The performance of serum inflammatory markers for the diagnosis and follow-up of patients with osteomyelitis.

Serum inflammatory markers, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), white blood cells (WBC), and procalcitonin (PCT), have been used for the diagnosis of foot infections in patients with diabetes. However, little is known about their changes during treatment of patients with foot infections. The aim of this prospective study was to examine the performance of serum inflammatory markers for the diagnosis and follow-up of patients with osteomyelitis. A total of 61 patients (age 63.1 ± 7.0 years, 45 men and 16 women, 7 with type 1 and 54 with type 2 diabetes) with untreated foot infection (34 with soft-tissue infection and 27 with osteomyelitis) were recruited. Diagnosis of osteomyelitis was based on clinical examination and was confirmed by imaging studies (X-ray, scintigraphy, magnetic resonance imaging). Determination of the inflammatory markers was performed at baseline, after 1 week, after 3 weeks, and after 3 months of treatment. At baseline, the values of CRP, ESR, WBC, and PCT were significantly higher in patients with osteomyelitis than in those with soft-tissue infections. The sensitivity and specificity for the diagnosis of osteomyelitis of CRP (cutoff value >14 mg/L) were 0.85 and 0.83, of ESR (cutoff value >67 mm/h) 0.84 and 0.75, of WBC (cutoff value >14 × 10(9)/L) 0.75 and 0.79, and of PCT (cutoff value >0.30 ng/mL) 0.81 and 0.71, respectively. All values declined after initiation of treatment with antibiotics; the WBC, CRP, and PCT values returned to near-normal levels at day 7, whereas the values of ESR remained high until month 3 only in patients with bone infection. From the inflammatory markers, ESR is recommended to be used for the follow-up of patients with osteomyelitis.