Biofilms in ear, nose, and throat infections: how important are they?
BACKGROUND
Biofilms present a new challenging concept in sustaining chronic, common antibiotic-resistant ear, nose, and throat (ENT) infections. They are communities of sessile bacteria embedded in a matrix of extracellular polymeric substances of their own synthesis that adhere to a foreign body or a mucosal surface with impaired host defense. The aim of this paper is to review the literature on ENT diseases that can be attributed to biofilm formation and to discuss options for future treatment.


METHODS
Literature review from Medline and database sources. Electronic links and related books were also included.


METHODS
Controlled clinical trials, animal models, ex vivo models, laboratory studies, retrospective studies, and systematic reviews.


RESULTS
Biofilm formation is a dynamic five-step process guided by interbacterial communicating systems. Bacteria in biofilms express different genes and have markedly different phenotypes from their planktonic counterparts. Detachment of cells, production of endotoxin, increased resistance to the host immune system, and provision of a niche for the generation of resistant organisms are biofilm processes that could initiate the infection process. Effective prevention and management strategies include interruption of quorum sensing, inhibition of related genes, disruption of the protective extrapolymer matrix, macrolides (clarithromycin and erythromycin), and mechanical debridement of the biofilm-bearing tissues. With regard to medical indwelling devices, surface treatment of fluoroplastic grommets and redesign of cochlear implants could minimize initial microbial colonization.


CONCLUSIONS
As the role of biofilms in human infection becomes better defined, ENT surgeons should be prepared to deal with their unique and tenacious nature.
Vlastarakos
Petros V
PV
ENT Department, Hippokrateion General Hospital of Athens, Athens, Greece. pevlast@hotmail.com
Nikolopoulos
Thomas P
TP
Maragoudakis
Paul
P
Tzagaroulakis
Antonios
A
Ferekidis
Eleftherios
E
D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D001424:Bacterial Infections / Q000188:drug therapy / Q000382:microbiology / Q000517:prevention & control; D018441:Biofilms; D002908:Chronic Disease; D017291:Clarithromycin / Q000627:therapeutic use; D003054:Cochlear Implants / Q000382:microbiology; D003131:Combined Modality Therapy; D004917:Erythromycin / Q000627:therapeutic use; D005547:Foreign Bodies / Q000276:immunology; D006801:Humans; D008876:Middle Ear Ventilation; D010034:Otitis Media with Effusion / Q000188:drug therapy / Q000382:microbiology* / Q000517:prevention & control*; D010614:Pharynx / Q000382:microbiology* / Q000601:surgery*; D010641:Phenotype; D016459:Prosthesis-Related Infections / Q000382:microbiology* / Q000517:prevention & control*; D012852:Sinusitis / Q000188:drug therapy / Q000382:microbiology* / Q000517:prevention & control*
D000900:Anti-Bacterial Agents; D004917:Erythromycin; D017291:Clarithromycin