Would glucose water consumption alter potassium levels?

Hi doctor,

The patient is a 28-year-old male. He had diarrhea for about 25 days, out of which about one week was severe (had around 85 times in a week), and hospitalized. While in hospital, he had increased potassium (4.7) and was given a nebulizer for two days. He lost about 10 kg during this episode. On the discharge, potassium was 4.4 and they said it was normal. This happened two months ago and from the day of discharge, he has been normal. He travels a lot and has erratic sleep patterns. Though he has adequate sleep, he sleeps very late at night. He has a history of GERD, but not under any medication now.

Yesterday, we visited a urologist for UTI-like symptoms. They checked urine sample and also took a blood sample. All other parameters were normal, except potassium and it was 6.2. They said it was abnormal and asked to get another test done today. Yesterday, since the laboratories were not open, a friend (general medicine doctor) suggested having glucose as a home remedy. We again gave the blood sample this afternoon around 12 and the reports showed potassium as 4.4. We then consulted a general medicine physician today. He examined and asked a thorough history. He said that there is nothing to worry and that was a sampling error due to some cell breakdown. Please explain what to do next. I have a doubt if that glucose would have reduced potassium levels to 4.4 and would have misled. Should we get the test done again? If yes, when? Thank you and awaiting your reply.

Thank you doctor,

I forgot to mention one more thing. He had glucose water on the previous night and there were 14 hour gap between the blood test and the time the patient had glucose. Still, can it be a cause?