Canavan disease. Regarding canavan disease: it is a genetic disease which is quite rare but seen mostly in ashkenazi jews. There is an over productin of n-acetylaspartic acid in the brain. A metabolic specialist ought to be consulted. However a full organic acid test should be run to help delineate possible adjunct treatments. I am betting most pediatricians would not feel comfortable treating it.
Supportive care. At present, supportive care is what's recommended. This includes nutritional support (a gastrostomy tube is sometimes needed), physical therapy, and medication to treat abnormal muscle tone. Gene therapy is still in the experimental stage, but may someday be available.