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Contrast vs kidney function

Steve.Adam's picture
Steve.Adam
Posts: 463
Joined: Oct 2016

Hi Kat23502, this one is for you (or anyone).

How dangerous is IV contrast for kidneys? I read that single kidney owners should avoid it.

'Lefty' was working perfectly before its twin's demise.

Should I be worried about contrast scans. I much prefer NO risk to calculated risk.

Steve.

corey50
Posts: 111
Joined: Feb 2009

I'm assuming you're asking about IV contrast because you have an imaging test coming up. Before any testing your doctor should order blood tests that check your kidney function. If your kidney function is within normal range for someone with one kidney then you can have the contrast, it will be safe. If not your doc should let you know and you can have the test without contrast. I would always have my bloodwork done at a lab affiliated with the hospital i was having the scan at so the tech could actually check the blood results right on her computer before the test. Fortunately mine were always fine. They will also give you an IV saline flush after the contrast. Drink lots of water after the test too to keep flushing your kidney. Don't worry, if the doc says your bloods ok, you'll do fine. Good Luck.  

sucotai
Posts: 19
Joined: Jan 2017

Having a single kidney is not a contraindication for CT contrast. Hospitals will check your Cr and calculate something called eGFR which estimates your renal function. As long as your eGFR is good (>60, some places may take >50) then CT contrast should not be a problem They may switch up to a slightly safer but much more expensive (hence not used for everyone) contrast if your eGFR is close to the cutoff. CT contrast does have notorious nephrotoxicity (e.g. toxic to kidney), and can lead to acute renal failure in some people. In someone with a reduced renal function, that toxic effect can be even greater since they have a much harder time getting rid of the contrast from their body. But in most people with good renal function (regardless of 1 or 2 kidneys), the risk is low. They will give you the routine normal saline and monitor you etc etc, but your risk of acute renal injury is not higher than the average population as long as your eGFR is good as far as the radiologists are concerned.

donna_lee's picture
donna_lee
Posts: 1003
Joined: Feb 2009

Even on the first one to further Dx what the US found.  The Dr and the facility have gotten more vigilant/strict over the years, so I have a CMP blood test a week prior to the test, just to make sure they can use dye.  I also have a liter of fluid pre and post on the test to help the remaining kidney flush the dye; and this has been going on for 10 1/2 years.

That said, the age factor plays in here.  My eGFR, post nephrectomy, has never been above 43.  Ideally, my age bracket for 2 kidneys would be about 60.  So the Dr. looks at several variables.

So the let the blood tests determine what they do with the CT and don't worry about it.

donna_lee

 

todd121's picture
todd121
Posts: 1449
Joined: Dec 2012

The guideline is based on kidney function. My oncologist uses a creatinine of 1.5. If my creatinine is below 1.5, I get the contrast. If not, I don't get the contrast.

I asked my nephrologist about this. She's even comfortable with me getting the contrast with a creatinine higher like 1.7-1.8 where mine has been. She said she doesn't think it's risky if 1) I'm very, very well hydrated and 2) there's a medication they can give you to help when having the contrast.

Todd

foxhd's picture
foxhd
Posts: 3183
Joined: Oct 2011

peoples concerns, and variations in procedures. I guess I expect health care procedures would be more  similar. Like Mc donalds. There is no established norm in a lot of our care. Facilities, Dr.s', even geological location usually do things differently. I am in a good location and I'm happy with the protocols. It is a liter of contrast an hour before cts, and then reduced iv contrast. I'm fortunate in my remaing kidney function. It has always been good.Even after nephrectomy. GFR always over 60. Creatinine, .8. I'll bet my cancerous kidney hadn't worked well in a long time. Leading to a hypertrophic functioning kidney. My mother and sister died from kidney disease. If it wasn't for cancer, I might be dying from kidney disease.

Steve.Adam's picture
Steve.Adam
Posts: 463
Joined: Oct 2016

That's a beautifully crazy irony.

Kat23502's picture
Kat23502
Posts: 179
Joined: Feb 2016

If your kidney function is good, we don't alter exam protocols for a single kidney. The risk with contrast dyes is mostly due to something called CIN or contrast induced nephropathy. The risk for CIN is mostly linked to kidney function (and other coexisting conditions such as diabetes) with the risk of CIN increasing with decreasing kidney function. There are things we do to reduce the risk such as lower volume of contrast. We utilize GFR instead of creatnine. Creatinine was the standard for many years but has been largely replaced by GFR recently.

 

As a side note, kidney damage (and some other rare conditions associated with contrast use) is actually quite rare and when they do occur they often times are self limiting. However, best to be overly cautious than risk damage. 

Steve.Adam's picture
Steve.Adam
Posts: 463
Joined: Oct 2016

Thanks Kat and everyone.

I won't worry about it too much when the time comes but I will certainly discuss it with hospital staff to be sure.

Steve.

 

Kat23502's picture
Kat23502
Posts: 179
Joined: Feb 2016

I wouldn't worry too much. It's definitely a risk vs benefit sort of thing. IV contrast is the gold standard to use when imaging the kidneys for neoplasm. If your kidney function is good, then to me, the benefit outweighs the risk. However, much like what Fox said, these things are really dependent on so many individual factors. Maybe read up on contrast induced kidney injury and I bet that would make you feel better. You can search for contrast induced nephropathy (CIN) as well as contrast induced acute kidney injury (AKI). There is one other but that's for people getting gadolinium contrast for an MRI. Like I said, if you read up on it the info about how rare it is and the risk will likely make you feel better.

todd121's picture
todd121
Posts: 1449
Joined: Dec 2012

Kat,

After my last surgery (laparascopic adrenalectomy) I had a very weird reaction to the gadolinium contrast. I was very allergic to the surgical glue and my wounds healed up very, very slowly. When I had an MRI about 2 months after my surgery with gadolinium contrast, all my scars from the recent adrenal surgery swelled, turned bright red, and were very itchy. They called the head of radiology to come down and have a look. It appeared they'd never seen that before. Even the head of radiology seemed suprised. He said he guessed I was having an allergic reaction to the gadolinium.

In my experience, the first allergic reaction like this is somewhat subdued compared to follow on allergic reactions. In the future I'm wondering if I should have gadolinium contrast or not.

Have you ever seen this or heard of it? Do you think taking gadolinium contrast in the future would be risky?

I've heard more stories of people allergic to the sugical glue. My first laparascopic surgery (nephrectomy) I had no problem with the glue at all. Everything healed beautifully. The second surgery I had a very ugly reaction to the sugical glue and it caused my wounds to heal very badly. I never could find out if it was because I had a different glue or if it was the same glue and I just didn't have the allergic reaction the first time around. The sugeon on the second sugery didn't really seem to care much about the allergic reaction. It made me pretty damn mad that they didn't seem to care much about allergic reactions to the glue they are using to speed up their closing.

Thanks for your insight to the contrast discussion.

Regards,

Todd

Kat23502's picture
Kat23502
Posts: 179
Joined: Feb 2016

Hey Todd,

 

i have to say I haven't ever heard of this. I have heard of gadolinium skin reactions but not specific to scarring. Just a thought, MRI can in theory burn skin, have you had an MRI without gadolinium with those scars with no issues? There is research that indicates if there is an area of skin where blood flow is reduced, the thermal energy may not redistribute itself as quickly and evenly causing thermal burns. So if your wounds caused some delay in blood flow, in theory, it's possible it was from the scan itself over time and not the contrast. 

 

That being said, a point about gadolinium, for sake of being thorough in answering your question. The most recent accepted research states that some amounts of gadolinium remain in the body, particularly in the brain and bones. This retained gadolinium remains in these tissues and can accumulate over time. The effects, if any, aren't fully understood or known. It's a significant enough finding that this is usually discussed with our patients prior to imaging when it previously wasn't. 

 

Lastly, any contrast reaction is thought to have the possibility of being more extensive each time contrast is given. For this reason, and the fact that research has proven gadolinium can remain in tissues is something to consider. Have you discussed premedication for your scans to help offset possible reactions?  There is a protocol of a combination of prednisone, and Benadryl, and some doctors add Tagamet, that can be used in patients that have shown mild reactions previously. This protocol decreases the risk of worsening reactions. 

 

Hope that helps!

CRashster's picture
CRashster
Posts: 241
Joined: Mar 2017

My last scan my GP was very much against me taking constrast. So much so, that I did not. My eGFR was low. However, it is now getting better and both doctors are in agreement that next time, I get contrast. The warm sensation isn't bad.

Hd67xlch's picture
Hd67xlch
Posts: 152
Joined: Apr 2016

I'm having my 90 day scans right now my creatine was 1.4 and gfr was 55 so I'm getting contrast today

CRashster's picture
CRashster
Posts: 241
Joined: Mar 2017

A 55 GFR is pretty good.

faithlou's picture
faithlou
Posts: 41
Joined: Jan 2013

No contrast for me.  My creatnine runs 1.7.  Scan police will not do it. Good conversation.  I will talk with the Doctor about the GFR.

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