Diagnostic value of procalcitonin, erythrocyte sedimentation rate (ESR), quantitative C-reactive protein (CRP) and clinical findings associated with osteomyelitis in patients with diabetic foot

BACKGROUND: The diagnosis of osteomyelitis is a key step of diabetic foot management. Procalcitonin (PCT) is a novel infection marker. This study aimed to investigate the diagnostic value of procalcitonin and other conventional infection markers and clinical findings in diagnosis of osteomyelitis in diabetic foot patients. METHODS AND MATERIALS: This diagnostic value study was carried out on ninety patients with diabetic infected foot ulcers admitted in Kashan Beheshti Hospital, 2016. After obtaining consent, 10 cc blood sample was taken for measuring serum PCT, CBC, ESR, CRP and FBS. Clinical characteristics of the wounds were noted. Magnetic resonance imaging of the foot was performed in all patients to diagnose osteomyelitis. All statistical analyses were done with the use of SPSS-16. RESULTS: PCT levels were 0.13 ± 0.02 ng/mili patients with osteomyelitis (n= 45) and 0.04 ± 0.02 ng/ml in patients without osteomyelitis (n= 45). PCT, Erythrocyte sedimentation rate and C-reactive protein was found significantly higher in patients with osteomyelitis (p< 0.001). The ROC curve was calculated for PCT. The area under the ROC curve for infection identification was 1 (p< 0.001). The best cut-off value for PCT was 0.085 ng/ml. Sensitivity, specificity, and positive and negative predictive values were 100%, 97.8%,97.8% and 100%, respectively. CONCLUSION: In this group of patients, PCT was useful to discriminate patients with bone infection. Also, Erythrocyte sedimentation rate and C-reactive protein can be used as a marker of osteomyelitis in diabetic patients.