Zosyn called a great first-line agent for postoperative pelvic cellulitis. (Advice from an Expert).

ST. Louis -- Piperacillin/tazobactam (Zosyn) is a superb first-line agent for postoperative pelvic cellulitis, Dr. Sebastian Faro said at the 12th International Pelvic Reconstructive and Vaginal Surgery Conference.

Stay away from the cephalosporins for this purpose, he urged, explaining that most women undergoing hysterectomy or other pelvic surgery receive antibiotic prophylaxis with a cephalosporin. These drugs select for resistant bacteria, including Enterococcus faecalis and the very dangerous Enterobacter cloacae, said Dr. Faro, professor of ob.gyn. and an infectious disease specialist at the University of Texas, Houston.

An intravenous broad-spectrum penicillin and beta-lactamase inhibitor combination is an excellent first choice for pelvic cellulitis. The [beta]-lactamase inhibitor broadens the Penicillin's spectrum of activity against gram-negative organisms. Why intravenous therapy? Because postoperative pelvic cellulitis is a potentially serious infection that can result in pelvic abscess.

He rates piperacillin / tazobactam as his top choice ahead of ampicillin/sulbactam and ticarcillin! clavulanic acid because of piperacillin's superior activity against gram-negative bacteria.

Dr. Faro, who said he has no financial interest in Zosyn, noted that he doses the drug at 3.375 g IV every 6 hours.

If the patient isn't improving within 36-48 hours on Zosyn, however, it's time to add gentamicin. She is probably infected by a gram-negative organism or enterococcus.

"But if I give Zosyn, and 12 hours later she's deteriorating, I don't wait for 48 hours. I add the gentamicin right then," Dr. Faro said at the conference, sponsored by the Society of Pelvic Reconstructive Surgeons.