The role of soluble urokinase plasminogen activator receptor (suPAR) in the diagnostics of diabetic foot infection

Background: To investigate the role of soluble urokinase plasminogen activator receptor (suPAR) in the diagnosis of diabetic foot infection and to determine whether it is superior to other infection markers like leukocyte, neutrophil, erythrocyte sedimentation rate, c-reactive protein and procalcitonin. Methods: The present prospective study consisted of four groups: Group 1, healthy volunteers (n = 38); Group 2, patients without diabetic foot ulcers (n = 40); Group 3, diabetic patients with uninfected foot ulcers (n = 33); and Group 4, patients who had diabetic foot infection (n = 48). In each group, the leukocyte, neutrophil, erythrocyte sedimentation rate, c-reactive protein and procalcitonin and suPAR levels were examined. The results were then statistically compared. In addition, the patients in Group 4 were further divided according to the presence of mild, moderate, and severe infection. Also osteomyelitis were evaluated in Group 4 and statistically compared. Results: All infection markers were significantly higher in group 4 patients than those in the other three groups (p < .05). Similarly, all infection markers in the severe diabetic foot infection group were statistically higher than mild diabetic foot infection group (p < .05); however, only suPAR and erythrocyte sedimentation rate were significantly high in cases with osteomyelitis (p < .05). In the receiver operating characteristic analysis, the optimal cut-off value for suPAR was determined to be 2.8 ng/ml, and the sensitivity and specificity above this value were 95.8% and 82.8%, respectively. Conclusions: The current study demonstrated that suPAR might be used as a supportive diagnostic method for the diagnosis of diabetic foot infections.