Re: Rheumatoid Factor/Numbers?/Scleritis!

[Guest guest]

Jeanne,

I'm so sorry to hear about another scleritis incident. Are you on the

cancellation list for the rheumatologist? Maybe you could give the

office a call and explain that you had another attack and that you are

very concerned about it and would like to be sure that you will be seen

as soon as possible.

RA factor = rheumatoid arthritis factor

RF = rheumatoid factor

I wish the labs would standardize the terminology and measurement of the

dang antibodies, but that's just a dream of mine. The preferred and most

common term for the antibodies in question is RF.

When the value is reported as yours was - 1:80 with a normal of 1:20 or

less, that means they are telling you in terms of dilutions how much RF

is present. You are two dilutions out which isn't way high. Most sources

I've seen refer to an RF of 1:80 as equivocal. But because of the lack

of standardization and since every patient has a unique situation, your

doctor should be the one to decide what it means for you specifically.

How do they come up with these dilution results or titers (or titres)?

It goes something like this: First they diluted your sample 20 times

(1:20), since 1:20 or less is the cutoff for normal, and they could

indeed detect the RF in your diluted serum. Then they took it to 1:40

and again detected RF. They again diluted, but this time to 1:80 (your

sample diluted 80 times; one part your serum plus 80 parts the dilution

liquid) and still were able to find traces of RF. In the next try, at

1:160, RF could no longer be detected, so they stopped there. In the

end, your result is reported as 1:80 since that was the last dilution of

the series where RF could be detected.

As you can see, the titer patterns here would be 1:20, 1:40, 1:80,

1:160, 1:320, 1:640, 1:1280, and so on - they double the test liquid

each time. The more RF in your sample, the more dilutions the lab has to

perform, and the higher that last number in the ratio will be. If this

makes no sense to you, let me know, and I will try to explain it in a

different way.

RF can be positive for many, many reasons and positive levels are found

in seemingly healthy people, especially with increasing age. RF is in no

way specific to rheumatoid arthritis, although a very high level would

lead your physician to strongly suspect RA. On the other hand, about

25 - 30% of RA patients never test positive for RF.

So, RF results can be a good clue for your physician, but,

unfortunately, the test has limited value. Your clinical picture is much

more valuable in helping to establish your diagnosis.

Some links on RF:

http://www.fpnotebook.com/RHE56.htm

http://www.nlm.nih.gov/medlineplus/ency/article/003548.htm

http://www.labcorp.com/datasets/labcorp/html/chapter/mono/se024700.htm

http://www.medmedia.com/oo3/122.htm

By the way, thanks for uploading that great picture of you, your

husband, and children at the beach - what a beautiful family!

Hope you can feel better soon,

[ ] Rheumatoid Factor/Numbers?/Scleritis!

> Hi Guys!

> My first blood screen revealed a positive Rheumatoid Factor. It was

> called " RA " on the lab sheet. What does the " A " in RA stand for--

> anticoagulant? I've always seen it as RF? Anyways, I had a positive

> RA with a titre of 1:80. Although it was high in comparison to the

> the lab's normal <1:20, how high does this number get in very active

> rheumatic disease? Can it be present in other conditions outside

> autoimmune? What were your presenting titres when symptoms started? I

> got another scleritis attack on Saturday!! I'm back on the pred forte

> drops and can't start systemic drug therapy for it until I get that

> initial work-up from my Rheumy--first visit's still a month away!

> UGH! Catch 22, I swear! Sorry, had to vent. Thanks for listening!

> This rainy weather is killing me!!! Ouch!

>

> Hope it's a pain free day!

> Jeanne in Ohio