Pesticide exposure and health conditions of terrestrial pesticide applicators in Córdoba Province, Argentina / Exposición a plaguicidas y condiciones de salud de agroaplicadores terrestres de la Provincia de Córdoba, Argentina / Exposição aos agrotóxicos e condições de saúde dos aplicadores de pesticidas da Província de Córdoba, Argentina

Agricultural workers represent a population that is highly vulnerable to the toxic effects of pesticide exposure. This cross sectional study aimed to describe the health conditions of terrestrial pesticide applicators in Córdoba Province, Argentina, their work practices and socio-demographic characteristics, by means of a standardized self-administered questionnaire (n = 880). A descriptive analysis reported a high prevalence of occasional or frequent symptoms: 47.4% had symptoms of irritation, 35.5% fatigue, 40.4% headache and 27.6% nervousness or depression. Using logistic regression models, risk and protective factors were found for symptoms of irritation, medical consultation and hospitalization. Among the occupational exposure variables, marital status, length of time in the job, low level of protection with regard to the use of personal protective equipment, combined use of different pesticides and the application of the insecticide endosulfan, were associated with a higher frequency of reported symptoms and higher consultation rates and hospitalization.

Los trabajadores agrícolas son una población altamente vulnerable a los efectos tóxicos de la exposición a plaguicidas. Con el objetivo de describir las condiciones de salud de agroaplicadores terrestres de plaguicidas de la Provincia de Córdoba, Argentina, sus prácticas laborales y características sociodemográficas, se realizó un estudio transversal, mediante cuestionario (n = 880). Un análisis descriptivo reportó alta prevalencia de sintomatología ocasional o frecuente: 47,4% síntomas irritativos, 35,5% cansancio, 40,4% cefalea y 27,6% ansiedad o depresión. Mediante modelos logísticos se detectaron factores protectores y de riesgo que explican la presencia de síntomas irritativos, la consulta médica y la hospitalización. El estado civil, la antigüedad en la tarea, el nivel de protección considerando uso de equipo de protección personal, la exposición múltiple a plaguicidas y la aplicación del insecticida endosulfán, se asociaron a mayor frecuencia de reporte de síntomas, consultas médicas y hospitalizaciones por causas relacionadas con la exposición a plaguicidas.

Os trabalhadores agrícolas são uma população altamente vulnerável aos efeitos tóxicos da exposição a pesticidas. Este estudo transversal teve o objetivo de descrever as condições de saúde de aplicadores terrestres de pesticidas da Província de Córdoba, Argentina, suas práticas de trabalho e características sociodemográficas, por meio de um questionário padronizado autoadministrado (n = 880). A análise descritiva relatou alta prevalência de sintomas ocasionais ou frequentes: 47,4% sintomas irritativos, 35,5% fadiga, 40,4% dor de cabeça e 27,6% ansiedade ou depressão. Mediante modelos logísticos foram detectados os fatores protetores e do risco que explicam a presença de sintomas irritativos, consulta médica e hospitalização. O estado civil, anos de trabalho, o nível de proteção considerando o uso de equipamentos de proteção individual, a exposição a vários pesticidas e aplicação do inseticida endosulfan, foram associados com maior frequência de sintomas, consultas médicas e hospitalização por causas relacionadas à exposição ao agrotóxico.

Avaliação da hiperresponsividade brônquica à solução salina hipertônica em crianças e adolescentes / Bronchial hyperresponsiveness to hypertonic saline challenge in children and adolescents

OBJETIVO: Avaliar a hiperresponsividade brônquica à solução salina hipertônica a 4,5 por cento como método alternativo a outros agentes broncoconstritores e sua relação com a sensibilização alérgica do paciente. MÉTODOS: Estudo transversal, experimental, com 85 indivíduos assim distribuídos: 45 no grupo de asmáticos e 17 no grupo controle não asmáticos e não alérgicos, que completaram o teste. Para nebulizar a solução salina hipertônica foi utilizado um nebulizador ultra-sônico de grande volume, sucessivamente durante 0,5, 1, 2, 4 e 8 minutos até haver queda > 15 por cento em relação ao volume expiratório forçado no primeiro segundo basal. A dosagem de imunoglobulina E específica ao Dermatophagoides pteronyssinus por ImmunoCap foi considerada positiva quando > 0,35 kU/L. RESULTADOS: No grupo de asmáticos, 36 apresentaram queda média do volume expiratório forçado no primeiro segundo de 27,4 por cento após nebulização de solução salina hipertônica. Nenhum do grupo controle (imunoglobulina E < 0,35 kU/L) apresentou resposta à solução salina hipertônica e a queda média do volume expiratório forçado no primeiro segundo foi de 9 por cento. Nove asmáticos tiveram provocação brônquica negativa. A freqüência de provocação brônquica positiva foi maior nos indivíduos com imunoglobulina E específica elevada, o que indica uma relação entre hiperresponsividade brônquica e o nível sérico de imunoglobulina E específica. A sensibilidade do teste foi de 80 por cento e a especificidade de 92 por cento. CONCLUSÃO: A inalação de solução salina hipertônica é um método de provocação útil para avaliar hiperresponsividade brônquica em crianças e adolescentes, com adequadas sensibilidade e especificidade, além do baixo custo e necessidade de poucos equipamentos.

OBJECTIVE: To assess airway hyperresponsiveness to 4.5 percent hypertonic saline solution in comparison to that obtained through challenge with other bronchoconstriction agents and in relation to patient allergic sensitization. METHODS: A cross-sectional, experimental study was conducted, initially involving 85 subjects. After exclusions, the final sample consisted of 62 patients, divided into two groups: a study group of those with asthma (n = 45) and a control group of those with no asthma or allergies (n = 17). Hypertonic saline was nebulized using an ultrasonic nebulizer and administered successively for 0.5, 1, 2, 4 and 8 minutes until a drop in forced expiratory volume in one second of = 15 percent was achieved in relation to the baseline value. The level of specific immunoglobulin E to Dermatophagoides pteronyssinus level was determined by ImmunoCAP assay and was considered positive when > 0.35 kU/L. RESULTS: In the 36 asthma group subjects presenting a response, the mean drop in forced expiratory volume in one second after hypertonic saline nebulization was 27.4 percent. None of control group subjects (immunoglobulin E < 0.35 kU/L) presented a positive response to hypertonic saline. The mean forced expiratory volume in one second for control group subjects was 9 percent. The results of a bronchial provocation test were negative in 9 of the asthma group subjects. The frequency of bronchial provocation test positivity was higher in the subjects presenting elevated levels of specific immunoglobulin E, indicating that there is a relationship between bronchial hyperresponsiveness and the level of specific immunoglobulin E. The sensitivity and specificity of the test were 80 percent and 92 percent, respectively. CONCLUSION: Bronchial provocation with hypertonic saline presents satisfactory sensitivity and specificity. Therefore, in addition to being a low cost procedure that requires very little equipment, it is a useful means of assessing ...

Bronchial hyperresponsiveness and analysis of induced sputum cells in Crohn's disease

With the aim of investigating the presence of latent inflammatory process in the lungs of patients with Crohn's disease, 15 patients with Crohn's disease were evaluated by spirometry, the methacholine challenge test, induced sputum, and skin tests for inhaled antigens. Serum IgE, erythrocyte sedimentation rate and hematocrit were also determined. The patients were compared with 20 healthy controls by the Mann-Whitney and Fisher exact tests. Their respiratory physical examination was normal. None had a personal or family history of clinical atopy. None had a previous history of pulmonary disease, smoking or toxic bronchopulmonary exposure. None had sinusitis, migraine, diabetes mellitus, or cardiac failure. Four (26.6 percent) of the patients with Crohn's disease had a positive methacholine challenge test whereas none of the 20 controls had a positive methacholine test (P = 0.026, Fisher exact test). Patients with Crohn's disease had a higher level of lymphocytes in induced sputum than controls (mean 14.59 percent, range 3.2-50 vs 5.46 percent, 0-26.92 percent, respectively; P = 0.011, Mann-Whitney test). Patients with Crohn's disease and a positive methacholine challenge test had an even higher percentage of lymphocytes in induced sputum compared with patients with Crohn's disease and a negative methacholine test (mean 24.88 percent, range 12.87-50 vs 10.48 percent, 3.2-21.69 percent; P = 0.047, Mann-Whitney test). The simultaneous findings of bronchopulmonary lymphocytosis and bronchial hyperresponsiveness in patients with Crohn's disease were not reported up to now. These results suggest that patients with Crohn's disease present a subclinical inflammatory process despite the absence of pulmonary symptoms.

Pharaoh Ant (Monomorium pharaonis): Newly Identified Important Inhalant Allergens in Bronchial Asthma

The nonstinging house ant, Monomorium pharaonis (pharaoh ant), was recently identified as a cause of respiratory allergy. This study was performed to evaluate the extent of sensitization to pharaoh ant, and its clinical significance in asthmatic patients. We carried out skin prick tests in 318 patients with asthma. Specific IgE (sIgE) to pharaoh ant was measured by ELISA, and cross-reactivity was evaluated by ELISA inhibition tests. Bronchial provocation testing was performed using pharaoh ant extracts. Fifty-eight (18.2%) of 318 patients showed positive skin responses to pharaoh ant, and 25 (7.9%) had an isolated response to pharaoh ant. Positive skin responses to pharaoh ant were significantly higher among patients with non-atopic asthma than among those with atopic asthma (26.0% vs. 14.9%, p<0.05). There was significant correlation between sIgE level and skin responses to pharaoh ant (rho=0.552, p<0.001). The ELISA inhibition tests indicated that pharaoh ant allergens had various pattern of cross-reactivity to house dust mites and cockroaches. Bronchial provocation tests to pharaoh ant were conducted for 9 patients, and eight showed typical asthmatic reactions. In conclusion, pharaoh ant is an important source of aeroallergens, and it should be included in the skin test battery for screening the causative allergens in patients with asthma.

Nasal Eosinophilic Inflammation Contributes to Bronchial Hyperresponsiveness in Patients with Allergic Rhinitis

There are increasing evidences that allergic rhinitis (AR) may influence the clinical course of asthma. We conducted methacholine challenge test and nasal eosinophils on nasal smear to patients with allergic rhinitis in order to investigate the mechanism of connecting upper and lower airway inflammation in 35 patients with AR during exacerbation. The methacholine concentration causing a 20% fall in FEV1 (PC20) was used as thresholds of bronchial hyperresponsiveness (BHR). Thresholds of 25 mg/dL or less were assumed to indicate BHR. All patients had normal pulmonary function. Significant differences in BHR were detected in the comparison of patients with cough or postnasal drip and without cough or postnasal drip. There were significant differences of PC20 between patients with cough or postnasal drip and those without cough or postnasal drip (3.41 +/-3.59 mg/mL vs 10.2 +/-1.2 mg/mL, p=0.001). The levels of total IgE were higher in patients with seasonal AR than in patients with perennial AR with exacerbation (472.5 +/-132.5 IU/L vs. 389.0 +/-70.9 IU/L, p<0.05). Nasal eosinophils were closely related to log PC20 (r=-0.65, p<0.01). These findings demonstrated that nasal eosinophilic inflammation might contribute to BHR in patients with AR.

High Body Mass Index is Associated with Wheezing Among Older Adults Living in High-Altitude Area in Korea

Although the association between obesity and asthma has been well documented, the nature of this association has yet to be clarified. The aim of this study was to examine the association of body mass index (BMI), lipid profiles, and atopy, wheezing, and lung function in older adults living in a rural area in Korea. BMI (kg/m2), lipid profiles, skin prick test, spirometry, and questionnaire including airway symptoms were obtained in a cross-sectional survey in 707 (259 males and 448 females) older adults (aged 50 to 93; mean, 65.7 yr) living in a high-altitude rural area in Korea. The prevalence of self-reported wheezing was 17.1% (121/707). The prevalence of atopy was 13.8%. The mean of BMI was 23.3+/-0.13 (14.6-32.8). The BMI was higher in females than in males (23.8+/-0.16 vs 22.4+/-0.17; p or = 25 than in group with BMI<25 [57/201 (28.3%) vs 64/505 (12.6%), p<0.01]. The BMI was higher in group with wheezing than in group without wheezing (24.3+/-0.34 vs 23.1+/-0.13, p<0.01). No association between BMI and atopy was found. These findings suggest that BMI associated with wheezing in older adults.

Correlación entre atopia e hiperreactividad bronquial inespecífica en niños asmáticos / Correlation between atopy and nonespecific bronquial hyperresponsiveness in asthmatic children

Hiperreactividad bronquial (HRB) y atopia se asocian a menudo en el asma bronquial de la infancia y es cada vez mayor el número de estudios que así lo sugieren. Con la finalidad de cuantificar esa asociación, se estudiaron 35 niños asmáticos atópicos, entre 7 y 16 años, divididos en tres grupos de acuerdo con la severidad clínica-leve, moderada y severa. Material y métodos: Se determinó el grado de reactividad bronquial por inhalación de metacolina (PC20 VEF1 en mg/ml), pruebas cutáneas con aeroalergenos por método escarificación e IgE sérica total (en Ul/ml) por radioinmunoanálisis (RIA). Como parámetro principal de atopia se establecieron dos puntajes de pruebas cutáneas (PPC): PPc1: número de antígenos positivos (pápula igual o mayor de 3mm) y PPC2: suma de los diámetros (mm) de las pápulas generadas por los antígenos positivos. Resultados: Se observaron diferencias significativas para cada una de las variables estudiadas según el grado de severidad clínica del asma (para PC20 VEF1 p < 0,001; PPC1 p < 0,001; PPC2 p < 0,001 e IgE sérica total p < 0,001). Existió una correlación significativa entre PPC1 y PPC2 y el grado de reactividad bronquial medida por el log (PC20 VEF1) (r=0,61, p < 0,001 y r=0,65, p < 0,001 respectivamente). Lo mismo surgió de correlacionar IgE sérica y log (PC20 VEF1) (r=0,78, p < 0,001). Conclusiones: Creemos que la sensibilización con aeroalergenos es un factor relevante en la génesis del asma de la infancia; este estudio mostró que los parámetros de atopia considerados se asociaron en forma cuantitativa con el grado de severidad clínica del asma y de reactividad bronquial a la metacolina

Emergence of T-lymphocytes, eosinophils and dendritic cells in the bronchi of actively sensitized guinea pigs after antigenic challenge

Bronchi from guinea pigs actively sensitized to ovalbumin and boosted two weeks later display increased numbers of CD4+ T-lymphocytes and eosinophils. We have further investigated immunopathological changes in sensitized guinea pigs 2 or 24 h after antigenic challenge with ovalbumin. Lungs were resected, frozen and cryostat sections stained with monoclonal antibodies that recognize relevant guinea pig epitopes. Cyanide-resistant peroxidase activity was used to stain eosinophils. No further increase in T-lymphocytes or eosinophils was observed 2 h after challenge. At 24 h, a marked increase in EPO+ eosinophils was found, and this was accompanied by severe mucosal damage characterized by epithelial shedding and ulceration. The numbers of T-lymphocytes remained stable but a novel population of cells with the appearance of dendritic cells was seen in the bronchial wall. They were negative for macrophage markers but were strongly Class II positive. These findings suggest that antigenic challenge results in further recruitment of eosinophils, their activation and release of toxic substances to the epithelium. Furthermore, other cell types, possibly dendritic cells, are attracted to the bronchi and could play a role in maintaining allergic inflammation via antigen presentation.

Reactividad bronquial inespecífica y eosinofilia hemática en niños con asma extrínseca e intrínseca / Nonspecific bronchial reactivite and hematic eosinophilia in the children with extrinsic and intrinsic asthma

El asma bronquial presenta grados variables de inflamación e hiperreactividad bronquial, dos fenómenos fisiopatogénicos que se expresan, para muchos autores, con sugestivo paralelismo. El eosinófilo parece desempeñar un papel central en la patogenia de la flogosis bronquial y todo indica que proviene de la circulación periférica, atraído por divesos estímulos quimiotácticos. Su recuento en sangre podría proveer un parámetro indirecto del grado de reactividad bronquial en pacientes asmáticos. Nosotros estudiamos la relación existente entre el número de eosinófilos en sangre periférica y el grado de reactividad bronquial inespecífica (RBI) a la metacolina, en un grupo de niños con asma extrínseca (AE)- o alérgica- y asma intrínseca (AI)- o no alérgico. Pacientes y métodos: se incluyen 39 niños -entre 6 y 14 años- con AE y un grupo de 20 niños con AI -entre 7 y 14 años- a quienes se les realizó recuento de eosinófilos en sangre periférica- expresado en número absoluto por mm3- y pruebas de broncoprovocación con metacolina- PC VEF- como parámetro de reactividad bronquial inespecífica. Las variables RBI y eosinofilia hemática fueron comparadas entre ambos grupos mediante el test U de Mann-Withney; en cada grupo se estudió la asociación entre ambas por análisis de regresión. Resultados: se observaron diferencias significativas para los valores de PC VEF, de metacolina entre ambos: AIX =6.66Ï1.77 y AEX=2.32Ï0,77 (p=0,004). No ocurrió lo mismo con el recuento de eosinófilos: Al X=570Ï95.3 y AEX=649.9Ï62.4 (p=NS). Existió una importante correlación entre ambos parámetros en los niños con AI (r=0.75,p<0.001) y fue algo menor en los que padecían AE (=0.43p<0.001). Conclusiones: estas observaciones permiten especular que en la infancia la atopía puede ser condicionante de una mayor reactividad bronquial. En el asma infantil la eosinofilia hemática parece ser un indicador indirecto del grado de reactividad bronquial a la metacolina, observación que en nuestro estudio se hace más evidente en intrínsecos que en extrínsecos