Author Topic: Please Help Titre to IU conversion for Rheumatoid Factor  (Read 5393 times)

Fulham205

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Please Help Titre to IU conversion for Rheumatoid Factor
« on: June 14, 2010, 02:13:34 AM »

Hi Friends,

i hope you are all feeling well today.

As you may know i am new to all this and i need some help. Over the weekend i had to do some more blood tests in prepartation for my appointment next week.

Anyway, i got a Rheumatoid Factor result back this morning and i am really confused (again  :D)

Previously all my RF results were given in IU this time i got them as a Titre score of 1:16, now i originally thought that was good my last RF result was
128 IU/ml so i thought a lot lower yippeeeee

But just now i did some looking on line and i found something that might suggest 1:16 is actually high when converted to the IU/ml scale.

Can anyone please shed some light on all this, please please how do you convert it or does anyone know what 1:16 means

And for all those football (soccer fans) on here anyone see the England USA game. i am english so the result did nothing for my mood hahahahahahaha

Thanks in advance to anyone who takes the time to reply

Fulham205













Linda196

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Re: Please Help Titre to IU conversion for Rheumatoid Factor
« Reply #1 on: June 14, 2010, 03:49:42 AM »
Fulham, is there a possibility that the titer is 1:160? Most agglutination testing result starts at a value of 1:40, and progress by repeated dilution by half, so the next result would be 1:80, then 1:160, 1:320, and so on.

It's very difficult to find an actual conversion table for nephelometric (IU) to agglutination (titer) values, but normal ranges seem to indicate that 60 IU is roughly equal to 1:80 titer, and mathematically, that would make 128 roughly equivalent to 1:160 (remember that the IU can change by a value of one, while the titer has to progress by doubling the second number so there are no "in between" values with titer).

Generally a titer of 1:80 is considered normal or "non-reactive", and 1:160 and up is considered significant. There doesn't seem to be much of a corelation between high RF and severity of symptoms with Sjogrens, but with Rheumatoid Arthritis, higher titers can be indicators of the degree of joint damage potential.
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Autoimmunity

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Re: Please Help Titre to IU conversion for Rheumatoid Factor
« Reply #2 on: June 14, 2010, 06:26:39 PM »
Fulham, is there a possibility that the titer is 1:160? Most agglutination testing result starts at a value of 1:40, and progress by repeated dilution by half, so the next result would be 1:80, then 1:160, 1:320, and so on.

It's very difficult to find an actual conversion table for nephelometric (IU) to agglutination (titer) values, but normal ranges seem to indicate that 60 IU is roughly equal to 1:80 titer, and mathematically, that would make 128 roughly equivalent to 1:160 (remember that the IU can change by a value of one, while the titer has to progress by doubling the second number so there are no "in between" values with titer).

Generally a titer of 1:80 is considered normal or "non-reactive", and 1:160 and up is considered significant. There doesn't seem to be much of a corelation between high RF and severity of symptoms with Sjogrens, but with Rheumatoid Arthritis, higher titers can be indicators of the degree of joint damage potential.

CONFUSED...

My titer is positive at 1:64 which it states is Abnormal.  Now I am confused exactly what that means???