Local specific Immunoglobulin E among patients with nonallergic rhinitis: a systematic review.

BACKGROUND: Allergen specific immunoglobulin can be present in the nasal mucosa of patients with non-allergic rhinitis (NAR). This condition is defined as local allergic rhinitis. However, the reported presence of nasal specific immunoglobulin E (nspIgE) among NAR is variable. The aim of this review was to summarize the studies which reported the presence of nspIgE among patients diagnosed as NAR. METHODS: Embase (1947- ) and Medline (1946-) were searched until 6th June 2017. A search strategy was utilized to identify studies on nspIgE among patients with NAR. The target population was patients with symptoms of rhinitis, but negative systemic allergen sensitization. Studies with original data on detectable nspIgE among the NAR population were included. Meta-analysis of single proportions as a weighted probability %(95%CI) was performed. Heterogeneity was explored amongst studies. RESULTS: A search strategy returned 2286 studies and 21 were included. These studies involved 648 participants with NAR. NspIgE was detected using either; 1. nasal secretions, 2. epithelial mucosa sampling, 3. tissue biopsies or 4. In-situ tests. Metaanalysis was performed on studies with nasal secretions. The weighted proportion of detectable nspIgE in nasal secretions within patients with NAR was 10.2 (7.4-13.4) %. Population definitions partly explained variability. Detection of nspIgE was lower in patients without a history suggestive of allergy compared to those with a positive allergic history (0 (0-3.1) % v 19.8 (14.5-25.6) %, p<0.01). CONCLUSION: NAR with positive allergy history suggests presence of nspIgE. These patients warrant further allergology evaluation to confirm localized nasal allergy, as they benefit from allergy therapy such as immunotherapy.

Turbinate-Specific IgE in Normal and Rhinitic Patients.

BACKGROUND: Specific immunoglobulin E (sIgE) within the nasal airway is likely to be the most ideal marker of allergic status, but little is known of the normative values in asymptomatic patients and those with rhinitis. OBJECTIVE: The aim of this study was to assess the diagnostic characteristics of inferior turbinate tissue biopsy sIgE in asymptomatic and rhinitic patients. METHODS: A diagnostic cross-sectional study was undertaken, involving patients who underwent inferior turbinate surgery with or without other surgical interventions. Inferior turbinate tissue biopsy was performed during surgery and was assessed for allergen sIgE (dust mite, grass [temperate or subtropical], and animal epithelium) using an automated immunoassay. Tissue sIgE was assessed among asymptomatic patients and those with nasal symptoms. Data were presented as median (interquartile range). A receiver operating curve was used to predict the diagnostic utility of turbinate tissue sIgE in determining allergic rhinitis. RESULTS: A total of 160 patients (41.89 ± 14.65 years, 36.9% females) were included. The median tissue sIgE concentration among the asymptomatic nonatopic group of patients was 0.09 (0.08-0.10) kUA/L and tissue sIgE > 0.10 kUA/L was determined as a positive threshold. Inferior turbinate tissue sIgE was shown to be a predictive test for allergic rhinitis (area under curve: 0.87, 95% confidence interval: 0.84-0.90) with 90% sensitivity and 89% negative predictive value. CONCLUSION: Inferior turbinate tissue biopsy sIgE is a sensitive tool to predict allergic rhinitis. The threshold value of 0.1 kUA/L corresponded well with the asymptomatic nonatopic group of patients. This method detects sIgE in the nasal mucosa and may be a useful test for allergic rhinitis in future research.

Optimizing Protein Harvest From Nasal Brushings for Determining Local Allergy Responses.

Background Rhinitis is a highly prevalent yet often misdiagnosed condition. Patients who have local allergic rhinitis are regularly mislabeled as having a nonallergic etiology. Thus, a highly accurate, reproducible, and noninvasive assessment, which can be performed quickly and with minimal discomfort to the patient, is required. Objective The aim of this research was to identify the efficiency of various nasal brushes as tools for harvest and collection of epithelial proteins and its suitability for identification of rhinitis. Methods Nasal epithelial mucosa samples were taken from patients undergoing turbinate surgery using a cytology brush, a dental brush, and a nasal curette in random order. After washing in phosphate-buffered saline, the suspended cells were sonicated. Total protein content was assessed for all samples by bicinchoninic acid assay measured using a Nanodrop machine. Identification of nasal-specific immunoglobulin E (spIgE) was then assessed using immunoassay and compared to the patient's allergic status from epicutaneous and serum testing. The lower threshold limit for the spIgE in nasal brushings was determined using the results of serum spIgE tests as the reference. The diagnostic accuracy of this new established cutoff value was determined. Results The cytology brush was found to be the optimal tool for maximal nasal mucosa protein collection followed by dental brush and nasal curette (0.75 ± 0.45 mg/mL vs 0.43 ± 0.24 mg/mL vs 0.071 ± 0.55 mg/mL, respectively; P < .01). The optimal cutoff value of nasal spIgE from the cytology nasal brushings was 0.14 kUA/L to predict allergic status from serum testing. This gave a sensitivity of 75%, specificity of 86%, positive predictive value of 74%, likelihood ration positive of 5.40, and diagnostic odds ratio of 18.62. Conclusion The cytology brush is the optimal tool for protein collection. This is an easy and direct method to sample the nasal mucosa for assessment of nasal allergy or future biomarkers.