gchiu: Very unusual for first presentation of gout to be knee swelling.
Needs confirmation with some fluid taken from your knee and examined under polarised light microscopy.
For most people, the reason they get gout is that their kidney function deteriorates with time, and they under excrete uric acid so that it accumulates in the body.
Id been getting knee pain for about 2 years prior, no swelling....suspect it was early signs of it "gout".
Kidney function in my tests was fine, I'm picking it was diet that needed attention and my body saying hey I cant get rid of all these purines you are loading me up on. I went though a period last year where I was consuming about 3-4 bottles of white wine per week.