Azithromycin in high-risk, refractory chronic rhinosinusitus after endoscopic sinus surgery and corticosteroid irrigations: a double-blind, randomized, placebo-controlled trial.

BACKGROUND: Refractory chronic rhinosinusitis (CRS) remains a significant burden for patients, often leaving them with few therapeutic options that provide low-morbidity, long-term, and meaningful symptomatologic and endoscopic disease improvement. Macrolides have long been thought to offer both an immunomodulatory and antimicrobial effect. Our objective was to evaluate the efficacy of low-dose, long-term azithromycin in a carefully selected high-risk population failing appropriate medical therapy of budesonide nasal irrigations (BNIs) and endoscopic sinus surgery (ESS). METHODS: A double-blind, randomized, placebo-controlled trial was completed in a single tertiary-care center assessing the addition of 250 mg azithromycin, 3 times per week for 16 weeks, in adults failing ESS and high-volume BNIs. Associated comorbidities, as well as symptomatologic, microbiologic, and serologic values, were systematically collected. RESULTS: A total of 128 patients were enrolled and underwent ESS followed by BNI. At the 4-month post-ESS visit, 48 patients showed disease persistence and were randomized to azithromycin or placebo. Overall, azithromycin, when compared with placebo, did not show a statistically significant difference in disease clearance (54% vs 33%, respectively; p = 0.146), although patients with disease clearance who were on azithromycin showed significantly better 22-item Sino-Nasal Outcome Test score improvements than patients on placebo (18 vs -0.9, respectively; p = 0.046). In a subgroup analysis excluding aspirin-exacerbated respiratory disease (AERD) patients, azithromycin significantly improved disease clearance when compared with placebo (71% vs 35%, respectively; p = 0.031), with a number needed to treat of 3 (2.8). CONCLUSION: Low-dose azithromycin is a therapeutic option with few side effects. Its use can show favorable clinical outcomes in this difficult-to-treat population, especially if patients are AERD-negative.

CD34+ hemopoietic progenitor cells are potent effectors of allergic inflammation.

BACKGROUND: In steady state, hemopoietic progenitors constantly egress from the bone marrow (BM) into the blood and circulate through the peripheral tissues. In allergic diseases, the BM releases increased numbers of CD34(+) progenitor cells that migrate to the site of allergic inflammation, where they differentiate into tissue-dwelling and classic effector cells of allergy, such as mast cells, eosinophils, and basophils. OBJECTIVE: To examine whether peripheral blood CD34(+) cells in addition to being progenitors may also directly function as inflammatory effector cells. METHODS: Highly purified neonatal or adult blood CD34(+) cells were examined for the expression of thymic stromal lymphopoietin (TSLP) and IL-33 receptors and for their response to these cytokines as well as to supernatants of primary small airway epithelial cells and nasal explants from rhinosinusitis and control subjects. Sputum of patients with asthma was examined before and after allergen inhalation for the presence of IL-5 and IL-13-containing CD34(+) cells. RESULTS: Circulating CD34(+) cells expressed receptors for TSLP and IL-33 and responded to these cytokines by rapidly releasing high levels of proinflammatory T(H)2-like cytokines and chemokines. These cells were activated in a TSLP-dependent manner by the supernatant fluids from activated primary human small airway epithelial cells and from nasal explants of patients with chronic rhinosinusitis. Moreover, activated CD34(+) cells containing IL-5 and IL-13 could be detected in the sputum of individuals with allergic asthma, with numbers increasing in response to specific allergen inhalation challenge. CONCLUSION: Blood CD34(+) cells, in addition to being progenitors, may act as proinflammatory effector cells by themselves and directly contribute to the allergic inflammation.

Intranasal Application of Lactococcus lactis W136 Is Safe in Chronic Rhinosinusitis Patients With Previous Sinus Surgery.

Objective: Modulation of the dysbiotic gut microbiome with "healthy" bacteria via a stool transplant or supplementation is increasingly practiced, however this approach has not been explored in the nasal passages. We wished to verify whether Lactococcus lactis W136 (L. lactis W136) bacteria could be safely applied via irrigation to the nasal and sinus passages in individuals with chronic rhinosinusitis (CRS) with previous undergone endoscopic sinus surgery, and whether this was accompanied by bacterial community flora modification. Study Design: Prospective open-label pilot trial of safety and feasibility. Setting: Academic tertiary hospital center. Subjects and Methods: Twenty-four patients with CRS refractory to previous medical and surgical therapy received a 14-day course of BID sinus irrigations containing 1.2 × 109 CFU live L. lactis W136. Patients were monitored for safety using questionnaire, sinus endoscopy, otoscopy, UPSIT-40 smell testing, and endoscopically-obtained conventional sinus culture and a swab for 16S microbiome profiling. Results: All 24 patients receiving at least one treatment successfully completed treatment. L. lactis W136 probiotic treatment was safe, with no major adverse events or new infections. Treatment was associated with improvement in sinus symptoms, QOL, and mucosal scores, which remained improved during the subsequent 14-day observation period. Microbiome changes associated with treatment were limited to an increase of the pathobiont Dolosigranulum pigrum, a bacteria identified as potentially beneficial in the upper airways. Subgroup analysis suggested differences in microbiomes and responses for CRSsNP and CRSwNP phenotypes, but these did not attain significance. Conclusion: Intranasal irrigation of live L. lactis W136 bacteria to patients with refractory chronic rhinosinusitis was safe, and was associated with effects on symptoms, mucosal aspect and microbiome composition. Intranasal bacteria may thus find a role as a treatment strategy for CRS. Clinical Trials Registration: www.ClinicalTrials.gov. identifier: NCT04048174.

Polymorphisms in the interleukin-22 receptor alpha-1 gene are associated with severe chronic rhinosinusitis.

RATIONALE: Stimulation of interleukin-22 receptor alpha-1 (IL22RA1) was reported to increase the innate immune responses in inflammatory diseases. Moreover, a reduced level of IL22RA1 was found in patients with recalcitrant CRS with nasal polyps. OBJECTIVE: To explore association between single nucleotide polymorphisms (SNPs) in IL22RA1 and severe CRS. METHODS: We extracted DNA from 206 cases with severe CRS and 196 postal code-matched controls. Twenty-three SNPs in the IL22RA1 gene were selected from the pooling-based genome-wide association study and from the CEU HapMap dataset and genotyped. PLINK software was used to determine association. RESULTS: After Bonferroni correction, three SNPs (rs4292900 P(nom) = 0.0006, OR = 1.757; rs4648936 P(nom) = 0.0011, OR = 1.716; rs16829225 P(nom) = 0.0014, OR = 1.977) show significant differences in allelic frequencies between cases and controls. CONCLUSION: Polymorphisms in IL22RA1 are associated with severe CRS. Replication and functional studies are involved to better understand the mechanism by which these polymorphisms contribute to the pathogenesis of CRS.

Dietary modifications for refractory chronic rhinosinusitis? Manipulating diet for the modulation of inflammation.

BACKGROUND: An endotype of chronic rhinosinusitis (CRS) refractory to medical and surgical management is characterized by persistent T-helper 1/T-helper 17 inflammation of the sinus mucosa, which potentially facilitates colonization with dysbiotic microbial flora. Dietary interventions that target reduction of systemic inflammation are increasingly recommended as adjuncts to ongoing medical therapy in chronic disorders with a strong inflammatory component, such as cardiac disease, diabetes, and metabolic syndrome. Inflammation-reducing dietary modifications may thus be of benefit in patients with refractory CRS (RCRS). OBJECTIVE: To identify nonpharmacologic approaches that implicate modification of dietary factors, potentially reducing systemic level of inflammation in RCRS. METHODS: A systematic review of the literature was undertaken to identify dietary strategies for reducing inflammation in metabolic syndrome, diabetes, and cardiac disease. Mechanistic-based strategies for reducing systemic inflammation were identified and categorized to identify potential therapeutic avenues, which would be applicable to RCRS. RESULTS: Principal mechanisms for altering inflammation at the systemic level via dietary manipulation center around (1) increased consumption of foods with anti-inflammatory properties, and (2) modulation of the gut microbiome to reduce short-chain fatty acid secretion by dysbiotic gut flora. Recommended dietary modifications to reduce systemic markers of inflammation or to improve RCRS include alteration of macronutrient intake, alterations in consumption of meat and fats, consumption of prebiotics and probiotics, and a low-salicylate diet in the context of aspirin-exacerbated respiratory disease. CONCLUSION: Dietary modifications may offer a potential nonpharmacologic means of reducing inflammation in patients with RCRS and hence may represent a complementary adjunct to existing medical therapies. Additional prospective studies are required to further validate the concept of dietary modifications in patients with RCRS to support the findings.

Gram-negative bacterial carriage in chronic rhinosinusitis with nasal polyposis is not associated with more severe inflammation.

BACKGROUND: We have previously demonstrated that persistent symptoms following functional endoscopic sinus surgery for chronic rhinosinusitis (CRS) is associated with Gram-negative bacterial carriage. Mechanisms for this remain unknown. We wished to determine whether Gram-negative carriage in patients with CRS with nasal polyposis is associated with a more severe inflammatory phenomenon. METHODS: Three hundred and thirty-seven patients with CRS with nasal polyposis (CRSwNP) previously phenotyped for genetic association studies with questionnaire, serum biomarkers, and endoscopically-obtained swab cultures were studied. These were separated according to the presence (wGN) or absence (sGN) of Gram-negative bacterial carriage; demographic parameters and available serum biomarkers (complete blood count [CBC], total immunoglobulin E [IgE]) were then compared. Subgroup analysis for Pseudomonas aeruginosa (GNwPa) and non-Pseudomonas Gram-negative bacteria (GNsPs) was performed in order to explore potentially differential roles of these bacteria. RESULTS: Gram-negative bacterial carriage was not associated with a difference in demographic parameters or serum biomarkers. However, P. aeruginosa carriage was associated with a higher self-reported incidence of asthma (GNwPa 79%, sGN 57%; p = 0.048). Interestingly, serum IgE was increased in the non-Pseudomonas Gram-negative population (GNsPs: 338 IU/mL, sGN: 195 IU/mL; p = 0.026). CONCLUSION: CRSwNP patients colonized with Gram-negative bacteria have a similar pattern of inflammation as assessed by serum biomarkers to those colonized with Gram-positive ones. Gram-negative bacteria may contribute to development of a T helper 2 (Th2) phenotype via other mechanisms, possibly via Toll-like receptor 4 (TLR4)-mediated interleukin 33 (IL-33) production. Differences in phenotype associated with Pseudomonas species carriage suggest a different behavior than other Gram-negative bacteria, supporting their importance as disease modifiers in CRSwNP.

Active smoking status in chronic rhinosinusitis is associated with higher serum markers of inflammation and lower serum eosinophilia.

BACKGROUND: Smoking negatively affects postoperative evolution in patients with chronic rhinosinusitis (CRS); however, the mechanism remains incompletely described. In the lung, smoking increases expression of proinflammatory genes and is associated with an elevation of inflammatory serum markers. Our objective is to determine the impact of smoking on these biomarkers in CRS. METHODS: Two existing populations of patients previously phenotyped for genetic association studies (206 patients with refractory CRS and 408 patients with CRS and nasal polyposis) were stratified according to self-reported smoking status and available serum biomarkers (complete blood count [CBC], total immunoglobulin E [IgE]). Asthma and bacterial cultures were evaluated. RESULTS: Active smoking was low in both groups (genetics of chronic rhinosinusitis 1 [GCRS1]: 11.2%; genetics of chronic rhinosinusitis 2 [GCRS2]: 9.4%). Total white blood cell (WBC) count was significantly higher in active smokers than in those who had never smoked and ex-smokers. Serum eosinophilia and prevalence of self-reported asthma was lower in active smokers than never-smokers. In the GCRS2 population, endoscopically-collected cultures trended toward a lower recovery rate of Staphylococcus aureus in smokers (p = 0.07). Never-smokers and ex-smokers had similar levels of WBCs and eosinophils. CONCLUSION: Our study reveals that active tobacco smoking is associated with increases in markers of systemic inflammation in patients with CRS. The proinflammatory effect of smoking seems not only to act locally on sinus mucosa as previously described, but may also influence levels of inflammatory biomarkers systemically, suggesting that smoking-induced changes have profound implications for health. Nevertheless, these changes may be potentially reversible; thus smoking cessation in CRS patients is strongly advised, and may have an impact on response of CRS to therapy.

Clinical features of cytotoxic CD8+ T-lymphocyte deficiency in chronic rhinosinusitis patients: a demographic and functional study.

BACKGROUND: Identification of Staphylococcus aureus intracellularly in chronic rhinosinusitis (CRS) suggests an underlying cellular immunodeficiency. Supporting this, we have previously reported low CD8+ (cytotoxic) T-lymphocyte levels in a subpopulation of CRS patients and identified polymorphisms in the CD8A gene associated with CRS. In order to better understand the role of low CD8+ in CRS, we wished to determine the phenotype for CRS/Low CD8+ in comparison to that of conventional CRS. METHODS: Sixty-seven low CD8+ CRS patients identified during investigation of CRS were compared for demographics, disease evolution, and bacteriology on endoscopic culture were compared with an existing population of 480 patients with CRS with nasal polyposis previously recruited for genetic association studies. RESULTS: Mean level of CD8+ in the CRS/Low CD8+ population was 0.15 × 10(9)/L (range, 0.20-1.5 × 10(9)/L). There was no difference between both groups in terms of history of allergy, asthma, eczema, acetylsalicylic acid (ASA) intolerance or smoking. The bacteriology was similar between both groups (S. aureus: CRS/Low CD8+: 35%; CRS 32%, p = 0.643). Evolution of disease was somewhat milder in CRS/Low CD8+, with fewer patients requiring surgery, and first surgery performed at a more advanced age. However, antibiotic use was higher in CRS/Low CD8+. Subgroup analysis restricted to CRS with nasal polyposis (CRSwNP)/Low CD8 or CRS without nasal polyposis (CRSsNP)/Low CD8 phenotypes did not substantially alter these results. CONCLUSION: Low CD8+ levels are often identified in CRS patients; however, these patients have disease remarkably similar to those with conventional CRS. This suggests that immune deficiency, whether systemic or locally mediated, is well tolerated and may be present in other forms in CRS. CRS patients with low CD8+ levels may possibly require antibacterial therapies as part of ongoing management.

Polymorphisms in RYBP and AOAH genes are associated with chronic rhinosinusitis in a Chinese population: a replication study.

BACKGROUND: The development of CRS is believed to be the result of combined interactions between the genetic background of the affected subject and environmental factors. OBJECTIVES: To replicate and extend our recent findings from genetic association studies in chronic rhinosinusitis (CRS) performed in a Canadian Caucasian population in a Chinese population. METHODS: In a case-control replication study, DNA samples were obtained from CRS with (n  = 306; CRSwNP) and without (n = 332; CRSsNP) nasal polyps, and controls (n = 315) in a Chinese population. A total of forty-nine single nucleotide polymorphisms (SNPs) selected from previous identified SNPs associated with CRS in Canadian population, and SNPs from the CHB HapMap dataset were individually genotyped. RESULTS: We identified two SNPs respectively in RYBP (rs4532099, p = 2.15E-06, OR = 2.59) and AOAH (rs4504543, p = 0.0001152, OR = 0.58) significantly associated with whole CRS cohort. Subgroup analysis for the presence of nasal polyps (CRSwNP and CRSsNP) displayed significant association in CRSwNP cohorts regarding to one SNP in RYBP (P = 3.24(E)-006, OR = 2.76). Evidence of association in the CRSsNP groups in terms of 2 SNPs (AOAH_rs4504543 and RYBP_rs4532099) was detected as well. Stratifying analysis by gender demonstrated that none of the selected SNPs were associated with CRSwNP as well as CRSsNP. Meanwhile 3 SNPs (IL1A_rs17561, P = 0.005778; IL1A_rs1800587, P = 0.009561; IRAK4_rs4251513, P = 0.03837) were associated with serum total IgE level. CONCLUSIONS: These genes are biologically plausible, with roles in regulation of transcription (RYBP) and inflammatory response (AOAH). The present data suggests the potential common genetic basis in the development of CRS in Chinese and Caucasian population.

Expression of the extracellular matrix gene periostin is increased in chronic rhinosinusitis and decreases following successful endoscopic sinus surgery.

BACKGROUND: The extracellular matrix (ECM) is a potentially important component of mucosal immunity. ECM dysregulation in chronic rhinosinusitis (CRS) is suggested by genomewide association studies identifying ECM genes as top candidates. Further support is afforded by the demonstration of increased expression of periostin (POSTN) in CRS biopsy samples compared to controls, and by reported roles in eosinophilic inflammation and steroid responsiveness. We wished to evaluate the potential utility of POSTN as a biomarker for disease activity by determining whether POSTN levels were modified in disease and whether they were modulated by endoscopic sinus surgery (ESS). METHODS: Twelve patients undergoing ESS for CRS and 10 controls undergoing ESS for skull-base access were recruited. An epithelial sample from the frontal recess was collected using a cytology brush at time of and 3 months after surgery. Microarray analysis of gene expression was performed using the Illumina HumanHT-12 Beadchip v3. POSTN protein level in biopsy samples taken from the same place of brushings at surgery was analyzed by immunohistochemistry (IHC) staining. RESULTS: All patients resolved CRS with ESS. At surgery, a higher expression of POSTN was seen in the CRS group compared to controls (fold change [FC] = 4.89, positive false discovery rate (pFDR) = 0.0006), which was also verified by IHC. After ESS, POSTN expression in CRS group decreased (FC = -3.074, pFDR = 0.0044), and was no longer different from controls (FC = 1.56, pFDR = 0.3). CONCLUSION: Demonstration of reduced levels in the expression of POSTN, an ECM gene, following resolution of disease, implicates POSTN, a potential pathogenesis indicator or biomarker of CRS disease activity and responsiveness to treatment.

Polymorphisms in the nitric oxide synthase 1 gene are associated with severe chronic rhinosinusitis.

BACKGROUND: Nitric oxide (NO), is a biological messenger molecule and a component of innate immunity, with important roles in the regulation of inflammation and in defense against bacterial biofilms. Polymorphisms in genes regulating NO production have the potential for a role in the development of chronic rhinosinusitis (CRS). The purpose of this study was to determine whether polymorphisms in genes regulating NO synthesis are associated with CRS. METHODS: An established population of 206 individuals with severe CRS and 196 postal code-matched controls was previously screened using a pooling genome-wide associations study to estimate allelic frequency. Genes regulating NO synthesis with a maximal probability of association were identified. High-probability single nucleotide polymorphisms SNPs from the NO synthase (NOS1) and its ligand NOS1 adaptor protein (NOS1AP) genes were retained for individual genotyping. PLINK software was used to determine association. RESULTS: Sixteen SNPs were genotyped successfully with a genotype distribution in agreement with Hardy-Weinberg equilibrium. Two SNPs for NOS1 (rs1483757 and rs9658281) were significantly associated with CRS, with a protective effect. The severe subphenotype showed stronger associations. Subgroup analysis for the presence of nasal polyps, origin, and gender did not influence strength of associations. CONCLUSION: These data suggest that polymorphisms in the NOS1 gene may play a role in the susceptibility to develop CRS. Study findings apply to patients with severe CRS, unresponsive to surgery.

c-MET pathway involvement in chronic rhinosinusitis: a genetic association analysis.

OBJECTIVE: The c-MET receptor and its ligand hepatocyte growth factor (HGF) has been shown to be overexpressed in tissue from chronic rhinosinusitis (CRS) patients with nasal polyps compared with that from controls. We assessed the genetic association of polymorphisms in the met proto-oncogene (MET) gene with CRS. STUDY DESIGN: Case-control genetic association study. SETTING: Tertiary-care university hospital. SUBJECTS AND METHODS: A total of 206 unrelated Canadian patients with CRS and 196 control subjects were enrolled. Subjects were genotyped for 33 polymorphisms in the MET gene. RESULTS: The allelic association analysis showed eight single nucleotide polymorphisms in the MET gene (rs38850, rs38855, rs38857, rs2237717, rs2402118, rs193688, rs1621, rs42336) with a statistically significant association with CRS. The rs38850 T allele showed the strongest association and the highest risk for CRS (P = 0.004; odds ratio 1.65, 95% confidence interval 1.18-2.32); the association did not reach statistical significance after adjustment for genomic control (P = 0.06). The haplotype TGG constructed of markers rs38850, rs38855, and rs38857 represented a risk haplotype, resulting in a P value of 0.003 that remained significant after correction for multiple testing (P = 0.018). CONCLUSION: These data suggest that polymorphisms in the MET gene may play a role in the susceptibility to develop CRS. Study findings apply to patients with severe CRS unresponsive to surgery.

Polymorphisms in the SERPINA1 (Alpha-1-Antitrypsin) gene are associated with severe chronic rhinosinusitis unresponsive to medical therapy.

BACKGROUND: Alpha-1-antitrypsin (AAT) is a serine protease inhibitor that blocks the protease, neutrophil elastase. Previous population studies have suggested that heterozygote status for the AAT gene (SERPINA1) is a risk factor for chronic rhinosinusitis with nasal polyposis (CRSwNP). This implies a potential genetic predisposition to CRS tied to AAT deficiency. The purpose of this study was to investigate the association between single nucleotide polymorphisms (SNPs) in the SERPINA1 gene and CRS. METHODS: DNA extracted from a population of 206 patients diagnosed with CRSwNPs and 196 postal code-matched controls was used. A maximally informative set of tagging SNPs from SERPINA1 on chromosome 14q were selected from the HapMap data set (International HapMap Consortium, Nature 437:1299-1320, 2005) and genotyped on the Sequenom platform (Sequenom, San Diego, CA). RESULTS: Successful genotyping was performed for 32 of 33 SNPs. Two SNPs (rs1243168 and rs4900229) located upstream of the SERPINA1gene, were associated with CRS. Individuals homozygous (TT) for these SNPs had an increased probability of having CRS with an odds ratio of 5.95 and 1.49, respectively. Subgroup analysis according to severity of disease identified each SNP to be increasingly common in individuals as disease severity increased (p < 0.001). These individuals were also less likely to be responsive to medical therapy (p < 0.001). CONCLUSION: Polymorphisms of the SERPINA1 gene are associated with clinically severe CRS. These results, from a small subset of individuals with CRS, suggest that defects in AAT may be implicated in a subset of individuals unresponsive to conventional therapy and suggests that alternate therapies may be required for their management.

Evidence of association of interleukin-1 receptor-like 1 gene polymorphisms with chronic rhinosinusitis.

BACKGROUND: Chronic rhinosinusitis (CRS) is a common complex respiratory disease, with a potential genetic component to its development. The protein encoded by the Interleukin-1 receptor-like 1 (IL1RL1) gene is an important effector molecule of T-helper type 2 responses and may potentially be involved in the persistent inflammatory process observed in CRS. We investigated whether certain polymorphisms in the IL1RL1 gene are differentially present in patients with surgery-unresponsive CRS and in control subjects. METHODS: DNA extracted from an existing population of 206 adult patients with surgery-unresponsive CRS and 196 postal-code-matched controls was used. A set of 15 tagging single nucleotide polymorphisms (SNPs) was selected from the HapMap data set and genotyped. DNA sequencing was performed in a subgroup of 15 CRS patients. RESULTS: Statistically significant allelic associations with CRS were noted for 5 SNPs (rs10204137, p = 0.04; rs10208293, p = 0.03; rs13431828, p = 0.008; rs2160203, p = 0.03, and rs4988957, p = 0.03). The analysis showed a consistent significant protective effect against CRS for all the SNPs, yielding an odds ratio (OR) ranging from 0.56 to 0.72. The loci rs13431828 showed the highest association with CRS (p = 0.008; OR = 0.56; 95% CI, 0.36-0.86). A subanalysis revealed that the observed associations were stronger among patients with more severe disease. Sequencing identified five additional known nonsynonymous coding SNPs in linkage disequilibrium with genotyped SNPs. CONCLUSION: Pending replication of these results, this study suggests that polymorphisms within the IL1RL1 gene may be associated with CRS, conferring a protective effect, particularly among those with severe disease.