What does dual pattern on a positive ana blood test mean ? other blood work is fine?

Depends on symptoms: ANA is a screen for lupus. The pattern was used in the past to assist in diagnosing lupus and related conditions, but we have better tests (i.e. Ena panel) that has made patterns less useful. But you cannot over interpret this test: ANA positivity, regardless of pattern, is not helpful without knowing your symptoms. Everything boils down to symptoms;; rheum md would be very helpful.

Antinuclear Antibody: An "ana" is a blood test used to screen a person for the possibility of several autoimmune diseases. It is important to remember that this is a screening test and a positive result only indicates more testing may be warranted. No blood test is perfect, and getting to a diagnosis is usually much more complex than drawing blood and looking at a number on the results report.