Personally, I have had undiagnosed sjogrens for about 15 years--dry eyes and mouth spells, neurological symptoms, etc, but I do not have any positive bloodwork at all. No ANA, SSa, SSB, CRP, ESR, etc. No typical autoimmune markers at all, but I have had this a long time. So, you could go a long time without showing anything. Recently, over the past three years, it has gotten worse but still no evidence other than symptoms.