[KarolH]

Inquiring minds want to know and so once again I reach out to all of you for insight in regards to this question.

Is ANA and ANA Assay the same blood test?

I heard that a ANA Assay is by far more accurate then just a ANA yet can not seem to find much information in regards to this by calling upon my friend "Google".

Can anyone here shed some light on this for me please?

 

[Lily]

Hi Karol,

In medical terms an assay just means an analysis done to determine the presence of a substance and the amount of that substance.

There are two different types of assays that can be used, the older method used is the immunofluorescence assay using Hep 2 substrate and there is also one called ELISA assay. ELISA stands for enzyme linked immunosorbent assay (what a mouthful :lol: ) this test comes as a test kit and makes the process more automated.

From all the scientific articles I just looked through it seems that many favour the older method of immunofluorescence over the newer enzyme linked immunosorbent assays. However many also said the accuracy of the immunofluorescence method is only as good as the person doing the testing so that could be a disadvantage in the wrong hands too. I am sure there are fors and againsts in both methods. There was a detailed comparison of the two but it required subscription so I have no idea of the pros and cons of each.

love
Lily

 

[KarolH]

Thanks for your reply Lily.

The information I seem to have stumbled across seems that the assay is more accurate and being used more and more by doctors.

Who knows for sure what is the better, more accurate test. They say for Lupus to go with the assay testing method.

The internet provide a lot of into and yet mixed opinions all at the same time.

 

[Clare.T]

Hello Karol

I am not sure that it matters all that much from the patients point of view since the ANA is but one aspect of diagnosis.

The HEp-2 test has a number of advantages, apparently, but
there may be a wide variability in results between the labs experienced in performing ANA tests, because a lot depends on the lab and the skill of the technicans "analysing the pattern, intensity and even the presence of immunofluorescents". Doctors often prefer one lab over another and one method over another, but we hear most often of the HEp-2 being used.

More recent attempts at improved standardisation have been "introduced using commercially developed enzyme-linked immunoabsorbant assays
( ELISA)............. the results of these tests differ significantly from each other, and in some cases from ANA tested by IFM when tested on the same serum. Those ELISAS with with the highest sensitivity for detection
(in patients known to have the disease) have the highest false positive rate, while those tests with a low false positive rate have a low sensitivity for the detection of lupus in the same patients"
Two other disadvantages of the different ELISA kits that use specific antigens are mentioned, one of which is that they can't "detect as yet unknown cellular antigens" and the conclusion is "that IFM is likely to remain the test of choice using HEp-2 cells for some time"

We hear more frequently these days of the newer ANA direct method.
I am not sure what the advantage of this method is - maybe that it shows up the different antigens/antibodies.

It's all very technical and opinions differ. The main thing is that the old LE test isn't used because it is not reliable. I dont think it is used much at all these days but very occasionally we hear of it and might wonder how up to date a doctor is.

(Quotes From DuBois Chapter 22)

Cheers
Clare

 

[KarolH]

Somehow I have managed to miss your post here Clare.

Thanks for taking the time to explain it.

Happy New Year to you and your family.:wink2: