Erythrocyte sedimentation rate and C-reactive protein to monitor treatment outcomes in diabetic foot osteomyelitis.

This study sought to evaluate the effectiveness of the inflammatory markers, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP), in monitoring treatment of osteomyelitis in the diabetic foot. We screened 150 charts of patients admitted to our hospital with diabetic foot osteomyelitis (DFO), confirmed by positive results of bone culture and/or histopathology. We included patients who had an initial ESR/CRP within 72 hours of admission and two reported follow-up values. We dichotomised patients based on the outcomes wound healing, re-infection, recurrent ulceration, re-hospitalisation, additional surgery, re-amputation and death, all within 12 months, and analysed the trajectories of the markers over time. Our primary outcome, DFO remission, was defined as wound healing within 12 months of follow-up without re-infection. We included 122 subjects; 65 patients (53·3%) had a combination of positive culture and histopathology. Factors associated with DFO remission (n = 46) were a lower white blood count (WBC) at admission (P = 0·006) and a higher glomerular filtration rate (GFR, P = 0·049). Factors associated with healing were a lower WBC (P = 0·004), a higher GFR (P = 0·01), longer wound duration before admission (P = 0·01), location of the ulcer on the great toe (P = 0·01) and higher glycated haemoglobin (P = 0·03). Logistic regression analysis demonstrated no associations between DFO remission and other variables collected. Trajectories of the inflammatory markers showed an association between stagnating values of ESR and CRP and poor clinical outcomes. In this study population, the trajectories of both ESR and CRP during 12 months follow-up suggest a predictive role of both inflammatory markers when monitoring treatment of DFO.

The value of inflammatory markers to diagnose and monitor diabetic foot osteomyelitis.

In this study, we assessed the effectiveness of inflammatory markers to diagnose and monitor the treatment of osteomyelitis in the diabetic foot. We evaluated 35 consecutive patients admitted to our hospital with infected foot ulcers. Patients were divided in two groups based on the results of bone culture and histopathology: osteomyelitis and no osteomyelitis. The erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), procalcitonin (PCT), interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor alpha (TNFα), monocyte chemotactic protein-1 (MCP-1) and macrophage inflammatory protein-1 alpha (MIP1α) were measured at baseline after 3 and 6 weeks of standard therapy. PCT levels in the osteomyelitis group were significantly higher at baseline than in the group with no osteomyelitis (P = 0·049). There were no significant differences between the two groups in the levels of the other markers. CRP, ESR, PCT and IL-6 levels significantly declined in the group with osteomyelitis after starting therapy, while MCP-1 increased (P = 0·002). TNFα and MIP1α levels were below range in 80 out of 97 samples and therefore not reported. Our results suggest that PCT might be useful to distinguish osteomyelitis in infected foot ulcers. CRP, ESR, PCT and IL-6 are valuable when monitoring the effect of therapy.

Hybrid imaging with 99mTc-WBC SPECT/CT to monitor the effect of therapy in diabetic foot osteomyelitis.

This study sought to assess the utility of monitoring response to treatment of diabetic foot osteomyelitis (DFO) with Tc-99m WBC-labelled single photon emission computed tomography (SPECT/CT) imaging. This is a retrospective cohort study of 20 patients with DFO with sequential Tc-99m WBC-labelled SPECT/CT imaging. Radiologic findings of osteomyelitis were evaluated and imaging results were correlated with clinical outcomes subtracted from chart review. Successful treatment of osteomyelitis was defined by wound healing and/or lack of re-admission for bone infection of the same site within 1 year. The sensitivity, specificity, positive predictive value and negative predictive value of SPECT/CT to determine osteomyelitis treatment remission were 90%, 56%, 69% and 83%, respectively. Tc-99m WBC-labelled SPECT/CT imaging may be useful to help determine treatment outcomes for DFO.