Rheumatoid arthritis (RA) can be a serious and lifelong disease. The information on the internet about rheumatoid arthritis can scare anybody. RA factor is one of the most commonly ordered blood test in somebody with joint pain. The art doesn’t lie in ordering the test, the art lies in to make sense of it. Every day, I see a query on the internet on somebody having a positive rheumatoid factor (RA factor) and fear of having rheumatoid arthritis. Ideally, they should show a rheumatologist and get that answer. This post is for those who like to search things before going to a doctor and a guide on why it is so important to show arthritis specialist.
Most rheumatology tests are not specific. This means that these tests are often positive in normal population. Please show a rheumatologist, because only they are experienced enough to make sense of your symptoms and these tests.
1) A positive RA factor (or rheumatoid factor) alone doesn’t mean that you have Rheumatoid arthritis
A positive test for RA factor is quite common in normal people. Just because it is called RA factor, a positive test doesn’t mean one has rheumatoid arthritis. But you should know what to do if you have one. Your general doctor who ordered the test, most times, is not qualified to make sense of a rheumatology test. It can, at times, create unnecessary panic and confusion.
RA factor is a test. RA or Rheumatoid arthritis is a disease (don’t get confused 🙂 ). RA factor was so named, as it was found first in rheumatoid arthritis (RA) patients. But, low levels of RA factor can be seen in 5-10% of normal population. All tests in medicine need interpretation by respective specialist. Unfortunately, Google is still a long way away from replacing doctors. 🙂
2) When should one be concerned of a positive rheumatoid or RA factor?
Remember, the presence of following factors doesn’t mean that you have some disease. It just means that you should be more concerned about a positive test when these are present. Show a rheumatologist as soon as possible.
- If you have increasing joint pains, swelling or stiffness lasting more than half an hour in mornings. Also if you start having ‘sudden new’ funny symptoms like rashes, ulcers, weakness, etc or off late your body just doesn’t feel right.
- If your ESR and CRP are also high (they are markers of swelling or inflammation).
- If your RA factor levels are very high (at least two-three times lab upper limit. For example, if a laboratory gives normal as 16 units, most rheumatologists will be cautious about interpreting positive result with values less than < 32 units ).
- If you have other immune tests like ANA, Anti CCP, etc also positive.
I cannot list every symptom here. But a rheumatologist will take multiple factors into consideration before reaching a diagnosis.
Most times rheumatology tests are very complex to perform. A lab without the inadequate experience of doing these tests can sometimes give confusing results. A rheumatologist is usually concerned when there is joint swelling or RA factor is at least three times the upper normal limit of given lab.
3) A positive RA factor can be seen in many other diseases besides Rheumatoid arthritis. A patient with RA can also have negative RA factor!
Positive RA factor can be seen in other diseases like lupus, Sjogren syndrome, vasculitis, etc. Also, RA factor can be negative in 20 % of RA patients! This makes it more complicated. That is why, again, it is very important to show a rheumatologist. Some of these other diseases can be more serious than rheumatoid arthritis.
20 % of Rheumatoid arthritis patients can have negative RA factor ! A diagnosis of rheumatoid arthritis (RA) is most times based on whole picture and not just on blood tests. A rheumatologist (or any good doctor) will often match what they hear and see in patients with their tests.
The fact remains that rheumatology diseases are very difficult to diagnose and more difficult to treat. These can be serious diseases. It’s better to show a qualified rheumatologist and get to the bottom of this as soon as possible. Maybe you just have something mild or no disease at all. If you have a rheumatology disease, most times delaying treatment can lead to damage. One might also require much higher medication in the future if treatment is delayed.
Author: Dr Nilesh Nolkha, Rheumatologist
Dr Nilesh Nolkha is a young and dynamic rheumatologist who keeps patients interests at forefront of everything he does.