Otopathogenic Pseudomonas aeruginosa – an emerging pathogen in ear infections

Pseudomonas aeruginosa, an opportunistic pathogen capable of causing various acute and chronic infections, is found to be significantly associated with ear infections. The study was aimed to isolate and determine the antibiogram of Otopathogenic P. aeruginosa. A retrospective single-centre study was done on patients with complaints of ear discharge for a period of one year. The samples were processed for both bacterial and fungal culture and antibiotic susceptibility testing was performed. Among 226 pus samples from various ear infections, 167 (73.8%) were culture positive, 17 (7.5%) were culture negative and 42 (18.6%) had commensals grown in culture. Of 167 (73.8%) culture- positive samples, 155 (92.8%) were monomicrobial and 12 (7.2%) were polymicrobial. Of 226 samples from ear infections, 60.61% were cases of Chronic Suppurative Otitis Media (CSOM) and 25.22% had Acute Suppurative Otitis Media (ASOM). From 167 culture-positive samples, 179 organisms were isolated. Out of 179 isolates, the predominant organisms isolated were Gram-negative bacilli (112, 62.6%), followed by Gram-positive cocci (35, 19.6%) and fungus (32, 17.8%). Among 179 organisms, P. aeruginosa (79, 44.1%) was predominantly isolated, followed by Staphylococcus aureus (34, 19%). Antimicrobial sensitivity pattern of isolated P. aeruginosa marked 100% sensitivity to Meropenem and Piperacillin tazobactum, more than 90% were sensitive to gentamicin, ceftazidime, cefaperazone, cefepime and 14% were found resistant to ciprofloxacin. Understanding the most predominant isolates from aural infections and their sensitivity pattern is imperative for the beginning of empirical treatment prior to receiving susceptibility reports from the laboratory.