How would you interpret a positive single specific markers like SSA or SSB in setting of working up an connective tissue disease, especially when ANA is negative?   

Ha! Good question. And this is an issue I literally just talked about with our residents during an autoimmune labs lecture that I give. If you have a negative ANA by IFA (immunofluorescence assay), the sensitivity of such a test is extremely high (99%) as hundreds of antinuclear antibodies are scre...