Hi John,
PRAL is an acronym for Potential Renal Acid Load. It is an estimate of how diet will affect your kidneys. Foods with lower PRAL create more alkaline, which is generally considered to be a good thing for health. For gout, there are strong indications that alkaline urine allows uric acid to be excreted quicker, and will lower uric acid for most gout sufferers. It’s complicated, but there are tests that can confirm if an alkalizing diet will help your gout.
Let me know if you want more details of how to plan an alkalizing diet for gout, and how to monitor it to assess your progress.