Hello just wondering ,I've heard from my doctors that my latest thyroid blood draw has shown up as abnormal and been traffic lighted at Amber .they plan to take another sample soon I think .
The labs have said to have a repeat blood test but it's not urgent.
I found out by ringing the receptionist for an update as I'm in shielding because of blood cancer.
I'd normally collect My results and check them myself .
My query is this, I have hashimotos disease with under active thyroid .
I usually have my bloods done early morning around 7 or 8 am .this wasn't possible as the nurse came to the house in the afternoon around 2pm .
Also I hadn't taken my levothyroxin that day until after the bloods draw but had taken it the previous day so a gap of 30 hours?
Normally I'd not take the thyroxine from the day before my bloods were due to be taken so maybe 24 hours clear.
Sorry I think I confused myself earlier saying 48hours ,I take my thyroxine when I get up every morning and would normally miss that dose the day before a blood draw 🙄not 2 days be for sorry .
I have modules and a cyst on my thyroid and they've been there for a couple of years I was assured that they would never turn cancerous.
So sorry for the long list but wondering what could have caused the abnormal reading .
thanks in advance to everyone who reads or helps .
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pet-lamb
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So sorry for the long list but wondering what could have caused the abnormal reading.
What are they classing as abnormal? We can't really comment without the results plus reference ranges.
I usually have my bloods done early morning around 7 or 8 am .this wasn't possible as the nurse came to the house in the afternoon around 2pm .
That will only affect your TSH result. It will be lower in the afternoon that it would be early morning.
Also I hadn't taken my levothyroxin that day until after the bloods draw but had taken it the previous day so a gap of 30 hours?
Normally I'd not take the thyroxine from the day before my bloods were due to be taken so maybe 48 hours clear .
Neither of those two timings is correct. There should be a gap of 24 hours between last dose of Levo and blood draw to give a measure of your normal circulating hormone. You will have had a false low FT4 with both those tests.
As you left 30 hours and your FT4 is probably low in range, I'm guessing that your TSH is low and that's why your being told your result is abnormal.
Can they not email results to you or give you the results/ranges over the phone (not ideal but you could read them back whilst on the phone to double check).
She should know that you are entitled to see your results and I would ask her to email them to you or post them to you. Just to add I have read my records from the last 10 years by logging into GP services because it is the law that I can read them and my results.
As long as you know that they must give them to you. A receptionist is just admin and is not medically trained and probably has no idea what your results mean. Some of the people on this site know more than she does and I am speaking from experience having worked for the NHS.
Thanks Lora yes I know and as I said I don't usually have a problem getting my results ,the ref was lovely just unable to help today .But I'm a bull dog I'll get those results soon ☺
If they do not give you your results in some form when requested, or offer to let you have them within 30 days, then they are breaking the law (assuming that you are in the UK).
Thanks Susie yes I know but I'm not pushing as I'm in shielding .Normally I don't have a problem getting them .it was the receptionist I spoke to and she didn't have a clue how to read the results.
I've asked them to email message or post my results in just waiting to see what happens.
of course if they come to my house again to repeat the blood tests they can bring them when they come .
First of all, I am very sorry you have blood cancer and I do hope the expert doctors can resolve this for you.
I believe it is because your bloods weren't drawn as early a.m. as possible and normally (as you would know - I think) we'd leave a gap of 24 hours between last dose and test and it is a fasting one and we take hormones afterwards. As the gap was 30 hours results would be skewed. I should also state I'm not medically qualified.
I'd ask for another test and just tell your GP that your results were skewed due to blood not being drawn early a.m. and too long a gap between last dose and test.
I wouldn't worry about it. Levothyroxine has a half-life of about 7 days. If you were to try and get an 'average' fT4 at 12 hours after the last dose you would have about 95.2% of your initial dose left. After 30 hours there is around 88.4% left. So, as a result of leaving it 30 hours your fT4 figure will be about 7% lower (or about 2% low compared to leaving 24 hours). Nothing to worry about.
Having fT4 around 7% lower will raise your TSH a little but an afternoon blood draw will lower it more. So I guess your TSH will come out a bit lower than with your usual routine. I believe your TSH is usually around 0.5? If so, I suspect it doesn't vary much during the day as it is already lowish (compared to the population, not saying it is too low).
Doctors tend to be unaware of the inverse log normal relationship between TSH and thyroid hormones so with a lowish TSH they fail to recognise that small absolute changes are significant.
I don't think there is anything to worry about.
POST EDITED TO CORRECT STATEMENT THAT LEVOTHYROXINE HALF-LIFE IS 24 HOURS.
For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12
Low vitamin levels are extremely common, especially as you have Hashimoto's
What vitamin supplements are you currently taking?
Ask GP to test vitamin levels if not been done for 6 months
As blood test was pm you may find TSH is lower than not Ignore low TSH, most important result is Ft3 (nhs rarely tests)
Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .
Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)
Private tests are available as NHS currently rarely tests Ft3 or thyroid antibodies or all relevant vitamins
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