Association Between Elevated Blood Eosinophils and Chronic Kidney Disease Progression: Analyses of a Large United States Electronic Health Records Database.

Background: Blood eosinophils can increase in response to infection, inflammation, and hypersensitivity reactions, yet their involvement in the progression of chronic kidney disease (CKD) is poorly understood. This study explores the relationship between blood eosinophils and CKD progression among patients in a real-world setting. Methods: This retrospective study analyzed data obtained from the Optum® de-identified electronic health records dataset in the United States. Patients diagnosed with CKD stage 3 or 4 (International Classification of Diseases diagnosis code or estimated glomerular filtration rate [eGFR] <60 mL/min) between January 2011 and March 2018 were included and followed until progression to the next CKD stage, death, or dropout. The primary objective of this study was to assess the relationship between blood eosinophil counts (bEOS) and CKD progression, adjusting for clinical and demographic features as well as known risk factors for CKD stages 3-4. The primary outcomes were CKD progression and all-cause mortality. Results: We found that high eosinophilic levels (bEOS ≥300 cells/µL) were associated with CKD progression from stage 3 to stages 4 or 5 (hazard ratio [HR] ranging from 1.30 to 1.50) and from stages 4 to 5 (HR ranging from 1.28 to 1.50). Among patients with CKD progression, those with blood eosinophils ≥300 cells/µL appeared to have a relatively lower eGFR, higher all-cause mortality, and reduced time to CKD progression and death than those with <300 cells/µL. Factors including sex, race, hypertension, anemia, and treatments for cardiovascular and hematopoietic drugs were associated with CKD progression. Conclusion: Elevated eosinophils may increase the risk for CKD progression. Larger studies are needed to assess whether the risk of mortality is increased among patients with elevated eosinophils.

Clinical and economic burden of chronic rhinosinusitis with nasal polyposis: A U.S. administrative claims analysis.

Background: Limited data exist on the clinical and economic burden of chronic rhinosinusitis with nasal polyposis (CRSwNP). Objective: To describe patient characteristics, health-care resource utilization (HCRU), and health-care costs among patients with CRSwNP with and without comorbid asthma (primary analysis) and with surgical management of nasal polyps (secondary analysis). Methods: This was a retrospective study of patients diagnosed with CRSwNP conducted using administrative claims data from January 1, 2013, through March 31, 2019. Study outcomes were assessed over a 2-year follow-up. Results were stratified by baseline asthma status (primary analysis) and presented separately for patients with surgically managed CRSwNP (secondary analysis). Results: The primary analysis included 10,999 patients with CRSwNP (2649 with asthma, 8350 without asthma). Patients with versus without asthma had higher medication use, HCRU, and all-cause medical costs (mean ± standard deviation $34,667 ± $42,234 versus $27,122 ± $45,573; p < 0.001) across the full follow-up period. CRSwNP-related medical costs were significantly higher for patients with versus without asthma in year 2 of follow-up. In the surgical management analysis (n = 4943), most categories of medication use and CRSwNP-related HCRU declined from baseline levels during follow-up, and CRSwNP-related pharmacy costs in year 2 were less than half of baseline levels. Conclusion: Patients diagnosed with CRSwNP and asthma had a greater burden of illness than those without asthma. Higher CRSwNP-related medical costs in year 2 of follow-up for patients with asthma may indicate worsening symptoms over time. Among patients with surgically managed CRSwNP, HCRU and costs increased in year 1 of follow-up but decreased below baseline levels in year 2, potentially reflecting improved symptom severity.

Effects of Reslizumab on Asthma Outcomes in a Subgroup of Eosinophilic Asthma Patients with Self-Reported Chronic Rhinosinusitis with Nasal Polyps.

BACKGROUND: An estimated 7% of patients with asthma have chronic rhinosinusitis with nasal polyps (CRSwNP), and more than 80% have at least some radiographic evidence of sinonasal inflammation. Aspirin sensitivity is strongly associated with elevated blood eosinophil levels and increased asthma severity. Intravenous (IV) reslizumab has been shown to improve asthma control in patients with nasal polyps. OBJECTIVE: These post hoc analyses of pooled data from 2 BREATH phase 3 clinical trials, studies 1 and 2 (NCT01287039 and NCT01285323), examined asthma-related outcomes in patients with comorbid, self-reported CRSwNP with and without aspirin sensitivity. METHODS: Patients aged 12-75 years with elevated blood eosinophils (≥400 cells/µL) and inadequately controlled asthma were randomized to receive placebo or reslizumab (3 mg/kg IV) every 4 weeks for 52 weeks. Patients continued their background asthma maintenance therapy during the study. Information regarding the presence of CRSwNP was obtained through patient-reported medical history. RESULTS: Add-on reslizumab treatment reduced the frequency of clinical asthma exacerbations by 83% versus placebo among patients with CRSwNP. Among patients with and without aspirin sensitivity, reductions of 79% and 84%, respectively, were observed. Patients with CRSwNP (with and without aspirin sensitivity) treated with reslizumab add-on therapy also had significant improvements in lung function, as measured by forced expiratory volume in 1 second, compared with placebo. Among patients with CRSwNP, reslizumab was also associated with improvements in patient-reported asthma control and asthma quality of life. CONCLUSIONS: Patients with eosinophilic asthma and self-reported CRSwNP, with and without aspirin sensitivity, are highly responsive to treatment with reslizumab for asthma-related outcomes. These findings suggest that prospective investigation of reslizumab in this patient population is warranted.

Chronic Rhinosinusitis and Aspirin-Exacerbated Respiratory Disease.

Patients with severe asthma and concomitant chronic rhinosinusitis often have severe, refractory upper and lower airway inflammation. This inflammation has been proposed to be similar throughout the upper and lower airways leading to the unified airways concept. This article reviews chronic rhinosinusitis with and without nasal polyps, and the subgroup with aspirin-exacerbated respiratory disease, while focusing on the relationship with asthma. Additionally, diagnosis and treatment with current and newer therapies are discussed.

Clinical Examination of Tissue Eosinophilia in Patients with Chronic Rhinosinusitis and Nasal Polyposis.

OBJECTIVE: (1) Describe clinical and histopathologic findings in patients with chronic rhinosinusitis with nasal polyps (CRSwNP). (2) Determine if tissue and serum eosinophilia predicts disease severity in CRSwNP. STUDY DESIGN: Case series with chart review. SETTING: Academic hospital specializing in respiratory and allergic disease. SUBJECTS: Patients with CRSwNP treated from 2008 to 2010. METHODS: Clinical data were collected; sinus computed tomography (CT) scans were scored according to the Lund-Mackay system; and surgical specimens were evaluated for degree of tissue eosinophilia. Statistical analysis was performed to compare eosinophilia with indicators of disease severity. RESULTS: Seventy CRSwNP patients were included, with a mean Lund-Mackay score of 16.7; 62.1% of patients had severe asthma, and 62.9% were aspirin sensitive. Elevated tissue eosinophil level did not correlate with medication usage, olfactory symptoms, or Lund-Mackay scores, nor did it correlate with presence of asthma or aspirin-sensitivity (P = .09). Patients with mild asthma had significantly more tissue eosinophils versus patients with severe asthma, possibly because of the high amount of chronic corticosteroid use in severe asthmatics. There was no correlation between tissue and serum eosinophil counts (P = .97), but there was a significant positive correlation between CT score and peripheral eosinophil level (P < .05). CONCLUSIONS: Higher serum eosinophil levels may indicate more extensive mucosal disease as measured on CT scan. Neither serum nor tissue eosinophilia predicted disease severity in our retrospective analysis of CRSwNP patients, and serum eosinophil level did not serve as a marker of tissue eosinophilia.

Progressive Multifocal Leukoencephalopathy in Primary Immune Deficiencies: Stat1 Gain of Function and Review of the Literature.

BACKGROUND: Progressive multifocal leukoencephalopathy (PML) is a rare, severe, otherwise fatal viral infection of the white matter of the brain caused by the polyomavirus JC virus, which typically occurs only in immunocompromised patients. One patient with dominant gain-of-function (GOF) mutation in signal transducer and activator of transcription 1 (STAT1) with chronic mucocutaneous candidiasis and PML was reported previously. We aim to identify the molecular defect in 3 patients with PML and to review the literature on PML in primary immune defects (PIDs). METHODS: STAT1 was sequenced in 3 patients with PML. U3C cell lines were transfected with STAT1 and assays to search for STAT1 phosphorylation, transcriptional response, and target gene expression were performed. RESULTS: We identified 3 new unrelated cases of PML in patients with GOF STAT1 mutations, including the novel STAT1 mutation, L400Q. These STAT1 mutations caused delayed STAT1 dephosphorylation and enhanced interferon-gamma-driven responses. In our review of the literature regarding PML in primary immune deficiencies we found 26 cases, only 54% of which were molecularly characterized, the remainder being syndromically diagnosed only. CONCLUSIONS: The occurrence of PML in 4 cases of STAT1 GOF suggests that STAT1 plays a critical role in the control of JC virus in the central nervous system.

Characterization and treatment of patients with chronic rhinosinusitis and nasal polyps.

BACKGROUND: Patients with chronic rhinosinusitis (CRS) and nasal polyps (NPs) may be subdivided into aspirin-sensitive (AS) and aspirin-tolerant (AT) populations. These cohorts are not well characterized. OBJECTIVE: To examine phenotypic characteristics and determine the extent of medical/surgical interventions in patients with CRS+NP and to compare the AS with the AT subset in the CRS+NP sample. METHODS: Retrospective chart review was performed at a tertiary academic respiratory hospital. Data included patient demographics, asthma severity, peripheral eosinophilia, Lund-Mackay computed tomographic score, symptomatic dysosmia, and therapeutic interventions. RESULTS: Of the 182 patients included, 81 had aspirin sensitivity (45%) and 101 had aspirin tolerance (55%). Asthma was present in 94% of patients with CRS+NP (100% in AS subgroup vs 89% in AT subgroup, P = .001). Eighty-eight percent of the CRS+NP sample had moderate to severe persistent asthma. In the AS and AT subgroups, asthma severity was similar (P > .6). The CRS+NP sample showed a mean computed tomographic score of 14.0 (44% with eosinophilia and 46% with dysosmia). More severe sinus disease was noted in the AS group (Lund-Mackay computed tomographic scores, P = .002; olfactory symptoms, P = .001). Serum eosinophil levels were not statistically different between groups (51% in AS group, 39% in AT group, P > .1). CONCLUSION: This study is one of the broadest reviews of patients with CRS+NP, with unique findings in the high prevalence of asthma in AS and AT patients, greater olfactory dysfunction in AS patients, and a minority of patients with CRS+NP and circulating eosinophils. Most AS patients do not have increased circulating eosinophils, as is often believed. These results shed further light on the association between asthma and upper respiratory tract disease in those with nasal polyposis.

Variations in expression of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 in nasal mucosa of aspirin-sensitive versus aspirin-tolerant patients with nasal polyposis.

BACKGROUND: Matrix metalloproteinases (MMPs) are key enzymes responsible for extracellular matrix degradation contributing to the progressive histological changes seen in lower airway disease, including asthma. MMP-9 and TIMP-1 have also shown some role in the pathogenesis of chronic rhinosinusitis (CRS) and nasal polyposis (NP). OBJECTIVE: We aim to determine variability in expression of MMP-9 and its inhibitor, tissue inhibitor of metalloproteinase-1 (TIMP-1), in sinus tissue from distinct patient populations presenting with nasal polyposis. METHODS: The expression of MMP-9 and TIMP-1 was investigated in nasal polyp tissue from 6 aspirin-sensitive (AS) and 6 aspirin-tolerant (AT) patients undergoing endoscopic sinus surgery for chronic rhinosinusitis with nasal polyposis (CRSwNP). Sinus mucosa from 6 patients with chronic rhinosinusitis without nasal polyposis (CRSsNP) was used as control. The MMP-9 and TIMP-1 expression was measured using immunofluorescence technique and graded using manual and computerized methods. RESULTS: Expression of TIMP-1 was significantly reduced in the AS group when compared with both the AT and CRSsNP (control) groups (P < .001). The MMP-9/TIMP-1 ratio was significantly increased in the AS group when compared with other patient groups (P < .001). The MMP- 9 expression was similar between study and control groups. CONCLUSION: These results support the importance of MMP-9 and TIMP-1 expression in nasal polyp formation. The decreased expression of TIMP-1 in AS patients may promote the effects of MMP-9 expression and thus contribute to tissue remodeling and inflammatory changes. This finding may lead to further understanding of disease severity and resistance to treatment in this group of patients, as well as the pathogenesis of nasal polyps.

The effect of aspirin desensitization on novel biomarkers in aspirin-exacerbated respiratory diseases.

BACKGROUND: Patients with aspirin-exacerbated respiratory disease have been shown to benefit clinically from aspirin desensitization followed by chronic high-dose aspirin therapy. However, the mechanism of this phenomenon is still unclear. OBJECTIVE: The aim of this study was to characterize the airway inflammatory response to aspirin desensitization and after treatment with high-dose aspirin for 6 months. METHODS: Twenty-one adult patients with asthma, chronic polypoid sinusitis, and a convincing history of acute respiratory reaction to the ingestion of aspirin or nonsteroidal anti-inflammatory drugs were selected. These patients underwent an oral desensitization to aspirin over a 2-day period, followed by daily ingestion of aspirin 650 mg twice daily. Induced sputum samples and exhaled nitric oxide measurements were taken before the procedure, during the second day of the procedure, and after 6 months of treatment. RESULTS: There was a significant elevation in both the exhaled nitric oxide level (P = .03) and sputum tryptase level (P = .05) during the desensitization process. After 6 months of aspirin treatment, sputum IL-4 (P = .0007) and matrix metalloproteinase 9 (MMP-9; P = .05) decreased significantly compared with baseline. Predesensitization to postdesensitization changes in MMP-9 and tissue inhibitors of metalloproteinases 1 were highly correlated (r = 0.79; P = .0003). Immediately after the desensitization, MMP-9 and tryptase were correlated (r = 0.82; P = .001), whereas IL-4 was inversely related with FMS-like tyrosine kinase 3 ligand (FLT3-L) (r = -0.79; P = .0008). There was a significant decrease in the average symptom score at 6 months. CONCLUSION: Consistent with previous reports, acute aspirin desensitization in patients with aspirin-exacerbated respiratory disease involves mast cell degranulation. In contrast, long-term treatment with aspirin involves suppression of IL-4 as well as downregulation of proinflammatory MMP-9 while T(H)1 marker FLT3-L increases.

Safety of binodenoson, a selective adenosine A2A receptor agonist vasodilator pharmacological stress agent, in healthy subjects with mild intermittent asthma.

BACKGROUND: The pharmacological stress agents adenosine and dipyridamole are contraindicated in asthma patients because of the risk of adenosine receptor-mediated bronchospasm. Binodenoson, a selective adenosine A(2A) receptor agonist, produces maximal coronary hyperemia during pharmacological stress testing yet has a low affinity for the adenosine A(1), A(2B), and A(3) receptors that are probably responsible for bronchospasm. This study was conducted to assess the safety of binodenoson in 87 healthy young adult volunteers with documented mild, intermittent asthma. METHODS AND RESULTS: This study consisted of a dose-escalating, single-blinded phase and a placebo-controlled, double-blinded phase conducted in healthy, young adults with documented mild, intermittent, asthma. In the single-blinded phase, 3 sequential cohorts of 8 subjects received intravenous binodenoson (0.5, 1.0, and 1.5 microg/kg). In the double-blinded phase, commenced after medical review of results from the single-blinded phase, subjects were randomly assigned 2:1 to either binodenoson 1.5 microg/kg (n=41) or placebo (n=22). The primary end point was clinically significant bronchoconstriction, defined as a decrease in forced expiratory volume in 1 second of >/=20% from the preinjection measure. Secondary safety end points were changes from preinjection measure in forced expiratory volume in 1 second, forced vital capacity, and forced expiratory flow during the middle 50% of the forced vital capacity; vital signs; pulse oximetry; and adverse events. Binodenoson caused no clinically significant bronchoconstriction or alterations in pulmonary function parameters and transiently increased heart rate and systolic blood pressure. The most common treatment-emergent adverse events were tachycardia, dizziness, and flushing. CONCLUSIONS: Binodenoson was safe, well tolerated, and caused no clinically significant bronchoconstriction or pulmonary responses in a small population of healthy subjects with mild, intermittent asthma.

Exhaled nitric oxide identifies the persistent eosinophilic phenotype in severe refractory asthma.

BACKGROUND: The fractional concentration of exhaled nitric oxide (FENO) is increased in asthma, correlates with eosinophilic inflammation, and decreases after steroid therapy. OBJECTIVE: We sought to examine whether persistent eosinophilia would be accompanied by an increased FENO level despite steroid therapy in patients with severe refractory asthma (SRA) as manifestations of steroid resistance. METHODS: Subjects with SRA, subjects with mild-moderate asthma, and healthy control subjects had FENO measured, followed by endobronchial biopsy and bronchoalveolar lavage. Tissue and bronchoalveolar lavage inflammatory cells were assessed for all subjects, and eosinophil status (EOS+/EOS-) was determined for subjects with SRA. RESULTS: Twenty-four subjects with SRA, 15 subjects with moderate-mild asthma, and 17 healthy control subjects were studied. Subjects with EOS+ SRA had significantly higher median FENO levels compared with levels in subjects with EOS- SRA (P = .0084) and all other groups. In subjects with SRA, FENO levels correlated with tissue eosinophils (r(s) = 0.54, P = .007), lymphocytes (r(s) = 0.40, P = .003), and mast cells (r(s) = 0.44, P = .05). FENO levels of greater than 72.9 ppb were associated with a sensitivity of 0.56 and a specificity of 1.0 for EOS+ status in subjects with SRA. CONCLUSION: FENO measurement identified the subgroup of subjects with SRA with persistent eosinophilia despite steroid therapy. Further studies are needed on the use of FENO to monitor response to therapy over time in subjects with SRA.

Cockroach allergy.

The ubiquitous existence of cockroaches and the large-scale domestic infestation seen in inner cities make cockroach proteins a significant indoor allergen and a risk factor for asthma among inner-city residents. Studies have shown that early exposure to high levels of allergen may lead to the development of asthma in individuals with a genetic predisposition to asthma. Although field trials at cockroach abatement do not yield promising results, integrated pest management still remains the best control strategy. In highly susceptible or symptomatic patients, allergen-specific immunotherapy may be beneficial, although data are limited. As molecular techniques improve and recombinant allergens are developed, a more novel form of T-cell-specific immunotherapy may prove to be efficacious without the anaphylactic side effects seen with traditional allergy vaccines.

Deleterious effects of electron beam radiation on allergen extracts.

BACKGROUND: The recent threat to the public posed by the dissemination of Bacillus anthracis through the US postal system has resulted in increased security measures, including electron beam irradiation for the sterilization of some mail. The deleterious effects of electron beam radiation on biological products are not fully understood. OBJECTIVE: The purpose of this investigation was to assess the effect of electron beam radiation, as currently used to sterilize packages and mail in the United States, on several standardized or characterized allergen extracts. METHODS: Selected irradiated extracts were analyzed for allergen content and potency by SDS-PAGE, immunoblot, and ELISA (including inhibition) and compared with untreated extracts. RESULTS: The compositions and immunochemical potencies of these products were altered significantly by irradiation treatment. Physical changes to native protein structures observed after electrophoretic separations coincided with near-complete loss of allergenic and antigenic epitopes present on major and minor allergens, according to ELISA and immunoblot comparisons with untreated extracts. CONCLUSIONS: These results indicate that extracts subjected to electron beam sterilization conditions are likely to contain modified component structures and properties that might compromise the clinical effectiveness of these products.