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When Would AGAP Measure Be Elevated While Getting Treated For Food Poisoning?
Question: I had two sets of labs drawn about a month apart. When I did the first set (March) I had been sick with food poisoning or something so I was dehydrated. I was not dehydrated when I did the second set (April). The main reason I had the second set was that the creatinine was elevated on the first set. It wasn't on the second. However, the potassium was elevated on the second set (5.3) and so I re-tested only the potassium two days later and it came up as (3.6). There had been no diet or medication changes between the two potassium tests (both were fasting) so I suspect the blood sample was slightly hemolyzed, although the lab did not detect that.
That leads to my first question. Is it possible that the sample was slightly hemolyzed and the lab couldn't tell? Is that the most likely cause of the isolated high potassium?
My second question is the AGAP. It was elevated on both tests, but more elevated on the second. 16.4 to 22.3. What does AGAP measure and can you think of any reason it would be elevated?
That leads to my first question. Is it possible that the sample was slightly hemolyzed and the lab couldn't tell? Is that the most likely cause of the isolated high potassium?
My second question is the AGAP. It was elevated on both tests, but more elevated on the second. 16.4 to 22.3. What does AGAP measure and can you think of any reason it would be elevated?
Brief Answer:
Nothing to worry much about numbers.
Detailed Answer:
Hi, dear
I have gone through your question and your both reports. I can understand your concern.
First of all your creatinine level is normal in second test which can be elevated in first due to dehydration. So that is OK.
In second test your potassium level is high normal and after retesting it becomes normal.
Most common cause of high potassium without any medical problem are hemolysis, diet and drug.
Slight hemolysis can leads to RBC breakdown and it increase your potassium level in testing. It is quite possible that laboratory will not say that sample was hemolysed. You have done in fasting level so diet will no effect in your case. Moreover drug like lisinopril can leads to high potassium in some cases but in your case no change in drug so it can be due to hemolysis most likely.
Whatever the cause may be, but your latest potassium level is normal so forget everything and just be relaxed.
AGAP is a short form of Anion Gap.
Anion Gap measures ions present in blood. When there is high amount of acid in blood Anion Gap is increased. It generally measures from equation based on sodium, chloride and bicarbonate in blood. You have slightly high Anion GAP but all other parameters are normal so in my opinion it is not significant.
Only significant thing is your positive occult blood test in stool which indicates some bleeding from gastrointestinal tract. For that please contact your doctor.
Hope I have answered your all questions. If you still have any doubts then feel free to ask me. I will be happy to answer. Thanks for using health care magic. Wish you a very good health.
Nothing to worry much about numbers.
Detailed Answer:
Hi, dear
I have gone through your question and your both reports. I can understand your concern.
First of all your creatinine level is normal in second test which can be elevated in first due to dehydration. So that is OK.
In second test your potassium level is high normal and after retesting it becomes normal.
Most common cause of high potassium without any medical problem are hemolysis, diet and drug.
Slight hemolysis can leads to RBC breakdown and it increase your potassium level in testing. It is quite possible that laboratory will not say that sample was hemolysed. You have done in fasting level so diet will no effect in your case. Moreover drug like lisinopril can leads to high potassium in some cases but in your case no change in drug so it can be due to hemolysis most likely.
Whatever the cause may be, but your latest potassium level is normal so forget everything and just be relaxed.
AGAP is a short form of Anion Gap.
Anion Gap measures ions present in blood. When there is high amount of acid in blood Anion Gap is increased. It generally measures from equation based on sodium, chloride and bicarbonate in blood. You have slightly high Anion GAP but all other parameters are normal so in my opinion it is not significant.
Only significant thing is your positive occult blood test in stool which indicates some bleeding from gastrointestinal tract. For that please contact your doctor.
Hope I have answered your all questions. If you still have any doubts then feel free to ask me. I will be happy to answer. Thanks for using health care magic. Wish you a very good health.
Above answer was peer-reviewed by :
Dr. Remy Koshy
Thank you for your answer.
I'm sorry about not mentioning the blood in the stool. I have been trying to forget about that because it was gross. It was caused by infective colitis. I had a colonoscopy. It was gone in a week, so that is fine.
I appreciate the information about the hemolysis. I have one follow up question.
I read this article online and it looks legit to me, but I wanted to double check it with you.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC0000/
My particular question is about the section where they discuss "Mechanical Factors." The article says that the tourniquet should not be left on the arm more than one minute and that fist clenching is not recommended. Does this fit with your knowledge and experience?
When they collected the blood the tourniquet was on much longer than one minute. I can't say how long for sure, but my veins are difficult to locate and they were training someone new that day. The two of them went back and forth several times poking at my veins with their fingers before they finally stuck the needle in. They also instructed me to clench my fist, which I did.
The reason I really want to know if this is a possible contributing factor, is that first they charged me twice for the potassium test, and second I have some medical anxiety and I worried way too much about that potassium reading while I was waiting to get it tested again.
If I can keep it from happening again by making sure they don't do that, it would help my anxiety.
Thank you again.
I'm sorry about not mentioning the blood in the stool. I have been trying to forget about that because it was gross. It was caused by infective colitis. I had a colonoscopy. It was gone in a week, so that is fine.
I appreciate the information about the hemolysis. I have one follow up question.
I read this article online and it looks legit to me, but I wanted to double check it with you.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC0000/
My particular question is about the section where they discuss "Mechanical Factors." The article says that the tourniquet should not be left on the arm more than one minute and that fist clenching is not recommended. Does this fit with your knowledge and experience?
When they collected the blood the tourniquet was on much longer than one minute. I can't say how long for sure, but my veins are difficult to locate and they were training someone new that day. The two of them went back and forth several times poking at my veins with their fingers before they finally stuck the needle in. They also instructed me to clench my fist, which I did.
The reason I really want to know if this is a possible contributing factor, is that first they charged me twice for the potassium test, and second I have some medical anxiety and I worried way too much about that potassium reading while I was waiting to get it tested again.
If I can keep it from happening again by making sure they don't do that, it would help my anxiety.
Thank you again.
Brief Answer:
Explained in details.
Detailed Answer:
Hi, dear
I have gone through your question. I can understand your concern.
Mechanical factors means factors starts from blood collection to testing.
Ideally clenching and long tourniquet should be avoided. But in real practice even we also use
cleanching to make vein prominent. These are very minor factors and most of the time it doesn't affect much. But mechanical trauma to RBC in preparation of blood test causes hemolysis.
We generally don't charge for repeat testing but it depends on individual laboratory.
Now forget about your old potassium and creatinine level. Just be relaxed. Nothing to worry.
Hope I have answered your question. If you have any doubts then feel free to ask me. I will be happy to answer. Thanks for using health care magic. Wish you a very good health.
Explained in details.
Detailed Answer:
Hi, dear
I have gone through your question. I can understand your concern.
Mechanical factors means factors starts from blood collection to testing.
Ideally clenching and long tourniquet should be avoided. But in real practice even we also use
cleanching to make vein prominent. These are very minor factors and most of the time it doesn't affect much. But mechanical trauma to RBC in preparation of blood test causes hemolysis.
We generally don't charge for repeat testing but it depends on individual laboratory.
Now forget about your old potassium and creatinine level. Just be relaxed. Nothing to worry.
Hope I have answered your question. If you have any doubts then feel free to ask me. I will be happy to answer. Thanks for using health care magic. Wish you a very good health.
Above answer was peer-reviewed by :
Dr. Remy Koshy
Thank you for your time. I really am not seeking reassurance from you, although it is appreciated. I'm seeking knowledge. I already know there is nothing seriously wrong with me now.
However, I recently had a very difficult experience with a doctor. He pressured me into getting a colonoscopy which turned out to be not needed, according to the surgeon who did it. My symptoms did not warrant it, but I did have to pay for it. Then based on that one isolated high creatinine level and a level in 2014 that he found in my records (when I was also sick), another doctor diagnosed me with chronic kidney disease. I obviously don't have that based on the retest of the labs, which I also had to pay for. Then in that retest the potassium was high, so they made me retest yet again, and charged me once more.
I know I'm not sick now, but I will be again someday and so I feel like I need to learn as much as I can about this stuff so that none of these guys kill or bankrupt me.
Thanks for you time.
However, I recently had a very difficult experience with a doctor. He pressured me into getting a colonoscopy which turned out to be not needed, according to the surgeon who did it. My symptoms did not warrant it, but I did have to pay for it. Then based on that one isolated high creatinine level and a level in 2014 that he found in my records (when I was also sick), another doctor diagnosed me with chronic kidney disease. I obviously don't have that based on the retest of the labs, which I also had to pay for. Then in that retest the potassium was high, so they made me retest yet again, and charged me once more.
I know I'm not sick now, but I will be again someday and so I feel like I need to learn as much as I can about this stuff so that none of these guys kill or bankrupt me.
Thanks for you time.
Brief Answer:
You are most welcome.
Detailed Answer:
It's OK. No need to reassure you. You know that nothing is serious so it's fine.
Charges of retesting depends on laboratory policy. Some laboratory takes charges for retesting. Some are not taking charges. But it is good to have knowledge about this little things so that in future you don't have this kind of problems. And one more suggestion. Always test your blood in reputed laboratory.
Feel free to ask me anything in future.
Thanks
Have a great health ahead.
You are most welcome.
Detailed Answer:
It's OK. No need to reassure you. You know that nothing is serious so it's fine.
Charges of retesting depends on laboratory policy. Some laboratory takes charges for retesting. Some are not taking charges. But it is good to have knowledge about this little things so that in future you don't have this kind of problems. And one more suggestion. Always test your blood in reputed laboratory.
Feel free to ask me anything in future.
Thanks
Have a great health ahead.
Note: Do you have more questions on diagnosis or treatment of blood disorders? Ask An Expert/ Specialist Now
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
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