I was hospitalized recently with peritonitis , not septic, but they said my cat scan showed something in my fatty tissue, they said it was my omentum, it was inflamed, maybe infected, possibly a portion of it could be dead. I'm very confused. What is an omentum and what is its function? They gave me intravaneous antibiotics and some prescription antibiotics to take at home. They said they don't know what causes this to happen. What am I looking at as far as future prognosis? Will this go away on its own? It's very painful and difficult to stand up straight which is what my job requires for eight hours.