Fanconi Syndrome is renal tubular dysfunction, the kidneys of an affected dog become ineffective at reabsorbing the nutrients that body needs and the dog then spills those nutrients in its urine. The easiest of the nutrients lost to test for is sugar hence the testing of urine for glucose but the reality is that Faconi dogs spill many nutrients including protein, glucose, vitamins, and minerals.
Symptoms include increased thirst, increased urination, spilling of sugar in the urine, and abnormal blood gas results. Fanconi is caused by a defective gene and is recessive in its inheritance pattern. There is now a gene marker test available for Fanconi Syndrome so there is no reason that a Fanconi Affected puppy ever be born. It can be prevented by testing the parents prior to breeding and making sure that at least one of the parents has tested clear for the disorder.