Defining phenotypes in rhinitis: a step toward personalized medicine

Diagnosis and management of nonallergic rhinitis with eosinophilia syndrome using cystatin SN together with symptoms

Background

The diagnosis and treatment of nonallergic rhinitis with eosinophilia syndrome (NARES) remain controversial. The aim of this study was to evaluate whether Cystatin SN together with symptoms can be used to diagnose NARES and to measure the efficiency of medical treatment.

Methods

Seventy-five patients with chronic rhinitis (CR) and 18 control subjects were enrolled. Their clinical characteristics were reviewed and laboratory parameters were evaluated. The concentration of Cystatin SN in nasal secretions was determined using the enzyme-linked immunosorbent assay. The histological assessment of Cystatin SN in the nasal mucosa was conducted by hematoxylin and eosin staining. The logistic regression and receiver operating characteristic curves were used to assess the predictive value of parameters for NARES.

Results

Nasal obstruction, sneezing, loss of smell, and total visual analogue scale (VAS) score were significantly different among the patients with CR. In particular, olfaction score was higher in patients with NARES than in those without NARES (AR, LAR, or IR). Similarly, the Cystatin SN level was significantly different between the control subjects and patients with CR. After treatment for 2 weeks, the Cystatin SN level and VAS score were significantly decreased in the NARES group. The accuracy of Cystatin SN together with local sIgE and loss of smell to diagnose NARES was up to 0.987 (sensitivity, 100%; specificity, 93.1%).

Conclusions

Cystatin SN with local sIgE and loss of smell may serve as one of the reliable and alternative biomarkers for the diagnosis of NARES and be used to evaluate disease severity and NARES treatment efficacy.

Phenotypes of allergic diseases in children and their application in clinical situations

Allergic diseases, including allergic rhinitis, asthma, and atopic dermatitis, are common heterogeneous diseases that encompass diverse phenotypes and different pathogeneses. Phenotype studies of allergic diseases can facilitate the identification of risk factors and their underlying pathophysiology, resulting in the application of more effective treatment, selection of better treatment responses, and prediction of prognosis for each phenotype. In the early phase of phenotype studies in allergic diseases, artificial classifications were usually performed based on clinical features, such as triggering factors or the presence of atopy, which can result in the biased classification of phenotypes and limit the characterization of heterogeneous allergic diseases. Subsequent phenotype studies have suggested more diverse phenotypes for each allergic disease using relatively unbiased statistical methods, such as cluster analysis or latent class analysis. The classifications of phenotypes in allergic diseases may overlap or be unstable over time due to their complex interactions with genetic and encountered environmental factors during the illness, which may affect the disease course and pathophysiology. In this review, diverse phenotype classifications of allergic diseases, including atopic dermatitis, asthma, and wheezing in children, allergic rhinitis, and atopy, are described. The review also discusses the applications of the results obtained from phenotype studies performed in other countries to Korean children. Consideration of changes in the characteristics of each phenotype over time in an individual’s lifespan is needed in future studies.

Endotypes of chronic rhinitis: A cluster analysis study

BACKGROUND

Chronic rhinitis (CR) is currently regarded as a syndrome, which presents as several endotypes. The aim of this study was to identify the CR endotype clusters and investigate the inflammatory patterns associated with the different endotypes.

METHODS

A total of 259 CR patients and 20 control subjects were enrolled in this prospective study. Twelve clinical variables were analyzed using cluster analysis and five inflammatory variables were measured to investigate the inflammatory patterns associated with the different clusters.

RESULTS

Six endotype clusters of CR were defined in the Chinese CR patients. Patients in cluster 1 (38.6%) were diagnosed as allergic rhinitis (AR) without asthma, and in cluster 2 (13.5%) as AR with asthma, with all demonstrating positive results for local eosinophils and high levels of local and serum IgE. Similarly, patients in cluster 3 (18.6%) were diagnosed as nonallergic rhinitis with eosinophilia syndrome (NARES) without asthma and in cluster 5 (5.0%) as NARES with asthma, with all demonstrating positive results for local eosinophils, and negative results for both local and serum IgE. Patients in cluster 4 (4.6%) were diagnosed as local allergic rhinitis and showed positive results for local eosinophils and local IgE, but negative results for serum IgE, whereas patients in cluster 6 (19.7%) were diagnosed as idiopathic rhinitis because of high symptoms scores, but negative findings for local eosinophils, local IgE, and serum IgE.

CONCLUSIONS

Chinese CR patients may be clustered into six endotypes with different inflammatory patterns, which may help in delivering individualized treatment.

Phenotypes and Emerging Endotypes of Chronic Rhinosinusitis

Chronic rhinosinusitis can be differentiated into several phenotypes based on clinical criteria; however, these phenotypes do not teach us much about the underlying inflammatory mechanisms. Thus, the use of nasal endoscopy and CT scanning, and eventually taking a swab or a biopsy, may not be sufficient to fully appreciate the individual patient's pathology. Endotyping of chronic rhinosinusitis on the basis of pathomechanisms, functionally and pathologically different from others by the involvement of specific molecules or cells, may in contrast provide us with information on the risk of disease progression or recurrence and on the best available treatment, and also helps us identifying innovative therapeutic targets for treatment. Endotyping may best be structured around T helper cells and their downstream events, such as tissue eosinophilia or neutrophilia; this approach involves the cytokines and chemokines related to specific T helper cell populations, and related markers such as IgE. Endotyping is of specific interest at the time of the arrival of new biologicals, confronting us with the challenge of the selection of eligible patients for treatment and predicting their therapeutic response; defining suitable biomarkers is therefore an urgent task. Failure to appreciate the underlying mechanisms and endotypes of chronic rhinosinusitis may limit progress in the management of the disease at present.

Allergic and Nonallergic Asthma Have Distinct Phenotypic and Genotypic Features

BACKGROUND

Identification of asthma phenotypes enables a better understanding and management of this heterogeneous disease. Studies have reported associations between human leukocyte antigens (HLA) and asthma in different populations, but the results have been inconclusive and they have rarely considered the distinct disease phenotypes. Our objective was to characterize allergic and nonallergic asthma phenotypes and evaluate possible associations with the HLA system.

METHODS

A total of 109 patients with asthma were prospectively followed during 2 years. They were divided into 2 groups, i.e., allergic and nonallergic asthma, according to their clinical history and skin prick test and serum-specific immunoglobulin E (IgE) results. The control group comprised 297 deceased donors of solid organs. Patients' features and HLA class I and II genotypes were assessed and compared.

RESULTS

This study showed different features between asthma phenotypes. Nonallergic patients were older at the onset of asthma symptoms and had a higher rate of intolerance to nonsteroidal anti-inflammatory drugs. Allergic patients had higher total serum IgE levels, reported atopic dermatitis and rhinoconjunctivitis more frequently, and, unexpectedly, had a greater disease severity. New associations between the HLA genotypes and allergic and nonallergic asthma were identified. The HLA-B*42, HLA-C*17, HLA-DPA1*03, and HLA-DPB1*105 genotypes were associated with allergic asthma and the HLA-B*48 genotype with the nonallergic phenotype. The presence of the haplotype HLA-DPA1*03 DQA*05 was associated with allergic asthma, and the presence of HLA-DPA1*03 and the absence of HLA-DQA*05 with nonallergic asthma.

CONCLUSIONS

Allergic and nonallergic asthma have distinct phenotypic and genotypic features. New associations between asthma phenotypes and HLA class I and II were identified.

Natural Course of Allergic and Nonallergic Rhinitis After 2 Years in Korean Children

Objectives.

Allergic and nonallergic rhinitis are very common disease for children, however, little is known about their natural courses in the general population. The purpose is to evaluate the natural course of allergic and nonallergic rhinitis in children.

Methods.

We analyzed data from Snoring Child Cohort of 178 children (107 boys and 71 girls). All children entered the study at the age of 7 years (range, 6.5 to 7.4 years). Questionnaires regarding chronic rhinitis, a skin prick test (SPT) for 5 inhalent allergens, and specific IgE for 2 dust mites were administered. Children were classified into 4 groups: allergic rhinitis (rhinitis, positive SPT), nonallergic rhinitis (rhinitis, negative SPT), sensitization only (no rhinitis, positive SPT), and control (no rhinitis, negative SPT). We repeated follow them annually, and analyzed the data of first and third year for this study.

Results.

Finally, the data of 122 children were analyzed. Among 18 children with allergic rhinitis at 7 years, 13 (72%) became sensitization only after 2 years and 5 (28%) were remained having allergic rhinitis. Five out of 19 children (26%) with nonallergic rhinitis developed into allergic rhinitis and 7 (37%) into control at 9 years. Twenty-four out of 28 children (86%) with sensitization only at 7 years remained the same at 9 years. Among 57 control children at 7 years, 2 (4%) developed into allergic rhinitis, 7 (12%) with nonallergic rhinitis, and 16 (28%) with sensitization only at 9 years.

Conclusion.

The status of chronic rhinitis and allergen sensitization is ever-changing in children.