Martin Desrosiers

Distinct immunopathologic characteristics of various types of chronic rhinosinusitis in adult Chinese

BACKGROUND Chronic rhinosinusitis (CRS) with nasal polyps (CRSwNP) and without nasal polyps (CRSsNP) is reported to be different in inflammatory patterns of the sinonasal mucosa in white patients. Studies in nonwhite populations may further be helpful to understand the pathogenic mechanisms of CRS. OBJECTIVE To investigate the immunopathologic profiles of CRSwNP and CRSsNP in adult Chinese. METHODS Histologic characteristics of surgical samples were analyzed in 50 controls, 94 CRSsNP patients, and 151 CRSwNP patients. Tissue samples from 17 controls, 36 CRSsNP patients, and 45 CRSwNP patients were stained for CD3, CD4, CD8, CD20, CD68, myeloperoxidase, and dendritic cell lysosome-associated membrane protein. Expression profiles of transcription factors of T-cell subsets in relation to cytokines and a marker of natural killer T cell (Valpha24) were examined by means of quantitative RT-PCR. RESULTS Over half of CRSwNP patients presented noneosinophilic inflammation. CRSwNP had a higher number of eosinophils, plasma cells, and CD3(+), CD8(+), CD20(+), and CD68(+) cells and a lower myeloperoxidase expression rate than CRSsNP. Expression levels of transcription factors and cytokines of T(H)1/T(H)2/T(H)17 were increased, whereas the expression rate of Forkhead box p3 and TGF-beta1 was decreased in both CRSsNP and CRSwNP compared with controls. Comparing CRSsNP and CRSwNP, CRSsNP had higher levels of IFN-gamma expression, whereas only eosinophilic CRSwNP demonstrated an enhanced expression of GATA-3 and IL-5. Compared with noneosinophilic CRSwNP, an exaggerated T(H)2/T(H)17 reaction and Valpha24 expression were found in eosinophilic CRSwNP. CONCLUSION Both Chinese CRSsNP and CRSwNP patients demonstrate impaired regulatory T cell function and enhanced T(H)1/T(H)2/T(H)17 responses. CRSsNP is confirmed to be a predominant T(H)1 milieu, whereas T(H)2 skewed inflammation with predominant T(H)17 reactions, and infiltration of natural killer T cells can be demonstrated only in eosinophilic CRSwNP, but not in noneosinophilic CRSwNP.

Biofilm Formation by Staphylococcus Aureus and Pseudomonas Aeruginosa is Associated with an Unfavorable Evolution after Surgery for Chronic Sinusitis and Nasal Polyposis

OBJECTIVES: To determine whether biofilm-forming capacity of bacteria demonstrated in chronic rhinosinusitis (CRS) has an impact on persistence of the disease following endoscopic sinus surgery (ESS). METHOD: Thirty-one bacterial strains recovered from 19 patients with CRS at least 1 year post-ESS. Evolution of disease was assessed by questionnaire and endoscopy as favorable or unfavorable. The bacteria were cultured on a 96-well culture plaque and a semi-quantitative method using crystal violet to quantify biofilm production was used. RESULTS: Twenty-two of 31 samples produced a biofilm thicker or equal to the positive control. Biofilm production was noted in 6/10 Pseudomonas aeruginosa isolates, 8/10 Staphylococcus aureus, and 8/11 coagulase-negative staphylococci. Biofilm formation was associated with a poor evolution for Pseudomonas aeruginosa and Staphylococcus aureus, but not coagulase-negative staphylococcus. CONCLUSION: There is a correlation between in vitro biofilm-producing capacity by Pseudomonas aeruginosa and Staphylococcus aureus and unfavorable evolution after ESS, suggesting a role for biofilm production in chronic sinusitis.

Canadian clinical practice guidelines for acute and chronic rhinosinusitis

This document provides healthcare practitioners with information regarding the management of acute rhinosinusitis (ARS) and chronic rhinosinusitis (CRS) to enable them to better meet the needs of this patient population. These guidelines describe controversies in the management of acute bacterial rhinosinusitis (ABRS) and include recommendations that take into account changes in the bacteriologic landscape. Recent guidelines in ABRS have been released by American and European groups as recently as 2007, but these are either limited in their coverage of the subject of CRS, do not follow an evidence-based strategy, or omit relevant stakeholders in guidelines development, and do not address the particulars of the Canadian healthcare environment.Advances in understanding the pathophysiology of CRS, along with the development of appropriate therapeutic strategies, have improved outcomes for patients with CRS. CRS now affects large numbers of patients globally and primary care practitioners are confronted by this disease on a daily basis. Although initially considered a chronic bacterial infection, CRS is now recognized as having multiple distinct components (eg, infection, inflammation), which have led to changes in therapeutic approaches (eg, increased use of corticosteroids). The role of bacteria in the persistence of chronic infections, and the roles of surgical and medical management are evolving. Although evidence is limited, guidance for managing patients with CRS would help practitioners less experienced in this area offer rational care. It is no longer reasonable to manage CRS as a prolonged version of ARS, but rather, specific therapeutic strategies adapted to pathogenesis must be developed and diffused.Guidelines must take into account all available evidence and incorporate these in an unbiased fashion into management recommendations based on the quality of evidence, therapeutic benefit, and risks incurred. This document is focused on readability rather than completeness, yet covers relevant information, offers summaries of areas where considerable evidence exists, and provides recommendations with an assessment of strength of the evidence base and degree of endorsement by the multidisciplinary expert group preparing the document.These guidelines have been copublished in both Allergy, Asthma & Clinical Immunology and the Journal of Otolaryngology-Head and Neck Surgery.

Effectiveness of topical antibiotics on Staphylococcus aureus biofilm in vitro

Background In vitro biofilm-producing capacity in isolates of Staphylococcus aureus and Pseudomonas aeruginosa collected from the sinus cavities after endoscopic sinus surgery (ESS) are associated with a poor outcome in patients with chronic rhinosinusitis (CRS). However, conventional oral antibiotic therapy is frequently ineffective in eradicating bacteria in the biofilm form. Increasing the concentration of antibiotics may offer a means of countering this resistance. The aim of this study was to determine the in vitro activity of moxifloxacin (MOXI) against S. aureus in biofilm form (recovered from patients with CRS at least 1 year post-ESS). Method This study was performed in a research microbiology laboratory, where five isolates of S. aureus with known biofilm-forming capacity were cultured in Tryptic Soy Broth 0.5% glucose in 96-well plates at 37°C for 24 hours. After visual confirmation of biofilm formation, plates were incubated in phosphate-buffered saline (PBS) or with MOXI at concentrations of 0.1×, 1×, 100×, and 1000× minimal inhibitory concentration (MIC) for an additional 24 hours. Biofilm from 3 wells of each concentration were collected and sonicated and the number of viable bacteria was determined by serial dilution and plating. Results After incubation, the number of viable bacteria was similar for nontreated and MOXI-treated biofilms at MIC and sub-MIC levels. However, MOXI at 1000X (0.1–0.2 mg/mL) gave a 2 to 2.5 log reduction in number of viable bacteria. Conclusion In vitro results show that increased concentrations of antibiotics, easily attainable in topical solutions, are effective in killing bacteria in bacterial biofilms. This suggests a role for topical antibiotic therapies in the treatment of biofilm infections.

Identification of susceptibility genes for complex diseases using pooling-based genome-wide association scans

The success of genome-wide association studies (GWAS) to identify risk loci of complex diseases is now well-established. One persistent major hurdle is the cost of those studies, which make them beyond the reach of most research groups. Performing GWAS on pools of DNA samples may be an effective strategy to reduce the costs of these studies. In this study, we performed pooling-based GWAS with more than 550,000 SNPs in two case-control cohorts consisting of patients with Type II diabetes (T2DM) and with chronic rhinosinusitis (CRS). In the T2DM study, the results of the pooling experiment were compared to individual genotypes obtained from a previously published GWAS. TCF7L2 and HHEX SNPs associated with T2DM by the traditional GWAS were among the top ranked SNPs in the pooling experiment. This dataset was also used to refine the best strategy to correctly identify SNPs that will remain significant based on individual genotyping. In the CRS study, the top hits from the pooling-based GWAS located within ten kilobases of known genes were validated by individual genotyping of 1,536 SNPs. Forty-one percent (598 out of the 1,457 SNPs that passed quality control) were associated with CRS at a nominal P value of 0.05, confirming the potential of pooling-based GWAS to identify SNPs that differ in allele frequencies between two groups of subjects. Overall, our results demonstrate that a pooling experiment on high-density genotyping arrays can accurately determine the minor allelic frequency as compared to individual genotyping and produce a list of top ranked SNPs that captures genuine allelic differences between a group of cases and controls. The low cost associated with a pooling-based GWAS clearly justifies its use in screening for genetic determinants of complex diseases.

Methods for removing bacterial biofilms: in vitro study using clinical chronic rhinosinusitis specimens.

Background Bacterial biofilms may be involved in refractory chronic rhinosinusitis (CRS). In vitro, we studied methods for removing biofilms formed by Staphylococcus aureus and Pseudomonas aeruginosa. Methods Bacterial isolates were obtained from patients with refractory CRS and were plated and treated with either static administration of citric acid/zwitterionic surfactant (CAZS), saline delivered with hydrodynamic force, or CAZS delivered hydrodynamically. Results were assessed by counting colony-forming units (CFUs) and by confocal scanning laser microscopy (CSLM). Results All treatments produced significant reductions in CFU counts (p ≥ 0.002). Hydrodynamic CAZS provided the greatest reduction, decreasing CFU counts from control values by 3.9 ± 0.3 logs and 5.2 ± 0.5 logs for S. aureus and P. aeruginosa, respectively (99.9% reduction; p = 0.001). CSLM showed decreases in biofilm coverage. Conclusion Hydrodynamic delivery of a soap-like surfactant and a calcium-ion sequestering agent may disrupt biofilms associated with CRS. Our results may be relevant to a new approach to refractory CRS.

Expression of prostaglandin D synthase and the prostaglandin D2 receptors DP and CRTH2 in human nasal mucosa

Abstract Background : Prostaglandin D 2 (PGD 2 ) is released from mast cells during the allergic response. Objective : Since PGD 2 has been shown to induce nasal congestion in humans, we investigated the distribution of hematopoietic prostaglandin D synthase (PGDS) and the two PGD 2 receptors, DP and CRTH2 in human nasal mucosa from healthy subjects and subjects suffering from polyposis, a severe form of chronic rhinosinusitis. Methods : DP mRNA expression was detected by in situ hybridization while PGDS, CRTH2 and various leukocyte markers expression were revealed by immunohistochemistry. Results : In the normal mucosa, PGDS was only detected in few resident mast cells while CRTH2 was undetectable. In contrast, DP receptor mRNA was detected in epithelial goblet cells, serous glands and in the vasculature. In the nasal mucosa of subjects suffering from polyposis: (1) PGDS was detected in mast cells and other large infiltrating inflammatory cells, (2) both DP mRNA and CRTH2 were detected in eosinophils and (3) CRTH2 was detected on a subset of infiltrating T cells. Although DP mRNA could not be detected in the T cells invading the nasal mucosa, it was found to be expressed in the T cells present in the lymph node and the thymus from normal individuals. Conclusion : This study indicates that cells capable of producing PGD 2 are present in the nasal mucosa and that both PGD 2 receptors, DP and CRTH2, might play a role in inflammatory disease of the upper airways.

International Consensus Statement on Allergy and Rhinology: Rhinosinusitis

Isam Alobid, MD, PhD1, Nithin D. Adappa, MD2, Henry P. Barham, MD3, Thiago Bezerra, MD4, Nadieska Caballero, MD5, Eugene G. Chang, MD6, Gaurav Chawdhary, MD7, Philip Chen, MD8, John P. Dahl, MD, PhD9, Anthony Del Signore, MD10, Carrie Flanagan, MD11, Daniel N. Frank, PhD12, Kai Fruth, MD, PhD13, Anne Getz, MD14, Samuel Greig, MD15, Elisa A. Illing, MD16, David W. Jang, MD17, Yong Gi Jung, MD18, Sammy Khalili, MD, MSc19, Cristobal Langdon, MD20, Kent Lam, MD21, Stella Lee, MD22, Seth Lieberman, MD23, Patricia Loftus, MD24, Luis Macias‐Valle, MD25, R. Peter Manes, MD26, Jill Mazza, MD27, Leandra Mfuna, MD28, David Morrissey, MD29, Sue Jean Mun, MD30, Jonathan B. Overdevest, MD, PhD31, Jayant M. Pinto, MD32, Jain Ravi, MD33, Douglas Reh, MD34, Peta L. Sacks, MD35, Michael H. Saste, MD36, John Schneider, MD, MA37, Ahmad R. Sedaghat, MD, PhD38, Zachary M. Soler, MD39, Neville Teo, MD40, Kota Wada, MD41, Kevin Welch, MD42, Troy D. Woodard, MD43, Alan Workman44, Yi Chen Zhao, MD45, David Zopf, MD46

Impact of rhinosinusitis in health care delivery: the Quebec experience.

OBJECTIVE Rhinosinusitis is a common disease affecting 135 per 1,000 population. The cost and the impact on quality of life of this disease are considerable. Health care delivery for a particular disease is evaluated through the health impact of the disease, outcomes of treatments, and their costs. This article reviews our experience with rhinosinusitis and its impact on health, as measured using a generic quality of life instrument, the Medical Outcome Study 36-Item Short-Form Health Survey (SF-36), in a selected patient population. Outcomes of treatments will be introduced, and the economic impact of chronic rhinosinusitis based on a U.S. study will be discussed. MATERIAL AND METHODS One hundred and ten patients (divided into three subgroups: recurrent acute rhinosinusitis, chronic rhinosinusitis, and nasal polyposis) completed the SF-36 survey on the day of the diagnostic visit in the outpatient sinus clinics of two hospitals. RESULTS The scores of the SF-36, in chronic rhinosinusitis, are compared with the normative values of a healthy U.S. population showing statistically significant differences in seven of eight domains. A comparison of the scores of chronic rhinosinusitis with a U.S. study on chronic rhinosinusitis shows statistically significant differences in five of eight domains. A comparison of the scores in the three diagnostic subgroups shows a statistical significance in two domains: bodily pain and vitality are more affected in recurrent acute and chronic rhinosinusitis. CONCLUSIONS Chronic rhinosinusitis affects the quality of life of patients with rhinosinusitis and represents an important health burden. Some differences are noted with the U.S. chronic rhinosinusitis population. Recurrent acute and chronic rhinosinusitis seem to have more impact on vitality and bodily pain than nasal polyposis.

Genetic association study of FOXP3 polymorphisms in allergic rhinitis in a Chinese population.

The FOXP3 gene encodes a transcription factor thought to be essential for the development and function of regulatory T cells, which are prevailing mediators of immunological tolerance via suppression/modulation of both T helper (Th)-1 and Th-2 mediated immune responses. Previous studies have demonstrated an association between common polymorphisms in FOXP3 and a number of immune diseases. The aim of this study was to investigate whether genetic polymorphisms at the FOXP3 locus predispose to allergic rhinitis (AR) in a Chinese Han population. Six polymorphisms in promoter and intron areas were genotyped in 193 AR subjects and 191 healthy controls. Twelve exons were also analyzed among cohorts of 157 AR patients and 118 healthy controls. Whole-population and gender strata analyses revealed that no single nucleotide polymorphisms in FOXP3 were identified as significantly associated with AR. Regarding the stratified analysis for heterozygotes and homozygotes, the heterozygous allele in rs3761548 (p = 0.020, OR(Het) = 3.12) appeared significant. Subgroup analysis for the presence of different allergen allergies also demonstrated a significant association for house dust mites (rs3060515, p = 0.010, odds ratio (OR) = 2.18; rs3761547, p = 0.013, OR = 2.00). Additionally, no polymorphisms in coding regions contributing to a susceptibility to AR were noted. Our study provides the first evidence for the association of the FOXP3 polymorphism with AR in a Chinese population.