Microbiological Pattern, Antimicrobial Resistance and Prevalence of MDR/XDR Organisms in Patients With Diabetic Foot Infection in an Indian Tertiary Care Hospital

Foot infections are the most prevalent problem in persons with diabetes. The burden of multidrug resistant (MDR) microorganisms in diabetic foot infections (DFIs) is rising day by day. Given that, the present study aims to determine the variety of microorganisms isolated from the diabetic foot ulcers (DFUs), and their antibiotic sensitivity pattern. This prospective observational study was conducted for 1 year at Bharati Hospital and Research Centre, Pune, India. Clinically infected patients with DFU admitted to the surgery ward were included in this study. The specimen for microbiological studies is obtained from the wound swabs, soft tissue, and bone tissue as a part of routine clinical care. All demographic, clinical data, microbial culture results were collected, and evaluated for each case. Antimicrobial susceptibility testing to different agents was carried out using the VITEK-2(R) machine. A total of 110 microorganisms were isolated from 76 specimens, with an average of 1.4 organisms per lesion. Staphylococcus aureus (n = 27, 24.5%) and Escherichia coli (n = 17, 15.4%) were the most prevalent Gram-positive and Gram-negative organisms isolated, respectively. MDR organisms constituted up to 52 (47.2%), while 6 (5.4%) of the samples were extensively drug resistant (XDR). Methicillin-resistant S aureus (MRSA) accounted for up to 19 (70.3%) of the S aureus isolates, likewise extended-spectrum beta-lactamase producing microorganisms constituted 16 (14.5%) of total isolates in this study. Oxacillin and benzyl penicillin exhibited least susceptibility against Gram-positive bacteria, among Gram-negative organisms; cefuroxime, ceftriaxone, and ciprofloxacin were least sensitive. As most of the S aureus isolate in our study was MRSA, empirical antimicrobial therapy may include coverage for MRSA in a patient with risk factors associated with this pathogen. A crucial observation is the presence of XDR strains of Proteus mirabilis in DFIs, which is resistant to almost all the antimicrobials, tested. Appropriate antimicrobial selection may reduce the morbidity and the emergence of MDR organisms in DFIs.