Cystic Fibrosis: A Simple and Customized Strategy for Genetic Screening Able to Detect Over 90% of Identified Mutated Alleles in Brazilian Newborns.

INTRODUCTION: The incorporation of molecular genetic testing into cystic fibrosis (CF) screening programs increases the specificity of the diagnostic strategy and has the potential to decrease the rate of false- positive results. In this sense, our objective was to develop a genotyping assay that could detect 25 pathogenic variants in the cystic fibrosis transmembrane conductance regulator (CFTR) gene with high sensitivity and that could be incorporated into the routine of newborn screening, complementing the current existing protocol used in our public health institution. METHODS: A mini-sequencing assay was standardized using single-base extension in a previously genotyped control sample. This strategy was validated in a Brazilian cohort of CF patients by Sanger sequencing. RESULTS: The inclusion of the 25 variants in the current newborn screening program increased the identification rates of two alleles from 33 to 52.43% in CF patients. This new approach was able to detect a total of 37 variants, which represents 93.01% of all mutated alleles described in the last CF Brazilian Register. CONCLUSIONS: Mini-sequencing for the simultaneous detection of 25 CFTR gene variants improves the screening of Brazilian newborns and decreases the number of inconclusive cases. This method uses minimal hands-on time and is suited for rapid screening, which reduces sample processing costs.

Six-Minute Walk Test Results Predict Risk of Hospitalization for Youths with Cystic Fibrosis: A 5-Year Follow-Up Study.

OBJECTIVE: To evaluate the association of 6-minute walk test (6MWT) and other variables (anthropometry, chronic Pseudomonas aeroginosa colonization, pulmonary function, and respiratory muscle strength) with the risk of hospitalization for pulmonary exacerbation in children and adolescents with cystic fibrosis (CF). STUDY DESIGN: Cohort study that included patients with CF aged 6-18 years. All participants underwent spirometry, manovacuometry, and 6MWT during the 5-year follow-up. Anthropometric and clinical data were collected and the time to first hospitalization, total days of hospitalization, and antibiotic use during follow-up was recorded. RESULTS: A total of 26 patients with CF, mean age 10.2 ± 2.8 years, were included. The group had mild impairment of lung function with a significant decline in forced expiratory volume in 1 second (P = .019) over the 5 years. Respiratory muscle strength and 6MWT proved to be preserved, although maximum inspiratory pressure increased (P < .001) and maximum expiratory pressure and 6-minute walk distance (6MWD) remained stable. There were inverse associations of 6MWD in meters (r = -0.813, P < .001) and z score (r = -0.417, P = .015) with total days of hospitalization. Moreover, there was a reduction in the risk of a first hospitalization (Cox HR 0.32; P = .037) in patients with a greater 6MWD. CONCLUSIONS: We found an association between the 6MWT and the risk of hospitalization in children and adolescents with CF. Furthermore, functional capacity apparently does not follow the expected decline in pulmonary function over time, whereas inspiratory muscle strength increases with disease progression.

Correlation Between Flexible Fiberoptic Laryngoscopic and Polysomnographic Findings in Patients with Mucopolysaccharidosis Type VI.

This study aimed to compare flexible fiberoptic laryngoscopy (FFL) and polysomnography (PSG) findings in patients with mucopolysaccharidosis (MPS) type VI and to describe upper airway anatomical findings and abnormal PSG results in these patients. In this cross-sectional study, all MPS VI patients followed up at the genetic division of a hospital in southern Brazil were included. Overnight PSG was performed, and the results were classified as normal or mildly, moderately, or severely abnormal. FFL was performed between 7 days before and 7 days after PSG. FFL findings were classified as (1) no obstruction, (2) mild obstruction, (3) moderate obstruction, or (4) severe obstruction of the airways, using the highest score obtained in all the regions.Eleven patients with MPS VI were included. FFL detected severe airway obstruction in eight (72.7%) patients, moderate obstruction in two (18.2%), and mild obstruction in one (9.1%). PSG revealed obstructive sleep apnea syndrome (OSAS) in nine (81.8%) patients. Among these, mild OSAS was observed in five (45.5%) patients, moderate OSAS in three (27.2%), and severe OSAS in one (9.1%). Moderate to severe hypertrophy of the nasal turbinates was found in 81.8% of the patients, and 64% had severe infiltration in the supraglottic region. There was no association between FFL and PSG findings (p = 0.454; κ = -0.09; 95%CI = -0.34 to 0.17), indicating no agreement between the two methods. In the present study, all patients with MPS showed some degree of airway obstruction. We suggest performing PSG in MPS patients to determine disease severity.

Inspiratory Muscle Strength and Endurance in Children and Adolescents with Cystic Fibrosis.

BACKGROUND: Pulmonary changes that occur in cystic fibrosis may influence inspiratory muscle strength and endurance. We evaluated inspiratory muscle strength and endurance in children and adolescents with cystic fibrosis in comparison with healthy subjects. METHODS: This is a cross-sectional observational study with subjects with cystic fibrosis and paired healthy individuals, age 6-18 y. Spirometry, impulse oscillometry, plethysmography, manovacuometry, and a protocol of inspiratory muscle endurance were performed. RESULTS: Subjects with cystic fibrosis (n = 34) had higher maximum percent-of-predicted inspiratory pressure (PImax) than healthy (n = 68) subjects (118.5 ± 25.8% vs 105.8 ± 18.0%) and no significant difference in endurance (60.9 ± 13.3% vs 65.3 ± 12.3%). When restricting the analysis to subjects without Pseudomonas aeruginosa colonization and with FEV1 > 80%, PImax values were significantly higher, and inspiratory muscle endurance was lower, in comparison with the control group. PImax correlated significantly with FVC (r = 0.44, P = .02) and FEV1 (r = 0.41, P = .02), whereas endurance correlated better with total airway resistance (r = 0.35, P = .045) and with central airway resistance (r = 0.48, P = .004). CONCLUSIONS: Children and adolescents with cystic fibrosis with no colonization by P. aeruginosa and normal lung function present increased inspiratory muscle strength and decreased endurance compared with healthy individuals, indicating that changes in the respiratory muscle function seem to be distinctly associated with pulmonary involvement. Strength was related to pulmonary function parameters, whereas endurance was associated with airway resistance.

Physical exercise recommendations improve postural changes found in children and adolescents with cystic fibrosis: a randomized controlled trial.

OBJECTIVE: To evaluate postural changes and the distribution of plantar pressures in patients with cystic fibrosis (CF). We also sought to evaluate the effects of an educational guideline for physical activity on body posture in children and adolescents with CF. STUDY DESIGN: This was a 2-phase study of individuals between age 7 and 20 years. Phase I was a cross-sectional study in which healthy subjects were selected for postural evaluation and baropodometry, aiming to perform a later comparison with patients with CF. In phase II, we performed a randomized controlled clinical trial to assess the influence of the exercise guideline on the postural changes. Patients were assigned to 2 groups: control and intervention. The intervention consisted of a handbook with instructions for aerobic exercise and stretching. Main outcomes were postural abnormalities, plantar pressure distribution, and lung function. RESULTS: In phase I, 34 patients with CF and 34 healthy matched individuals were included. No significant baseline differences were identified. Children with CF presented more postural deviations compared with healthy subjects (P < .05), as to alignment of the head, shoulder girdle, and pelvis, increased cervical lordosis, and lateral chest distance. In phase II (n = 34), there were no baseline differences between groups. The intervention caused (P < .05) a decrease in cervical lordosis, thoracic kyphosis, lumbar lordosis, lateral chest distance, and abdominal protrusion, as well as in the baropodometric mean pressure and contact area. CONCLUSIONS: Children and adolescents with CF present postural changes when compared with healthy individuals. The educational guideline for exercise practice helped to improve posture, preventing the progression of some postural disorders.

Effects of an educational intervention of physical activity for children and adolescents with cystic fibrosis: a randomized controlled trial.

BACKGROUND: Regular aerobic exercise in patients with cystic fibrosis (CF) improves aerobic conditioning and delays disease progression, resulting in better quality of life. The purpose of this study was to evaluate the effect of an aerobic exercise program based on verbal and written guidelines on maximum exercise capacity using a cardiopulmonary exercise test, quality of life, and the self-reported aerobic exercise practice of children and adolescents with CF. METHODS: This randomized controlled trial followed guidelines for physical exercise in a CF center. Subjects were assigned to 2 groups: intervention (group 1), with 17 subjects; and control (group 2), also with 17 subjects. Data were collected from October 2010 to October 2011, and the study population comprised 7-20-y-old children and adolescents with CF. The intervention consisted of handing out a manual with guidelines for aerobic physical exercises and reinforcing recommendations in telephone calls every 2 weeks. RESULTS: Thirty-four subjects were included in the study, 20 of whom were boys (58.5%). The groups were similar at baseline. In group 1, 6 subjects (35.2%) reported practicing physical exercises regularly. The mean age was 13.4 ± 2.8 y, the mean percent-of-predicted FEV1 was 95.5 ± 17.9%, and the mean peak oxygen uptake (V̇O2 ) relative to body mass was 34.9 ± 9.0 mL/kg/min. In group 2, 4 subjects (23.5%) reported practicing physical exercises regularly. The mean age was 12.7 ± 3.3 y, the mean percent-of-predicted FEV1 was 100.1 ± 21.2%, and the mean peak V̇O2 was 33.2 ± 8.2 mL/kg/min. In group 1, there was a significant increase in physical exercise practice as reported by subjects after 3 months of intervention compared with group 2 (P = .01). No statistically significant differences were found for the other variables. CONCLUSIONS: Verbal and written guidelines for aerobic exercise, together with supervision over the telephone, had a positive impact on the self-reported regular physical exercise practice of children and adolescents. However, no improvement was found in lung function and maximum exercise capacity or domains of the quality of life questionnaire.

Assessment of regulatory T cells in childhood immune thrombocytopenic purpura.

This study had the objective to assess the frequency of Tregs in children newly diagnosed with ITP and ascertain whether an association exists between Tregs and platelet counts, by means of a comparison with healthy controls. This case-control study included 19 patients newly diagnosed with ITP-whose blood samples were collected at four points in time: before any therapy and 1, 3, and 6 months after diagnosis-and 19 healthy controls. Tregs (CD4(+) CD25(+)Foxp3 T cells) were evaluated by flow cytometry. There was a statistically significant difference in platelet count between the case and control groups. There were no significant differences in Treg counts between cases and controls at any point during the course of the study and no difference in Treg counts between the chronic and nonchronic groups and no significant correlation between Tregs and platelet counts in the case and control groups. The findings of this study did not show any statistically significant correlation between Tregs and number of platelets in the case and control groups. Treg cells did not play a role in the regulation of autoimmunity in children with ITP.

Fatores de risco para necessidade de ventilação mecânica em crianças com Influenza A(H1N1)pdm09 / Risk factors for need of mechanical ventilation in children with Influenza A(H1N1)pdm09

OBJETIVO: A pandemia causada pelo vírus Influenza A(H1N1)pdm09 teve seu pico nos meses de julho e agosto de 2009, no Sul do Brasil, sendo a incidência mais alta em crianças e adultos jovens. No período pós-pandêmico, no Brasil, houve aumento de casos nos meses de inverno dos anos de 2011 e 2012, de forma semelhante ao vírus influenza sazonal. Como ainda estão ocorrendo infecções devido ao influenza pandêmico, nosso objetivo foi investigar fatores de risco para pior desfecho em crianças. MÉTODOS: Foi realizado um estudo de coorte retrospectivo analisando as fichas de pacientes menores de 14 anos hospitalizados e com RT-PCR positiva para Influenza A(H1N1)pdm09 durante a primeira onda , em seis centros terciários brasileiros. Definimos a necessidade de ventilação mecânica como desfecho com gravidade e, como possíveis preditores, os fatores idade, doenças crônicas, codetecção bacteriana e viral, achados da radiografia do tórax e uso de oseltamivir. RESULTADOS: No presente estudo, foram incluídos120 pacientes. Em uma análise multivariada, doenças crônicas (razão de prevalência: 2,613; intervalo de confiança de 95%: 1,267 a 5,386) e codetecção viral (razão de prevalência: 2,43; intervalo de confiança de 95%: 1,203 a 4,905) se associaram estatisticamente a um pior desfecho (p < 0,05). CONCLUSÕES: A presença de doenças crônicas como preditores reforça evidências prévias. Além disso, verificamos que a codetecção viral é fator de risco. São necessários outros estudos para confirmar essa associação.

OBJECTIVE: The pandemic caused by influenza A(H1N1)pdm09 virus peaked between July and August of 2009 in southern Brazil, with the highest incidence in children and young adults. In the post-pandemic period, there was an increase in the incidence of cases during the winter months of 2011 and 2012 in Brazil, similar to seasonal influenza virus. Since infections due to pandemic influenza are still occurring, the present study aimed to investigate the risk factors for worse outcome in children. METHODS: A retrospective cohort study was performed by reviewing the charts of hospitalized patients younger than 14 years with reverse transcription-polymerase chain reaction (RT-PCR) positive for influenza A(H1N1)pdm09 during the first pandemic wave in six Brazilian tertiary centers. Need for mechanical ventilation was defined as the severity of outcome; age, chronic diseases, bacterial and viral co-detection, chest radiograph findings, and use of oseltamivir were possible predictors. RESULTS: In the present study, 120 patients were included. In a multivariate analysis, chronic diseases (prevalence ratio: 2.613, 95% CI: 1.267-5.386) and viral co-detection (prevalence ratio: 2.43, 95% CI: 1.203-4.905) were statistically associated with worse outcome (p < 0.05). CONCLUSIONS: The presence of chronic diseases as predictors reinforces previous finding. Furthermore, viral co-detection was found to be a risk factor. Further studies are necessary to confirm this association.

Risk factors for need of mechanical ventilation in children with influenza A(H1N1)pdm09.

OBJECTIVE: The pandemic caused by influenza A(H1N1)pdm09 virus peaked between July and August of 2009 in southern Brazil, with the highest incidence in children and young adults. In the post-pandemic period, there was an increase in the incidence of cases during the winter months of 2011 and 2012 in Brazil, similar to seasonal influenza virus. Since infections due to pandemic influenza are still occurring, the present study aimed to investigate the risk factors for worse outcome in children. METHODS: A retrospective cohort study was performed by reviewing the charts of hospitalized patients younger than 14 years with reverse transcription-polymerase chain reaction (RT-PCR) positive for influenza A(H1N1)pdm09 during the first pandemic wave in six Brazilian tertiary centers. Need for mechanical ventilation was defined as the severity of outcome; age, chronic diseases, bacterial and viral co-detection, chest radiograph findings, and use of oseltamivir were possible predictors. RESULTS: In the present study, 120 patients were included. In a multivariate analysis, chronic diseases (prevalence ratio: 2.613, 95% CI: 1.267-5.386) and viral co-detection (prevalence ratio: 2.43, 95% CI: 1.203-4.905) were statistically associated with worse outcome (p<0.05). CONCLUSIONS: The presence of chronic diseases as predictors reinforces previous finding. Furthermore, viral co-detection was found to be a risk factor. Further studies are necessary to confirm this association.

Bone mineral density, pulmonary function, chronological age, and age at diagnosis in children and adolescents with cystic fibrosis.

OBJECTIVE: To assess bone mineral density in patients with cystic fibrosis (CF), and to correlate it with possible intervening variables. METHODS: Children and adolescents diagnosed with CF, aged 6 to 18 years, followed at the outpatient clinic were included in the study. First, demographic data were collected and, subsequently, patients underwent a spirometric test. All patients answered the Cystic Fibrosis Quality of Life Questionnaire (CFQ) and underwent the six-minute walk test (6MWT) and bone densitometry (DXA). RESULTS: A total of 25 CF patients were included, of which 56% were males. The mean age was 12.3±3.4 years; mean height was 149.2±14.4 cm; and mean weight was 44.4±13.9 kg. Most results on pulmonary function and bone mineral density (BMD) were within normal limits. The mean forced expiratory volume in one second (FEV) was 92.5±23.6 (% of predicted), mean forced vital capacity (FVC) was 104.4±21.3 (% of predicted), and1 mean BMD z-score was 0.1±1.0. BMD was moderately correlated with FEV (r = 0.43, p = 0.03) and FVC (r = 0.57, p = 0.003). Regarding chronological age and age at diagnosis, a moderate and inverse correlation was also found (r = -0.55, p = 0.004; r = -0.57, p = 0.003, respectively). However, no significant correlations were found with the data from CFQ, 6MWT, and body mass index. CONCLUSION: Most patients had BMD within normal limits and presented a positive correlation with pulmonary function, as well as a negative correlation with chronological age and age at diagnosis.

Densidade mineral óssea, função pulmonar, idade cronológica e idade de diagnóstico em crianças e adolescentes com fibrose cística / Bone mineral density, pulmonary function, chronological age, and age at diagnosis in children and adolescents with cystic fibrosis

OBJETIVO: Avaliar a densidade mineral óssea de pacientes com fibrose cística (FC) e correlacioná-la com possíveis variáveis intervenientes. MÉTODOS: Foram incluídos crianças e adolescentes com diagnóstico clínico de FC, idade entre seis e dezoito anos, e em acompanhamento ambulatorial. Primeiramente, foram coletados os dados demográficos, para posterior realização do teste espirométrico. Todos os pacientes responderam ao questionário de qualidade de vida em FC (QFC) e realizaram o teste de caminhada dos seis minutos (TC6) e o exame de densitometria óssea (DXA). RESULTADOS: Foram incluídos 25 pacientes fibrocísticos, sendo 56% do sexo masculino. A média de idade foi de 12,3 ± 3,4 anos, altura de 149,2 ± 14,4 cm e peso de 44,4 ± 13,9 kg. A maioria dos dados de função pulmonar e de densidade mineral óssea (DMO) encontrou-se dentro dos limites de normalidade. A média do volume expiratório forçado no primeiro segundo (VEF1) foi de 92,5 ± 23,6 (% do previsto), capacidade vital forçada (CVF) de 104,4 ± 21,3 (% do previsto) e o escore z da DMO de 0,1 ± 1,0. A DMO correlacionou-se de forma moderada com o VEF1 (r = 0,43; p = 0,03) e com a CVF (r = 0,57; p = 0,003). Em relação à idade cronológica e à idade de diagnóstico, também foi encontrada uma correlação moderada e inversa (r = -0,55; p = 0,004 /r = -0,57; p = 0,003, respectivamente). Entretanto, não foram encontradas correlações significativas com os dados do QFC, TC6 e índice de massa corporal. CONCLUSÃO: A maioria dos pacientes avaliados apresenta DMO dentro dos limites de normalidade e possui correlação positiva com a função pulmonar e negativa com a idade cronológica e a idade de diagnóstico.

OBJECTIVE: To assess bone mineral density in patients with cystic fibrosis (CF), and to correlate it with possible intervening variables. METHODS: Children and adolescents diagnosed with CF, aged 6 to 18 years, followed at the outpatient clinic were included in the study. First, demographic data were collected and, subsequently, patients underwent a spirometric test. All patients answered the Cystic Fibrosis Quality of Life Questionnaire (CFQ) and underwent the six-minute walk test (6MWT) and bone densitometry (DXA). RESULTS: A total of 25 CF patients were included, of which 56% were males. The mean age was 12.3±3.4 years; mean height was 149.2±14.4 cm; and mean weight was 44.4±13.9 kg. Most results on pulmonary function and bone mineral density (BMD) were within normal limits. The mean forced expiratory volume in one second (FEV1) was 92.5±23.6 (% of predicted), mean forced vital capacity (FVC) was 104.4±21.3 (% of predicted), and mean BMD z-score was 0.1±1.0. BMD was moderately correlated with FEV1 (r = 0.43, p = 0.03) and FVC (r = 0.57, p = 0.003). Regarding chronological age and age at diagnosis, a moderate and inverse correlation was also found (r = -0.55, p = 0.004 ; r = -0.57, p = 0.003, respectively). However, no significant correlations were found with the data from CFQ, 6MWT, and body mass index. CONCLUSION: Most patients had BMD within normal limits and presented a positive correlation with pulmonary function, as well as a negative correlation with chronological age and age at diagnosis.

Nutritional status, breastfeeding, and evolution of Infants with acute viral bronchiolitis.

Acute viral bronchiolitis is a common respiratory infectious disease of infancy. A prospective study was carried out with 175 infants aged up to six months to evaluate their nutritional and breastfeeding status as possible risk factors for unfavourable evolution of previously-healthy infants from a care hospital. Immunofluorescence test for virus and anthropometric assessment were performed. Outcomes were length of oxygen-use, length of hospital stay, and type of hospital unit needed. Seventy-three percent of the infants were well-nourished, 6% undernourished, 8.6% at a nutritional risk, 10.9% overweight, and 1.7% obese. Eighty-one percent of the undernourished and nutritionally at-risk infants and 72% of the well-nourished, overweight, and obese infants did not receive exclusive breastfeeding. The median length of hospital stay was four days and of oxygen-use was 60 hours. The nutritional status did not affect the clinical course of previously-healthy infants with acute viral brochiolitis. The duration of exclusive breastfeeding, but not type of breastfeeding, was inversely related to the length of oxygen-use and the length of hospital stay. Shorter exclusive breastfeeding was observed in infants who were assigned to a paediatric ward or to an intensive care unit. In conclusion, longer duration of breastfeeding was associated with better clinical outcomes.

Community-acquired pneumonia.

Pneumonia is highly prevalent in both developed and developing countries. In this review we list the main organisms affecting children with pneumonia and we propose a summary of the best possible diagnostic and therapeutic measures.

Spirometry in 3- to 6-year-old children with cystic fibrosis.

Spirometry is routinely used to assess pulmonary function of older children and adults with cystic fibrosis (CF); however, few data exist concerning the preschool age group. We have reported normative spirometric data for 3- to 6-year-old children. The current study was designed to assess a similarly aged group of clinically stable patients with CF. Thirty-three of 38 children with CF were able to perform 2 or 3 technically acceptable maneuvers. These patients had significantly decreased FVC, FEV(1), FEV(1)/FVC, and FEF(25-75) when expressed as z scores (number of SD from predicted): -0.75 +/- 1.63, -1.23 +/- 1.97, -0.87 +/- 1.33, and -0.74 +/- 1.63, respectively. There were significant positive correlations of the Brasfield radiological score with FVC and FEV(1) z scores (r(2) = 0.26, p < 0.01 and r(2) = 0.24, p < 0.01). In addition, homozygous patients for the DeltaF508 mutation had lower z scores for FVC (-1.21 versus 0.47, p < 0.01) and FEV(1) (-1.38 versus 0.21, p < 0.05) than heterozygous patients. Of the 14 patients who had full flow-volume spirometric measurements during infancy, 10 had FEF(25-75) z scores greater than -2 at both evaluations. Our findings suggest that spirometry can successfully be used to assess lung function in preschool children with CF and has the potential for longitudinal assessment from infancy through adulthood.