OK - sort of answered my own question after doing a little research. Hope it helps others who might be wondering.
The Anti-Nuclear Antibody (ANA) Test
by Richard Silver, M.D., Professor of Medicine, Medical University of South Carolina (originally published in "Scleroderma Voice," 2002 Issue #1)
Question: When you have a positive ANA titer (concentration), can the pattern change, and if so, what does this mean? Is the pattern of the titer indicative of the disease you could develop?
Answer: Both the pattern and the titer (concentration) may change, and certain patterns are indicative of specific autoimmune diseases.
For example, the anti-centromere and the anti-nucleolar patterns are fairly specific for scleroderma, but other patterns such as the speckled pattern may be seen in both scleroderma and other connective-tissue diseases.
Generally, the ANA test is used by the rheumatologist to help support or refute a clinical impression; neither the pattern nor the titer is used to monitor the course of disease. Changes in pattern and titer are relatively insensitive, and therefore not very useful for the clinician.
diagnoses: mono 1972; postviral CFS 1997; fibro 1998; UCTD (dx limbo) 2007
meds: Plaquenil 400 mg, occasional low dose xanax for sleep aid, artificial tears w/ ointment at night, Advil/aspirin prn