Comparative microbiome analysis in cystic fibrosis and non-cystic fibrosis bronchiectasis.

BACKGROUND: Bronchiectasis is a condition characterized by abnormal and irreversible bronchial dilation resulting from lung tissue damage and can be categorized into two main groups: cystic fibrosis (CF) and non-CF bronchiectasis (NCFB). Both diseases are marked by recurrent infections, inflammatory exacerbations, and lung damage. Given that infections are the primary drivers of disease progression, characterization of the respiratory microbiome can shed light on compositional alterations and susceptibility to antimicrobial drugs in these cases compared to healthy individuals. METHODS: To assess the microbiota in the two studied diseases, 35 subjects were recruited, comprising 10 NCFB and 13 CF patients and 12 healthy individuals. Nasopharyngeal swabs and induced sputum were collected, and total DNA was extracted. The DNA was then sequenced by the shotgun method and evaluated using the SqueezeMeta pipeline and R. RESULTS: We observed reduced species diversity in both disease cohorts, along with distinct microbial compositions and profiles of antimicrobial resistance genes, compared to healthy individuals. The nasopharynx exhibited a consistent microbiota composition across all cohorts. Enrichment of members of the Burkholderiaceae family and an increased Firmicutes/Bacteroidetes ratio in the CF cohort emerged as key distinguishing factors compared to NCFB group. Staphylococcus aureus and Prevotella shahii also presented differential abundance in the CF and NCFB cohorts, respectively, in the lower respiratory tract. Considering antimicrobial resistance, a high number of genes related to antibiotic efflux were detected in both disease groups, which correlated with the patient's clinical data. CONCLUSIONS: Bronchiectasis is associated with reduced microbial diversity and a shift in microbial and resistome composition compared to healthy subjects. Despite some similarities, CF and NCFB present significant differences in microbiome composition and antimicrobial resistance profiles, suggesting the need for customized management strategies for each disease.

Repeatability of the 6-min walk test in non-cystic fibrosis bronchiectasis.

Non-cystic fibrosis bronchiectasis (NCFB) is a chronic lung disease characterized by progressive and irreversible changes of the bronchial tree. The evaluation of exercise capacity is essential to manage this disease. This study aims to determine the within-subject repeatability of two Six Minute Walk Test (6MWT) in adults with NCFB. NCFB. This cross-sectional observational study included 66 NCFB subjects above 18 years-old (mean of 55 ± 17 years old, 68% women). 73% of the participants presented moderate to severe clinical condition classified by Bronchiectasis Severity Index. It showed that these participants walked 16.6 m less (95%CI 3.8 to 29.4; p < 0.01) in the second 6MWT when compared to the first test, with a within-subject coefficient variation of 9.4% (95%CI 7.2-11.2%) and an intra-test reliability with a high intraclass correlation coefficient of 0.88 (95%CI 0.80-0.93). Bland-Altman plot showed an agreement regarding test repeatability, besides presented a large limit of agreement (- 85 to 116 m). Respiratory rate and systolic blood pressure were significantly higher before starting the second test. In conclusion, 6MWT seems to be reproducible in NCFB subjects and vital sign verification should be attentively checked to assess if the patient is fully recovered to perform a second test, as well as the disease severity score. Other studies on this matter should be conducted with a larger number of participants to confirm the findings of the present study.

Diet effects in the asthma treatment: A systematic review.

INTRODUCTION: Obesity in asthmatic patients has important relationships with asthma control, pulmonary function, and quality of life. The objective of this study was to conduct a systematic review of the literature on the effect of diet on asthma management in adults. METHODS: We searched PubMed, Embase, and Scopus (January 1948-October 2014) for randomized clinical trials that evaluated the effects of diet in adults with asthma. RESULTS: Of 12,215 studies identified, 21 were included. A reduction in weight of at least 7.5% from baseline as a result of caloric restriction can be beneficial for improving disease control, quality of life, and pulmonary function in obese patients with asthma. A dietary pattern rich in foods with potential antioxidant effect had an impact in improving asthma control, but with little clinical significance. Studies involving antioxidant supplementation showed improvements in asthma control with magnesium supplementation and less decline in lung function with vitamin C supplementation. Studies of fatty acid supplementation demonstrated effects on weight loss and improvement of asthma control and lung function. Studies of supplementation with propolis and caffeine reported significant increases in FEV1. Conversely, studies of high dietary salt intake reported greater declines in lung function. CONCLUSIONS: The evidence shows that, for obese adults with asthma, the best dietary intervention seems to be caloric restriction, regardless of specific dietary components.

Sinonasal characteristics and quality of life by SNOT-22 in adult patients with cystic fibrosis.

The prevalence of chronic sinus disease in cystic fibrosis (CF) has gradually increased. Sinonasal involvement may have influence on pulmonary exacerbations and can have a negative impact on the quality of life. To evaluate nasal characteristics and quality of life in adult patients with CF; to establish an association and determine the predictors in SNOT-22 questionnaire. Cross- sectional study with prospective data collection was performed to evaluate adult CF patients. Patients underwent clinical evaluation, lung function tests, nasal endoscopy, and paranasal sinuses CT scan. All the patients answered the SNOT-22 questionnaire. RESULTS: A total of 91 patients were allocated, of which, 45.1% were male. Patients were divided into three groups by SNOT-22. A high average age, late age of diagnosis, rhinitis symptoms, and clinical criteria for rhinosinusitis were observed more frequently in patients with high SNOT-22 scores (p < 0.05). Overall, 84.6% patients had abnormal CT findings, with aplasia/hypoplasia of the sphenoid sinus being the most common finding. In multiple regression model, age, female gender, and Pseudomonas aeruginosa in the sputum were associated with high SNOT-22 scores in the nasal domain. Hyposmia and lack of medial bulging of lateral nasal wall were variables associated with high SNOT-22 scores in the quality of life domain. In total score, there was a positive association with age and the presence of P. aeruginosa in sputum. Despite high prevalence of abnormal tomographic findings, patients reported mild intensity of sinonasal symptoms. Advanced age and the presence of P. aeruginosa were associated with higher SNOT-22 scores.

Repeatability of the 6-minute walk test in adolescents and adults with cystic fibrosis.

OBJECTIVE: To determine the repeatability of the 6-minute walk test (6MWT) in adolescents and adults with cystic fibrosis (CF). METHODS: This was a prospective cross-sectional study. We included consecutive patients ages>or=15 years attending an adult CF program. The patients underwent the 6MWT, pulmonary function tests, and clinical evaluation. The second 6MWT was performed following a rest period of 60 min. RESULTS: Thirty-one patients were included. The mean+/-SD age was 23.5+/-6.7 y, and the mean FEV1 was 61+/-28% of predicted. The mean+/-SD walked distance in the first 6MWT was 583.6+/-68.6 m and in the second 6MWT was 590.0+/-72.2 m. The mean difference between the first and second 6MWT was -6.5 m, with limits of agreement between -74.9 m and 61.9 m, and the coefficient of variation was 4.3%. The mean oxygen desaturation in the first 6MWT was 2.5+/-4.5%, and in the second test it was 1.8+/-4.0%. The mean difference between the first and second test was 0.6%, and the coefficient of variation was 104%. CONCLUSIONS: Although the 6MWT distance was reproducible, the wide limits of agreement exceeded the minimum important difference for this test. These findings indicate that, in the routine evaluation of CF patients, at least two 6MWTs are required on any testing occasion to obtain a reliable estimate of the 6MWT distance.

Doppler echocardiogram, oxygen saturation and submaximum capacity of exercise in patients with cystic fibrosis.

STUDY OBJECTIVES: To determine the relationship between pulmonary arterial systolic pressure (PASP) and submaximum capacity of exercise, using the six-minute walk test (6MWT) in patients with cystic fibrosis (CF), and to investigate the relation between echocardiographic findings and results of 6MWT, clinical scores, chest radiograph scores and lung function tests. DESIGN: This was a prospective cross-sectional study in patients with CF (16 years and older) with clinical stability, attending the Adult CF Program at the Hospital de Clínicas de Porto Alegre. The patients had Doppler echocardiography and performed a 6MWT. As well as pulmonary function tests and chest roentgenograms, and a clinical score was obtained for all patients. RESULTS: The study included 39 patients with a mean age of 23.7+/-6.3 years. There were no significant correlation between the distance walked and PASP, diameter of the right ventricle (DRV) and pulmonary acceleration time (p>0.05). We observed a significant correlation among PASP and the SpO(2) at rest (r=-0.73; p<0.001), SpO(2) at the end of the 6MWT (r= -0.45; p=0.006), clinical score (r= -0.55; p=0.001), chest radiograph score (r= -0.33; p=0.049), FEV1 (r= -0.63; p< 0.001), and FVC (r=-0.55; p=0.001). Right ventricular outflow tract flow acceleration time (Ac T) was significantly correlated only with the FEV1 (r=0.32; p=0.047). RVD was significantly correlated with SpO(2) at rest (r= -0.44; p=0.005) and clinical score (r= -0.38; p=0.017). The SpO(2) at rest was the single best predictor of PASP and this effect was independent of the relationship between other independent variables (p=0.001). The declining pulmonary function was significantly associated with PASP (p<0.001), SpO(2) at rest (p=0.001), SpO(2) at the end of the 6MWT (p=0.007) and difference between peripheral oxygen saturation at resting and at the end of the 6MWT (p=0.025). CONCLUSION: The PASP was not significantly correlated with the distance walked during the 6MWT in patients with CF. The PASP was strongly correlated with oxygen status at rest. The SpO(2) at rest was the best predictor of PASP. Also, PASP was strongly correlated with Shwachman-Kulczycki score, FEV(1), and FVC in this population.