>> Welcome to the ABCs of Kidney Disease.
I'm Daphne Knicely,
and today I'm gonna talk to you about
the causes and stages of chronic kidney disease.
This video is a part of the Johns Hopkins Nephrology
Patient Education Program,
and we'd like to thank our sponsors,
The Ed Kraus Endowment and the Shah Foundation.
So chronic kidney disease
is a silent problem in the United States.
There are 30 million people in the United States alone
that have kidney disease.
That's about one in seven people.
And the crazy fact about this is 97% of them
have absolutely no idea they have kidney disease.
That's because most of the time kidney disease is silent.
There is no symptoms until you've basically lost
90% of your kidney function,
and you're getting close to needing dialysis.
Now a lot of people are at risk for kidney disease.
One in three patients with diabetes is at risk.
One in five with high blood pressure is at risk.
Also those that are over the age of 60,
that are obese, have cardiovascular disease,
or certain ethnic groups are at risk for kidney disease.
So how do we screen or diagnose for kidney disease?
Well, there are two tests that I use.
So, one is a urine test.
It's a urinalysis or urine dipstick,
and really what I'm looking for
is blood or protein in the urine.
You should not have blood or protein in your urine.
They're actually really big molecules.
So the example I like to use.
It's like pasta falling through a strainer.
It shouldn't happen.
Or for the kidney,
it tells me that there's damage to the kidney's filter
that's allowing protein or blood to fall in the urine
which should not happen.
And sometimes people will have...
This is their first sign of kidney disease
before they have any chemistry changes.
The next test I use is the blood creatinine test.
So creatinine comes from muscle.
It's just a normal waste product,
but you only get rid of it through your kidneys.
So when it goes up in the blood
I know the kidneys aren't working perfectly.
But it's not a perfect test.
It I have a 90-year-old woman that maybe weighs 90 pounds,
and I have a big body-builder, a 20-year-old,
who weighs like 300 pounds of solid muscle,
they have different muscle amounts,
and so they're generating creatinine at a different rate.
But maybe they both have a creatinine
in their blood test of one, which is normal.
But what it tells me is that body-builder
is working overtime to get rid of creatinine.
His kidneys are perfect.
Whereas that 90-year-old woman,
her kidneys might not be working as perfect as they used to,
'cause really she has no muscle mass
and her creatinine probably should be 0.5.
But instead of me guessing this,
we have something called a Glomerular Filtration Rate,
and it's really a calculation
where we take into account your age, your race, your gender,
and your creatinine level.
And so what happens is
if your creatinine goes up in the blood,
I think your kidneys aren't working great.
Well, the Glomerular Filtration Rate works the opposite way.
It decreases when your kidneys aren't working great.
So they move in opposite directions.
So what really is this Glomerular Filtration Rate?
Well, it's literally a measure
of how many milliliters per minute
of blood your kidney's filtering.
But, for me, it tells me how much function
of your kidney that you have.
So normal is about 90 to 100,
and it decreases as they kidney ages over time
and as the kidney disease gets worse.
And I use this Glomerular Filtration Rate
to stage kidney disease.
So what are the stages of kidney disease?
So there are five,
and the first stage is when that Glomerular Filtration Rate
is more than 90.
But maybe I know that there's damage to the kidney.
Maybe I have a kidney biopsy.
Maybe I have blood or protein in the urine.
Then stage two is from 60 to 90,
stage three is from 30 to 60,
stage four is from 15 to 30,
and stage five is less than 15.
Usually as a kidney doctor,
I don't start seeing patients
till around stage three, four, or five.
And most of the time if somebody's in stage four,
that's when I start the discussion with them about
well in the future if your kidneys got worse,
are you thinking about dialysis or a transplant,
and I talk to them about the options.
We don't start it then, but we start talking about it.
And then in stage five, really it's not until that
Glomerular Filtration Rate is about five to 10
before people start to develop symptoms of kidney disease.
And that's when they usually need to start dialysis.
So I use the stages of kidney disease a lot
as a kidney doctor.
One, it tells me how well your kidney disease,
if it's progressing or not,
and two, it tells me how often do I need to get labs
and how often I need to see you in clinic.
'Cause somebody in stage two compared to stage four,
I'm not gonna see someone in stage two that often,
maybe once or twice a year,
whereas somebody in stage four
I might see every three months or every two months.
It depends on how their kidney function is trending.
There are a lot of different causes
for chronic kidney disease,
but the number one in the United States
and in any developed country is diabetes.
Diabetes can affect any organ in the body,
and it's known to affect the kidneys if it's not controlled.
High blood pressure is the number two cause
for chronic kidney disease in the U.S.
And then after that it's kind of a mixture of things.
So there's a category called glomerulonephritides
or glomerulonephritis,
and really this is a group of diseases
where your body's attacking your kidneys.
You're making some sort of antibody
maybe due to things like lupus or something else,
or you have a disease specific to your kidney
like IgA nephropathy or membranous nephropathy.
Some other causes.
There's inherited diseases.
So a good example of this
would be like polycystic kidney disease
where your entire kidney gets replaced by cysts.
Then we have some other diseases.
So like urinary tract obstructions.
So most common is for men having prostate problems.
Well, like I explained in one of our other videos,
is from going from your bladder out of the body
is your urethra, and for men,
that goes through your prostate.
So if your prostate enlarges
it basically pinches off that tube
and you can't get rid of urine.
Well that backs up to the kidneys and causes damage.
For women, this could be uterine fibroids
that can cause obstruction or blockage.
Also repeated kidney infections
can cause damage to the kidney.
So I have a actual infection of my kidney,
that can cause scarring over time.
And then sometimes we have medications.
Every medication has side effects,
and sometimes medications are necessary,
but sometimes those medications
can cause damage to our kidneys.
If you're interested in learning more
about chronic kidney disease, causes and stages,
then check out our resources.
Also if you wanna know about normal kidney function,
the complications of kidney disease,
or treatment of kidney failure, check out our other videos.