INDUCE

Point of care tests to assist antibiotic prescribing decisions for diabetic foot ulcer infections.

Background

The lifetime risk of developing a diabetic foot ulcer (DFU) approaches 25% in the UK, resulting in direct costs for the care of DFUs at more than £250 million. Diagnosis of DFU infection remains entirely clinical with no objective test at the point of patient care to assist the clinician in antibiotic prescribing decisions.

C reactive protein (CRP), procalcitonin and calprotectin, are all markers of infection that are available as point of care tests (POCTs). However, the prognostic value of a combination of these results has not yet been evaluated for DFU infection.

Study aims

This pilot study, aimed to recruit 110 adult DFU patients with either no infection or mild ulcer infection, was based in community podiatry clinics and had three main aims:

1. to inform the feasibility of a subsequent RCT, particularly in terms of trial recruitment and use of the POCTs
2. to determine the cut-off points for optimal negative predictive value (NPV) and positive predictive value (PPV) of a combination of the POCTs using a robust gold standard for ulcer infection. This would give proof of principle that a composite POCT can be safely used to inform the decision about infection/no infection at initial assessment in a community setting
3. to develop an online educational tool for DFU infection and obtain feedback regarding its effectiveness from experienced clinicians and patients.