Sometimes it takes quite awhile for the results to show up on the OFA site.
Fanconi is no longer the quick death sentence it was before Dr. Gonto's protocol, but many many vets are not knowledgeable about it. Dr. Gonto is more than willing to talk with your vet.
Because you have not seen symptoms yet, you may not need to get the blood gases yet. However, I personally would strip test for sugar in the urine more frequently, keeping in mind that some dogs spill intermittently especially in the early stages of the syndrome. The strips are relatively inexpensive and easy to read on your own - you don't need the vet to do this. You can get them at Costco or Sam's Club or any pharmacy. Just make sure you get the Diastix and not the Ketostix.
If you want, you can also join the Yahoo Fanconi Dogs list - just go to Yahoo Groups and look it up for contact info. There are people there with a wealth of experience with Fanconi affected dogs, and it's a wonderful, supportive group!
Don't panic, many dogs live long, happy, fulfilling lives with this syndrome, just love him for as long as you have him.
Terry and the Illusion Pack (6 previous dogs with Fanconi Syndrome, but I will never knowingly breed another!)