Kidney function and hypothyroidism?

[Agitator23]

My hypothyroidism was finally acknowledged six weeks ago. I've been on 50mcg daily. I've just had the first blood test since starting treatment.

My fT4 has 'risen' from 8.8% to 9.3%. My TSH has dropped below 1 (0.7) for the first time according to blood tests going back to 2007.

I'm a bit disappointed it's such a small rise but I think there's a lot of time to make up for...

What's really troubling is that I seem to have a kidney function problem. I have had right flank ache on and off for years. It's always been put down to muscle issues. I decided I'd have a private urine analysis dip stick two weeks ago. It came back protein positive.

My surgery did more tests based on this - further urinalysis and kidney function blood test. It seems I have albuminuria - losing albumin through the kidneys. I did notice last year that a general blood test came back with serum albumin being at the lowest possible point. I've also looked back on the NHS app and my kidney filtration rate (eGFR) was actually below range on at least one occasion. This was not picked up and I wasn't notified.

I have a couple of questions. Firstly, could l have been losing fT4 this way for years? Could this be why my fT4 hasn't risen but TSH dropped whilst on Levothyroxine? Does hypothyroidism cause kidney issues with a lowered eGFR?

I always wondered if being undiagnosed and untreated would cause long-term problems and possible organ damage. I even brought this up with my GP on several occasions 😕

Has anyone else got similar kidney problems? How does this affect dosage of Levothyroxine? Has Levothyroxine helped with kidney function?

Lots of questions! Many thanks in advance 🙏

[SlowDragon Administrator]

Poor kidney function is directly linked to being hypothyroid and will improve as dose levothyroxine increases

Don’t be surprised if GP is unaware of the link

ncbi.nlm.nih.gov/pmc/articl...

The GFR is reversibly reduced (by about 40%) in more than 55% of adults with hypothyroidism

There is a reversible reduction in the kidney to body weight ratio in hypothyroidism, where the renal mass almost doubles with treatment. Hypothyroidism results in a reversible elevation in serum creatinine due to the reduction in GFR as well as possible myopathy and rhabdomyolysis. There is a reduction in serum cystatin C levels in hypothyroidism due to reduced production, consequent to reduced cellular metabolism.[30] Both these changes are reversible with treatment of hypothyroidism. Hypothyroidism also results in increased glomerular capillary permeability to proteins.[47] The consequent proteinuria often precedes the reduction in GFR in hypothyroidism.[48]

50mcg levothyroxine is only standard STARTER dose

You are ready for next increase to 75mcg

Retest again in another 2-3 months

Essential to test vitamin D, folate, B12 and ferritin if not tested recently

Important to maintain GOOD vitamin levels

What vitamin supplements are you taking

[Agitator23 in reply to SlowDragon]

Thank you! Very reassuring ☺️

[Agitator23 in reply to SlowDragon]

Not taking any supplements at the moment. Looking into adding singly and overall nutrition going forward. I'm sure I'm not optimum. BTW, what percentage through range for fT4 should I be aiming for? Would it be higher than usually recommended due to central hypothyroidism and loss through kidney issue?

[SlowDragon Administrator in reply to Agitator23]

Test folate, ferritin and B12 at least annually

Test vitamin D ideally twice year when supplementing

Test vitamin levels BEFORE starting any supplements

Many (most?) thyroid patients find they need to supplement vitamin D, vitamin B complex and magnesium continuously to maintain good levels

Some initially need separate B12 as well as B complex

Low iron/low ferritin common, especially initially

Come back with new post once you get test results

[SlowDragon Administrator in reply to Agitator23]

what percentage through range for fT4 should I be aiming for?

Typically on just levothyroxine, many people find they need Ft4 at least 60-70% through range (testing 24 hours after last dose levothyroxine)

Your TSH is not reacting to your low Ft4 levels

So it’s going to be especially important to dose by Ft4 and Ft3 levels

Low vitamin levels, especially low ferritin, tend to lower TSH

We need optimal vitamin levels for good conversion of Ft4 to Ft3

[humanbean in reply to Agitator23]

Central hypothyroidism (CH) is caused by either

a) a pituitary which is unable to produce enough TSH (Thyroid Stimulating Hormone) to stimulate the thyroid to produce enough thyroid hormones OR

b) a hypothalamus which is unable to produce enough TRH (Thyrotropin Releasing Hormone) to stimulate the pituitary to produce enough TSH

[Note : Thyrotropin is another word for TSH.]

Secondary hypothyroidism is caused by (a).

Tertiary hypothyroidism is caused by (b).

The name Central Hypothyroidism is used when hypothyroidism is discovered and is caused by either (a) OR (b) but doctors haven't discovered which.

If Central hypothyroidism goes on, unsuspected and untreated, for a long time the thyroid may become atrophied through lack of stimulation. If the patient's small thyroid is eventually discovered it is possible that doctors will attribute the problem to Hashi's or Ord's or a birth defect which caused the patient to have a small thyroid. A pituitary or hypothalamus problem is still likely to be dismissed as a cause of hypothyroidism because doctors get taught that Central Hypothyroidism is very, very rare and can be assumed to be a "zebra" they shouldn't expect to find. The vast majority (about 90%) of people with hypothyroidism are assumed to have autoimmune hypothyroidism aka Primary Hypothyroidism.

Central Hypothyroidism presents with slightly over the range or low in range or below range TSH depending on the severity of the problem. As a result Free T4 and Free T3 are low in range or below range.

Since doctors only look at TSH they may mistakenly diagnose Central Hypothyroidism as hyperthyroidism if TSH is low enough. If they actually looked at TSH, Free T4 and Free T3 together they would be much more likely to recognise hypothyroidism of any flavour.

[sparkly in reply to SlowDragon]

Thanks for sharing that information. I never realised there was a connection with below range GFR and thyroid issues. Mine constantly below range for years but never addressed just flagged on blood tests. Should it be addressed or is it normal gp/ consultants to disregard it?

[SlowDragon Administrator in reply to sparkly]

Correcting low thyroid levels should improve kidney function

[ShiningStar77 in reply to SlowDragon]

thanks so much op for posting this question - I have been having the same issue !

[SlowDragon Administrator]

very very helpful profile 👏👏👏👏👏

Dr/Radiologist was categoric at time of scan that my thyroid is very damaged. From the scan he was very confident that I have autoimmune thyroiditis, which has been going on a long while! I said I was TPO negative. He immediately said 'well the blood test is wrong'.

Finally, after nearly a decade, here is empirical proof of a thyroid-related disease. I wanted to cry.

The Radiologist/Dr said he would recommend to my GP (NHS) I start levothyroxine

yet still it was a battle to prescribed …..shocking.

Sadly not uncommon

have you tested Thyroglobulin antibodies yet?

Significant minority of Hashimoto’s patients only have high TG antibodies (thyroglobulin)

If both antibodies are negative

20% of autoimmune thyroid patients never have high TPO or TG antibodies and ultrasound scan of thyroid can/should help get diagnosis

[Agitator23 in reply to SlowDragon]

No raised antibodies of any type so my ultrasound was crucial for diagnosis!

[B12again in reply to SlowDragon]

I have just been diagnosed with autoimmune thyroiditis. I was hypo for 15yrs and just on 50mg Levo but was never look at for underlying cause. Antibodies were also the cause of my PA, having affected the stomach’s parietal cells. I am now having my Levo increased.

[SlowDragon Administrator in reply to B12again]

Good grief

Left on only 50mcg levothyroxine for 15 years!

Likely to need to increase slowly having been left woefully under medicated all that time

Bloods should be retested 6-8 weeks after each dose change or brand change in levothyroxine

For full Thyroid evaluation you need TSH, FT4 and FT3 tested

Very important to test vitamin D, folate, ferritin and B12 at least once year minimum

what vitamin supplements are you taking

[B12again in reply to SlowDragon]

Thanks Slowdragon. I’m in a much better place now. I SI B12 EOD, vit D3 and K2 daily, Magnesium 400mg elemental daily, gentle iron daily, folate 5mg weekly after a period of daily. Stopped B complex. My diagnosis came after through a recent consultation with Doctor Klein who also advised on vitamins and recommended testing period. I had been on most anyway.

[Tussa]

I went through the same thing and I was so worried. But after getting my levels back to normal and mainly by adding T3 my GFR went back to normal as well.

[Dolphin75]

I’m under going tests and investigation at the moment as for the past year for high TSH it’s currently at 40 but was as high as 139 and I’m on 225mcg thyroxine. I’ve had some blood tests one of them is called Glomerular filtration rate when I’ve looked at what this is it’s to do with Kidney function. Mine is at 66 which puts me in the mild loss of kidney function and if I drop under 60 I go into the mild to moderate group.

[Agitator23 in reply to Dolphin75]

Have they linked your hypothyroidism to your kidney issue? My friend, who's hypothyroid, was told the decline in function over the years was down to ageing... There is a well-documented link between hypothyroidism and kidney function, however. Are you losing albumin in your urine? Did they do a urine analysis?

I'm going to put kidney function front and centre in my next consultation about hypothyroidism. Hopefully, they will see proper dosage and management of the hypothyroidism is crucial to my kidney health.

[Dolphin75 in reply to Agitator23]

No they haven’t said anything the test was done it June at the hospital I’ve asked for a copy of the results which I just received last week an I've not seen anyone since I had a urine test at the beginning of the year but nothing since. I’m due a blood test this week to check my iron levels so will mention to the doctor then .

[SlowDragon Administrator in reply to Dolphin75]

Dolphin75

Get FULL thyroid and vitamin testing

Bloods should be retested 6-8 weeks after each dose change or brand change in levothyroxine

For full Thyroid evaluation you need TSH, FT4 and FT3 tested

Also both TPO and TG thyroid antibodies tested at least once to see if your hypothyroidism is autoimmune

Very important to test vitamin D, folate, ferritin and B12 at least once year minimum

Low vitamin levels are extremely common when hypothyroid, especially with autoimmune thyroid disease

About 90% of primary hypothyroidism is autoimmune thyroid disease, usually diagnosed by high TPO and/or high TG thyroid antibodies

Recommended that all thyroid blood tests early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

How much levothyroxine are you taking and which brand

What vitamin supplements are you taking

[Hidden]

And what's your T3 level?

[Dolphin75 in reply to Hidden]

T3 is 3.9

[Hidden in reply to Dolphin75]

It's too low, you need at least 5.2

[Dolphin75 in reply to Hidden]

Oh really thanks for this the results of the blood test or what they should be have not been mentioned yet but the test was 6 weeks ago.

[Agitator23 in reply to Hidden]

My latest was 5.1. It's always been upper 4s or around 5.

[EMBoy]

Yes, reduced renal function and hypothyroidism are linked. When I was first diagnosed (about 15 years ago), my eGFR was reduced and my serum creatinine was raised. I wasn't tested for albuminuria, but the other two gradually returned to normal. In those days, a routine thyroid function test also included a renal function test, but I haven't had my renal function tested for many years. I just assume that it's still normal.

Although reduced kidney function and hypothyroidism are linked, there are many other causes of low renal function and albuminuria, so it might be worthwhile trying to get an appointment with a nephrologist, just to be on the safe side.

[Agitator23 in reply to EMBoy]

Thank you for your reply. That's useful information and advice.

[Litatamon]

I have one kidney so I am always on my results.

Before my thyroidectomy, I had dropped 11 points in my eGFR, in less than a year. My ex-GP's reply - Drink more water before the next test 🙄 & 'But it is still good for one kidney!' 🙄. Absurd. I drank the water for her and tested again, another two points down. She was so without any sense of urgency and did not think I should be concerned. I told my gynaecologist, who is an outstanding doctor. He was 'Oh no that much of a drop in under a year needs to be investigated 💯. Not normal.'

Within a few weeks of my thyroidectomy it shot back up instantly. My labs were never that off re:thyroid panel before the thyroidectomy. But something was up as my thyroid was called "completely diseased" by my surgeon. And the pathology supported that, so for those reading doctors often have no clue what is going on inside one's body at times.

And recently the eGFR was at 72, when it had been as low as 58 that year.

So relieved because a lot of the times a drop in eGFR is permanent.

Not one of my doctors knew about the thyroid connection. Researched myself and learned about it here, from these wonderful women and men. We are so lucky to have this forum & platform.

All the best figuring it out OP.