 suggests some kidney damage has occurred. This means that your kidneys are not working at full strength.

GFR IS VERY IMPORTANT NUMBER as the doctor use it to as one clue to how well your kidneys are working. Your doctor will also look at other factors, including:protein (albumin) in your urine ,diabetes , and high blood pressure

Depending on these factors, your doctor may decide that you have chronic kidney disease. If you have chronic kidney disease, controlling your diabetes or high blood pressure can help prevent more damage to your kidneys and other problems like heart attacks and strokes.

hope that helps. thank you
 worriedmomhere - Wed Sep 07, 2005 1:35 pm

PharmacyDoctor, thank you for you quick reply.

I have been told that I've got CRI based on a renal ultrasound (see my post below this one: thinning parenchyma, increased resistive indices, small kidneys). Because I've already been dx'd with CRI, does that change anything with my GFR?

I've been having some high BP recently and and I'm scheduled to see my neph on the 20th. I'd love any more info you could provide me with!

Thanks again PharmacyDoctor for taking the time to explain GFR. I really appreciate your input.
 R. Zein, Pharm D - Thu Sep 08, 2005 9:46 am

User avatar Chronic renal insufficiency (CRI) is a condition in which the kidneys gradually lose their ability to perform their normal functions, such as the removal of wastes and extra fluid from the body.This means that they lose the ability to excrete wastes, concentrate urine, and conserve salt and water.

With reduced kidney function, there may be a certain amount of clinical and sub-clinical fluid retention in the body, due to poor elimination of fluids and poor control of sodium. Perhaps more importantly, the kidneys are a major component in the body's regulation of blood pressure. As such, the kidneys have their own ability to raise blood pressure via release of a hormone called renin. Release of renin triggers a cascade of events all over the body which eventually cause constriction of the blood vessels (vasoconstriction). This cascade of events is called the renin-angiotensin-system, or RAS for short. When the kidneys sense that the glomeruli (the actual filters in the kidneys) are not getting the blood perfusion that they need (this means good, adequate blood flow within the glomeruli), they cause release of more renin, and blood pressure is eventually raised throughout the body. Since chronic kidney disease does affect blood perfusion within the glomeruli, chronic kidney disease is almost always accompanied by hypertension to some extent, even if there is no fluid retention. Some high blood pressure medications work by inhibiting the renin-angiotensin-system specifically, and these are therefore most effective in the context of chronic kidney disease.

GFR OF 87 reflects a mild form of chronic kidney disease, the main point is to control your blood pressure and have freqquent checkups with your doctor.

AGAIN , this is important because the kidneys play important role in regulation of the blood pressure as they are responsible for sodium and water homeostasis. preservation of renal function is very important for controling blood pressure or hypertension. Meanwhile , controling bolod pressure is very important for the prevention of further kidney damage.

overall, since GFR is a reflection of kidney function, and having said that CRI is a form of mild kidney disease (GFR OF 87), GFR will increase as the kidney function deteriorates.

thank you and hope that helps.
 worriedmomhere - Sat Sep 17, 2005 3:29 pm

R.F. Pharm. D., I thank you for another in depth and informative answer!

You've given me a lot of good info to better understand what CRI is.

My appt is on Tuesday, and I'll update when I get back.

Thanks again for your input - it's very much appreciated!

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