Microbiological Features and Risk Factors in Patients With Diabetic Foot Ulcers

Approximately 25% of people with diabetes will experience diabetic foot ulcers (DFUs) during their lifetime. The present study was designed to evaluate the prevalence of diabetic foot infection among patients with DFUs and to identify the microorganisms isolated from the DFUs. This study also aimed to determine predisposing factors contributing to these infections at the authors' wound care clinic at the Rajaii and Velayat University Hospitals in Qazvin, Iran.

This cross-sectional descriptive study included 500 patients with diabetes mellitus between May 2011 and April 2013 at the authors' wound care clinic in Qazvin, Iran. All demographic, clinical, and laboratory data such as age, sex, duration of diabetes (years), duration of DFUs before inclusion in the study, size of ulcer (cm2), glycosylated hemoglobin (HbA1c), and results of ulcer culture were collected for each case. The collected data were analyzed using SPSS software (SPSS Inc, Chicago, IL). A P value less than 0.05 was considered significant.

Overall, 54 (11%) patients with infected ulcers were found in the present study. Among patients with infected DFUs, the most commonly isolated microorganism was Pseudomonas aeruginosa, which infected 35% of patients, followed by Staphylococcus aureus in 19% of patients, and methicillin-resistant S. aureus in 6% of patients. Additionally, in the multivariable logistic regression model, age > 65 years, ulcer size > 2 cm2, and HbA1c > 7% were associated with the occurrence of an infection in DFUs.

Periodic examination of the feet of patients with diabetes is necessary. In addition, to decrease the prevalence of infected DFUs, more attention to the described risk factors is recommended.