Evidence of potential threat of microbial drug resistance to commonly used antimicrobials in cases of active tubotympanic CSOM from Raipur, Chhattisgarh, India

Background: To identify the causative aerobic microbial pathogens of active tubotympanic (TT) type Chronic Suppurative Otitis Media (CSOM) and their antimicrobial susceptibility pattern. Method: A total of 248 clinically diagnosed CSOM patients were investigated for bacterial identification and antimicrobial sensitivity profiling. Results: Out of 248 cases, 226 cases (91.12%) were found positive and 22(8.87%) negative in culture. S.aureus (30.9%) emerged as the predominant cause of CSOM followed by P.aeruginosa (23.4%), Coagulase Negative Staphylococcus (CONS) (8.4%), Enterobacteriaceae bacilli (8.8%) and others. S.aureus exhibited significant drug resistance to Penicillin, Ciprofloxacin and Cotrimoxazole whereas P.aeruginosa showed 37.8% resistance to Ceftazidime.   The Enterobacteriaceae family of bacilli showed significant resistance to Cefotaxime, Amoxyclav and Cotrimoxazole. The meance of drug resistance posed a serious threat of emergence of drug resistance strains that could pose a challenge in subsequent management. TT-CSOM was predominantly caused by monomicrobial (179 cases, 79.2%) followed by polymicrobial(47 cases, 20.7%) aetiological agent. S.aureus was found most sensitive to Oxacillin and Clindamycin for Methicillin sensitive S.aureus (MSSA) and only Clindamycin for Methicillin Resistant S.aureus (MRSA) and CONS among primary antibiotics. In MSSA, MRSA and CONS, most sensitive secondary line of antibiotics included Linezolid and Gentamicin. P.aeruginosa showed highest sensitivity to Tobramycin, Piperacillin and Gentamicin among the primary and Piperacillin-Tazobactam, and Amikacin in the secondary line of antimicrobials respectively. The Enterobacteriaceae family of bacilli showed maximum susceptibility to Gentamicin and Amikacin among primary and secondary line of antimicrobials respectively. Conclusion: Compelling evidence of emergence of drug resistant microbial causative agent of TT-CSOM warrants the utmost need to strictly implement evidence ba