What cause TSH and FT4 both go up?

[li17]

By looking at my blood test report on the day of my first afib episode, I notice TSH is 2.692 (range 0.55 - 4.78), FT4 is 1.78 (range 0.89 - 1.70).

I had a blood test just four days before the first afib, in that report TSH is 1.27, FT4 is 1.58.

I had never had any thyroid problem. To my understanding, TSH and FT4 should change oppositely.

Any one has idea about why TSH and FT4 both went up on the day I got the first episode? I asked my PCP, he simply said the test reports from ER are not accurate. I don't believe him.

[BobD Volunteer]

All I can tell you is that many blood tests are inaccurate. Time from draw to analysis can be critical in many tests (INR is one such) and it is not uncommon to find variations in quite short time frames.

[rosyG]

hi

My INR in A and E was 2/10 different from my own test done that day- readings do vary- just have another test after a while to check