Prevalence of food allergen and aeroallergen sensitization among children in Sichuan province.

Food allergen and aeroallergen sensitization are common allergic diseases worldwide, with widely varying estimates of prevalence in children. Our study investigated the characteristics of ingestion and inhalation allergy among children from Sichuan province in Southwest China, so as to get public awareness of these disorders.A total of 1722 children between 0 and 14 years' old were enrolled in this study. They were outpatients in the West China Second University Hospital during June 2019 to September 2019. Serum specific IgE specific to 10 types of food allergen and 10 types of aeroallergen were estimated. Nutrition indicators were tested by electrochemical luminescence.59.70% children were allergic to at least 1 allergen, comprising 24.90% to aeroallergen and 38.81% to food allergen, respectively, whereas 36.28% children were allergic to both aeroallergen and food allergen. Milk was the most common food allergen, and egg came in second place. With regard to aeroallergen, house dust mite held the maximum proportion (65.02%), whereas dust mite followed behind. Inhalation allergy was more commonly seen in boys than girls. Bronchitis was the most common symptom of both allergies. In addition, the highest incidence age for children to be sensitive to food allergen and aeroallergen were 0∼2 years' old and 3∼5 years' old, respectively. It is worth mentioning that there was no significant difference in nutritional status between children with or without allergic diseases.Our findings reveal that milk, egg, house dust mite, and dust mite are the most common allergens among children in Sichuan province. Boys are more susceptible to aeroallergen than girls. Furthermore, the prevalence of ingestion and inhalation allergy varies from different age groups, and has no correlation with nutritional status. In brief, the analysis of the pattern of food allergen and aeroallergen sensitization is invaluable to effective diagnosis and treatment of allergic diseases.

Nasal allergen challenge and environmental exposure chamber challenge: A randomized trial comparing clinical and biological responses to cat allergen.

BACKGROUND: The direct-instillation nasal allergen challenge (NAC) and the environmental exposure chamber (EEC) are 2 methods of conducting controlled allergen provocations. The clinical and biological comparability of these methods has not been thoroughly investigated. OBJECTIVE: We sought to compare clinical and immunologic responses to cat allergen in NAC versus EEC. METHODS: Twenty-four participants were randomized to receive either NAC followed by a 2-day challenge in an EEC or a 2-day challenge in an EEC followed by NAC. Challenges were separated by 28-day washout periods. We measured total nasal symptom scores, peak nasal inspiratory flow, nasal (0-8 hours) and serum cytokines, serum antibodies, peripheral blood antigen-specific T lymphocytes, and gene expression in nasal scrapings. The primary outcome was the total nasal symptom score area under the curve for the first 3 hours after allergen exposure in NAC or after initiation of exposure in EEC. RESULTS: Both challenges increased IL-5 and IL-13 in nasal fluids and serum and resulted in altered nasal cell expression of gene modules related to mucosal biology and transcriptional regulation. Changes in gene modules, more so than cytokine measurements, showed significant associations with total nasal symptom score and peak nasal inspiratory flow. Overall, EEC exposure generated larger responses and more early terminations compared with NAC. Although the 2 challenges did not correlate in symptom magnitude or temporality, striking correlations were observed in cytokine levels. CONCLUSIONS: Although clinical outcomes of NAC and EEC were temporally different and nonequivalent in magnitude, immunologic responses were similar. Selection of a particular allergen challenge method should depend on considerations of study objectives and cost.

Inhaled IL-2 induces systemic immunomodulation in patients with renal cell carcinoma and lung metastasis.

The peripheral blood lymphocytes of eight patients with metastatic renal cell carcinoma, and of eight healthy volunteers were analyzed by four-color flow cytometry to characterize the immunophenotypic alterations manifested, determine the prevalence of lymphocyte apoptosis, and detect evidence of the systemic effect of inhaled IL-2. The T, B and NK lymphocytes of untreated patients were found to have undergone profound changes characterized by an increase in susceptibility to both spontaneous and mitogen-induced ex vivo apoptosis, a modified distribution of the main lymphocyte populations in the peripheral blood, and alterations in activation status. An increase in the proportion of regulatory T cells was also seen in these patients. Treatment with inhaled IL-2, however, normalized the rate of apoptosis in all the lymphocyte subpopulations studied, as well as their distribution and activation status. These findings demonstrate that inhaled IL-2 has systemic immunomodulatory effects.

Influence of sensitization to inhalative allergens on adenotonsillar disease.

OBJECTIVE: We sought to determine the influence of IgE-mediated sensitization on adenotonsillar disease in children. We compared follow-up after tonsillectomy/adenoidectomy of atopic and nonatopic children.Study design and setting A prospective study of 293 children consecutively undergoing tonsillectomy/adenoidectomy was conducted at a university hospital center. Preoperative and postoperative (1-year follow-up) allergy-related symptom scores were obtained by parents. Intraoperative total serum IgE, the screening test sx1 (Pharmacia), and, if positive, serum specific IgE to inhalative allergens were carried out. RESULTS: Sixty-seven children (22.9%) showed positive RAST results to inhalative allergens (class 1 to 6). In both sensitized and nonsensitized groups, the general health was improved in more than 89% at 1 year postoperatively. No significant difference of postoperative nasal symptoms between the atopic and nonatopic groups was found. CONCLUSION: Both atopic and nonatopic children with adenotonsillar disease improve health after adenoidectomy or adenotonsillectomy. In our opinion, routine allergy tests before adenotonsillectomy or adenoidectomy are not justified. Only if allergy is suspected due to clinical findings or family history should an allergy test be carried out.

Positive nasal challenge responses to Blomia tropicalis.

BACKGROUND: Blomia tropicalis, a dust mite commonly found in subtropical and tropical environments, is the fourth most common mite in the United States. Thirty-eight percent of 167 consecutive subjects evaluated for allergic respiratory symptoms in the Tampa Bay area had positive skin test responses to B. tropicalis. METHODS: Nasal challenges were performed in 19 subjects with allergic rhinitis; 12 had positive skin test responses to B. tropicalis (group I), and seven had negative skin test responses to B. tropicalis but positive skin test responses to Dermatophagoides pteronyssinus and D. farinae (group II). Subjects were challenged with a normal saline control solution and increasing concentrations of a 1 mg/ml in-house extract of B. tropicalis (1:125,000 vol/vol, 1:25,000 vol/vol, 1:5000 vol/vol, 1:1000 vol/vol, and 1:200 vol/vol). Inspiratory nasal airway resistance (was measured every 5 minutes for 15 minutes by posterior rhinomanometry at 50 Pa after each nasal challenge. RESULTS: Nasal challenge response was considered positive and stopped when the mean inspiratory nasal airway resistance was greater than twice the mean inspiratory nasal airway resistance after the normal saline challenge. Ten of 12 (83%) subjects in group I and none of seven (0%) subjects in group II had positive nasal challenge responses to B. tropicalis (p = 0.0024). CONCLUSION: B. tropicalis is allergenic and should be considered as a cause of allergic rhinitis when evaluating a patient who lives in an area where it is endemic.

Increased levels of exhaled nitric oxide during nasal and oral breathing in subjects with seasonal rhinitis.

BACKGROUND: Allergic rhinitis is associated with nasal mucosal inflammation. Exhaled nitric oxide may be a useful marker of inflammation and has recently been shown to be increased in patients with asthma. OBJECTIVE: The purpose of this study was to determine whether exhaled levels of nitric oxide are increased with nasal breathing in patients with seasonal allergic rhinitis compared with nonatopic individuals and whether there is an increase with oral breathing consistent with lower respiratory inflammation in the absence of clinical asthma. METHODS: Nitric oxide levels in exhaled air were measured by chemiluminescence in 18 nonatopic volunteers and 32 patients with seasonal rhinitis. Measurements were made with both nasal and oral exhalation and orally after 10 seconds and 60 seconds of breath-holding. The detection limit was 1 part per billion (ppb). RESULTS: In control subjects nasal levels of nitric oxide in exhaled air (mean +/- SD, 24.7 +/- 9.2 ppb) were higher than those after oral exhalation (11.1 +/- 2.5 ppb, p less than 0.0001). Breath-holding significantly increased levels of nitric oxide in exhaled air in a time-dependent manner. Levels of exhaled nitric oxide were significantly higher for all measurements in patients with seasonal rhinitis, with levels without breath-holding of 35.4 +/- 11.3 ppb (p less than 0.001) in nasally exhaled air and 16.3 +/- 5.9 ppb (p less than 0.001) in orally exhaled air. Nasal levels were significantly higher than oral levels in subjects with rhinitis (p less than 0.0001). CONCLUSIONS: The results indicate that exhaled nitric oxide may be a useful marker for nasal inflammation in patients with seasonal rhinitis and suggest that generalized airway inflammation may be present, even without clinical asthma, in such patients.

Reflujo y asma en el lactante / Reflux and asthma in the lactant

Hay muchas teorías que atribuyen a la presencia de reflujo gastroesofágico (RGE) ser causa desencadenante o agravante (o ambas) del estado de hiperreactividad bronquial (HRB). La relación entre el aumento de los síntomas broncoobstructivos del lactante, en particular durante la noche, y el RGE o la microaspiración alimentaria (MAA) o ambos aún es tema de debate. Por otra parte, el RGE y la MAA se presentan en el lactante con una frecuencia tal que muchos autores los postulan como fisiológicos. Desde 1984 estamos aplicando un test citológico sensible y específico para el diagnóstico de la MAA independiente de la presencia de RGE o no en el lactante. Con el propósito de evaluar la asociación del RGE, la MAA y los niveles de anticuerpos contra la leche de vaca se estudiaron 35 niños (de 2 a 22 meses) con obstrucción bronquial recurrente; todos completaron el estudio (RGE por diagnóstico radiológico contrastado; MAA por citología de aspirado faríngeo, IgE total e IgE Rast para leche por RIA) fueron divididos en dos grupos: 22 niños (m:15; f:7) con valores elevados de IgE + 2 DE y 13 niños (m:5; f:8) como grupo control con valores normales de IgE+2 DE. Se concluye que la presencia de RGE (81,81 por ciento y 84,61 por ciento), MAA (72,72 por ciento y 76,92 por ciento) y asociación entre RGE y MAA (63,63 por ciento y 61,55 por ciento) es muy elevada en ambos grupos; esto podría explicar la frecuente presencia en ellos de anticuerpos circulantes anti leche de vaca grado 1 (45,45 por ciento y 46,15 por ciento) determinados por IgE Rast-específica. Sólo en el primer grupo se encontraron anticuerpos circulantes anti leche de vaca grado 2 (13,63 por ciento) en coincidencia con valores elevados de IgE. Estos hallazgos sugieren que el pulmón tendría una importante participación en la hipersensibilidad a la leche de vaca