Yes, dialysis can cause hallucinations, and so also deteriorating kidney function. Usually hallucinations and violence are seen in psychotic disorders, especially schizophrenia. Kidney failure can also precipitate schizophrenia like symptoms. The other possibility is a brain infection. Please discuss this with your nephew’s doctor. Take care!
The medical advice given should not be considered a substitute for medical care provided by a doctor who can examine you. The advice may not be completely correct for you as the doctor cannot examine you and does not know your complete medical history. Hence this reply to your post should only be considered as a guiding line and you must consult your doctor at the earliest for your medical problem.