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.

Genomovar status, virulence markers and genotyping of Burkholderia cepacia complex strains isolated from Brazilian cystic fibrosis patients.

Burkholderia cepacia complex isolates obtained by microbiological culture of respiratory samples from Brazilian CF patients were studied by recA based PCR, screened by specific PCR for virulence markers and genotyped by RAPD. Forty-one isolates of B. cepacia complex were identified by culture and confirmation of identity and genomovar determination obtained in 32 isolates, with predominance of B. cenocepacia (53.1%). Virulence markers were not consistently found among isolates. Genotyping did not identify identical patterns among different patients. B. cenocepacia was the most prevalent B. cepacia complex member among our patients, and cross-infection does not seem to occur among them.

Quality of life amongst adolescents and young adults with cystic fibrosis: correlations with clinical outcomes.

OBJECTIVES: The current study sought to evaluate the quality of life of young patients with cystic fibrosis and correlate these results with the clinical parameters indicative of disease severity. METHODS: This cross-sectional study applied the validated Portuguese version of a cystic fibrosis specific quality of life questionnaire to clinically stable patients aged 14 to 21 years old. The correlations between the questionnaire domain scores and forced expiratory volume in one second (FEV1) values, the Shwachman-Kulczycki score, and body mass index were assessed, and correlations were considered as significant when p<0.05. RESULTS: A total of 31 patients (11 females; 16.4±2.3 years old) were evaluated, and the median scores on the questionnaire domains ranged from 66.7 to 100. A significant correlation was found between body mass index and the weight (r=0.43, p=0.016) and the eating questionnaire domains (r=0.44, p=0.013); between FEV1 and the physical (r=0.53, p=0.002) and treatment burden (r=0.41, p=0.023) domains; and between the Shwachman-Kulczycki score and the physical (r=0.39, p=0.03), health (r=0.41, p=0.023), and role (r=0.37, p=0.041) domains. A significant difference was found amongst patients with FEV1 values above or below 60% of the predicted value with regard to the role and health domains. No differences in the scores were found according to gender. CONCLUSIONS: The current cystic fibrosis specific quality of life questionnaire scores exhibited wide variability across all domains; however, they indicated a relatively satisfactory quality of life amongst the patients studied. Certain domains exhibited significant correlations with clinical parameters; thus, this instrument has consistent associations with clinical outcomes.

Can inflammatory markers in induced sputum be used to detect phenotypes and endotypes of pediatric severe therapy-resistant asthma?

BACKGROUND: The phenotypes and endotypes of severe therapy-resistant asthma (STRA) have not been fully elucidated in children. The aim of the present study was to investigate inflammatory markers in the induced sputum of children with STRA and to compare them with those present in a group of children who achieved control. METHODS: A prospective cohort of children (6-18 years of age) diagnosed with severe asthma (GINA criteria) who had undergone treatment for at least 6 months was comprehensively followed for 3 months. Inhalation technique, adherence to treatment, ACT score, and main comorbidities were assessed. Induced sputum samples were collected for cytology analysis and quantitative assessment of cytokines; the participants also underwent spirometry, plethysmography, and fractional exhaled nitric oxide (FeNO) measurement. RESULTS: Forty patients were included (average age 12.8 years; 62.5% male); of these, 13 (32.5%) were classified as STRA at the end of follow-up. There were no significant differences between the STRA and control groups in demographic data, functional test results, or FeNO levels. The eosinophilic inflammatory pattern predominated in both groups; however, the STRA group showed a proportionally higher percentage of sputum neutrophils (P < 0.05). The median sputum levels of the cytokines IL-10, GM-CSF, IFN-γ, and TNF-α were significantly higher in the STRA group (P < 0.05). GM-CSF and TNF-α levels showed inverse correlations with ACT scores. CONCLUSION: The presence of neutrophils, the cytokines IL-10, and IFN-γ and, more particularly, TNF-α, and GM-CSF in the sputum may play an important role in the pathophysiological mechanism of STRA in children and adolescents. Specific antagonists for these cytokines may represent a future therapeutic strategy.

Diffuse alveolar hemorrhage in childhood-onset systemic lupus erythematosus: a severe disease flare with serious outcome.

OBJECTIVE: To evaluate prevalence, clinical manifestations, laboratory abnormalities and treatment in a multicenter cohort study including 847 childhood-onset systemic lupus erythematosus (cSLE) patients with and without diffuse alveolar hemorrhage (DAH), as well as concomitant parameters of severity. METHODS: DAH was defined as the presence of at least three respiratory symptoms/signs associated with diffuse interstitial/alveolar infiltrates on chest x-ray or high-resolution computer tomography and sudden drop in hemoglobin levels. Statistical analysis was performed using Bonferroni correction (p < 0.0022). RESULTS: DAH was observed in 19/847 (2.2%) cSLE patients. Cough/dyspnea/tachycardia/hypoxemia occurred in all cSLE patients with DAH. Concomitant parameters of severity observed were: mechanical ventilation in 14/19 (74%), hemoptysis 12/19 (63%), macrophage activation syndrome 2/19 (10%) and death 9/19 (47%). Further analysis of cSLE patients at DAH diagnosis compared to 76 cSLE control patients without DAH with same disease duration [3 (1-151) vs. 4 (1-151) months, p = 0.335], showed higher frequencies of constitutional involvement (74% vs. 10%, p < 0.0001), serositis (63% vs. 6%, p < 0.0001) and sepsis (53% vs. 9%, p < 0.0001) in the DAH group. The median of disease activity score(SLEDAI-2 K) was significantly higher in cSLE patients with DAH [18 (5-40) vs. 6 (0-44), p < 0.0001]. The frequencies of thrombocytopenia (53% vs. 12%, p < 0.0001), intravenous methylprednisolone (95% vs. 16%, p < 0.0001) and intravenous cyclophosphamide (47% vs. 8%, p < 0.0001) were also significantly higher in DAH patients. CONCLUSIONS: This was the first study to demonstrate that DAH, although not a disease activity score descriptor, occurred in the context of significant moderate/severe cSLE flare. Importantly, we identified that this condition was associated with serious disease flare complicated by sepsis with high mortality rate.

The combination of PCR and serology increases the diagnosis of Pseudomonas aeruginosa colonization/infection in cystic fibrosis.

BACKGROUND: Early diagnosis of Pseudomonas aeruginosa colonization/infection in patients with cystic fibrosis (CF) using microbiological culturing methods may be difficult. Serology and polymerase chain reaction (PCR) may be useful techniques for early detection of P. aeruginosa in children with CF. METHODS: A cross-sectional analysis comparing results obtained by three different methods for P. aeruginosa identification was performed in 87 CF patients with a mean age of 9.7 years. Microbiological culturing and PCR targeting the algD GDP mannose dehydrogenase gene of P. aeruginosa were performed in sputum or oropharyngeal swabs samples, and serum antibodies against three P. aeruginosa antigens (elastase, alkaline protease, and exotoxin A) were assessed once. RESULTS: It was possible to isolate P. aeruginosa by culture in samples from 42 patients (48.2%), while PCR was positive in 53 (60.9%) patients. Serology was positive in 38 patients (43.6%), with a higher positivity for elastase (37.9%), followed by alkaline protease (29.9%) and exotoxin A (19.5%). The difference among the three isolated methods was not statistically significant. The combination of PCR + serology was significantly superior to single methods, to PCR + culture and also to culture + serology. CONCLUSIONS: PCR identified a higher number of patients with P. aeruginosa than serology and conventional culture, but the difference did not reach statistical significance. Any of the combination methods that included PCR resulted in significantly statistical differences in relation to isolated microbiological or serology methods, but not to the PCR method alone, suggesting that PCR may be the main additive method for P. aeruginosa identification.

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.

Persistent symptoms and decreased health-related quality of life after symptomatic pediatric COVID-19: A prospective study in a Latin American tertiary hospital

OBJECTIVES: To prospectively evaluate demographic, anthropometric and health-related quality of life (HRQoL) in pediatric patients with laboratory-confirmed coronavirus disease 2019 (COVID-19) METHODS: This was a longitudinal observational study of surviving pediatric post-COVID-19 patients (n=53) and pediatric subjects without laboratory-confirmed COVID-19 included as controls (n=52) was performed. RESULTS: The median duration between COVID-19 diagnosis (n=53) and follow-up was 4.4 months (0.8-10.7). Twenty-three of 53 (43%) patients reported at least one persistent symptom at the longitudinal follow-up visit and 12/53 (23%) had long COVID-19, with at least one symptom lasting for >12 weeks. The most frequently reported symptoms at the longitudinal follow-up visit were headache (19%), severe recurrent headache (9%), tiredness (9%), dyspnea (8%), and concentration difficulty (4%). At the longitudinal follow-up visit, the frequencies of anemia (11% versus 0%, p=0.030), lymphopenia (42% versus 18%, p=0.020), C-reactive protein level of >30 mg/L (35% versus 0%, p=0.0001), and D-dimer level of >1000 ng/mL (43% versus 6%, p=0.0004) significantly reduced compared with baseline values. Chest X-ray abnormalities (11% versus 2%, p=0.178) and cardiac alterations on echocardiogram (33% versus 22%, p=0.462) were similar at both visits. Comparison of characteristic data between patients with COVID-19 at the longitudinal follow-up visit and controls showed similar age (p=0.962), proportion of male sex (p=0.907), ethnicity (p=0.566), family minimum monthly wage (p=0.664), body mass index (p=0.601), and pediatric pre-existing chronic conditions (p=1.000). The Pediatric Quality of Live Inventory 4.0 scores, median physical score (69 [0-100] versus 81 [34-100], p=0.012), and school score (60 [15-100] versus 70 [15-95], p=0.028) were significantly lower in pediatric patients with COVID-19 at the longitudinal follow-up visit than in controls. CONCLUSIONS: Pediatric patients with COVID-19 showed a longitudinal impact on HRQoL parameters, particularly in physical/school domains, reinforcing the need for a prospective multidisciplinary approach for these patients. These data highlight the importance of closer monitoring of children and adolescents by the clinical team after COVID-19.

[Induced sputum in children and adolescents with asthma: safety, clinical applicability and inflammatory cells aspects in stable patients and during exacerbation]. / Escarro induzido em crianças e adolescentes com asma: segurança, aplicabilidade clínica e perfil de células inflamatórias em pacientes estáveis e durante exacerbação.

OBJECTIVES: To determine the safety of sputum induction in asthmatic children and adolescents, to characterize sputum inflammatory cells while clinically stable and during exacerbation and to correlate sputum inflammatory cells with peripheral blood eosinophils, serum IgE and the degree of bronchial obstruction. METHODS: Ninety-six asthmatic patients aged 6 to 18 years were recruited for the present cross-sectional study. Spirometry was performed before and after administration of a bronchodilator. Sputum was collected spontaneously or after induction by the inhalation of saline solution at increasing concentrations. Blood samples were obtained for serum IgE and eosinophil quantification. RESULTS: Sputum samples adequate for analysis were obtained from 68 (70.8%) of the patients recruited. No relevant bronchoconstriction was observed during induction. The presence of a larger number of eosinophils in sputum did not correlate with more clinically severe asthma. No correlation was observed between the degree of bronchial obstruction, measured based on FEV1, and inflammatory cells in sputum, peripheral blood eosinophils or serum IgE. Larger numbers of neutrophils were observed in the asthma exacerbation group (p < 0.05). CONCLUSIONS: Sputum induction was found to be a safe procedure for obtaining clinical samples from children and adolescents even during exacerbations, allowing for clinical and functional limitations. The 67% induction success rate was considered satisfactory. In this group of patients, receiving inhaled corticosteroids, eosinophil quantification did not distinguish between the clinical and functional severity of asthma and was independent of the degree of airway obstruction. A proportional predominance of neutrophils was observed in the sputum of patients with asthma exacerbation.

Molecular epidemiology of Pseudomonas aeruginosa infections in a cystic fibrosis outpatient clinic.

Chronic respiratory infection by Pseudomonas aeruginosa is a significant determinant in the prognosis of cystic fibrosis patients. Cross-infection between cystic fibrosis patients and the prevalence of P. aeruginosa among them were investigated by microbiological surveillance and RAPD typing of the isolates. A total of 748 samples was cultured, including specimens from the respiratory tract (sputum or throat swabs) and hands of patients and medical staff, resulting in the collection of 86 isolates of P. aeruginosa from 65 samples. Prevalence of P. aeruginosa was 39.3% in respiratory samples, 0.2% on patients' hands and none in the medical staff's hand samples. RAPD typing characterised 51 genotypes and clonal persistence was observed in the majority of patients. These results suggest that cross-infection is not common in the outpatient clinic studied and a common source of acquisition is unlikely.

Identification of Pseudomonas aeruginosa, Burkholderia cepacia complex, and Stenotrophomonas maltophilia in respiratory samples from cystic fibrosis patients using multiplex PCR.

A multiplex PCR method was developed to identify P. aeruginosa, B. cepacia complex, and S. maltophilia directly in sputum and oropharyngeal samples from CF patients. One hundred and six patients (53 male, and 53 female) attending our pulmonology clinic were studied from September 2000-April 2001. Two hundred and fifty-seven samples were cultured in selective media and submitted to multiplex PCR reactions, using three primer pairs targeting specific genomic sequences of each species, with an additional primer pair targeting a stretch of ribosomal 16S DNA, universal for bacteria, to act as a control. P. aeruginosa was isolated by culture in 56% of samples, B. cepacia complex in 4.3%, and S. maltophilia in 2.7%, while multiplex PCR identified P. aeruginosa in 78.7%, B. cepacia complex in 3.9%, and S. maltophilia in 3.1% of samples. Multiplex PCR results were verified by PCR reactions using different species-specific primers described in the literature and DNA sequencing of amplicons from a few samples. Comparing to culture results, the sensitivity and specificity values of multiplex PCR for bacterial identification were, respectively, 97.2% and 45.5% for P. aeruginosa, 45.5% and 97.9% for B. cepacia complex, and 40% and 97.6% for S. maltophilia. All 10 multiplex PCR-positive results for B. cepacia complex were confirmed using other species-specific primers described in the literature, while this approach confirmed results for S. maltophilia identification in 7/8 samples (87.5%). Sequencing of amplicons from samples culture-negative but multiplex PCR-positive for P. aeruginosa and B. cepacia complex confirmed their identity, while minor nucleotide differences among amplicons ruled out the hypothesis of PCR contamination.

Use of selective medium for Burkholderia cepacia isolation in respiratory samples from cystic fibrosis patients.

Burkholderia cepacia colonizes cystic fibrosis (CF) patients. We evaluated the impact of the use of a selective medium in the rate of B. cepacia recovery from respiratory samples of CF patients. During a 6-month period, respiratory samples were collected from 106 CF patients and cultivated on selective media including a B. cepacia selective medium. Confirmation of the identity of B. cepacia isolates was carried out by species specific PCR and determination of genomovar status performed by a sequential PCR approach. Results of B. cepacia isolation during this period were compared to the preceding two years, when the sample processing was identical except for the lack of the B. cepacia selective medium. B. cepacia was isolated in 11/257 (4.2%) of the samples using the selective medium, in contrast with the preceding two years, when it was isolated in 6/1029 samples (0.58%), p < 0.0001. Identity of all 11 isolates was confirmed by PCR and genomovar determination was accomplished in all but one isolate. These results suggest that the use of a selective medium increases recovery rate of B. cepacia from respiratory samples.

Nutritional follow-up of cystic fibrosis patients: the role of nutrition education.

OBJECTIVE: To evaluate the nutritional status of a group of cystic fibrosis patients and establish the role of nutrition education addressed to them in a comparative study before and after intervention. METHODS: All cystic fibrosis patients in regular follow-up in the pulmonology clinic of Instituto da Crianca during 1996-99 were prospectively monitored for 3.5 years. Measurements of weight, height, mid upper arm circumference, skinfolds and calculations of weight/age, height/age, weight/height, mid upper arm circumference and triceps z scores, percentage of ideal weight for height, percentage of body fat, check of the use of enzymes with meals and of the use of nutritional supplements were performed at four points in time: initial (I), 7 (II), 13 (III) and 43 (IV) months after the first evaluation. Nutritional counseling was given both verbally and in writing (booklet) to all patients. RESULTS: Seventy-four patients, 38F/36M, age range 6 months to 18.4 years were evaluated. At study entry the anthropometric data showed: percentage of ideal weight for height = 94+/-13, percentage of body fat = 15+/-7.1, z scores for weight/age = -1.13+/-1.3, z scores for height/age = -0.94+/-1.2, z scores for weight/height = -0.69+/-1.1, z scores for mid upper arm circumference = -1.35+/-1.3, triceps z scores = -0.74+/-0.9. Compliance with enzyme therapy and use of high-calorie supplements improved during the study period. There was a significant increase in weight/height and triceps z scores and percentage of body fat throughout the study period. After stratifying patients into three age groups the anthropometric improvement was only significant among children under 5 years of age CONCLUSIONS: Mild malnutrition was present in this group of cystic fibrosis patients. The nutrition education led to an improvement in compliance with enzyme therapy, use of nutritional supplements and in nutritional status, mostly among the younger patients.

Acute bronchodilator responsiveness to tiotropium in postinfectious bronchiolitis obliterans in children.

BACKGROUND: Patients with postinfectious bronchiolitis obliterans (PIBO) usually have severe airflow obstruction and respond poorly to ß-adrenergic drugs. However, the bronchodilator response to an anticholinergic agent such as tiotropium bromide is not known. We studied the acute bronchodilator response to tiotropium for up to 24 h in children with PIBO using spirometric and plethysmographic criteria. METHODS: A randomized, double-blind, placebo-controlled, crossover, prospective study was performed in patients with stable PIBO, 6 to 16 years of age. Standard spirometry and plethysmography were performed before and at 30, 60, 120, and 180 min and 24 h after inhalation of 18 µg of tiotropium or a placebo. After 7 to 14 days, the drugs were inverted, and the procedures were repeated. The changes in lung function parameters at each time point were compared with the baseline by analysis of variance and Tukey posttest, and the differences in all time points assessments vs baseline in tiotropium vs placebo groups were compared using the Friedman test. RESULTS: A total of 30 patients were enrolled in the study (23 boys, seven girls; aged 10.9 ± 2.8 years) with baseline lung function values (% predicted) of FVC, FEV1, FEV1/FVC, forced expiratory flow between 25% and 75% of FVC (FEF25%-75%), total lung capacity (TLC), residual volume (RV), RV/TLC, airway resistance (Raw), and specific airway conductance (sGaw) of 75 ± 15, 48 ± 14, 59 ± 11, 22 ± 11, 120 ± 19, 281 ± 101, 49 ± 13, 250 ± 65, and 23 ± 9, respectively. Statistically significant differences were observed after tiotropium inhalation in the following parameters compared with baseline: FVC at 60, 120, and 180 min and 24 h; FEV1 at 30, 60, 120, and 180 min; FEV1/FVC at 60, 120, and 180 min; FEF25%-75% at 60, 120, and 180 min; RV at 30, 60, 120, and 180 min; TLC at 30, 120, and 180 min; RV/TLC at 30, 60, 120, and 180 min; Raw at 30, 60, 120, and 180 min and 24 h; and sGaw at 30, 60, 120, and 180 min and 24 h. For the placebo group, no significant differences were observed in any lung function parameters at any time. The differences in the main functional measurements between the tiotropium and placebo groups were statistically significant. CONCLUSIONS: Tiotropium acutely decreased airway obstruction and air trapping for up to 24 h in children with PIBO.

Quality of life amongst adolescents and young adults with cystic fibrosis: correlations with clinical outcomes

OBJECTIVES: The current study sought to evaluate the quality of life of young patients with cystic fibrosis and correlate these results with the clinical parameters indicative of disease severity. METHODS: This cross-sectional study applied the validated Portuguese version of a cystic fibrosis specific quality of life questionnaire to clinically stable patients aged 14 to 21 years old. The correlations between the questionnaire domain scores and forced expiratory volume in one second (FEV1) values, the Shwachman-Kulczycki score, and body mass index were assessed, and correlations were considered as significant when p<0.05. RESULTS: A total of 31 patients (11 females; 16.4±2.3 years old) were evaluated, and the median scores on the questionnaire domains ranged from 66.7 to 100. A significant correlation was found between body mass index and the weight (r=0.43, p=0.016) and the eating questionnaire domains (r=0.44, p=0.013); between FEV1 and the physical (r=0.53, p=0.002) and treatment burden (r=0.41, p=0.023) domains; and between the Shwachman-Kulczycki score and the physical (r=0.39, p=0.03), health (r=0.41, p=0.023), and role (r=0.37, p=0.041) domains. A significant difference was found amongst patients with FEV1 values above or below 60% of the predicted value with regard to the role and health domains. No differences in the scores were found according to gender. CONCLUSIONS: The current cystic fibrosis specific quality of life questionnaire scores exhibited wide variability across all domains; however, they indicated a relatively satisfactory quality of life amongst the patients studied. Certain domains exhibited significant correlations with clinical parameters; thus, this instrument has consistent associations with clinical outcomes.

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.

Six minute walk test Z score: correlations with cystic fibrosis severity markers.

BACKGROUND: The six-minute-walk-test (6MWT) has been increasingly used in cystic fibrosis (CF) patients. However, few studies in children have correlated 6MWT with current parameters used to evaluate CF severity. Moreover, no study transformed the values of distance walked from meters into Z scores to avoid bias like age and gender, which are sources of 6MWT variability. METHODS: A cross-sectional descriptive study was performed to analyze the correlations (Spearman) among forced expiratory volume in one second (FEV(1)), body mass index (BMI), chest radiography (CXR), chest tomography (CT), and 6MWT Z score (Z-6MWT). Clinically stable CF patients, aged 6-21 years, were included. RESULTS: 34 patients, 14F/20M, mean age 12.1±4.0 years were studied. The mean Z-6MWT was -1.1±1.106. The following correlations versus Z-6MWT were found: FEV(1) (r=0.59, r(2)=0.32, p=0.0002), BMI Z score (r=0.42, r(2)=0.17, p=0.013), CXR (r=0.34, r(2)=0.15, p=0.0472) and CT (r=-0.45, r(2)=0.23, p=0.0073). CONCLUSIONS: In conclusion there was a significant, but poor, correlation between the six minute walk test Z score and the cystic fibrosis severity markers currently in use.

Shwachman-Kulczycki score still useful to monitor cystic fibrosis severity.

INTRODUCTION: The Shwachman-Kulczycki score was the first scoring system used in cystic fibrosis to assess disease severity. Despite its subjectivity, it is still widely used. OBJECTIVE: To study correlations among forced expiratory volume in one second (FEV1), chest radiography, chest computed tomography, 6-minute walk test, and Shwachman-Kulczycki score in patients with cystic fibrosis and to test whether the Shwachman-Kulczycki score is still useful in monitoring the severity of the disease. METHODS: A cross-sectional prospective study was performed to analyze the correlations (Spearman). Patients with clinically stable cystic fibrosis, aged 3-21 years, were included. RESULTS: 43 patients, 19F/24M, mean age 10.5 + 4.7 years, with a median Shwachman-Kulczycki score of 70 were studied. The median Brasfield and Bhalla scores were 17 and 10, respectively. The mean Z score for the 6-minute walk test was -1.1 + 1.106 and the mean FEV1 was 59 + 26 (as percentage of predicted values). The following significant correlations versus the Shwachman-Kulczycki score were found: FEV1 (r = 0.76), 6-minute walk test (r = 0.71), chest radiography (r = 0.71) and chest computed tomography (r = -0.78). When patients were divided according to FEV1, a statistically significantly correlation with the Shwachman-Kulczycki score was found only in patients with FEV1 <70% (r = 0.67). CONCLUSIONS: The Shwachman-Kulczycki score remains an useful tool for monitoring the severity of cystic fibrosis, adequately reflecting the functional impairment and chest radiography and tomography changes, especially in patients with greater impairment of lung function. When assessing patients with mild lung disease its limitations should be considered and its usefulness in such patients should be evaluated in larger populations.

Primary ciliary dyskinesia: evaluation using cilia beat frequency assessment via spectral analysis of digital microscopy images.

Ciliary beat frequency (CBF) measurements provide valuable information for diagnosing of primary ciliary dyskinesia (PCD). We developed a system for measuring CBF, used it in association with electron microscopy to diagnose PCD, and then analyzed characteristics of PCD patients. The CBF measurement system was based on power spectra measured through digital imaging. Twenty-four patients suspected of having PCD (age 1-19 yr) were selected from a group of 75 children and adolescents with pneumopathies of unknown causes. Ten healthy, nonsmoking volunteers (age ≥ 17 yr) served as a control group. Nasal brush samples were collected, and CBF and electron microscopy were performed. PCD was diagnosed in 12 patients: 5 had radial spoke defects, 3 showed absent central microtubule pairs with transposition, 2 had outer dynein arm defects, 1 had a shortened outer dynein arm, and 1 had a normal ultrastructure. Previous studies have reported that the most common cilia defects are in the dynein arm. As expected, the mean CBF was higher in the control group (P < 0.001) and patients with normal ultrastructure (P < 0.002), than in those diagnosed with cilia ultrastructural defects (i.e., PCD patients). An obstructive ventilatory pattern was observed in 70% of the PCD patients who underwent pulmonary function tests. All PCD patients presented bronchial wall thickening on chest computed tomography scans. The protocol and diagnostic techniques employed allowed us to diagnose PCD in 16% of patients in this study.

Long-term home oxygen therapy in children and adolescents: analysis of clinical use and costs of a home care program.

OBJECTIVES: To describe the clinical and laboratory characteristics of patients on long-term home oxygen therapy followed up by the home care program of Hospital das Clínicas, School of Medicine, Universidade de São Paulo, during a period of 8 years; to compare groups with and without secondary pulmonary hypertension; and to estimate the cost of the program using oxygen concentrators vs. oxygen cylinders provided by the hospital. METHODS: A descriptive, retrospective cohort study of patients on long-term home oxygen therapy followed up from 2002 to 2009 at the Unit of Pulmonology, Children's Institute, Hospital das Clínicas, School of Medicine, Universidade de São Paulo. RESULTS: We studied 165 patients, of whom 53% were male, with the following medians: age at the beginning of oxygen therapy--3.6 years; duration of oxygen therapy--7 years; and survival time after beginning of oxygen therapy--3.4 years. The main diagnoses were: cystic fibrosis (22%), bronchopulmonary dysplasia (19%), and bronchiolitis obliterans (15%). Of the 33 patients who underwent spirometry, 70% had severe obstructive lung disease. Echocardiogram was performed in 134 patients; 51% of them had secondary pulmonary hypertension. There was a statistically significant association between pulmonary hypertension and need of higher oxygen flows (chi-square, p = 0.011), and between pulmonary hypertension and longer duration of oxygen therapy (Logrank, p = 0.0001). There was no statistically significant difference between survival time after the beginning of oxygen therapy and pulmonary hypertension. The average monthly costs of the program were US$ 7,392.93 for concentrators and US$ 16,630.92 for cylinders. CONCLUSIONS: Long-term home oxygen therapy was used to treat different chronic diseases, predominantly in infants and preschool children. There was a high frequency of pulmonary hypertension associated with longer periods of oxygen use and greater oxygen flow, without association with survival rate. The use of concentrators instead of cylinders may reduce costs significantly.