pHPT and normal PTH values

Can't believe this paper was published nearly 12 years ago and STILL endos are not taking note!

Jasmine x

http://www.ncbi.nlm.nih.gov/pubmed/10873186

Hi Jasmine great link.
There is no excuse for them not knowing this other than just not being interested enough to research it. Surely they can do the research as well as we can !!!!!!
Amanda xxxx

Thanks Jasmine, I think we will add this to the reference section as it could be useful  ammunition if Endos are being difficult ! 

Nelly

It doesn't surprise me, Jasmine. It seems to me that the doctors just don't WANT to learn! As I mentioned before, my ionized calcium was never elevated during the entire time I had HPT. Even after having 2 tumors removed from my neck, my endo STILL does not get it. At my first followup appointment after surgery, she looked at my labs and said, "Well, it looks like you're been cured. Your ionized calcium is normal." ???????

I don't know why it's so hard for them to learn that the calcium and/or the PTH can be in the normal range with HPT. It's so simple. If the PTH is inappropriately high for the calcium level, the person has HPT. How hard is that? When 1 is high, the other should be low. If they are both near the upper end of normal, there is still a problem. If we can read something that tells us this, and we can learn this, why can't they?! I just don't get it!

Audrey

Audrey

Just a comment about this, when the Calcium is elevated how low should the PTH be if they are working correctly? Also, when the Calcium is low normal, what should PTH be?

Thanks

Well, Lucie, it would depend on how high the calcium is elevated. I guess the easiest way to explain this would be to post all of my lab results . I don't have time to do that right now, but I would be happy to do that for you soon. I would like to say that immediately before my parathyroid surgery, my calcium was 10.2, which is not considered high. However, my PTH was 62.5, indicating that my body was trying to raise my calcium level. At 10.2 (2.6 in UK numbers), my body should not have been wanting more calcium in the blood. My first labs after surgery revealed a calcium still of 10.2, but this time the PTH was 26.8, indicating my body was happy with that calcium level. My latest labs revealed a calcium of 9.9 (which would be rounded off to 2.5 in UK numbers) and a PTH of 42.0. That is still good. Before surgery I had a calcium of 9.8 , which would normally be ok, but my PTH was 112.0, which is way too high for that level. It is hard to give exact numbers. I will post all of my levels for you soon. I have a lot of them. That might be of help to you.

Audrey

Thanks Audrey. Just trying to understand levels etc if you have an inconsistent level of blood tests, would this be abnormal? I only ask as I get confused by Consultants and GP's! HPTH wasn't ruled out from my Jan blood test and I had an high level of Calcium in my urine in May, so I get confused as to whether it's only HPTH that can make your levels inconsistent or another health issue   

Sorry to add into this post!

I know it can be confusing, Lucie, and you should never feel bad asking questions.  We're all here to learn from each other.   And, if I'm not mistaken, I think it is still possible to have HPT with levels that look normal, if the urine calcium is elevated.   I would have to do some more research on this.    Maybe your case is one of the tougher ones.    

As I mentioned before, mine was a tough case to diagnose because my urine calcium was always normal, my ionized calcium was always normal, and my albumin and phosphorus levels were such that they did not help to diagnose me either.  I never had kidney stones, and I never had osteoporosis or even osteopenia.   The only things I had to go on were a very long list of symptoms and PTH levels that were always too high for my calcium levels, but I knew I had HPT the very first time my PTH level was tested.    It seemed very simple to me, but it sure wasn't to my doctors!    

I will get my levels posted soon.

Audrey

Hi Lucie,

Not sure if you are talking about calcium or PTH.

In the case of calcium, on a daily basis, in normal individuals it should stay in a tight range. It should be incredibly stable. Your body wants to keep it very tightly fixed. It does vary very slightly throughout the day (and month if you are a lady and have periods) but we're talking something like 0.1mmol/L.

PTH on the other hand, is constantly adjusted by your body. It doesn't last long in the blood (10mins?) so your parathyroids constantly churn out more depending on what you need. It is increased when you're losing calcium and reduced when you're gaining calcium. The level at which it stops raising your calcium is not the mid point of the range (common doctor error). More like 25% BUT your vitamin D status affects this switch point.

I previously posted a formula in the 'HPT or not HPT' thread which was developed by some researchers to calculate your personal max PTH level for a given calcium and vitamin D. Try it out and see if your PTH levels are higher that what the formula says should be your max value.

There are lots of other factors that can have an effect on PTH results. Research suggests it changes depending on the time of day, peaking around 2am and 2pm on average and being lowest between 8-10am (when my surgery does bloods!). Your glands give out 1-7 pulses every hour which are about 0.5-1.8pmol/L each. It's higher in winter and lower in summer by maybe on average 1pmol/L, thought to be due to vitamin D status. On average, it's higher in men and vegetarians.

Also, it's massively unstable outside of the body and therefore test results are somewhat flaky (although important to note, it only goes decreases once it's out of the body so you are only going to get a lower than actual result. If your result is high, it really was high.) Test result differences can be as much as threefold, which explains why some people get very different results at different hospitals. 

So in summary, normal people with steady vitamin D levels have steady calcium, and PTH which fluctuates (but doesn't get ridiculously high).

If you can understand the above you know far more than your doctors. It's a shame there isn't some sort of qualification in PTH studies because I feel like I've spend the last six months revising for it!

Hope that's some help,

Love 
Dee

Thanks for that Dr Dee! It's a pity the Drs and Endos don't know as much as you. Very interesting details and I feel I understand a bit more now. 

Love 
Brigitte xx

Thanks Brigitte,

I've been thinking about an analogy for a while now...

If you think of a lake. Some water will be lost (evaporates or is soaked away) but water is also added (rain).

So the level of the lake represents blood calcium levels and the amount of rain represents the PTH level. So it might rain really hard for a bit and then not rain, then rain some more so the rain varies a lot but the level of the lake only varies a little. The system balances out.

However, in extreme circumstances, if the rain is torrential and unrelenting then the level of the lake is going to keep increasing and eventually flood. Hyperparathyroidism leading to hypercalcaemia.

Might need a bit more refinement to explain the effect of vitamin D... more thinking required. But hopefully a useful way to explain blood results to friends and family. I know I struggle.

Love
Dee
xxx

Great thinking, Dee - that is most useful - could look good on a poster for GP's and endo's!

Love from Tigerlily xxxx