What did the vet recommend? How old is your dog? How high/abnormal were his protein values? Slight anomalies in lab work are not unusual for senior canines.
However, regarding homemade: http://skeptvet.com/Blog/?s=homemade+diet
I would stop the homemade immediately.
Maybe prescription food/therapeutic diet for a month or two or three (whatever your vet suggests) then retest?
If the labs are normal I would then go with something bland, how about Pro Plan Focus for sensitive skin and stomach. Add a little water or plain chicken broth.
PS: Wait, the labs are from 6 months ago? If so, time to return to the vet.
