Can vasculitis be diagnosed if symptoms have subsided? is there any need to see doc now or should i wait for next flareup? can waiting cause damage?

See below: I do not know the symptoms that you had, but it maybe wise to go ahead and see a rheumatologist to better what exactly is going.

Do not wait: Vasculitis remains a rare disease and the chances of you having vasculitis is small especially if symptoms are present intermittently. See a rheumatologist. Do not wait. Tests can be positive even when you are being reasonably well.