Antibiotic tx before prolapse, incontinence surgery cuts UTIs: macrobid vs. placebo

OB/GYN News, Nov 1, 2003 by Damian McNamara

HOLLYWOOD, FLA. -- Prophylaxis with the antibiotic Macrobid was tied to significantly fewer Symptomatic urinary tract infections than was placebo after surgery for pelvic organ prolapse and/or stress urinary incontinence.

This difference between groups was found at the time of suprapubic catheter removal, but was no longer significant at follow-up 6-8 weeks after surgery; said Dr. Dorothy N. Kamnmerer-Doak at the annual meeting of the American Urogynecologic Society.

In this double-blind trial, researchers assessed 414 women at six centers. All participants had a negative preoperative urine culture. A total of 202 women were randomized to receive Macrobid (nitrofurantoin) 100 mg / day, and 212 received placebo. The mean age was 54 years, the mean parity was 2.5, and most of the participants were white.

There were no significant differences between groups in terms of demographics, compliance, or perioperative complications, said Dr. Kammerer-Doak, an attending obstetrician and gynecologist at the Women's Health Service, Lovelace Healthcare Center, Albuquerque.

Suprapubic catheters were placed for postoperative drainage. Urine cultures were obtained at catheter removal and 6-8 weeks after surgery. Significantly fewer women in the Macrobid-treated group and symptomatic urinary tract infections (UTIs) at the time of suprapubic catheter removal, compared with the placebo group (7.4% vs. 18.8%, respectively). At the 6- to 8-week follow-up, the difference was only 2% vs. 5.5%.

Increased risk of UTI was not related to preoperative stage of prolapse, an elevated post-void residual (> 100 cc), or medical history. However, a higher risk was associated with higher estimated intraoperative blood loss, postoperative infectious complications, and increased length of the suprapubic catheter. The study was funded by grants from the National Institutes of Health and Procter & Gamble, which manufactures Macrobid.