My Husband Is Having Fevers And Chills And A Pain

My husband is having fevers and chills and a pain on the right side of his stomach area. 2 years ago he was in the hospital for an appendix rupturing. It had ruptured 3 weeks before seeing the doctor and was told by the doctor to go to ER. We did that and a CAT Scan showed a ruptured appendix and a soft ball size pus ball. The doctor drained it and said his appendix was gone no need to remove it. My question can his appendix flare up again? The pain is in the same area and he hasn't eaten. Hope you can help trying to get him to the dr but stubborn.