Wacked out lab result

[veritas]

Just received my labs as of 1/20:

All values fell in the "normal " range with the exception of :

BUN - 29 (high)

AGAP - 4 (low)

All others fell in range:
creat 1.1, gfr>60, glu 82, TP-7.4, alb-4.6, ast-20, alt-23, K-4.2, cl - 107

There was also a trace of protein in urine. All other values normal. (RU creat 184.6, RU prot 18)

I'm having a bit of a problem figuring it out. I do eat a high protein diet and exercise frequently but those numbers kinda threw me.

Any advice?

v

[Miss Philicia]

Possibly kidney related, no?  But from time to time, though not often, I'll have something out of whack and by the next test it's fine so I'm not sure I'd fuss unless my doctor thought it necessary.  So yeah, what did your doctor say?

[John2038]

Hi Veritas,

First at all, and as you know, you will have to discuss with your ID doc about your labs results.

In the meantime, here are just personal assumptions with very limited values.
First, I would check if the Viread is not the culprit of your slightly low level of AGAP (ref range 5-16 in my lab). As you know, Viread can be the cause of renal tubular injury.
Now your creatine clearance looks normal as well as your albumin.

You may also check your level of sodium (if it is too low) and magnesium (if it is too high), as both may lead to a low AGAP value.

Others reasons can cause a low AGAP value and it is again important to talk to your id doc.
Regarding your BUN, a high protein intake can be the cause.

Keep us informed.

Best Wishes my friend,

John

[veritas]

Haven't seen the doc yet --- next week. I thought that it could be a lab error since all my other kidney function tests were within the normal range ,but the BUN coupled with the trace protein in urine and low anion gap has got me a little concerned.
Of course kidney problem is the first thought, but I believe there would be other indicators such as creat, TP, K-value, gfr etc.

Puzzling.

v

[John2038]

Absolutely. Don't forget also that AGAP = S-Sodium - S-Chloride - S-Tot CO2 (Bicarbonate)
Your others GFR results should give you more clues as well as doing another lab.

Best
John

[veritas]

John,

Thanks for your reply.

 Low agap can come with some ugly stuff (one of the banes of doing research). But until I get some confirming tests , it's hope for the best.

Thanks again, John.

v

[bocker3]

V -

Certainly you would want to follow up on these -- but besides these being outside of the reference range -- how different are they from YOUR usual results.  Remember reference ranges are for a population and may not necessarily apply to every individual.  If you were on the low end of the range in the past (and not trending down for a while), there is far less concern for a couple of slightly low results.

Also -- a trace protein result in the urine is not at all uncommon.  There are a whole bunch of things that can cause it that are not "issues" -- including timing of the specimen, so again -- I would stress over this.

You are correct though -- a little knowledge can be a double edged sword.  Try to keep away from worst-case scenarios -- even if something is going astray with your kidneys, you are catching it early here.  Let you doc weigh in and, of course, insist on a repeat sooner vs. later.

Let us know how things go......

Mike

[veritas]

Mike,

I went back on my labs for two years and found that my numbers for agap have been on the low side for quite awhile and not necessarily in the normal range. Then I did some further research on the calculation for agap as John mentioned. I found that the lab I'm using takes the shortversion  of the calculation (without potassium). I recalculated on the alternative equation, the result fell in the low-normal range (8.1) when I included potassium.  How do you spell RELIEF!

Will still follow=up with my doc next week.

Thanks for the input guys, you made me think and look at the problem logically. I learned something to boot ---- How to calculate agap. If nothing else with this disease, your forced to learn a lot. I guess that's a good thing.

v

v

[John2038]

Hi Veritas,

Glad you have found some RELIEF !

For info, here are my AGAP values (without/with including the Potassium):

Jan 2009: 8 / 12.3
Feb 2009: 4 / 8.4   (<-- welcome to the club neh ?)
Dec 2009: 11 / 16.5

The normal value for the anion gap without the Potassium depends on the labs:
For some: 8-16 meq/L For mine: 5-16 meq/L

Calculator here

Note:
some newer references will list the normal anion gap as 7 +/- 4.
This lower level may represent a more accurate reflection of the true anion gap based on changes that have occurred in contemporary medical labs. In the past, electrolyte analysis was performed using predominantly flame photometer measurement compared to the modern day use of ion-selective electrodes. Previous measurement techniques tended to underestimate the value of chloride, which led to a higher calculated anion gap.
Source

More Stuff


Keep Well !

John

[veritas]

 Thanks John !

 v