eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2024-12-30 17 4 2319 2327 10.13005/bpj/3027 62721 article Chitralekha Saikumar 1 Punithavathi Velmurugan 2 Aishwarya Jothi Ramalingam 3 Department of Microbiology, Sree Balaji Medical College & Hospital, Bharath Institute of Higher Education and Research, Chennai, Tamil Nadu, India. Millions of people worldwide suffer from chronic suppurative otitis media (CSOM), a recurrent infection of the ear that is particularly common in low-resource environments. Although there are several etiological factors, bacterial infection is a significant one. The two most frequently isolated bacteria are Staphylococcus aureus and Pseudomonas aeruginosa. Due to the emergence and spread of bacterial resistance to several antimicrobial agents and also their ability to form biofilms, treatment and recovery are made more challenging. Our aim was to identify the clinico-bacteriological profile, their antimicrobial susceptibility pattern and a molecular method to identify the antibiotic resistance genes of the most common isolates in this study. Following approval from the Institutional Human Ethics Committee (IHEC) and patient informed consent, we obtained ear discharge samples from 100 CSOM patients over a two-year period. The isolates were recognized by conventional microbiological methods. Polymerase chain reaction (PCR) was used for molecular characterisation in order to identify genes linked to antibiotic resistance (e.g., efflux pump-related genes associated with P. aeruginosa and mecA for S. aureus). Of the 100 patient samples, 84 samples showed positive results for culture; 58% of the Gram-positive cocci were S. aureus and 42% of Gram-negative bacilli were P. aeruginosa. Methicillin resistance in S. aureus  is indicated by the presence of the mecA gene (43%) and carbapenem resistance in P. aeruginosa is indicated by the presence of the bla_VIM gene (22%), according to genotypic study. Our work provides insight with regard to the genetic makeup of P. aeruginosa and S. aureus in CSOM patients, which demonstrates that these bacteria have several resistance genes that enable them to withstand antimicrobial therapy. https://biomedpharmajournal.org/vol17no4/bacteriological-profile-drug-resistance-pattern-and-its-molecular-characterisation-among-patients-with-chronic-suppurative-otitis-media-at-a-tertiary-care-hospital-in-south-india/ Chronic suppurative otitis media (CSOM) Coagulase negative Staphylococcus (CoNS) multidrug resistant (MDR) Methicillin resistant Staphylococcus aureus (MRSA) Pseudomonas aeruginosa Staphylococcus aureus