'Acute renal failure' is a term that is used to describe a decrease in renal function that occurs over days or weeks. In this case, the patient's renal failure was caused by acute tubular necrosis (ATN) - this is where part of the nephron structure in the kidney is destroyed, thus preventing the kidney from filtering blood properly and leading to a build-up of toxins in the body which can eventually lead to death. Histologically, this patient's kidneys showed evidence of this.
ATN can be caused by many different things; as the kidney is very susceptible to ischaemic damage. The intramuscular haemorrahage following injury sustained during a grand mal seizure appears to have led to hypovolaemia and hypotension in this case.