Infected diabetic foot including osteomyelitis: Microbiology

Abstract

A variety of bacteria can be found in samples from diabetic foot infections, some more virulent than others, including many environmental colonisers. Virulence factors such as biofilms play a crucial role in the ability of microorganisms to persist in chronic wounds and cause infections. Pathogens such as Staphylococcus aureus, beta-haemolytic streptococci, Pseudomonas aeruginosa and anaerobes are the commonest isolates though the reported incidence can vary with the laboratory methods used. A robust sample collection technique is essential in making an accurate microbiological diagnosis and to ensure optimal choice of antibiotics. Duration of antimicrobial therapy in chronic diabetic foot infections remains controversial due to lack of high quality evidence but good antimicrobial stewardship can prevent their overuse while supporting therapeutic success. The incidence of multidrug resistant organisms is rising worldwide and increasing the need to preserve antibiotics for the longer term.