Discussion in 'Diagnostic Guidelines and Laboratory Testing' started by Uno, Apr 26, 2016.
Hi - I'm in the UK, where may I get low NK cell
Function tests and other lymphocytes done?
I don't think there are any NHS labs doing NK cell function in the UK - basically because nobody knows what it means and so there isn't much point. You might find a private lab that does but I would very much doubt the results could be trusted. NK cell assays are very tedious and a good immunologist is not going to sit in a private lab doing tests that nobody knows what to make of. I suspect there are labs in Europe that do NK function but I also suspect they tend to be the sorts of labs that will sell you whatever result you want to get. I would not waste money on it. NK function is of research interest on a population basis but I do not think it means anything to individuals.
Other lymphocyte populations are chiefly studied just as counts in blood. Again, they do not tend to mean much unless there is some other disease present like AIDS or leukaemia. NHS labs routinely do lymphocyte subsets but only if there is a good reason to. Again, there are probably European labs that will do them for a fee, but I am not sure what you would do with the result. As far as we know so far lymphocyte subset differences have no implications for how to manage ME in an individual case and it is not clear that they are different from normal anyway. Research groups in the UK are actively looking at lymphocyte subsets but in a very basic way trying to understand the disease, not in terms of individual treatment.
Nevertheless, so many pwME report out-of-range values for their NK cell function labs.
The fact that there is a range seems relevant; I should think by definition most healthy people fall within that range, but maybe not. The stream of reports of out-of-range values for NK also seems relevant.
As more research is performed, we may learn more about the association.
Yes, the question is whether these out of range results actually indicate something different about PWME or just logistics. As I understand it, time of day, lying in bed for a week or drinking a cup of coffee can affect NK function results. There was a lot of excitement about them in the 1980s but then researchers found they were too inconsistent to be helpful. I would bet that the labs that report NK function are only too happy to sell people low results, to keep the test popular. Within the research community we still seem to be in a situation where there is no agreement what PWME as a group show.
Yet still there is an operational range. I would hope that was appropriately established. If a given population repeatedly tests outside of it, that may speak to something a wee bit more significant than a morning cup of coffee.
More research would be welcome.
As far as I know there is no agreed reference range of the sort one would have for a diagnostic test since this is still a research tool. An important issue is that the standard K562 killing assay really only tests the tendency of NK cells to kill cells failing to express MHC Class I. That is only one way NK cells can kill. They can also use CD16 to perform antibody dependent cytotoxicity. And whether they kill or not may have a lot to do with whether or not they have been primed by cytokines.
There are plans to try to replicate and get consensus on these issues using population based cohorts with controls whose blood has been collected in exactly the same way. It all takes time but hopefully there will be some consensus reasonably soon.
As has been mentioned, there isn't really any good reason to take such as test, especially since they are quite expensive.
Whatever your result, it will not help in deciding on a course of treatment, and it is not going to provide anything definitive in terms of a diagnosis of ME/CFS. I can think of a lot more useful tests to spend my money on, such as viral testing. Was there any reason you wanted to take this test?
But for your info, there are apparently a couple of labs in Germany that do NK cell function testing (not to be confused with the NK cell count testing). See this post.
As an aside, I recently learnt that NK cell count (CD57 count) can be used to help diagnose Lyme disease. So it seems that in ME/CFS, NK cell function can be low, and in Lyme, NK count can be low.
I was wondering whether an NK cell count test (which I think is relatively cheap) might be useful as a differential diagnosis between Lyme and ME/CFS. Though I have never seen any research or heard of any doctor using such a differential diagnosis, probably because the idea has never been properly validated.
I was told that in 2012 my immunity was at 74%. I need to know if this has gotten worse. My GP believes me and it just reassures me that I am sick. I keep getting infections in my bile ducts like every month and nobody knows what to do with me or what to test me for. I've already tested + for HHV6 and EBV.
I don't know what to do am so weak with infection.
Jonathan Edwards the lab said I had immunosuppression so what should I test for now - I cant go bk to s africa.
Was that specifically in relation to your NK cells? Or does this immunosuppression relate to some other part of your immune system (like IgG deficiency, for example)?
@Hip, cd57 values can be influenced by more than just Lyme. So the answer to your question of whether cd57 can be used to distinguish Lyme from ME/CFS would likely be "No".
I appreciate that low CD57 is not exclusive to Lyme, so there would not be 100% certainty in using CD57 as a Lyme—ME/CFS differential diagnosis; but if validated, it might be a helpful differential in a probabilistic way.
You mean validated for Lyme? Lots of push-back against CD57 as a marker by mainstreet interests.
Regardless, I would guess most clinicians knowledgeable about Lyme employ it in the States.
Try labs that deal with infertility and ivf for a nk test. If you do a search online you should find a few in the uk. Good luck.
You can also try a Google Site Search
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