Clinical Distribution and Antimicrobial Resistance Characteristics of Pseudomonas aeruginosa Infections in Otorhinolaryngology in Eastern China: A Single-Center Retrospective Study.

BACKGROUND

Pseudomonas aeruginosa is a clinically important opportunistic pathogen in otorhinolaryngology, where chronic inflammation, impaired drainage, postoperative wounds, and device-associated biofilms may complicate treatment. Specialty-specific data linking anatomical distribution, multidrug resistance (MDR), and clinical outcomes remain limited in regional hospitals in China.

OBJECTIVE

To describe the clinical distribution and antimicrobial susceptibility profile of P. aeruginosa infections in otorhinolaryngology and to identify factors associated with MDR.

METHODS

This single-center retrospective cohort study included 112 consecutive patients with clinically adjudicated otorhinolaryngological infection and culture-confirmed P. aeruginosa at The First People's Hospital of Yongkang, Eastern China, from January to December 2024. MDR was defined as non-susceptibility to at least one agent in three or more antimicrobial categories. Group comparisons and multivariable logistic regression were performed.

RESULTS

The most common sites were the external ear canal/external ear (31.2%), middle ear/mastoid (25.0%), and nasal cavity/paranasal sinuses (21.4%). MDR was identified in 37 patients (33.0%). The highest susceptibility percentages were observed for colistin/polymyxin B (95.5%), amikacin (84.8%), and piperacillin-tazobactam (79.5%), whereas the highest resistance percentages were observed for aztreonam (32.1%), levofloxacin (27.7%), and ceftazidime (24.1%). Recent carbapenem exposure (adjusted odds ratio [aOR] 5.09, 95% confidence interval [CI] 1.22-21.19), postoperative indwelling devices/drainage (aOR 4.81, 95% CI 1.81-12.83), and hospital-acquired infection (aOR 2.52, 95% CI 1.02-6.23) were independently associated with MDR. MDR infections were associated with longer hospitalization, higher C-reactive protein levels, more antimicrobial regimen modifications, and lower clinical success.

CONCLUSION

This study provides specialty- and region-specific evidence that MDR P. aeruginosa is a substantial concern in otorhinolaryngological infections. In patients with recent carbapenem exposure, postoperative drainage or devices, or hospital-acquired infection, early culture acquisition, source control, and susceptibility-guided therapy are particularly important.