Effect of continuing the use of renin-angiotensin system inhibitors on mortality in patients hospitalized for coronavirus disease 2019: a systematic review, meta-analysis, and meta-regression analysis.

BACKGROUND: The effect of angiotensin-converting enzyme inhibitors (ACEIs)/angiotensin receptor blockers (ARBs) on mortality was preliminarily explored through the comparison of ACEIs/ARBs with non-ACEIs/ARBs in patients with coronavirus disease 2019 (COVID-19). Reaching a conclusion on whether previous ACEI/ARB treatment should be continued in view of the different ACE2 levels in the comparison groups was not unimpeachable. Therefore, this study aimed to further elucidate the effect of ACEI/ARB continuation on hospital mortality, intensive care unit (ICU) admission, and invasive mechanical ventilation (IMV) in the same patient population. METHODS: We searched PubMed, the Cochrane Library, Ovid, and Embase for relevant articles published between December 1, 2019 and April 30, 2022. Continuation of ACEI/ARB use after hospitalization due to COVID-19 was considered as an exposure and discontinuation of ACEI/ARB considered as a control. The primary outcome was hospital mortality, and the secondary outcomes included 30-day mortality, rate of ICU admission, IMV, and other clinical outcomes. RESULTS: Seven observational studies and four randomized controlled trials involving 2823 patients were included. The pooled hospital mortality in the continuation group (13.04%, 158/1212) was significantly lower than that (22.15%, 278/1255) in the discontinuation group (risk ratio [RR] = 0.45; 95% confidence interval [CI], 0.28-0.72; P = 0.001). Continuation of ACEI/ARB use was associated with lower rates of ICU admission (10.5% versus 16.2%, RR = 0.63; 95% CI 0.5-0.79; P < 0.0001) and IMV (8.2% versus 12.5%, RR = 0.62; 95% CI 0.46-0.83, P = 0.001). Nevertheless, the effect was mainly demonstrated in the observational study subgroup (P < 0.05). Continuing ACEI/ARB had no significant effect on 30-day mortality (P = 0.34), acute myocardial infarction (P = 0.08), heart failure (P = 0.82), and acute kidney injury after hospitalization (P = 0.98). CONCLUSION: Previous ACEI/ARB treatment could be continued since it was associated with lower hospital deaths, ICU admission, and IMV in patients with COVID-19, although the benefits of continuing use were mainly shown in observational studies. More evidence from multicenter RCTs are still needed to increase the robustness of the data. Trial registration PROSPERO (CRD42022341169). Registered 27 June 2022.

Blood Eosinophil Endotypes across Asthma and Chronic Obstructive Pulmonary Disease (COPD).

Background: Eosinophils were common inflammatory cells involved in the occurrence and development of various inflammatory diseases. Multiple recent studies have pointed to the increasingly important role of eosinophils in respiratory diseases. This article aims to compare the expression differences of blood eosinophil counts between asthma, chronic obstructive pulmonary disease (COPD), and asthma-COPD overlap (ACO). Methods: Patients with asthma, COPD, and ACO who were seen in the First Affiliated Hospital of Guangzhou Medical University from January 2012 to June 2019 were included. We collected information such as age, gender, diagnosis, the eosinophil counts from the medical records. Moreover, the levels of 10 cytokines in the plasma of each group were detected by using the Meso Scale Discovery method. Results: We included 9787 patients with asthma, 15806 patients with COPD, and 831 ACO patients. From our results, it can be first found that eosinophil levels were age-related in the three diseases (asthma and ACO: p < 0.001; COPD: P = 0.001); in asthma and COPD, the number of eosinophils in males was more significant than that in females (asthma: p < 0.001; COPD: p = 0.012). Second, asthma patients had higher blood eosinophil counts than those with COPD and ACO (p < 0.001). Moreover, we found out that eosinophil levels were highly expressed in the stable group of all three diseases. Finally, we found that most cytokines in ACO patients showed a downward trend when the level of eosinophils was low, whereas the results were reversed in asthma patients; 7 cytokines had similar trends in COPD and ACO patients. Conclusions: In conclusion, eosinophils have their own unique endotypes in asthma, COPD, and ACO patients, which were reflected in the fluctuation of their levels and changes in cytokine secretion.

Efficacy of air purifier therapy for patients with allergic asthma

Objectives: This study aimed to evaluate the efficacy of air purifier therapy for patients with allergic asthma. Methods: Thirty-eight subjects were categorized under two groups namely treatment group and control group. All subjects were under 18 years of age and they had been clinically diagnosed with allergic asthma. The treatment group used high efficiency particulate air (HEPA) purifiers for six consecutive months, and the control group did not use the air filters. Particulate matter (PM) data and dust samples (from bedding and a static point) were collected from the subjects’ bedrooms before they started using the air purifiers and each month thereafter. Simultaneously, the subjects were asked to complete a questionnaire for the Asthma Control Test (ACT) or Childhood Asthma Control Test (C-ACT). Fractional exhaled nitric oxide (FENO) tests were performed at the start and end of the study. The concentrations of Der p1 and Der f1 were measured in the dust samples. Results: (1) After utilizing the air purifier, the concentrations of house dust mite (HDM) allergens (Der p1+ Der f1) in the dust samples decreased. In addition, the PMindoor/outdoor values significantly decreased. (2) The ACT and C-ACT scores in the treatment group maintained a steady significant upward trend. (3) At the end of the study, the FENO levels in both groups were lower, although the differences were not significant. Conclusions: It is witnessed that HEPA air purifiers can decrease indoor HDM allergen and PM levels and improve the quality of life for allergic asthma patients (AU)

Serum levels of the IgA isotype switch factor TGF-ß1 are elevated in patients with COVID-19.

We previously observed enhanced immunoglobulin A (IgA) responses in severe COVID-19, which might confer damaging effects. Given the important role of IgA in immune and inflammatory responses, the aim of this study was to investigate the dynamic response of the IgA isotype switch factor TGF-ß1 in COVID-19 patients. We observed, in a total of 153 COVID-19 patients, that the serum levels of TGF-ß1 were increased significantly at the early and middle stages of COVID-19, and correlated with the levels of SARS-CoV-2-specific IgA, as well as with the APACHE II score in patients with severe disease. In view of the genetic association of the TGF-ß1 activator THBS3 with severe COVID-19 identified by the COVID-19 Host Genetics Initiative, this study suggests TGF-ß1 may play a key role in COVID-19.

Clinical application of fractional exhaled nitric oxide and nasal nitric oxide levels for the assess eosinophilic inflammation of allergic rhinitis among children.

BACKGROUND: Allergic rhinitis is one of the most common nasal inflammatory diseases among children. Assessment of clinical symptoms, skin prick test and serum immunoglobulin E (IgE) are common methods used to diagnose allergic rhinitis and assess inflammation degree in clinical settings. However, via blood tests assess eosinophils inflammation is invasive, and may cause fear in children. It makes have burden of the diagnosis of allergic rhinitis. Nasal nitric oxide (nNO) and fractional exhaled nitric oxide (FeNO) are noninvasive, inexpensive, and can provide immediate results. These methods may therefore be preferable to assess the inflammation of allergic rhinitis. METHODS: This study was a retrospective analysis. We recruited 61 children with allergic rhinitis from November 2019 to March 2020. The participants were assessed using the FeNO and nNO tests. We also administered questionnaires and carried out traditional allergen and blood tests. We analyzed the relationship between diagnosis results and FeNO and nNO levels before and after the treatment of allergic rhinitis, to investigate the clinical application of FeNO and nNO levels for assess eosinophilic inflammation of allergic rhinitis in children. RESULTS: We observed a significant association both FeNO, nNO level with eosinophils, total IgE. In different levels of eosinophils (EOS), the correlation of detection parameters had obvious change. FeNO and nNO levels were obvious higher compared to pre-treatment. CONCLUSIONS: Using NO concentration can indicates the extent of allergic inflammation and can measure allergy treatment effects combine other influence indexes. The combined use of FeNO and nNO levels may be a useful method for assess the degree of eosinophilic inflammation of allergic rhinitis in children.

Multiplexed analysis of circulating IgA antibodies for SARS-CoV-2 and common respiratory pathogens in COVID-19 patients.

Previous studies have revealed a diagnostic role of pathogen-specific IgA in respiratory infections. However, co-detection of serum specific IgA for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and common respiratory pathogens remains largely unexplored. This study utilizes a protein microarray technology for simultaneous and quantitative measurements of specific IgAs for eight different respiratory pathogens including adenovirus, respiratory syncytial virus, influenza virus type A, influenza virus type B, parainfluenza virus, mycoplasma pneumoniae, chlamydia pneumoniae, and SARS-CoV-2 in serum sample of patients with coronavirus disease 2019 (COVID-19). A total of 42 patients with COVID-19 were included and categorized into severe cases (20 cases) and nonsevere cases (22 cases). The results showed that co-detection rate of specific-IgA for SARS-CoV-2 with at least one pathogen were significantly higher in severe cases than that of nonsevere cases (72.2% vs. 46.2%, p = .014). Our study indicates that co-detection of IgA antibodies for respiratory pathogens might provide diagnostic value for the clinics and also be informative for risk stratification and disease management in patients with COVID-19.

Factors associated with exhaled nitric oxide in children with asthma and allergic rhinitis.

BACKGROUND: Factors attributable to the level of fraction of exhaled nitric oxide (FeNO) in different age groups of asthmatic children are still lack of report. OBJECTIVE: To evaluate factors associated with FeNO and the response of FeNO to inhaled steroid in different age groups of asthmatic children with allergic rhinitis. METHODS: Asthmatic children aged 5 to 12 years were recruited. FeNO, lung function and bronchial hyperresponsiveness (BHR) to methacholine, skin prick testing to a panel of aeroallergens, total immunoglobulin E (T-IgE) in serum and eosinophils in blood were tested. Correlations between FeNO and the measured parameters were assessed. FeNO was measured again after the treatment of combined inhaled corticosteroid and long-acting beta-agonist (ICS/LABA) for 4 weeks. Changes in FeNO between different age groups were compared. RESULTS: A total of 121 eligible subjects were enrolled in and completed this study. Asthmatic children aged 10 to 12 years old had significantly higher FeNO than those between 8 and 9 years and 5 to 7 years of children (both P < 0.01). Greater height/age (P < 0.01) and higher level of total allergen IgE (P < 0.01) are associated with a higher value of FeNO. After 4 weeks of treatment with ICS/LABA, asthma control test scores were significantly increased in all age groups (P < 0.01), while the level of FeNO significantly decreased in the elder age group only (P < 0.01). CONCLUSIONS: Height and T-IgE are well correlated with FeNO in asthmatic children aged 5 to 12 years. Measurement of FeNO is more suitable for evaluating the efficacy of ICS/LABA in elder asthmatic children.

Effects of Intranasal Cellulose Powder on Asthma Control in Children With Mild-to-Moderate Perennial Allergic Rhinitis: A Randomized, Placebo-Controlled Trial.

BACKGROUND: Perennial allergic rhinitis (PAR) often coexists in asthmatic patients. Intranasal cellulose powder (ICP) was reportedly effective in ameliorating PAR. OBJECTIVE: We investigated whether ICP is equally effective compared with intranasal corticosteroids in improving asthma control as well as nasal symptoms among children with PAR and allergic asthma (AA). METHODS: Between July 2015 and September 2016, we did a single-center, randomized, placebo-controlled trial. Asthmatic children aged 6 to 11 years with mild-to-moderate PAR were randomly assigned to formoterol/budesonide inhalation (4·5 µg/80 µg, twice daily) plus intranasal budesonide 64 µg twice daily (group A), ICP 250 µg thrice daily (group B), or intranasal placebo 250 µg thrice daily (group C) for 8 weeks. The primary outcome was change in asthma control test for children (C-ACT) score from baseline to week 8 posttreatment. Changes in spirometry, peak expiratory flow (PEF), fractional exhaled nitric oxide (FeNO), and visual analog scale (VAS) for nasal and ocular symptoms were detected as secondary outcomes. RESULTS: We included 121 patients (38 in group A, 41 in group B, and 42 in group C) in full-analysis set. C-ACT score was markedly higher at week 8 compared with baseline (mean difference: 5.11, 6.05, and 4.85 points in groups A, B, and C, respectively; P < .05). There were interactions between baseline and treatment in C-ACT scores ( P < .05). Group B demonstrated greater improvement in C-ACT score than group C among children with baseline C-ACT score of 6 to 18. 95% confidence intervals of group A at baseline overlapped with those of groups B and C. The treatment achieved reduced VAS symptoms in groups A and B but not in group C. Incidence of adverse events was comparable. No serious adverse event was reported. CONCLUSIONS: ICP could be recommended for children with PAR and AA who have poorer asthma control.

Profiling of polyunsaturated fatty acids in human serum using off-line and on-line solid phase extraction-nano-liquid chromatography-quadrupole-time-of-flight mass spectrometry.

Polyunsaturated fatty acids (PUFAs) play a pivotal role in the biological effects, and are the potential biomarkers for some diseases. However, the structural diversity and similarity, the low concentration, and the interference of high abundant endogenous components challenge the PUFAs profiling. Herein, a novel analytical approach, off-line and on-line solid phase extraction-nano-liquid chromatography-quadrupole-time-of-flight mass spectrometry (off-line and on-line SPE-nano-LC-Q-TOF-MS), was established to monitor the PUFAs. The combination of off-line and on-line SPE removed most of impurities, and the recoveries ranged from 80.1% to 93.0% and the matrix effects were from 85.1% to 92.8%. Using this method, 51 PUFAs could be separated well and quantified with the limits of quantification between 0.006 and 2.2 pg. Finally, this developed method was applied successfully to simultaneously qualify and quantify the potential biomarkers in the allergic patients. 21 PUFAs including LTB4, 5S-, 11S-, 15S-HETE and 15S-HEPE showed significant differences. Our study indicated that the established method has the potential to sensitively and accurately determine the PUFAs in biological samples.

Acid/Salt/pH Gradient Improved Resolution and Sensitivity in Proteomics Study Using 2D SCX-RP LC-MS.

The usage of strong cation exchange (SCX) chromatography in proteomics is limited by its poor resolution and nonspecific hydrophobic interactions with peptides, which lead to peptide overlap across fractions and change of peptide retention, respectively. The application of high concentration of salt (up to 1000 mM) in SCX also restricted its use in online 2D SCX-RP LC. In the present research, we first exploited the chromatographic ability of online 2D SCX-RP LC by combination of acid, salt, and pH gradient, three relatively independent modes of eluting peptides from SCX column. 50% ACN was added to elution buffer for eliminating hydrophobic interactions between SCX matrix and peptides, and the concentration of volatile salt was reduced to 50 mM. Acid/salt/pH gradient showed superior resolution and sensitivity as well as uniform distribution across fractions, consequently leading to significant improvements in peptide and protein identification. 112 191 unique peptides and 7373 proteins were identified by acid/salt/pH fractionation, while 69 870 unique peptides and 4536 proteins were identified by salt elution, that is, 62.5 and 60.6% more proteins and unique peptides, respectively, identified by the former. Fraction overlap was also significantly minimized by acid/salt/pH approach. Furthermore, acid/salt/pH elution showed more identification for acidic peptides and hydrophilic peptides.

Characterization of a new subtype of allergen in dermatophagoides farinae-Der f 28.

BACKGROUND: House dust mites (HDMs) are the major sources of indoor allergens which induce asthma, dermatitis, rhinitis, and some other allergic diseases. Close to 30 sub-allergens have been identified. METHODS: Through analyzing the full genome sequence of dust mite, a new allergen whose primary structure belongs to the heat shock protein family was identified. The sequence of this allergen was determined by cDNA cloning. The allergenicity was assayed by skin prick test, Western-blot and enzyme-linked immunosorbent assay (ELISA). RESULTS: r-Der f 28 bound to serum IgE from mite allergic patients. Positive responses to r-Der f 28 were shown in 11.5% by skin prick testing from 26 DM-allergic patients. Airway hyperresponsiveness, serum specific IgE and IL-4 were significantly increased in allergic asthma mouse model sensitized to r-Der f 28. CONCLUSIONS: Der f 28 is a new subtype of allergen in dermatophagoides farinae.

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

BACKGROUND: Although 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. METHODS: A 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. RESULTS: Analysis 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. CONCLUSIONS: The 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.

Allergy-related evidences in relation to serum IgE: data from the China state key laboratory of respiratory disease, 2008-2013.

OBJECTIVE: To investigate the serum total IgE (tIgE) and specific IgE (sIgE) to common allergens among allergic patients in Guangzhou, China. METHODS: 7 085 patients were examined for tIgE and sIgE to 15 allergens, based on the protocols of reversed enzyme allergosorbent test and the sandwich enzyme-linked immunosorbent assay. RESULTS: 3 758 (53.04%) patients tested positive for tIgE, and 4 640 (65.49%) for sIgE. Der pteronyssinus, Der farinae, eggs, and cow's milk were the most common allergens leading to higher positive rates of sIgE responses. Several peaks of sensitization were: Der pteronyssinus, Der farinae, and Blomia tropicalis at age 10-12; cow's milk at age below 3; eggs at age 4-6. The mean level and positive rate of tIgE tended to increase in subjects sensitized to more allergens. Sensitization to Der pteronyssinus (OR, 1.6; P<0.05), Der farinae (OR, 1.5; P<0.05), Blomia tropicalis (OR, 1.4; P<0.05), Blattella germanica (OR, 1.5; P<0.05), cow's milk (OR, 1.3; P<0.05), and soy beans (OR, 2.0; P<0.05) were independently correlated with allergy-related conditions in preliminary diagnosis. CONCLUSION: The major allergens in Guangzhou include Der pteronyssinus, Der farinae, cow's milk, and eggs. Sensitization to these allergens appears to be predictors of allergy-related disorder.

Prevalence of allergen sensitization among patients with allergic diseases in Guangzhou, Southern China: a four-year observational study.

BACKGROUND: The distribution of allergens may vary with different geographic areas, suggesting the importance of local epidemiological data to support evidence-based prevention and management of allergic diseases. We investigated the distribution of common allergens in allergic patients in Guangzhou, southern China. METHODS: 7,047 patients with allergic symptoms were examined for serum sIgE to 15 common allergens in this region, based on the protocol of reversed enzyme allergosorbent test. RESULTS: 4,869 (69.09%) of the subjects tested positive for sIgE to at least one of the 15 common allergens. There was no statistical difference in the overall rate of positive sIgE detection between males (3128/4523, 69.16%) and females (1741/2524, 68.98%). Der pteronyssinus and Der farinae were the most common aeroallergens, while eggs and cow's milk the most common food allergens, responsible for higher positive rates of sIgE responses. A good correlation in positive sIgE response was found between Der pteronyssinus and Der farinae. By age-group analysis, we noted several peaks of sensitization to certain allergens: Der pteronyssinus, Der farinae, and Blomiatropicalis at age between 9 and 12; Blattellagermanica and mosquito at age between 15 and 18, cow's milk before age 3; eggs and flour at age between 3 and 6; crabs and shrimps at age between 12 and 15. Along with older age, there was an ascending tendency in the overall positive rate of sIgE response to house dust mites among subjects who tested positive for sIgE to eggs or cow's milk. CONCLUSIONS: Der pteronyssinus, Der farinae, cow's milk, and eggs are major allergens in Guangzhou. Sensitization to eggs and cow's milk is more common at younger age, and then gives place to the increasing prevalence of sensitization to Der pteronyssinus and Der farinae at older age. Such a sequence of events may be a result of allergy march. Knowledge on the prevalence of allergen sensitization in different age groups would help early diagnosis and intervention of allergic diseases in this large geographical region.

Reference values of induced sputum cytology in healthy children in guangzhou, southern china.

OBJECTIVE: To establish normal reference values of induced sputum cytology in healthy children in southern China. METHODS: During a period from January 2010 to December 2011, a total of 580 healthy children (5-16 years of age) were approached. A total of 266 children (137 boys and 129 girls) participated in the study. Sputum induction was carried out by using 5% hypertonic saline. Cell types in the sputum were examined by using routine methods. RESULTS: Sputum induction was completed in 175 of the 266 subjects (65.79%), but 16 sputum samples were disqualified. The overall success rate was 59.77% (159/266). Macrophages and neutrophils were the predominant cell types: macrophages: median, 76.14%; interquartile range (IQR), 32.68%; and 2.5% to 97.5% percentile, 1.00% to 94.50%; neutrophils: median, 20.67%; IQR, 33.0%; and 2.5% to 97.5% percentile, 4.00% to 92.75%; eosinophils: median, 0.39%; IQR, 1.93%; and 2.5% to 97.5% percentile, 0.00% to 6.50%; and lymphocytes: median, 1.22%; IQR, 2.04%; and 2.5% to 97.5% percentile, 0.00% to 5.00%. The cell types did not differ among different age, gender, and passive smoking groups. Adverse events occurred in 4.4% (7/159) of the participants who completed the procedures but required no specific treatment to dissipate. Peak expiratory flow did not differ between those who completed the procedures compared with those who did not, suggesting that the procedure is safe and feasible in children. CONCLUSIONS: The current study represents the first attempt to develop normal reference values of induced sputum cytology in Chinese children, and could be used as a control for future studies.

Add-on montelukast vs double-dose budesonide in nonasthmatic eosinophilic bronchitis: a pilot study.

BACKGROUND: Budesonide at 800 µg/d is generally suggested for treatment of nonasthmatic eosinophilic bronchitis (NAEB). In asthma, adjunctive therapy with montelukast has been shown to confer addictive anti-inflammatory effects to inhaled corticosteroid (ICS). However, whether such effects could be extrapolated to NAEB is not known. OBJECTIVES: To study the efficacy and tolerability of add-on therapy with montelukast as compared to double-dose ICS in suppressing airway eosinophilia and decreasing cough severity in NAEB. METHODS: In a randomized controlled trial, 26 nonsmoking, steroid-naïve NAEB patients presenting with chronic cough were treated with 800 µg/d budesonide or 400 µg/d budesonide plus montelukast 10 mg/d for 4 weeks. Cough visual analogue scale (CVAS) and eosinophil differential ratio in induced sputum (Eos) were monitored at baseline, Week 1, 2 and 4. Adverse events during treatment were recorded. RESULTS: The two groups were comparable in age, gender distribution, cough duration, FEV(1)% predicted, FEV(1)/FEV ratio, baseline CVAS and geometric mean of Eos. Both regimens significantly reduced Eos and CVAS throughout the treatment course, with abrogation of sputum eosinophilia at end of therapy. There was no significant difference between the two groups in reduction of Eos and CVAS at all time points. Both regimens were well tolerated. CONCLUSIONS: This preliminary study demonstrated that add-on montelukast might be an effective and well tolerated alternative to the generally suggested dose of ICS in treating steroid-naive NAEB, with suppression of eosinophilic inflammation, reduction of cough severity and sparing of ICS doses. (NCT01121016).

Prevalence of sensitivity to cockroach allergens and IgE cross-reactivity between cockroach and house dust mite allergens in Chinese patients with allergic rhinitis and asthma.

BACKGROUND: Cockroaches are an important indoor allergen source causing allergic rhinitis and asthma. The aim of this study was to investigate the cockroach prevalence in mainland of China and the cross-reactivity of IgE between cockroach and house dust mite allergen in Chinese patients. METHODS: The cockroach sensitization pattern was based on a skin prick test (SPT) obtained from a national multicenter prevalence study, in which 6304 patients from 25 allergy centers across China participated. Factors, including different regions of China, age, gender and the correlations between the American and German cockroaches and house dust mite Der p were investigated. Eighteen out of 1236 clinical sera from south China were selected to perform the cross-inhibition assay between house dust mites and cockroaches. RESULTS: Totally 25.7% of patients were SPT positive to the American cockroach (Periplaneta Americana, Per a) and 18.7% SPT positive to the German cockroach (Blattella germanica, Bla g). The prevalence of positive cockroach SPT was higher in southern than in northern China, higher in adults than in children, and higher in males than in females. Patients had relatively low levels of cockroach SPT reactions, mainly class 1 or 2. Of the SPT positive cockroach patients, 88% were also SPT positive to house dust mite (Dermatophagoides pteronyssinus, Der p). An IgE cross-inhibition study confirmed that Der p sensitization could cause false positive SPT reactions against cockroach. CONCLUSIONS: A relatively high prevalence of cockroach sensitivity was found in mainland of China. However, a cross-inhibition study showed that only a small number of patients appear to have Bla g and/or Per a as primary sensitizing source. The importance of cockroaches as a risk factor for sensitization and triggers of allergic symptoms in mainland of China needs to be further investigated.

[A survey on the relationship between atopy and bronchial asthma among adolescents in the city of Guangzhou, China].

OBJECTIVE: To access the relationship between atopy and bronchial asthma in adolescents. METHODS: A cross-sectional study was conducted. Cluster randomized subgroups of schoolchildren who had participated in ISAAC phase III survey in Guangzhou were enrolled from april to May, 2002. Skin prick test with 5 groups totally for 9 common aeroallergens (dermatophagoides pteronyssinus, Dermatophagoides farinae, cat, Alternaria tenuis, mixed tree pollen, mixed grass pollen, American cockroach, German cockroach and mixed moulds) was performed. Asthma was defined as wheezing or whistling in the chest in the lifetime or in the last 12 months, or diagnosed asthma. Allergy disease was defined as any of asthma, rhinitis and eczema. A wheal size with the diameter of 3 mm or more after subtraction of the negative control was considered as positive and subjects with one or more positive reactions were considered as atopy. The degree of atopy and the sensitivity of the allergen were graded by atopic index (AI) and skin index (SI), respectively. RESULTS: 1543 subjects were selected randomly for the skin prick test, and the response rate was 77.0% (1187/1543). 51.6% (613/1187) were males and 48.4% (574/1187) were females. The median age was 14 years old (range from 12 - 17 years old). The prevalence of asthma was 9.4% (111/1187), among whom 81.1% (90/111) also had rhinitis and 24.3% (27/111) had eczema. Asthma was more prevalent in 686 patients with rhinitis [13.1% (90/686)] or 200 patients with eczema [13.5% (27/200)] than those without rhinitis [4.2% (21/501), OR: 3.444, 95% CI: 2.110 - 5.622, P < 0.01] or eczema [8.5% (84/987), OR: 1.676, 95% CI: 1.055 - 2.663, P < 0.05]. The prevalence of atopy was 46.3% (549/1187) and the positive rates of house dust mite (Der p and Der f) were the highest [41.8% (496/1187) and 42.7% (507/1187), respectively]. Atopy was more common in asthmatic patients [71.2% (79/111)] than in those without any allergic diseases [26.4% (112/425), OR: 6.812, 95% CI: 4.276 - 10.853, P < 0.01]. Asthma was more prevalent in patients with atopy (14.4%) than those without atopy (5.5%, OR: 3.183, 95% CI: 2.075 - 4.883, P < 0.01). The relative risk of having asthma was increased with the higher AI degree. Univariate Logistic regression analysis showed that the risk factors for asthma were Der p (SI >/= 2), Der f (SI = 3 - 4), American cockroach, German cockroach, cat, Alternaria tenuis, mixed grass pollen. Multivariate Logistic regression analysis showed that Der p (SI = 3 - 4), and Alternaria tenuis were independent risk factors for asthma. CONCLUSION: Most asthmatic adolescents were allergic to house dust mite in the city of Guangzhou. The risk of asthma was positively correlated with the degree of atopy, as well as the sensitivity to Der p.