Risk factors for mortality among patients undergoing major amputations due to infected diabetic feet

Abstract Background Foot ulcers in patients with diabetes are a major public health problem and are often associated with lower limbs amputation and mortality in this population. Objectives To investigate the risk factors associated with mortality in patients with infected diabetic foot ulcers and major lower limb amputations. Methods This was an observational, retrospective, case-control study with a sample of 78 patients with infected diabetic foot ulcers who had major lower limb amputations at a Vascular Surgery Service at a university hospital. Results The mean age of the study sample was 63.8 ± 10.5 years, 54 (69.2%) were male, mean serum creatinine was 2.49 ± 2.4 mg/dL and mean serum hemoglobin was 7.36 ± 1.7 g/dL. There was a 47.4% rate of readmissions to the same hospital. Transtibial amputation was performed in 59.0%; and transfemoral amputation in 39.7% of the sample. In this sample, 87.2% had a positive culture, predominantly (68.0%) monomicrobial and nosocomial infection of ulcers was observed in 30.8%. The most common bacterial genera were Acinetobacter spp. (24.4%), Morganella spp. (24.4%) and Proteus spp. (23.1%). No bacterial genus was identified as a predictor of death. Creatinine level ≥ 1.3 mg/dL (OR 17.8; IC 2.1-150) and transfemoral amputation (OR 4.5; IC: 1.3-15.7) were associated with death. Conclusions Serum creatinine levels ≥ 1.3 mg/dL and transfemoral amputation were risk factors for death.