Midtveisevaluering - Dag Harald Skutlaberg

ABSTRAKT

Biofilm produced by beta-haemolytic streptococci isolated from necrotizing soft tissue infections; characteristics, contribution to antimicrobial tolerance and clinical implications

A biofilm is a community of microorganisms sticking to a surface and embedded in an extracellular matrix consisting mainly of proteins, polysaccharides and extracellular DNA. The biofilm lifestyle protects the microorganism from the killing effect of both the immune system and of antimicrobial drugs. In clinical settings, biofilm formation is usually associated with chronic, low grade and device related infections.

Recently it has been shown that group A streptococci (GAS) form biofilms in necrotizing soft tissue infections (NSTIs). These infections are acute, rapidly progressing and potentially fatal conditions and despite consistently in vitro susceptibility of GAS to penicillin, clinical treatment failures are observed.

In this project we want to examine biofilm formation and its contribution to antimicrobial tolerance in clinical strains of beta-haemolytic streptococci group A, C and G isolated from patients with NSTIs. Further we plan to compare the biofilm proteome in selected strains of GAS with different biofilm characteristics. Finally we will examine the clinical significance of biofilm formation in NSTIs caused by beta-haemolytic streptococci group A, C and G.