Rhinovirus C and respiratory exacerbations in children with cystic fibrosis.

To investigate a possible role for human rhinovirus C in respiratory exacerbations of children with cystic fibrosis, we conducted microbiologic testing on respiratory specimens from 103 such patients in São Paulo, Brazil, during 2006-2007. A significant association was found between the presence of human rhinovirus C and respiratory exacerbations.

ABPA diagnosis in cystic fibrosis patients: the clinical utility of IgE specific to recombinant Aspergillus fumigatus allergens.

OBJECTIVE: Allergic bronchopulmonary aspergillosis (ABPA) is a complicating factor of cystic fibrosis which can result in a devastating combination as lung disease progresses. The overlap between the signs and symptoms of the two conditions makes diagnosis problematic, even if standardized criteria are used. The objective of this study was to identify, in a group of cystic fibrosis patients, cases of ABPA by assaying IgE specific to recombinant Aspergillus fumigatus antigens and to compare the method with the Cystic Fibrosis Foundation diagnostic criteria. METHODS: Fifty-four patients, aged 2 to 20 years, presenting characteristics that could occur with ABPA in isolation, were systematically assessed based on the following: clinical data, a chest CT scan, immediate hypersensitivity skin test for A. fumigatus, total serum IgE assay, RAST for A. fumigatus and serum IgE specific for the recombinant allergens Asp f1, f2, f3, f4 and f6. RESULTS: Thirty-nine patients were eligible for the study. Thirty-two of these were investigated. Sensitization to A. fumigatus was observed in 34%. Both the Cystic Fibrosis Foundation criteria and the recombinant antigen specific IgE assay defined three patients as suffering from ABPA; however, only two of these patients were diagnosed by both methods. CONCLUSIONS: The detection of A. fumigatus recombinant antigen specific IgE was a useful tool for the early detection of sensitization and diagnosis of ABPA. Nevertheless, diagnostic confirmation cannot be divorced from clinical findings, and before this method can be used for ABPA diagnosis, for detecting relapses and for defining cure criteria, longitudinal studies with larger numbers of patients are required.

Ozone is associated with an increased risk of respiratory exacerbations in patients with cystic fibrosis.

BACKGROUND: Tropospheric oxidant pollutants may injure the respiratory tract. Cystic fibrosis (CF) respiratory disease involves significant inflammation and excessive oxidative stress, and exposure to air pollutants can magnify the lung damage. The objective of this study was to investigate the association between the short-term variation in the concentration of air pollutants in metropolitan São Paulo, Brazil, and the occurrence of respiratory exacerbations in children and adolescents with CF. METHODS: A longitudinal panel of repeated measurements was obtained from 103 patients attending the outpatient center of our institution from September 6, 2006 through September 4, 2007. Daily concentrations of inhaled particulate matter, sulfur dioxide, nitrogen dioxide, ozone (O3), carbon monoxide, and meteorologic variables, such as the minimum temperature and relative humidity, were evaluated. The generalized estimation equation model for binomial distribution was used to assess the impact of these measurements on the occurrence of acute respiratory exacerbations. RESULTS: In total, 103 patients with CF (median age, 8.9 years) made 408 visits, with a mean ± SD of 4 ± 1.74 visits per patient (range, 2-9). A respiratory disease exacerbation was diagnosed on 142 visits (38.4%). An interquartile range increase in the O3 concentration (45.62 µg/m3) had a positive, delayed (2 days after exposure) effect on the risk of a respiratory exacerbation (relative risk = 1.86; 95% CI, 1.14-3.02). CONCLUSIONS: This study demonstrates that exposure to short-term air pollution in a large urban center increases the risk of a pulmonary exacerbation in patients with CF.

Diagnóstico de ABPA em pacientes portadores de fibrose cística: utilidade clínica da pesquisa de IgE específica contra alérgenos recombinantes do Aspergillus fumigatus / ABPA diagnosis in cystic fibrosis patients: the clinical utility of IgE specific to recombinant Aspergillus fumigatus allergens

OBJETIVO: A aspergilose broncopulmonar alérgica (ABPA) é um fator complicador da fibrose cística que pode determinar uma combinação devastadora na evolução da doença pulmonar. A sobreposição de sinais e sintomas das duas enfermidades dificulta o diagnóstico, mesmo aplicando critérios padronizados. O objetivo deste trabalho foi identificar, em grupo de portadores de fibrose cística, os casos de ABPA através da detecção de IgE específica contra os alérgenos recombinantes do Aspergillus fumigatus e confrontar esse método com os critérios preconizados pela Cystic Fibrosis Foundation. MÉTODOS: Cinqüenta e quatro pacientes de 2 a 20 anos, com características que poderiam estar isoladamente presentes na ABPA, foram avaliados sistematicamente, incluindo: dados clínicos, tomografia computadorizada de tórax, teste cutâneo de hipersensibilidade imediata para A. fumigatus; dosagem de IgE sérica total, RAST para A. fumigatus, e IgE sérica específica para alérgenos recombinantes r Asp f1, f2, f3, f4 e f6. RESULTADOS: Foram elegíveis para o estudo 39 pacientes. Destes, 32 foram investigados. Houve sensibilização ao A. fumigatus em 34 por cento. Ambos os métodos, o critério da Cystic Fibrosis Foundation e a pesquisa de IgE específica contra antígenos recombinantes, determinaram três casos de ABPA; entretanto, o diagnóstico foi concordante em apenas dois pacientes. CONCLUSÃO: A detecção de IgE específica contra antígenos recombinantes do A. fumigatus foi ferramenta útil para detecção precoce da sensibilização e diagnóstico de ABPA. No entanto, a confirmação diagnóstica não pôde ser desvinculada da condição clínica, e sua utilização para diagnóstico, detecção de recidivas e critério de cura ainda requer estudos longitudinais, envolvendo maior número de pacientes.