Are there clinical, laboratory, or imaging features that can help distinguish primary Sjögren’s syndrome from secondary Sjögren’s in patients with overlapping inflammatory arthritis or positive rheumatoid factor?

Such a good query. I don't really know, as associated SjD has been understudied. In my experience, associated Sjogren's does not look that different from Sjogren's alone. We have seen high ocular staining scores and markedly reduced unstimulated salivary flow in associated SjD (SLE, RA). In SjD, the...