Russell S. Traister

A Novel Scoring System to Distinguish Vocal Cord Dysfunction From Asthma

BACKGROUND Vocal cord dysfunction is often misdiagnosed and mistreated as asthma, which can lead to increased and unnecessary medication use and increased health care utilization. OBJECTIVE To develop a valid scoring index that could help distinguish vocal cord dysfunction from asthma. METHODS We compared the demographics, comorbidities, clinical symptoms, and symptom triggers of subjects with vocal cord dysfunction (n = 89) and those with asthma (n = 59). By using multivariable logistic regression, we identified distinguishing features associated with vocal cord dysfunction, which were weighted and used to generate a novel score. The scoring index also was tested in an independent sample with documented vocal cord dysfunction (n = 72). RESULTS We identified symptoms of throat tightness and dysphonia, the absence of wheezing, and the presence of odors as a symptom trigger as key features of vocal cord dysfunction that distinguish it from asthma. We developed a weighted index based on these characteristics, the Pittsburgh Vocal Cord Dysfunction Index. By using a cutoff of ≥4, this index had good sensitivity (0.83) and specificity (0.95) for the diagnosis of vocal cord dysfunction. The scoring index also performed reasonably well in the independent convenience sample with laryngoscopy-proven vocal cord dysfunction and accurately made the diagnosis in 77.8% of subjects. CONCLUSION The Pittsburgh Vocal Cord Dysfunction Index is proposed as a simple, valid, and easy-to-use tool for diagnosing vocal cord dysfunction. If confirmed by a prospective evaluation in broader use, it may have significant clinical utility by facilitating a timely and accurate diagnosis of vocal cord dysfunction, thereby preventing misdiagnosis and mistreatment as asthma. Future prospective validation studies will need to be performed.

Phenotypic and genotypic association of epithelial IL1RL1 to human TH2-like asthma

BACKGROUND Severe asthma remains poorly characterized, although it likely consists of at least 1 phenotype with features of TH2-like inflammation. IL1RL1, encoding both the IL-33 receptor, ST2L, and decoy receptor, sST2, has been genetically associated with asthma, though the mechanism for susceptibility remains unknown. OBJECTIVE Given previous data supporting a role for IL1RL1 in TH2 inflammation, we hypothesized that ST2L expression might be increased in TH2-like asthma and that expression levels would be associated with single nucleotide polymorphisms in IL1RL1, possibly explaining its genetic relationship with asthma. We also sought to evaluate the regulation of ST2L and sST2 in vitro. METHODS Endobronchial brushings and biopsies were obtained and expression of ST2L compared by severity levels, as well as by TH2-like biomarkers. Subjects were genotyped and the relationship of dichotomous expression of ST2L and sST2 to single nucleotide polymorphisms in IL1RL1 were determined. Epithelial cells were grown in air-liquid interface culture, and ST2L and sST2 responses to IFN-γ and IL-13 were evaluated. RESULTS ST2L expression was increased in severe asthma (P = .02) and associated with multiple indicators of TH2-like inflammation, including blood eosinophils (P = .001), exhaled nitric oxide (P = .003), and epithelial CLCA1 (P < .0001) and eotaxin-3 (P = .001) mRNA expression. Multiple single nucleotide polymorphisms in IL1RL1 were found in relation to dichotomous expression of both ST2L and sST2. sST2 expression was associated with IFN-γ expression in bronchoalveolar lavage, while inducing its expression in vitro in primary human epithelial cells. CONCLUSION Both pathologic and genetic approaches support a role for IL1RL1 in severe asthma, as well as TH2-lke asthma, suggesting that targeting this pathway may have therapeutic benefits.

The morbidity and cost of vocal cord dysfunction misdiagnosed as asthma.

BACKGROUND Vocal cord dysfunction (VCD) is frequently misdiagnosed and mistreated as asthma, which leads to morbidity secondary to unnecessary medication use and increased health care utilization. OBJECTIVE We identified discriminating symptoms and triggers, and analyzed the costs, morbidity, and health care burden associated with misdiagnosis of VCD as asthma. We sought to determine if current measures of asthma control contributed to these findings. We evaluated if a simple set of breathing exercises would be an effective low-cost treatment option for those with VCD. METHODS We compared the demographics, comorbidities, clinical symptoms, and symptom triggers of subjects with VCD misdiagnosed as asthma compared with those not misdiagnosed as asthma. Costs secondary to asthma misdiagnosis were quantified, and the effectiveness of breathing exercises as a treatment option was evaluated. RESULTS We identified symptoms of shortness of breath, wheezing, chest tightness, and a trigger of exercise as being more common in the subjects with VCD misdiagnosed as asthma. Asthma medication use and health care utilization and costs were also higher in this group. The subjects with VCD had Asthma Control Questionnaire scores that labelled them as having uncontrolled asthma. Breathing exercises appeared to offer an inexpensive and effective treatment option for subjects with VCD. CONCLUSION Misdiagnosis of VCD as asthma leads to significant morbidity and increased costs, and misuse of measures of asthma control may be contributing to these findings. Timely and accurate diagnosis of VCD and the use of breathing exercises have the potential to eliminate or minimize the burdens on the patient and the health care system.

Gene therapy for arthritis

Arthritis is among the leading causes of disability in the developed world. There remains no cure for this disease and the current treatments are only modestly effective at slowing the diseases progression and providing symptomatic relief. The clinical effectiveness of current treatment regimens has been limited by short half-lives of the drugs and the requirement for repeated systemic administration. Utilizing gene transfer approaches for the treatment of arthritis may overcome some of the obstacles associated with current treatment strategies. The present review examines recent developments in gene therapy for arthritis. Delivery strategies, gene transfer vectors, candidate genes, and safety are also discussed.

A retrospective analysis comparing subjects with isolated and coexistent vocal cord dysfunction and asthma.

Vocal cord dysfunction (VCD) is often misdiagnosed as asthma or complicates coexisting asthma. This study aimed to identify distinguishing clinical characteristics in patients with VCD, asthma, and coexisting VCD and asthma. We conducted a retrospective analysis of demographic and clinical data from 292 patients with VCD, asthma, coexisting VCD and asthma, and control subjects from an outpatient university asthma/allergy clinic. Concomitant asthma was present in 32.6% of VCD subjects. Overall, 42.4 % of all VCD subjects were previously misdiagnosed as having asthma for an average of 9.0 years. Upper airway symptoms were more prevalent in the VCD population and nocturnal apnea was more prevalent in comorbid VCD and asthma compared with either condition alone. Irritable bowel syndrome and chronic pain were identified as new comorbidities associated with VCD. VCD subjects who had been misdiagnosed with asthma had significantly more health care and asthma medication use compared to VCD subjects who had not mimicked asthma. There was no difference in asthma severity between those with and without VCD. Comorbid VCD and asthma led to an increase in long-acting β-agonist use only, but no difference in health care usage, compared with asthma alone. These findings suggest that the main morbidity associated with VCD may not lie in its inherent disease process, but instead in its ability to mimic asthma.

Focal Adhesion Kinase–Mediated Activation of Glycogen Synthase Kinase 3β Regulates IL-33 Receptor Internalization and IL-33 Signaling

IL-33, a relatively new member of the IL-1 cytokine family, plays a crucial role in allergic inflammation and acute lung injury. Long form ST2 (ST2L), the receptor for IL-33, is expressed on immune effector cells and lung epithelia and plays a critical role in triggering inflammation. We have previously shown that ST2L stability is regulated by the ubiquitin-proteasome system; however, its upstream internalization has not been studied. In this study, we demonstrate that glycogen synthase kinase 3β (GSK3β) regulates ST2L internalization and IL-33 signaling. IL-33 treatment induced ST2L internalization, and an effect was attenuated by inhibition or downregulation of GSK3β. GSK3β was found to interact with ST2L on serine residue 446 in response to IL-33 treatment. GSK3β binding site mutant (ST2LS446A) and phosphorylation site mutant (ST2LS442A) are resistant to IL-33–induced ST2L internalization. We also found that IL-33 activated focal adhesion kinase (FAK). Inhibition of FAK impaired IL-33–induced GSK3β activation and ST2L internalization. Furthermore, inhibition of ST2L internalization enhanced IL-33–induced cytokine release in lung epithelial cells. These results suggest that modulation of the ST2L internalization by FAK/GSK3β might serve as a unique strategy to lessen pulmonary inflammation.

Retrovirus-induced spongiform neurodegeneration is mediated by unique central nervous system viral targeting and expression of env alone.

ABSTRACT Certain murine leukemia viruses (MLVs) can induce progressive noninflammatory spongiform neurodegeneration similar to that caused by prions. The primary MLV determinants responsible have been mapped to within the env gene; however, it has remained unclear how env mediates disease, whether non-Env viral components are required, and what central nervous system (CNS) cells constitute the critical CNS targets. To address these questions, we examined the effect of transplanting engraftable C17.2 neural stem cells engineered to pseudotype, disseminate, and trans-complement neurovirulent (CasBrE, CasE, and CasES) or non-neurovirulent (Friend and SFF-FE) env sequences (SU or SU/TM) within the CNS using either the “non-neurovirulent” amphotropic helper virus, 4070A, or pgag-polgpt (a nonpackaged vector encoding Gag-Pol). These studies revealed that acute MLV-induced spongiosis results from two separable activities of Env. First, Env causes neuropathology through unique viral targeting within the CNS, which was efficiently mediated by ecotropic Envs (CasBrE and Friend), but not 4070A amphotropic Env. Second, Env induces spongiosis through a toxin activity that is MLV-receptor independent and does not require the coexpression of other viral structural proteins. CasBrE and 4070A Envs possess the toxin activity, whereas Friend Env does not. Although the identity of the critical viral target cell(s) remains unresolved, our results appear to exclude microglia and oligodendrocyte lineage cells, while implicating viral entry into susceptible neurons. Thus, MLV-induced disease parallels prionopathies in that a single protein, Env, mediates both the CNS targeting and the toxicity of the infectious agent that manifests itself as progressive vacuolar neurodegeneration.

Revisiting fatal asthma

Severe asthma affects up to 10% of the asthma population and inhibition of CD8þ T cells attenuated respiratory syncytial remains poorly understood with few therapeutic options. Unfortunately, asthma deaths still occur, yet the reasons why some patients succumb to asthma compared with others is unknown. Given that many phenotypes of asthma have now been described, it is likely that different mechanisms may lead to death in select subgroups of asthmatics. Those with virallyeinduced exacerbations may have more prominent mediators of innate inflammation, including neutrophils, while those with other triggers, including allergens, with or without infections, demonstrate more prominent eosinophilia.1 In this issue of the Annals of Allergy Asthma and Immunology, Oda et al. describe a novel association of increased interleukin (IL)-18 and IL-18 receptor expression in inflammatory cells, epithelial cells, and smooth muscle in nonsmoking subjects with fatal asthma, as compared with those with mild asthma and controls.2 Consistent with prior studies of fatal asthma, they also observed evidence of severe airway remodeling, including mucus plugging, goblet cell hyperplasia, smooth muscle hypertrophy, submucosal gland hyperplasia, basement membrane thickening, and eosinophilic inflammation. The authors note that similar to a few earlier reports, they found a marked increase in CD8þ T cells in fatal asthma, ultimately theorizing that IL-18 may activate CD8þ T cells in subjects with severe asthma, potentially leading to a fatal outcome. Neutrophilic inflammation was notably similar between those with fatal asthma and mild asthma. Perhaps the most novel aspect to their study was an increase in IL-18 positive cells. IL-18 was initially described as an IFNginducing cytokine, though it has also been demonstrated to affect Type-2 cytokine expression (by T cells, natural killer cells, mast cells, and basophils) and immunoglobulin E production. It is primarily produced by macrophages, but T cells, B cells and epithelial cells, among others, have also been demonstrated to produce IL-18.3 Models of asthma in IL-18 deficient mice have less airway remodeling and inflammation, while increased IL-18 expression is associated with increased airway inflammation and hyper responsiveness.4 In humans, serum IL-18 levels were shown to be significantly higher in association with an acute exacerbation in mild-moderate asthmatic patients.5 Further, polymorphisms in the IL-18 receptor have been consistently associated with asthma in multiple genome wide association studies.6 Yet the mechanisms by which IL-18 worsens asthma remains poorly understood. While the link between IL-18 and asthma risk and severity, although small, has been quite consistent, the role of CD8þ Tcells in asthma is still not entirely clear. CD8þ memory T cells inhibited allergic sensitivity in mice in one study, yet in another mouse study

A 10-year experience of a novel and safe modified environmental rush immunotherapy protocol.

BACKGROUND Allergen immunotherapy (AIT) is an effective treatment option for allergic rhinitis. Although conventional AIT takes 6 months to reach maintenance dosing, rush AIT accelerates the build-up period and reaches the maintenance dose months earlier. However, accelerated schedules of AIT carry an increased risk of systemic reactions (SR). OBJECTIVE We aimed to describe a novel 1-day, eight-step modified environmental rush immunotherapy (MERIT) protocol, characteristics of the patients who underwent this therapy, and the safety of this procedure. We also compared distinguishing features of those patients with SRs. METHODS We retrospectively analyzed demographic and clinical data of 362 adult patients seen in an outpatient university allergy clinic, from January 2005 to January 2015, and who underwent MERIT protocol treatment for allergic rhinitis. RESULTS In a univariate analysis, the factors significantly associated with SR were lower body mass index (BMI); younger age; a higher number of allergens in the extracts; and the presence of cat, dust mite, and certain weed pollens. In a multivariate analysis, cat, dust mite, and mugwort were significantly associated with SRs. Over the 10-year period, 50 patients experienced SRs (13.81%), with a total number of 68 SRs. Only 4.7% of the SRs occurred on the MERIT day. Most SRs occurred >30 minutes and were mild. Our MERIT protocol continuation rate for all the patients was 49.2% and did not seem to be influenced by having an SR versus no SR. CONCLUSION We present a modified rush AIT protocol that seems to be effective and safe. Most patients tolerated therapy, and only a minority of patients developed SRs, which generally were mild. We identified novel risk factors for SRs that may help determine optimal dosing to decrease the risk of SRs. Ultimately, future studies will be needed to compare the safety of our MERIT protocol with traditional AIT.