Encephalopathy: Encephalopathy (abnormal brain function) has a variety of causes. Generally, they stem from lack of nutrients, infection, poisoning, structural changes, or anoxia. Within these categories encephalopathy can be cause from lack of oxygen during childbirth, stroke, head injury, liver disease, kidney disease, high blood pressure, bacterial, viral, or fungal infections, ischemia, and metabolic dysfunction. Treatment of encephalopathy depends on the cause.