Dry eyes, are they diagnostic of sjogren's syndrome?

Yes: Sjogren's syndrome is a combination of dry eyes, mouth and other mucous membranes. A biopsy of the salivary gland is usually diagnostic.

Sjogren's syndrome: Sjogren's syndrome = disease characterized by severe dry eyes + dry mouth + positive blood tests for ss-a/ ss-b.

No: Just because you eyes are dry does not mean you have sjogren's. Dry eyes is very common and can be due to a number of causes. As in the previous answer, sjogren's is dry eyes and dry mouth. There are blood tests for that condition, as we'll as a biopsy, although the latter is not a pleasant procedure to undergo. See your eye md for appropriate and treatment of your dry eyes.