Comparative Clinical Outcomes of Patients with Diabetic Foot Infection Caused by Methicillin-Resistant Staphylococcus Aureus (MRSA) or Methicillin-Sensitive Staphylococcus Aureus (MSSA).

Few studies have addressed the interaction of specific pathogens with clinical outcomes in patients with diabetic foot infection (DFI). Our study aim was to compare the clinical outcomes among patients with DFI caused by methicillin-resistant Staphylococcus aureus (MRSA) with cases caused by methicillin-sensitive Staphylococcus aureus (MSSA). We gathered the data of 75 consecutive patients admitted at specialized outpatients diabetic with mild or moderate DFI in which S. aureus was isolated from bone or soft tissue specimens in pure or as a part of the polymicrobial culture. Patients were divided into two groups: those with MRSA infection and those with MSSA infection. Patients with MRSA diabetic foot infections were significantly associated with male gender (86% vs. 64%, P = .029), higher SINBAD Classification Score (3.6 ± 0.99 points vs. 2.8 ± 1.06 points, P = .001), longer mean wound evolution [17.8 (3;29.5) weeks versus 9.1 (1;12) weeks, P = .008], bone involvement [18 (50%) versus 9 (23.1%), P = .015] and longer mean healing time [18.2(8;28) weeks versus 9.1 (1;12) weeks, P = .008]. In addition, male gender (OR 8.81, 95% CI 2.00-38.84) and SINBAD Classification Score (OR 2.70, 1.46-5.00) were identified as independent risk factors for MRSA DFI. Significant differences in the number of surgical procedures to resolve infection [15 (41.7%) versus 13 (33.3%), P = .456] or in the mean healing time after surgical treatment [10.5 weeks (6.7;16.5) versus 6.1 weeks (3;8.7), P = .068] were not observed among groups, suggesting that when treatment is based on early and surgical debridement, MRSA infections are not associated with worse prognosis. In conclusion MRSA DFI has importance in clinical outcomes such as time to healing. We propose that recent lines of research regarding the genetic virulence of strains of S. aureus could provide new insights into our results.

Efficacy of preoperative and intraoperative skin and nail surgical preparation of the foot in reducing bacterial load.

BACKGROUND: A common problem associated with toenail removal surgery is the accompanying bacterial infection that often ensues. The foot has a particularly difficult anatomy to prepare antiseptically for surgery, which contributes to this wide-spread problem. OBJECTIVE: To compare the antiseptic efficacy of two skin pretreatment methods before toenail avulsion surgery. METHODS: Two presurgical methods were performed on 24 patients each (48 patients total). Swab samples were taken from each patient at five distinct stages (pretreatment, post-treatment, after surgery, after saline solution irrigation of the nail bed, and after phenol application) throughout the surgical procedure, and bacterial culture analysis was performed (total inocula count and identification of specific microorganisms). RESULTS: We found both methods to be effective at reducing the initial bacterial load when used at pretreatment, but the reduction in bacterial load was lost after the nail avulsion surgery, achieving values similar to the initial bacterial load before the presurgical scrub, from 5.17 and 5.04 log(10) colony-forming units (CFU)/cm(2) to 4.86 and 5.07 log(10) CFU/cm(2), respectively. An interoperative irrigation step was effective in reducing the bacterial load by 95.2% and 95.3%, respectively. STUDY LIMITATIONS: Our patients underwent phenol-based nail avulsion, resulting in no bacterial load after complete nail removal because of the intrinsic antiseptic nature of the phenol. CONCLUSIONS: Incorporation of intraoperative irrigation of sterile saline solution after nail avulsion surgery reduces potential bacterial load. Every effort should be made to lower the risk of contamination after nail plate avulsion.

Preoperative skin and nail preparation of the foot: comparison of the efficacy of 4 different methods in reducing bacterial load.

BACKGROUND: Orthopedic surgical procedures involving the foot and ankle are associated with high rates of infection. The optimal method of preparing the skin and nails for foot and ankle surgery remains unknown. OBJECTIVE: This study was conducted to compare the efficacy of 4 different methods of skin and nail preparation of the foot using various antiseptic solutions. METHODS: In this prospective, randomized study, 4 methods of skin and nail preparation were compared in terms of their efficacy in eliminating bacteria from the hallux nailfold and first web space of the normal foot in 28 healthy adult volunteers. Efficacy was determined by evaluating the difference in the total bacterial load before and after skin preparation. The foot-preparation solutions evaluated were 4% chlorhexidine gluconate, 70% isopropyl alcohol, and 7.5% to 10% povidone-iodine. RESULTS: The addition of alcohol to povidone-iodine was found to increase the efficacy of the preparation method. The nailfold remained contaminated after any of the preoperative skin- and nail-preparation methods studied. LIMITATIONS: This study did not measure clinically relevant infections, and the results may not correlate with decreased rates of infection after surgery. CONCLUSION: Incorporation of alcohol and povidone-iodine into the preoperative skin- and nail-preparation process may help reduce the bacterial load. Every effort should be made to lower the risk of contamination from the nail.