A study on the microbial profile of orthopedic implant infections and its risk factors in a tertiary care hospital

Aims: To identify the etiological agents of orthopedic implant infections in patients admitted in postoperative and septic ward. To identify the risk factors for orthopedic implant infection.  To study the Antimicrobial susceptibility pattern of the isolates with a view to formulate an empiric antibiotic regimen. To detect emerging pattern of resistance in these organisms by standard methods (CLSI). To know the prevalence of multidrug resistant pathogens among the isolates. Materials and Methods: The study period was one year. One hundred and sixty patients were investigated for early or late postoperative infections of orthopedic bone implants using conventional microbiological procedures. Antimicrobial susceptibility testing was then performed for the isolated bacteria according to the standard guideline. Results: Out of 160 Orthopedic implant infections, the most common procedure that is complicated by infection is Open interlocking nail (Tibia/Femur) (47.5%) followed by closed interlocking nail Tibia/Femur (13.75%). Tibia is the most commonly infected bone (53.75%) after implant surgery followed by Femur (26.87%). Diabetes mellitus and longer duration of surgery were the important risk factors noted in our study. A total of 169 isolates were recovered (166 aerobes and 3 anaerobes). Staphylococcus aureus is the most common organism isolated followed by Staphylococcus epidermidis and Proteus mirabilis. 51.21% of Staphylococcus aureus and 73.52% of Staphylococcus epidermidis were found to be methicillin resistant. The majority of isolated gram positive cocci were sensitive to Rifampin and Vancomycin. 75% of Klebsiella pneumonia and Proteus vulgaris, 70% of Proteus mirabilis and 58.82% of Escherichia coli were found to be ESBL producers. Conclusion: There is needed to develop a good treatment protocol for orthopedic implant infections and also to create a good protocol for prevention of orthopedic implant infections. Keywords: Orthopedic implant, Antimicr