The microbiology and antimicrobial resistance patterns in chronic rhinosinusitis

The purpose of this study was to review the microbiology of chronic rhinosinusitis (CRS) in patients undergoing endoscopic sinus surgery (ESS) and comment on antimicrobial resistance trends. A retrospective review of 101 patients undergoing ESS during the period of 1997 to 2001 was performed. Patients were divided into groups based on their surgical history. Fifty-five patients without prior ESS history were placed in the primary group; 46 patients who had undergone prior ESS were placed in the revision group. Intraoperative microbiology culture data were reviewed and antimicrobial resistance data analyzed. Data on 101 patients were analyzed. There were 182 total cultures sent, yielding 257 isolates. The most common isolates were coagulase-negative Staphylococcus (SCN) (45% of cultures), gram-negative rods (25% of cultures), and Staphylococcus aureus (24% of cultures). Pseudomonas aeruginosa was isolated in 9% of cultures. When comparing the 2 patient groups, we did not find consistent trends in the differences in the prevalence of these isolates. Antimicrobial resistance for SCN ( P = .01) and S aureus ( P < .001) was greater in the revision surgery. Overall, 62% of patients were found to have at least 1 isolate with decreased antibiotic sensitivity. The most prevalent microorganisms in patients with CRS are SCN, S aureus, and gram-negative rods. Perhaps more importantly, the antimicrobial sensitivities of these microorganisms appear to be a growing problem. These findings suggest increased antimicrobial resistance in patients undergoing revision ESS when compared with patients undergoing surgery for the first time.