Elevated potassium

[KateMiskin]

I recently did some blood tests and GP found slightly elevated potassium. They asked me to come back again for a retest in case it was a false positive. But the nurse has been sick so I have got a date only in early March.

I wouldn't be worried except they keep sending me messages about what to do in case of kidney failure and chest pains. I have no alarming symptoms. Surely if I had kidney failure, I would know about it?

It rather depends on the result. If it high but in range then it will be fine. If it was vastly high they would have sent you to A&E.

It's 5.7 mmol which seems only slightly elevated, though I know very little about it. Normal range appears to be 3.30 to 5.30. Is it worth badgering them for a quicker appointment? I think not as I don't have any symptoms.

I think it's probably worth badgering.

Gosh, ok thanks.

Not hugely raised, but not that useful on its own without knowing the rest of your kidney function and electrolytes....

If you were a hospital inpatient id be looking hard at why it's raised, and rechecking within 24 hrs.

One of the issues with bloods taken in primary care is that depending on when it was taken and what the transport arrangements are, the samples can be sitting around for quite a long time, and delays in processing can cause elevated potassium levels.
I had that exact scenario happen to me when I had some pre op bloods done at the GP some years ago. I had the blood taken in the afternoon and it missed the last transport to the lab so sat in a box all night, got collected mid morning next day and then driven around town collecting from other surgeries so it was 24 hours old before it got to the lab and the potassium was quite elevated. I got it done again at work where it was processed much more quickly and it was completely normal.
Obviously I can't say if that's the case with you or not, and it definitely does need to be rechecked, but don't immediately think the worse. Might be worth asking if there's a phlebotomy service at your local hospital and going there instead?

@AgeingDoc that's likely what has happened but I will go back and try to get an earlier test.

I’m in the same boat OP, had blood test on Tue and when I checked the results online today it said potassium 5.9 and repeat test required. Everything else was within normal range. I haven’t even been contacted by my GP yet, so now I’m wondering if I should ring them tomorrow morning.

I had the reverse. Mine were 3.3 and the GP asked me to come in for a re-test to be sure. They then came back at 3.1, and I figured they would just tell me to eat some bananas.

Instead the GP rang and said I had to stop one of my BP meds immediately. I protested because it was the first time in years my blood pressure was below 170/110 and I felt good! He said "Well yes... but you might die. So stop taking it. (He was right, it turned out that I was in atrial fibrillation because of the lower potassium.)

Now I'm at 170/117 and waiting for next steps. But my impression was that relatively minor changes could be a problem. So it makes sense to set your mind at ease.

You may want to have a read up on Addisons disease and ask for an early morning cortisol blood test if you have any of the symptoms. Raised potassium is one of the flags (it is not present with secondary adrenal insufficiency which also causes low cortisol but is specific to primary adrenal insufficiency / Addisons, it’s complex). It’s very rare but something to be aware of.

I called my GP surgery this morning, they said doctor doesn’t think it’s anything to worry about, but to up my fluid intake and repeat the test in 2 weeks.

Update: had my repeat blood test today and the potassium was down to 5.0, within normal range. I have been drinking a lot more water over the last couple of weeks, so maybe the first high result was due to dehydration.