Antibiotic Resistance Pattern of Pseudomonas aeruginosa-associated Pneumonia over a Period of 6 Years at a Teaching Hospital in Northern India

Abstract Background: Pseudomonas aeruginosa is a major cause of multidrug resistant (MDR) nosocomial pathogen isolated from clinical samples of patients admitted to the intensive care unit. Treating the ever-increasing antimicrobial resistance in P. aeruginosa isolates has turned into a challenge. Materials and Methods: All data were extracted from the hospital information system on P. aeruginosa pneumonia from July 2017 to July 2022. All isolates were identified by matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry and routine biochemicals. A comparison between the consequences of antibiotic susceptibility testing, demographics, and risk factors between the patients with community-acquired and nosocomial-acquired pneumonia due to either P. aeruginosa or multidrug-resistant P. aeruginosa was performed. Results: In this study, 576 (576/19224, 2.99%) patients developed P. aeruginosa pneumonia over 6 years. There were 114 (19.79%) cases of community-acquired pneumonia and 462 (80.21%) cases of nosocomially acquired pneumonia in this study. P. aeruginosa showed high resistance to cefoperazone-sulbactam and imipenem, which was statistically significant in cases of patients suffering from nosocomially acquired pneumonia compared to community-acquired pneumonia. High susceptibility to colistin was statistically significant in cases of community-acquired pneumonia compared to nosocomially acquired pneumonia. A total of 182 (182/576, 31.59%) deaths occurred among cases of P. aeruginosa pneumonia. Conclusion: This study explains the emergence of resistance among the P. aeruginosa isolates causing community-acquired pneumonia or nosocomially acquired pneumonia over 6 years.