A Patient Information Guide
Your inflammatory markers and autoimmune blood tests help your medical team detect inflammation in your body and look for signs of autoimmune disease.
These tests are essential tools for diagnosing conditions where the immune system mistakenly attacks healthy tissues, as well as for tracking how well treatments are working.
Normal Range: Less than 5 mg/L
CRP is a protein manufactured rapidly by your liver whenever your body encounters a significant source of inflammation or tissue damage. It is a highly sensitive marker that can skyrocket within hours of an injury or infection.
With ESR (below), this is the most common test used to look for inflammation. Because it reacts so quickly, doctors use it to detect active bacterial infections or flare-ups in conditions like rheumatoid arthritis. Once the infection or inflammation clears up, your CRP level drops back down to normal just as fast.
Normal Range: Less than 20 mm/hr (tends to rise naturally with age)
The ESR test measures how quickly your red blood cells settle to the bottom of a test tube over the course of one hour. When inflammation is present in your body, proteins cause your red blood cells to clump together and become heavier, making them sink much faster.
Unlike CRP, which changes within hours, the ESR is a slower, more deliberate marker that reflects inflammation over days or weeks. It is exceptionally useful for diagnosing and monitoring long-term inflammatory conditions, such as polymyalgia rheumatica (PMR) and temporal arteritis.
Normal Range: 1.50–1.72 mPa.s
Plasma viscosity measures the actual thickness or stickiness of the liquid portion of your blood. Similar to ESR, when your immune system is highly active, it pumps inflammatory proteins into your bloodstream, making the plasma more viscous.
Many clinical teams prefer PV over ESR because it is highly reliable and is not influenced by factors like anaemia, red blood cell shape, or gender. A raised PV indicates systemic inflammation, and tracking it helps your doctor see if a chronic autoimmune condition is responding well to treatment.
Normal Range: Negative (reported as a ratio or titre, e.g., less than 1:80)
An ANA test looks for specialized proteins called autoantibodies that mistakenly target the nucleus (the control center) of your own healthy cells.
A positive ANA test means your immune system is producing these autoantibodies, which is a classic hallmark of autoimmune diseases like Systemic Lupus Erythematosus (SLE).
However, a positive result does not automatically mean you are sick; a small percentage of perfectly healthy people can have a positive ANA, so your doctor will always interpret this test alongside your actual symptoms.
Normal Range: Less than 10 IU/mL (depends heavily on the lab assay)
Anti-dsDNA is a highly specific type of antinuclear antibody that targets the actual DNA structure inside your cells.
While a general ANA test can be positive in many different conditions, a strongly positive anti-dsDNA test is highly specific to Systemic Lupus Erythematosus (SLE). Your clinical team will use this test to confirm a lupus diagnosis. Furthermore, because anti-dsDNA levels fluctuate in tandem with disease activity, doctors track this number regularly to look for or predict active lupus kidney flare-ups (lupus nephritis).
Normal Range: C3: 0.75–1.65 g/L; C4: 0.14–0.54 g/L
The complement system is a group of proteins circulating in your blood that help your immune system destroy bacteria and clear away damaged cells. C3 and C4 are the two most frequently measured components.
During an active autoimmune flare-up—especially in conditions like lupus or specific forms of kidney inflammation (vasculitis or glomerulonephritis)—these proteins become completely consumed as they mistakenly attack your body’s own tissues. Therefore, finding low C3 and C4 levels in your blood indicates to your specialist that an autoimmune process is actively burning through your immune reserves.
Normal Range: IgG: 6.0–16.0 g/L; IgA: 0.8–4.0 g/L; IgM: 0.4–2.5 g/L
Immunoglobulins are the antibodies your white blood cells manufacture to protect you from infections. This panel measures the three primary classes: IgG (long-term immunity), IgA (lining the gut and airways), and IgM (early response to threats).
Abnormally high levels can indicate a chronic immune system overreaction, such as autoimmune hepatitis or a bone marrow disorder. Conversely, very low levels mean your body lacks the essential tools to fight off pathogens, which can happen with certain immune diseases or as a side effect of powerful immunosuppressive treatments.
Normal Range: Negative
If your ANA test comes back positive, your specialist will often order an ENA panel as a follow-up test. This panel breaks things down further to see exactly which specific nuclear proteins your immune system is targeting (such as Anti-Ro, Anti-La, or Anti-Smith).
The ENA screen acts like a magnifying glass. It helps doctors pinpoint a specific autoimmune diagnosis. For example, finding Anti-Ro and Anti-La antibodies strongly points toward Sjögren’s syndrome, while finding Anti-Smith antibodies is highly specific to Lupus.
Normal Range: Less than 14 IU/mL
Rheumatoid Factor is an antibody that attaches to other proteins in your blood and can cause inflammation in your joints and blood vessels.
This test is primarily used when a patient presents with painful, swollen, or stiff joints. While a high RF level is found in the majority of people with rheumatoid arthritis, it can also appear in other autoimmune conditions or chronic infections. Because of this, a positive result must be evaluated alongside your physical joint examinations.
Normal Range: Less than 20 U/mL
Anti-CCP is a highly specific antibody test that looks for immune proteins that attack citrullinated proteins, which are frequently found inside inflamed joints.
This test is a major advancement in diagnosing joint disease. While the Rheumatoid Factor test can sometimes be positive in other illnesses, a positive Anti-CCP test is extremely specific to rheumatoid arthritis. Catching a positive Anti-CCP early allows specialists to start protective joint treatments years before any physical joint damage can occur.
Normal Range: Negative
ANCA are autoantibodies that mistakenly target the internal proteins found inside your white blood cells (neutrophils). This attack causes the white blood cells to inflame the walls of your blood vessels, a condition known as vasculitis.
An ANCA test is crucial for diagnosing rare but serious conditions like Granulomatosis with Polyangiitis (GPA). Because vasculitis can rapidly impact vital organs like your lungs and kidneys, a positive ANCA test helps your specialist team initiate powerful, organ-saving treatments without delay.
Typical Sign: Morning stiffness lasting greater than 30 minutes
While checking your physical joints is not a laboratory blood test, your medical team will explicitly measure the duration of your joint stiffness at every consultation because it directly mirrors your internal inflammation.
Why Joint Tracking Matters: Inflammatory joint conditions cause fluid and inflammatory chemicals to pool inside your joints while you rest overnight. If your morning joint stiffness lasts for more than 30 minutes after getting out of bed, it suggests an active inflammatory process like rheumatoid arthritis. If the stiffness passes within a few minutes, it is more likely to be degenerative wear-and-tear (osteoarthritis), which will not show up on your autoimmune blood screens.
Your monitoring schedule depends on whether you are trying to find an initial diagnosis or managing a long-term condition:
| Clinical Situation | Recommended Monitoring Frequency |
| Investigating New Joint Pains or Severe Fatigue | Once as an initial diagnostic screening panel |
| Experiencing a Symptom Flare-Up | Immediately, to check if CRP or PV levels are rising |
| Stable on Immunosuppressive Medications | Every 1 to 3 months (primarily to check drug safety) |
| Long-Term Monitoring of Autoimmune Disease | Every 3 to 6 months, to track baseline inflammation |
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