Acute Phase Reactants Predict the Risk of Amputation in Diabetic Foot Infection

Abstract

Background: Prediction of amputation would aid clinicians in the management of diabetic foot infections. We aimed to assess the predictive value of baseline and post-treatment levels of acute phase reactants in the outcome of patients with diabetic foot infections. Methods: We collected data prospectively during minimum follow-up of 6 months in patients with infected diabetic foot ulcers hospitalized in Dokuz Eylul University Hospital between January 1, 2003, and January 1, 2008. After excluding patients who did not attend the hospital for follow-up visits regularly (n = 36), we analyzed data from 165 foot ulcer episodes. Results: Limb ischemia and osteomyelitis were much more frequent in patients who underwent amputation. Wagner grade, which assesses ulcer depth and the presence of osteomyelitis or gangrene, was higher in patients who needed amputation. Ulcer size was slightly larger in the amputation group. Baseline and post-treatment C-reactive protein levels, erythrocyte sedimentation rates, white blood cell counts, and platelet counts were significantly elevated in patients who underwent amputation. Albumin levels were significantly suppressed in the amputation group. Univariate analysis showed that a 1-SD increase in baseline and post-treatment C-reactive protein levels, erythrocyte sedimentation rates, and white blood cell counts and a 1-SD decrease in post-treatment albumin levels were significantly associated with increased risk of amputation. Post-treatment C-reactive protein level was strongly associated with amputation risk. Conclusions: Circulating levels of acute phase reactants were associated with amputation risk in diabetic foot infections. (J Am Podiatr Med Assoc 101(1): 1–6, 2011)