Nili Wei

Co-Sensitization to Silkworm Moth (Bombyx mori) and 9 Inhalant Allergens among Allergic Patients in Guangzhou, Southern China

Objectives This study aimed to investigate the profile of sensitization to silkworm moth (Bombyx mori) and other 9 common inhalant allergens among patients with allergic diseases in southern China. Methods A total of 175 patients were tested for serum sIgE against silkworm moth in addition to combinations of other allergens: Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis, Blattella germanica, Periplaneta americana, cat dander, dog dander, Aspergillus fumigatus and Artemisia vulgaris by using the ImmunoCAP system. Correlation between sensitization to silkworm moth and to the other allergens was analyzed. Results Of the 175 serum samples tested, 86 (49.14%) were positive for silkworm moth sIgE. With high concordance rates, these silkworm moth sensitized patients were concomitantly sensitized to Dermatophagoides pteronyssinus (94.34%), Dermatophagoides farinae (86.57%), Blomia tropicalis (93.33%), Blattella germanica (96.08%), and Periplaneta americana (79.41%). Moreover, there was a correlation in serum sIgE level between silkworm moth and Dermatophagoides pteronyssinus (r = 0.518), Dermatophagoides farinae (r = 0.702), Blomia tropicalis (r = 0.701), Blattella germanica (r = 0.878), and Periplaneta americana (r = 0.531) among patients co-sensitized to silkworm moth and each of these five allergens. Conclusion In southern Chinese patients with allergic diseases, we showed a high prevalence of sensitization to silkworm moth, and a co-sensitization between silkworm moth and other five common inhalant allergens. Further serum inhibition studies are warranted to verify whether cross-reactivity exists among these allergens.

Food allergy and related risk factors in 2540 preschool children: an epidemiological survey in Guangdong Province, southern China

BackgroundAlthough the number of studies on allergic diseases in the general population of southern China is increasing, only a few have addressed food allergy (FA) in children in this region. The present study aimed to investigate the prevalence, clinical manifestations, spectrum of allergens, and related risk factors of FA in preschool children in Guangdong Province, southern China.MethodsA random cluster-sampling method was used to select 24 kindergartens from 12 cities in Guangdong Province. The parents or guardians of the children were requested to complete a questionnaire on general information and data regarding FA diagnosis and symptoms in the children and their first-degree relatives. Thereafter, the Chi-square test, multivariate regression analysis, and Spearman’s rank-order correlation coefficient analysis were performed to identify statistically significant differences.ResultsAnalysis of 2540 valid questionnaires revealed an FA prevalence rate of 4%. Adverse food reactions were due to the consumption of shrimp (4.4%), crab (3.2%), mango (2.3%), cow’s milk and dairy products (1.9%), and eggs (1.4%). Logistic regression analysis indicated that a history of FA and a history of allergic rhinitis in the first-degree relatives were the major factors leading to FA in children.ConclusionsThe incidence of FA in children in Guangdong Province is higher than that commonly believed. An individual’s genetic background is an important risk factor for FA. Hence, mitigation of the impact of lifestyle and environmental factors should be carefully considered to reduce the incidence of childhood FA.

Major grass pollen allergens and components detected in a southern Chinese cohort of patients with allergic rhinitis and/or asthma.

There is so far a paucity of data about allergen component-resolved diagnosis, and the prevalence of grass pollen allergen components in China, in contrast to those from western countries. Even in this country, allergies to grass pollen allergen components in the vast south are inadequately described. This study aimed to determine the major sensitizing grass pollens in Guangzhou, the largest city in Guangdong province of southern China. Included in this study were 258 patients having allergic rhinitis with or without asthma and 88 healthy controls. ImmunoCap100 was used to examine the serum samples for sIgE to Bermuda, Timothy, and Humulus scandens. Subjects who tested positive were further examined for sIgE to Bermuda antigen Cyn d 1, Timothy antigens Phl p 1/4/5/6/7/11/12, and CCD. The relationship of grass pollen allergy to specific antigen sensitization was assessed. As a result, 22.5% of patients with allergic rhinitis and/or asthma were positive for Bermuda-sIgE, 13.6% for Timothy-sIgE, and 7.0% for Humulus scandens-sIgE. These patients were more likely to be sensitized compared with controls (P<0.001). Of the Bermuda-sIgE positive patients, 53.4% were Cyn d 1 positive and 60.3% were Timothy-sIgE positive. Of the Timothy positive patients, 100% were positive for Phl p 4, 17.1% were positive for Phl p 1 and 8.6% tested positive for Phl p 5/6/7/11/12. Patients with high Bermuda-sIgE levels were more likely to be positive for other grasses. In 41.4% of Bermuda grass positive patients, CCD-sIgE was also positive. Sensitization to Phl p 4 was significantly correlated with CCD (rs=0.928).In summary, we found that these southern Chinese patients with allergic rhinitis and/or asthma tested positive for Bermuda, Timothy, and Humulus scandens IgE. A high Bermuda-sIgE level may predict sensitization to other grasses. Correlations between sensitization to CCD and grass pollen allergens suggested a likelihood of cross-reactivity. Further in vitro inhibition assays are required to confirm this relationship.

A Component-resolved Diagnostic Approach for a Study on Grass Pollen Allergens in Chinese Southerners with Allergic Rhinitis and/or Asthma

Sensitization to grass pollen imposes a global risk for allergic airway diseases. Although prevention relies on local investigation of the pollen allergens, data on this topic are limited in southern China. Any available data were obtained by self-report questionnaires, skin prick tests, and total or specific IgE tests using crude extracts. For many reasons, these methods are unreliable. Serum sIgE reactivity to Bermuda grass, Timothy grass, and Humulus scandens allergens in a cohort of patients from Greater Guangzhou (southern Chinas largest city and its outskirts) with allergic rhinitis and/or asthma were examined using a fully-automated immunoassay analyzer as a component-resolved diagnostics (CRD) tool. For the first time, a considerably high prevalence of Bermuda grass sIgE positivity was demonstrated in Chinese southerners with allergic rhinitis and/or asthma. In these patients, a subtle prevalence of sensitization to Timothy grass and Humulus scandens was also noted, which may arise from cross-reactivity, as the latter two are not common in the region. This was also supported by the detection of allergen components. Fully-automated immunoassay analyzers may offer satisfactory consistency between regions, laboratories, and institutions and over time. The automaticity of the instrument may enable a standardized detection that would not have been readily revealed before the advent of CRD. This is a study that uses a CRD approach to investigate sensitization to grass pollen allergens in southern China. It adds to current evidence in the literature. Future studies are needed to validate these findings. However, although CRD is a useful tool, the findings made with the fully-automated immunoassay analyzer should not substitute for other laboratory investigations, clinical evaluations, and physician expertise.

Comparative Analysis of Serum Allergen sIgE Detected by Western Blotting and Fluorescent Enzyme Immunoassay

BACKGROUND Various new methods to diagnose allergens have gradually developed in recent years. The present study aimed to evaluate the diagnostic performance and clinical utility of Allergy-Q detection system (Proteometech Inc., Korea) on serum allergen-specific IgE (sIgE). METHODS Immunoblotting (Allergy-Q system) and fluorescent enzyme immunoassay (ImmunoCAP system, Phadia Inc., Sweden) were used to detect serum total IgE and allergen sIgE of 244 cases of allergic diseases, followed by comparative analysis of the results. The study focused on analyzing 15 kinds of common allergens. RESULTS Comparison of the two methods showed that the diagnostic performance of qualitative results of AllergyQ system for the majority of allergens was satisfactory, with Dermatophagoides farinae having the highest agreement (96.4%) and sensitivity (97.8%) and Dermatophagoides pteronyssinus having the highest specificity (100%), positive predictive value (100%), and Youdens index (J = 0.951). Scatter plots and Spearmans correlation analysis showed correlations between the quantitative results of the two methods, with the highest correlation for Dermatophagoides pteronyssinus (r = 0.875, p < 0.001). CONCLUSIONS For most common allergens, the Allergy-Q system is an effective method for diagnosis. It is safe, convenient, economical, accurate, and efficient in screening multi-allergens. Moreover, it is good for semi-quantitative detection of allergens in the basic hospitals that are unable to carry out the ImmunoCAP detection, and also for patients with fewer samples. However, its clinical application needs to be validated using a number of samples from a variety of countries and regions.

Diagnostic value of KL-6 in idiopathic interstitial pneumonia

Background Idiopathic interstitial pneumonia (IIP) can induce type II alveolar epithelial cell proliferation and pulmonary basement membrane damage and subsequent release of Krebs von den Lungen-6 antigen (KL-6) to the bloodstream. This study investigated the diagnostic and prognostic value of serum KL-6 levels for IIP. Methods One hundred five patients with lung disease were divided into IIP (n=75) and non-IIP groups (n=30) according to pathological and computed tomography findings. Serum KL-6 levels were evaluated in blood samples from all subjects. Nineteen IIP group patients were also subjected to a longitudinal study of disease progression and serum KL-6 levels over time. Results Serum KL-6 levels were significantly higher in the IIP group vs. the non-IIP group [1,096.0 (565.0-1,544.0) vs. 226.0 (173.5-346.5) U/mL; P<0.01]. Within the IIP group, serum KL-6 levels differed significantly between patients with and without concomitant disease or pulmonary infection (Z=-2.475, P=0.013). In a receiver operating characteristic (ROC) curve analysis, the area below the curve for serum KL-6 was 0.911 [95% confidence interval (CI): 0.847-0.975, P<0.001], indicating a good diagnostic performance for IIP, with a cut-off level of 485 U/mL, sensitivity of 85.33%, specificity of 90.00%, positive predictive value (PPV) of 95.52%, negative predictive value (NPV) of 71.05%, and Kappa value of 0.70. Accordingly, the serum KL-6 and clinical diagnostic results were consistent. Moreover, in the longitudinal study, the serum KL-6 levels differed significantly from before to after treatment in patients with exacerbated or improved disease (P=0.004 and P=0.043, respectively), whereas no obvious changes were observed in patients with stable disease (P=0.692). Conclusions The serum KL-6 level is a valuable and significant diagnostic marker of IIP and a useful predictor of clinical prognosis.

A cross-sectional observational study on allergen-specific IgE positivity in a southeast coastal versus a southwest inland region of China

Few studies addressed trans-regional differences in allergen sensitization between areas within a similar latitudinal range but with distinct geomorphological features. We investigated specific IgE (sIgE) positivity to common allergens in populations from two southern China provinces. Using a uniformed protocol, serum samples were collected from 2778 subjects with suspected atopy in coastal Guangdong and inland Yunnan. The overall prevalence of sIgE positivity were 57.8% (95% CI: 56.0%, 59.6%) from Guangdong vs 60.9% (95% CI: 59.1%, 62.7%) from Yunnan. House dust mite (d1) was the most common allergen in both regions. Among d1-sensitized subjects, only 35.7% (208/583) in Guangdong and 22.9% (147/642) in Yunnan tested positive for d1 alone. Among those poly-sensitized d1-positive subjects, cockroach was the most common co-sensitizing aeroallergen. 41.9% of the d1-sensitized Guangdong subjects showed high-class sIgE reactivity (≥class 4), in contrast to a very low percentage of such reactivity in Yunnan. However, 36.3% of d1-sensitized subjects in Yunnan were concomitantly positive for tree pollen mix. Surprisingly, Yunnan subjects showed high prevalence of sIgE positivity for crabs and shrimps, either by overall or by age-group analysis, compared with their Guangdong counterparts (both P < 0.05). These findings may add to data about local allergies in China and worldwide.

Longitudinal profiles of serum specific IgE and IgG4 to Dermatophagoides pteronyssinus allergen and its major components during allergen immunotherapy in a cohort of southern Chinese children

Longitudinal data on serum specific sIgE and sIgG4 to allergen component of Dermatophagoides pteronyssinus (Der p) during allergen immunotherapy (AIT) are limited in Chinese populations. We serially followed up serum sIgE and sIgG4 to Der p and its components (Der p 1 and 2) in 51 Der p-sensitized children receiving guideline-based medications alone and additional 36-month AIT. The the Der p 1 and Der p 2 sIgE levels were elevated at 6 months and progressively declined from 12 months; the sIgG4 levels for Der p, Der p 1 and Der p 2 were increasing during the first year and reached a plateau thereafter; the sIgE/sIgG4 ratios for Der p 1 and Der p 2 decreased continuously from 6 through 24 months of AIT. Subgroup analysis showed that younger children (≤8years) experienced a greater increase in sIgG4 levels for Der p, Der p 1 and Der p 2 during AIT compared with older children (9-16 years). In summary, sIgE and sIgG4 to Der p 1 and Der p 2 may be more useful than those to Der p in reflecting the change in immunological reactivity during AIT. Earlier delivery of AIT may yield greater increase in sIgG4 after 36-month treatment than given later in life.