Author Topic: ANA  (Read 1226 times)

One and only

  • Guest
« on: April 21, 2011, 06:11:59 AM »
My readings on the ANA have always been less then 90, I am confused,, I see some here that say less then 640, and some other numbers, I guess what i;m asking is , is 90 some sort of reference number,, and can the test be done with lower numbers, I just dont get it,, it has me stumped,


  • Guest
« Reply #1 on: April 21, 2011, 10:16:16 AM »
It sounds like you had an ANA Direct test, which counts the antibodies as a whole number rather than as a titer.

For a regular ANA test, anything between 1:40 (1 in 40) and 1:160 (1 in 160) is considered a low positive. Above that is high (1:320 +). With the titers, the blood is diluted until the antibodies can't be seen, which is why you might see > 1:640. In that case, there were antibodies after five dilutions, but not after a sixth (the bottom number doubles with each dilution: 1:40, 1:80, 1:160, etc.).

For the ANA Direct, anything under 100 is negative. Anything over 120 is positive. Results in between are "equivocal." Page 3 of this PDF explains in more detail

Your results indicate that you have some antibodies, but that's not abnormal. Many healthy people have these, and they don't necessarily indicate an autoimmune condition. Now, Sjogren's can be seronegative (no abnormal blood test results), so it doesn't rule that out either. Something like lupus, however, would be unlikely, as more than 90% of people with that illness have a positive ANA result.

A low positive ANA can indicate nothing at all or an autoimmune condition like Hashimoto's (AI hypothyroidism) or Sjogren's. A high ANA can be Sjogren's, lupus, or any other number of AI conditions.