Thanks for this question. At the core of my teaching slide is the notion that the ANA is a confirmatory test (based on having lupus like symptoms - beyond aches or pains); it is a horrible diagnostic test if used to screen for disease that might be lupus or autoimmune. An ANA of 1:320 is still a low positive that is meaningless if there arent SEVERAL lupus specific features in play. I dont and wouldnt repeat the test (to see where it goes) unless the patients symptoms and status evolves to more SLE features, and then... ordering an ANA is helpful and confirmatory. Ordering subserologies (Jo1 or SSA) if the ANA is negative is a mistake and unwise advise, as the diagnostic yield would be very very very low.
Bottom line - if the patient has pain (& you dont know why) and you find a +ANA (& your wondering if its lupus) -- it would be smart to refer to rheumatology to find out the cause of the pain (usually easier for rheum to explain the pain, than to try to fit the pain and low ANA into an unreasonable SLE diagnosis).
Thanks for this question. At the core of my teaching slide is the notion that the ANA is a confirmatory test (based on having lupus like symptoms - beyond aches or pains); it is a horrible diagnostic test if used to screen for disease that might be lupus or autoimmune. An ANA of 1:320 is still a low positive that is meaningless if there arent SEVERAL lupus specific features in play. I dont and wouldnt repeat the test (to see where it goes) unless the patients symptoms and status evolves to more SLE features, and then... ordering an ANA is helpful and confirmatory. Ordering subserologies (Jo1 or SSA) if the ANA is negative is a mistake and unwise advise, as the diagnostic yield would be very very very low.
Bottom line - if the patient has pain (& you dont know why) and you find a +ANA (& your wondering if its lupus) -- it would be smart to refer to rheumatology to find out the cause of the pain (usually easier for rheum to explain the pain, than to try to fit the pain and low ANA into an unreasonable SLE diagnosis).