What are bacterial biofilms, and is there a link between these communities and chronic infections (e.g., osteomyelitis, prosthetic infection, wound infection, sinus infection)? What treatment strategies are recommended? — Jennifer Hurlow, GNP-BC, Germantown, Tenn.

In nature, many bacteria exist in complex community-like structures known as biofilms. Biofilm formation is a process in which microorganisms irreversibly (not removed by gentle rinsing) attach to and grow on a surface and produce extracellular polymers (mostly polysaccharides) that facilitate attachment and matrix formation. In industrial settings, biofilms may clog water pipes and storage tanks.

Biofilm-associated bacteria and fungi have been isolated from indwelling medical devices, including central venous catheters, prosthetic heart valves, urinary catheters, artificial hip prostheses, artificial valve prostheses, and intrauterine devices, and have the potential to cause infections in patients. Biofilm formation can result in chronic inflammation, impaired wound healing, and spread of infectious emboli. Biofilms have also been associated with native valve endocarditis, otitis media, and dental plaque and are a problem for people with cystic fibrosis.

Biofilm infections can be a serious problem because of increased resistance to antimicrobial agents. Standard antimicrobial susceptibility testing cannot accurately predict the efficacy of an agent against biofilm-associated organisms. Current research is directed at identifying mechanisms of biofilm formation to identify new targets for chemotherapy and provide approaches to control the formation of biofilms. — JoAnn Deasy, PA-C, MPH (150-11)