Guest guest Posted December 1, 2005 Report Share Posted December 1, 2005 It means that many people who test positive for rheumatoid factor don't ever develop rheumatoid arthritis. In other words, the test is not highly specific for the disease. On 12/2/05, M <pkeith@...> wrote: > Hello, > 1. What is meant by this: there is a high rate of false positives with > the Rheumatoid factor test? > > 2. I have read that the Rheum. factor may become positive as the > length of the disease increases. Have you found this to be true? > I think I have had only one early reading. Yes, this is true. sero-negative patients may sero-convert as time goes on. Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 1, 2005 Report Share Posted December 1, 2005 and Group, See http://www.theberries.ns.ca/Archives/FALL2003/rheumatoid_factors.html " Many conditions associated with chronic inflammation are also associated with positive RF (see table). The incidence and titre increase with age. By age 70, up to 14% of individuals are RF positive. RF is not a screening test for rheumatoid arthritis (RA) in patients with musculoskeletal pain without joint swelling. The predictive value of a test for RA depends on the sensitivity and specificity of the test and the pretest probability of RA. The presence of RF in numerous conditions other than RA limits its specificity. Since RF is not present in all patients with RA, the sensitivity of the test is also reduced. In patients with diffuse musculoskeletal pain without joint swelling, the predictive value of the test is approximately 16%. In patients with a high pretest probability of RA: those with symmetric polyarticular joint swelling, the predictive value of RF factor increases to 80%. In patients with rheumatoid arthritis, RF is an important predictor of a poor prognosis. In high titres, it portends increased joint erosion, extraarticular manifestations and greater disability. RFs deposited in tissues are responsible for rheumatoid nodule formation. In RA patients, approximately 70% are RF positive at disease onset and 85 % become positive over the first 2 years. Serum levels of RFs do not change rapidly and cannot be used to follow disease activity. Some Diseases associated with a Positive Rheumatoid Factor Rheumatic Diseases · Rheumatoid arthritis · Sjogren's syndrome · Systemic Lupus Erythematosus · Mixed Cryoglobulinemia Bacterial Infections · Endocarditis · Tuberculosis · Syphilis · Lyme disease · Viral disease · AIDS · Hepatitis C · Infectious mononucleosis · Influenza Lung Diseases · Interstitial Fibrosis · Silicosis · Sarcoidosis Others · Aging · Malignancy · Periodontal disease " Sincerely, Harald At 04:41 PM 12/1/2005 -0600, you wrote: >Hello, > 1. What is meant by this: there is a high rate of false positives > with the Rheumatoid factor test? > > 2. I have read that the Rheum. factor may become positive as the > length of the disease increases. Have you found this to be true? I think > I have had only one early reading. > >Thanks!! >Pat Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 5, 2005 Report Share Posted December 5, 2005 Pat.... It was four years before I tested positive for RA. Even then my RA factor never went higher than 30. My Rheumatologist always said my bloodwork always looked a whole lot better than my joints. Just goes to show each of us is very different. Martha Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 5, 2005 Report Share Posted December 5, 2005 Hi Martha,if you think that is strange you should have seen my tests.My sed rate was 2 and in 4 years never higher than 4,all blod tests were normal and I was dying of SD.Doinf fine now and on a modified version of MP. Lynne MRSROSE2000@... wrote: > Pat.... It was four years before I tested positive for RA. Even then > my RA > factor never went higher than 30. My Rheumatologist always said my > bloodwork > always looked a whole lot better than my joints. Just goes to show > each of > us is very different. Martha > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 5, 2007 Report Share Posted December 5, 2007 Does anyone know what the normal range is for rheumatoid factor? I was just looking over my test results and my RF was 12. It says the normal range is below 13. Is that right? Thanks! ~Krista Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 5, 2007 Report Share Posted December 5, 2007 Hi Krista, I think the reference ranges vary by lab. Go to http://en.wikipedia.org/wiki/Reference_ranges_for_common_blood_tests At the bottom of the page, they have a reference range of 0-20 for RF, meaning, as I understand it, that 95% of the normal population fall within that range. If that's the case, your RF is normal. Love, PH > > Does anyone know what the normal range is for rheumatoid factor? I was > just looking over my test results and my RF was 12. It says the normal > range is below 13. Is that right? > Thanks! > ~Krista > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 6, 2007 Report Share Posted December 6, 2007 Krista, Congrats on seeing the naturpath. That's great. You should bring the test results with you. Have you been doing the foot baths at home? I seen the mini model which has a smaller bucket that I want. > > > > > > > > > > Does anyone know what the normal range is for rheumatoid > > factor? > > > I was > > > > > just looking over my test results and my RF was 12. It says > the > > > normal > > > > > range is below 13. Is that right? > > > > > Thanks! > > > > > ~Krista > > > > > > > > > > > > > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 6, 2007 Report Share Posted December 6, 2007 Steph-Yeah, she told me she wanted to see all of my past test results. So, I printed them all off last night to bring with me. I've done 2 foot baths so far at home. My hubby did one too. His water wasn't NEARLY as gross as mine was! His was that orange color but hardly had anything floating in it....mine on the other hand was FULL of crud! I just sit mine down in the bathtub and sit on the edge of the tub. Makes it a lot easier then dragging it out onto the carpet. I can just dump it right there. I hope you get one for Christmas! ~Krista > > > > > > > > > > > > Does anyone know what the normal range is for rheumatoid > > > factor? > > > > I was > > > > > > just looking over my test results and my RF was 12. It says > > the > > > > normal > > > > > > range is below 13. Is that right? > > > > > > Thanks! > > > > > > ~Krista > > > > > > > > > > > > > > > > > > > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 7, 2007 Report Share Posted December 7, 2007 Thanks for the warning! I'll dump it into the toilet once I get mine! I take a lot of epsom salt baths so I definitely wouldn't want to make myself worse by doing that! Steph > > > > > > > > > > > > > > > > > > Does anyone know what the normal range is for > > rheumatoid > > > > > > factor? > > > > > > > I was > > > > > > > > > just looking over my test results and my RF was 12. > It > > > says > > > > > the > > > > > > > normal > > > > > > > > > range is below 13. Is that right? > > > > > > > > > Thanks! > > > > > > > > > ~Krista > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > > Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 13, 2010 Report Share Posted December 13, 2010 thank you michelle, that would be great because the RF factor is the most confusing thing for me. his peditrician was on of those docs that said " it cant be jra because the tests dont show that " even though he had all signs and symptoms (every single one, like you plucked him right out of text book) thats part of the reason it tool sooooo long to even get to see the specialist in the first place. it was so frusterating. which is why the fact that the test now shows a result of 7 (now that he has already been diagnosed) when previously it was negitive. rheumatoid factor I know that sometimes it is positive and sometimes it isnt I know there are other tests Quote Link to comment Share on other sites More sharing options...
Guest guest Posted December 13, 2010 Report Share Posted December 13, 2010 I think I have some info saved on this that I will try to find and repost. Just a reminder, there is no test to diagnose JA. It is based mostly on symptoms and hands on examination by the dr. Sometimes a child will have an elevated SED rate, or be ANA pos or Rf pos, etc. but none of these are a positive case for diagnosis. That is the most frustrating aspect of diseases of this nature. We can't point to this or that and say the child does not have JA because this is negative. The blood tests done after diagnosis are often to make sure the body is handling the meds well, and to monitor a SED rate. I'll see what info I can find on the Rh factor that may have posted in the past. Michele ( 23, spondy) From: [mailto: ] On Behalf Of michelle_osborne7077 Sent: Friday, December 10, 2010 6:12 PM Subject: rheumatoid factor I know that sometimes it is positive and sometimes it isnt I know there are other tests to diagnos but what I dont understand is what exactly DOES it mean..... originally(before he was diagnosed) they did all the tests and they were all negitive so we went through the whole " the tests dont always show..... but that doesnt mean he DOESNT have JRA " but then after he got diagnosis THEN the next set of tests (11/24/10) showed as rf 7 so i am curious what does that signify since we already decided he has the systemic JRA? , mama to Jordan age5 systemic JRA Quote Link to comment Share on other sites More sharing options...
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