I did a little looking around since my last post and it seems that Dalmations are uniquely affected by this. Here's a link with some info...
Uric Acid Stones in Dalmatians
Here's some more info from the DCA....
Dalmatian Club of America - 15 Years' Data of Almost 3000 Dalmatian Urinary Stones
Here's the link for the genetic test available....
Hyperuricosuria
Here's a short quote from the link.....
"The trait can occur in any breed but is most commonly found in the Dalmatian, Bulldog and Black Russian Terrier. Dalmatians are considered to be homozygous for hyperuricosuria."