infection that is getting worse she is 87

my grandma has an infection that could be steming from anywhere and nothing is working. She is getting worse, she is on a very high antibiotic and she is getting worse. She will not eat, she has no energy and she is very confused. I feel as though we are up aginst a brick wall, the nurses and drs just keep saying she is 87 sometimes this happens. Any advise or suggestions would be helpful. She is a diabetic with wound infections, as well as we just found out she tests positive for c-dif, her white blood cell count was 27 two weeks ago, yesterday it was 27.5 and she has been on this antibiotic for almost 2 weeks