Gabriela Cobos, MD highlights her lecture Connective Tissue Disease on Friday, November 4, 2022 at the PA/NP Elevate-Derm Conference in Tucson, Arizona

In this video

Dr. Cobos tackles one of the most common misconceptions she sees: that a positive ANA equals lupus. As she puts it, "positive ANA by itself does not give you a diagnosis of anything" — you need additional clinical and physical exam findings to point in the right direction. She uses fatigue and hair loss as examples of nonspecific complaints that shouldn't automatically trigger an ANA. Since "we're all tired," fatigue isn't even in the classification criteria, and reflex-testing every patient with a bit more shedding isn't warranted unless the skin or scalp exam raises suspicion for something like discoid lupus.

She also stresses that results must be put into context. The ANA is a very sensitive test with roughly a 30% false-positive rate at a titer of 1:40 in healthy populations, so the false-positive rate drops as the titer climbs. For a patient who has a positive ANA and even a positive double-stranded DNA but doesn't meet criteria for a specific disease, Dr. Cobos labels the diagnosis simply as "positive ANA" and follows her longitudinally — checking serologies, urine, and labs every six months alongside rheumatology to catch anything that may develop over time.

  • A positive ANA is not a diagnosis — it requires additional clinical and physical exam findings before pointing toward a connective tissue disease.
  • Don't reflex-order an ANA for nonspecific symptoms like fatigue or mild hair shedding unless the exam or review of systems drives suspicion.
  • The ANA is highly sensitive, with about a 30% false-positive rate at a 1:40 titer in healthy people; the higher the titer, the lower the false-positive rate.
  • A patient with a positive ANA who doesn't meet criteria for a specific disease can be labeled 'positive ANA' and monitored longitudinally.
  • Follow these patients with regular serologies, urine, and labs — and co-manage with rheumatology — to catch anything that develops over time.