Rheumatoid Arthritis Diagnosis

If a patient is showing early signs and symptoms of rheumatoid arthritis, a doctor can refer the patient to a rheumatologist – a physician who specializes in rheumatic diseases. The rheumatologist will work with the patient and the patient’s primary care physician to reach a rheumatoid arthritis diagnosis and provide treatment.

Because there is no exact known cause of rheumatoid arthritis, doctors look at a number of different factors before reaching a diagnosis. To reach a diagnosis, physicians follow a set procedure looking for multiple criteria, rather than one individual test. This includes examining physical symptoms, looking at family and medical history, and performing blood and other diagnostic tests.

Some cases may be easier to diagnose than others, especially in the early stages of developing symptoms when symptoms may be less clear. Doctors work hard to ensure they’ve looked at all possibilities and that their examination and testing results are consistent with most cases of rheumatoid arthritis.


To begin the diagnostic process, doctors first look at symptoms. Rheumatoid arthritis has a clear set of early signs and symptoms that lead doctors to consider it as a diagnosis. These initial symptoms include:

  • Joint pain, stiffness and swelling for more than 6 weeks
  • Swelling affecting 3-4 different joints or more
  • Morning stiffness lasting longer than 30 minutes
  • Symmetrical symptoms affecting both the left and ride sides of the body
  • Swelling and pain affecting the wrists, hands and finger joints
  • Rheumatoid nodules developing under the skin

If these symptoms have been a concern for more than six consecutive weeks, doctors may consider these as symptoms specific to rheumatoid arthritis as opposed to other types of arthritis, like osteoarthritis.

Doctors may also look for and ask about symptoms like fatigue, low-grade fever, loss of appetite, and even feelings of depression and malaise.

A full physical examination helps doctors find these symptoms and look at joints for tenderness, swelling, soreness, warmth, and redness. They ask about difficulties moving joints and decreases in range of motion.

Symptoms may come and go but typically, they do not. They remain noticeable and possibly progressive.

Medical & Family History

The patient’s medical history and family history are important factors in helping to reach a rheumatoid arthritis diagnosis. Studies have shown that the average risk of someone in the general population developing rheumatoid arthritis is about 1%. However, if there is a family history of the disease, the risk of another family member developing rheumatoid arthritis increases. Therefore, genetics are a contributing factor in addition to other factors.

When diagnosing rheumatoid arthritis doctors ask about the following:

  • Patient’s family members who have or had rheumatoid arthritis
  • Patient’s existing or past autoimmune disorders
  • Patient’s family members with other autoimmune disorders
  • Other medical conditions, illnesses or complications

Depending on each patient’s unique set of answers, it can help doctors identify factors that lead to a rheumatoid arthritis diagnosis.

Blood Tests

One of the most important and helpful criteria in reaching a rheumatoid arthritis diagnosis is the blood test to identify a specific set of antibodies that are known triggers of rheumatoid arthritis symptoms. There are multiple blood tests that can be performed in the diagnosis process. These tests include:

  • Rheumatoid factor
  • Cyclic Citrullinated Peptide (CCP)
  • Erythrocyte Sedimentation Rate (ESR) and C-Reactive Protein (CRP)

Rheumatoid Factor

Rheumatoid factor is a type of antibody found in the majority of rheumatoid arthritis patients. If a patient tests positive for rheumatoid factor it helps to reach a diagnosis, but its presence doesn’t confirm it.

Many patients with other autoimmune disorders and inflammatory conditions test positive for rheumatoid factor but don’t have rheumatoid arthritis.


Because rheumatoid factor isn’t a guarantee of developing rheumatoid arthritis, doctors now test for the presence of another antibody, anti-CCP. If a patient tests positive for anti-CCP this is a strong indicator of rheumatoid arthritis. However, the anti-CCP antibodies can exist in a person’s system long before they ever exhibit symptoms of rheumatoid arthritis.


ESR and CRP are tests that doctors use to measure the level of inflammation in a patient’s joints. If a person indicates a certain level of inflammation and exhibits symptoms of rheumatoid arthritis, this becomes another very strong indicator of a possible rheumatoid arthritis diagnosis.

Imaging Scans

When a patient has strong and clear symptoms of rheumatoid arthritis, a doctor may also order a series of imaging scans. These include x-rays, MRI’s, and possibly ultrasounds. In these imaging scans, doctors look for signs of joint damage. Bone and cartilage erosion as well as narrowing joint spaces can be signs of rheumatoid arthritis patterns.

Reaching a Rheumatoid Arthritis Diagnosis

Once all of these steps have been conducted, doctors will look at everything and reach a conclusion based on overall results. Some doctors take a more symptom-based approach to diagnosing rheumatoid arthritis while others use blood tests and medical history to confirm a rheumatoid arthritis diagnosis.

This is why it’s possible to be diagnosed with rheumatoid arthritis but not test positive for antibodies or have a medical history of rheumatoid arthritis in your family. If the symptoms themselves are consistent with rheumatoid arthritis, then it can still be diagnosed.

In this case, there are generally two classifications of rheumatoid arthritis. However, the main criteria for diagnosing rheumatoid arthritis must include the persistent demonstration of symptoms for greater than six weeks, symmetrical symptoms, as well as multiple joints affected including fingers and hands.

Classifying Rheumatoid Arthritis Diagnoses

If a patient displays all the symptoms of rheumatoid arthritis and tests positive for antibodies then they can be diagnosed with seropositive rheumatoid arthritis.

However, if a patient displays all the symptoms of rheumatoid arthritis, but doesn’t test positive for antibodies, the doctors can make a seronegative rheumatoid arthritis diagnosis.

Read more about the types of rheumatoid arthritis here.

Other Factors

Rheumatoid arthritis symptoms can be mistaken for other conditions. Doctors work to rule out the potential of other illnesses when they are first alerted to possible signs of rheumatoid arthritis. Once these conditions have been ruled out, it makes it clearer to reach a rheumatoid arthritis diagnosis. Some of these conditions include:

  • Several other forms of arthritis including osteoarthritis
  • Lupus
  • Lyme disease
  • Gout
  • Fibromyalgia
  • Still’s disease

Due to the ambiguous nature of many rheumatoid arthritis diagnoses, researchers are continually looking for links and similarities between disease symptoms and patients’ genetics and medical histories. While diagnosing rheumatoid arthritis is difficult and can be complicated, the most important thing is to detect symptoms early and begin treatment as soon as possible.