As a rheumatologist, I appreciate my primary care colleagues. PCPs are the first line for everything from elevated blood pressure check to double vision to "weird" rashes. I know this keep your plates full.

However, there is one test that I received consultation frequently for: the ANA (antinuclear antibody).

ANA is NOT a Screening Test

ANA is not a general screen for fatigue, tingling, or brain fog. Up to 1 in 5 healthy adults can have a positive ANA. Most will never develop lupus or another autoimmune disease.

When ANA is used in the wrong setting:

• Patients maybe told that they have lupus, creating unnecessary fear.

• Patients get referred to rheumatology before the right work-up is done (ophthalmology for diplopia, GI for dysphagia, neurology for tingling, pulmonology for shortness of breath).

• When rheumatology clinics are filled with "positive ANA" consult, this slows down timely access to care for patients who truly need urgent evaluation for rheumatic autoimmune disease.

ANA Titer Matters

One thing to note with positive ANA is that not all positives are the same.

• Low titers (1:40, 1:80) are common in healthy people and usually not concerning.

• Higher titers (≥1:160) are more likely linked to autoimmune disease, but only when symptoms and other labs point in that direction.

When ANA is Helpful

Order ANA if there are clinical red flags:

• Inflammatory arthritis (joint swelling, morning stiffness)

• Persistent rash with concerning features (malar, photosensitive, discoid)

• Unexplained and persistent cytopenias (low cell count)

• Proteinuria/hematuria with systemic features (frothy urine)

• Raynaud’s with systemic findings (not by itself)

When ANA is not Helpful

Skip ANA for:

• Isolated fatigue

• Fibromyalgia or widespread pain

• Tingling/numbness without neuro work-up

• Nonspecific rash already seen by dermatology

• Mild ESR/CRP bump with no exam findings

A Quick Script for Patients

One of the hardest parts is what patients are told after a positive ANA.

I have clinic visits where patients started crying because they thought they have Lupus.

I think a simple script can be helpful and this is what I typically use in the clinic to explain the ANA.

“A positive ANA is common, even in healthy people. By itself, it doesn’t mean lupus or another autoimmune disease. Low results are especially common. We’ll focus on your symptoms and explore further to understand what’s going on.”

This helps reassure patients without dismissing their symptoms.

In Closing

Autoimmune diseases are real, serious, and sometimes can be tricky to diagnose but they don’t appear out of thin air. They almost always leave signs of inflammation.

Judicious ordering of ANA test, and interpreting titers in context, protects patients from worry and ensures those who truly need rheumatology get timely access.

For Patients:

If you’ve been told you have a “positive ANA,” don’t panic (or Google too much). This test itself does not mean you have lupus or another autoimmune disease. Many healthy people have a positive ANA without ever developing autoimmune disease. Let's investigate further in the context of your symptoms and other blood work.