Usually the ANA is substantially +. The SSA and SSB are components of the ANA.
The ANA is the antinuclear antibody titer. It measure ALL antibodies....if that are +, then they try to find exactly which one is +, that is where the SSA and SSB come in for SjS.
So if your ANA is negative, usually the SSA and SSB are, or they tell you it's a lab error.
The ANA is the composite of all the extractable nuclear antigens, or ENA. The ENA consists of SSA, SSB, anti-sm, antidna, (Lupus) antirnps (MCTD), scl 70 (Sclero), anti Jo and a few more I can't remember.
Then to make it all more complex, any of these can appear in any disease.
Then the usual dance of rheumatology is to repeat it, and it undiagnose things, the rediagnose, then undiagnose....it's a circus unless things come back so definitive it hits them over the head.
Yes, we all want answers and some get them, some are a bit more mired. I have all the criteria for SjS, except the SSA and SSB. (I have almost all the complications too) I am still on the fence as to what I have, other than an autoimmune disease.
This stuff is a journey, think the Oddessy and the Illiad....you will be bored way before the end. Relax, enjoy the pre-Holiday hype...find the biggest turkey! I have a few walking around in the field back here.....