Are biofilms associated with an inflammatory response in chronic rhinosinusitis?

ArticleinInternational Forum of Allergy and Rhinology 1(5):335-9 · September 2011with8 Reads
DOI: 10.1002/alr.20060 · Source: PubMed
Abstract
Bacterial biofilms have been identified on the sinonasal mucosa of patients with chronic rhinosinusitis (CRS) but also on control samples. Their role in the disease pathogenesis is unproven. The objective of this study was to further evaluate the role of biofilms in CRS by assessing whether they are associated with an inflammatory response. Mucosal samples were collected from 18 patients with CRS and 7 normal subjects. Bacteria on the mucosal surface were identified by Gram stain. Immune cells were identified by Giemsa stain and immunohistochemistry (IHC). The number of local immune cells was recorded beneath areas of the mucosal surface both colonized with and free from bacteria. In CRS patients, biofilms that were directly opposed to a disrupted epithelial layer were associated with more T lymphocytes (p = 0.01), and more macrophages (p = 0.003) than areas of mucosa without bacteria present. Biofilms associated with but not directly opposed to the epithelium were not associated with raised numbers of immune cells. Not all surface bacterial colonies are associated with a particular inflammatory response in CRS. Biofilms adherent to a disrupted epithelial layer are associated with higher numbers of immune cells and therefore appear to have a role in the pathogenesis of CRS.
    • "It has been suggested that Staphylococcus aureus biofilm fosters a Th2 adaptive immune response independent of any Staphylococcus aureus superantigen effect [214]. Recent studies suggest that disruption of the host epithelium may permit biofilm mediated inflammatory effects on the sinonasal tissues [215]. It is widely accepted that biofilms are a bacterial adaptation facilitating resistance to host defenses and antibiotics, helping to foster recalcitrant diseases. "
    [Show abstract] [Hide abstract] ABSTRACT: Chronic rhinosinusitis (CRS) is a public health problem that has a significant socio-economic impact. Moreover, the complexity of this disease due to its heterogeneous nature based on the underlying pathophysiology - leading to different disease variants - further complicates our understanding and directions for the most appropriate targeted treatment strategies. Several International/national guidelines/position papers and/or consensus documents are available that present the current knowledge and treatment strategies for CRS. Yet there are many challenges to the management of CRS especially in the case of the more severe and refractory forms of disease. Therefore, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), a collaboration between EAACI, AAAAI, ACAAI, and WAO, has decided to propose an International Consensus (ICON) on Chronic Rhinosinusitis. The purpose of this ICON on CRS is to highlight the key common messages from the existing guidelines, the differences in recommendations as well as the gaps in our current knowledge of CRS, thus providing a concise reference. In this document we discuss the definition of the disease, its relevance, pharmacoeconomics, pathophysiology, phenotypes and endotypes, genetics and risk factors, natural history and co-morbidities as well as clinical manifestations and treatment options in both adults and children comprising pharmacotherapy, surgical interventions and more recent biological approaches. Finally, we have also highlighted the unmet needs that wait to be addressed through future research.
    Full-text · Article · Oct 2014
    • "The resultant mucociliary impairment is then likely to promote further bacterial adherence and prevent bacterial clearance by the host's immune system. Interestingly, when bacterial biofilms are observed in areas of epithelial damage, there is a consistent elevation in Tlymphocyte and macrophage numbers, indicating a local inflammatory response [56]. If the epithelial layer has not been disrupted by the biofilm, this leukoattractant effect is not observed, further highlighting the significance of epithelial damage in the pathogenesis of biofilm-associated CRS. "
    [Show abstract] [Hide abstract] ABSTRACT: Chronic rhinosinusitis (CRS) is a very common condition that remains poorly understood from a pathogenic standpoint. Recent interest has been sparked by a potential role for biofilms in this process, with a significant body of evidence implicating them in inciting sinonasal inflammation. Biofilms are clearly present on the sinus mucosa of CRS patients, and their presence there is associated with severe disease characteristics and surgical recalcitrance. We are beginning to understand the importance of the species within these biofilms, but there may be other as-yet-unidentified factors at play in influencing disease outcomes. Recent exciting research has emerged documenting the immune response to the presence of biofilms-research that will ultimately solidify the nature and extent of the contribution of biofilms in CRS pathogenesis. Future research should focus on evidence-based antibiofilm treatments with reference to efficacy and timing of treatment.
    Full-text · Article · Apr 2012
  • [Show abstract] [Hide abstract] ABSTRACT: Some patients with chronic rhinosinusitis (CRS) exhibit thickening of the sinus bones that has been termed osteitis. The histopathology and microbiology of these changes have not been fully described. The aim of this study was to look for the presence of bacteria and immune cells within samples of bone from patients with and without CRS and correlate these findings to radiological findings. Bone on the anterior face of the sphenoid was examined radiologically and histologically in 8 patients with CRS with nasal polyposis, 8 patients with CRS without polyposis, and 6 control patients with pituitary adenomas and normal sinuses. Bone thickness and density were measured by computed tomography (CT) scanning. Bone samples were collected intraoperatively and 20 tissue sections were analyzed for each patient. Bacteria were identified by Giemsa and Gram stains. Immune cells were identified by conventional histology and immunohistochemistry. Small colonies of bacteria were identified within the bone in 3 of 16 CRS patients and 2 of 6 control subjects (p = 0.6). Isolated immune cells were identified within the bone in 3 of 16 CRS patients and 2 of 6 control subjects (p = 0.6) but both bacteria and immune cells occurred together in only 1 case. The presence of bacteria or immune cells within bone samples did not correlate with either bone thickness or bone density. This study describes the presence of bacteria and immune cells within a minority of CRS patients and normal controls. The bacterial microcolonies identified do not appear to be the cause of the bone changes seen in many CRS patients.
    Article · Mar 2012
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