Hi encephalopathy can be made worse by a high protein diet,consult your doctor about trying a low protien diet,you must check first because of malnutrician issues.
I'm sorry about your son I know it must be hard.
Encephalopathy is often worse after tips. The shunt bypasses the liver ( which use to clean the blood) which allows the possiblity of more toxins reaching the brain.
Other causes can be infections, dyhydration,GI bleed, Too much protein in diet,Constipation and some medications.
There have been cases where patients have had the tips reversed or occluded, But this can be dangerous.
Call his Dr. and let them know that the Encephalopathy is worse.