RESUMEN
Severe asthma patients with persistent airflow obstruction are characterized by functional obstruction due to mucus plugs containing mucins, fibrin, and eosinophil derived Charcot- Leyden crystals. The molecular mechanisms underlying this endotype are not clearly understood. Developing new models is crucial to respiratory research insofar as critical differences exist between human and rodent airway epithelium. We (and other teams) have shown that it is possible to reconstitute in vitro a complex and functional airway epithelium displaying all the features described in vivo from human-induced pluripotent stem cells (hiPSC). Our aim is to establish a human in vitro model of severe asthma that will recapitulate airway epithelium remodeling and mucus plugs.
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Asma , Células Madre Pluripotentes Inducidas , Humanos , Pulmón , MocoRESUMEN
Acid sphingomyelinase deficiency (ASMD), also called Niemann-Pick disease, is a storage disorder with pulmonary involvement but few respiratory symptoms in adults. However, the disease may evolve towards clinically relevant respiratory symptoms with referral to the pulmonologist for management and care. Based on two case reports illustrating respiratory impairment, the aim of this work was to review clinical features, diagnosis, respiratory prognostic and therapeutics for the pulmonologist. Overall, storage disorder should be suspected in the presence of hepatosplenomegaly and interstitial lung disease. Concomitant thrombopenia or hyperlipidemia should also draw attention. Following recent consensus guidelines, diagnosis is based on enzyme assay for ASM activity in blood, with subsequent gene sequencing once the biochemical diagnosis has been confirmed. Disease is slowly progressive and the main causes of death are respiratory and liver failure. Presence of emphysema lesions or worsening of respiratory symptoms should call for the intensification of treatment. Though enzyme replacement therapy is a promising way of development, lung transplantation might be considered for these patients in the absence of contraindication.
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Enfermedades de Niemann-Pick/complicaciones , Enfermedades de Niemann-Pick/terapia , Insuficiencia Respiratoria/etiología , Insuficiencia Respiratoria/terapia , Adulto , Terapia de Reemplazo Enzimático , Humanos , Enfermedades Pulmonares Intersticiales/diagnóstico , Enfermedades Pulmonares Intersticiales/etiología , Enfermedades Pulmonares Intersticiales/terapia , Trasplante de Pulmón , Masculino , Persona de Mediana Edad , Enfermedades de Niemann-Pick/diagnóstico , Guías de Práctica Clínica como Asunto , Neumólogos , Derivación y Consulta , Insuficiencia Respiratoria/diagnósticoRESUMEN
Obstructive sleep apnoea (OSA) is common in the general population, particularly in the elderly. This syndrome is frequently responsible for severe cardiovascular complications. However, the indications for its treatment in the elderly remain controversial. We report the case of a 79-year-old man with severe, undiagnosed OSA who inhaled his fixed dental bridge during sleep. The inhaled foreign body came to rest in the lumen of the left main stem bronchus. The association of obesity with a body mass index of 30kg/m2, snoring with breathing pauses reported by his partner, nocturia, morning headache and an Epworth score of 11 led to polysomnography which confirmed OSA with an apnoea/hypopnoea index of 53 per hour. This case report emphasises that OSA may constitute a risk fact for foreign body inhalation in elderly subjects due to arousal-induced hyperventilation following the apnoeic event.
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Dentadura Parcial Fija , Cuerpos Extraños/diagnóstico , Pulmón/patología , Apnea Obstructiva del Sueño/complicaciones , Anciano , Dentadura Parcial Fija/efectos adversos , Cuerpos Extraños/etiología , Humanos , Masculino , Obesidad/complicaciones , Obesidad/patología , Apnea Obstructiva del Sueño/patología , Ronquido/complicaciones , Ronquido/patologíaRESUMEN
INTRODUCTION: Type 1 neurofibromatosis, also called "Recklinghausen's disease" is among the most frequent autosomal dominant genetic disorders, with an incidence of 1:3500 births. It mainly affects the skin and peripheral nervous system. However, in its less frequent manifestations, are tumors such as meningocele and skeletal dysplasias leading to severe clinical presentation. CASE REPORT: We report the case of a 55-year-old patient with type 1 neurofibromatosis and dyspnea due to a large left thoracic meningocele combined with a significant kyphoscoliosis, causing a severe restrictive ventilatory defect, complicated by chronic respiratory failure and pulmonary hypertension. Symptomatic treatment with non-invasive ventilation permitted an improvement of the clinical situation. CONCLUSIONS: Our observation shows the complexity of the therapeutic support of the neurofibromatosis of type 1. The contribution of non-invasive ventilation was illustrated by the arterial blood gas and clinical improvements as well as improved quality of life, with an acceptable level of inconvenience to the patient.
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Disnea/diagnóstico , Disnea/etiología , Neurofibromatosis 1/complicaciones , Neurofibromatosis 1/diagnóstico , Insuficiencia Respiratoria/diagnóstico , Femenino , Humanos , Hipertensión Pulmonar/diagnóstico , Hipertensión Pulmonar/etiología , Meningocele/diagnóstico , Meningocele/etiología , Persona de Mediana Edad , Radiografía Torácica , Insuficiencia Respiratoria/etiología , Enfermedades Torácicas/diagnóstico , Enfermedades Torácicas/etiologíaRESUMEN
Summary: Different phenotypes of allergic rhinitis have been identified based on the seasonality of the allergen involved. Within pollinosis, importance has to be paid to the responsible pollen species. Guidelines for clinical management are mostly based on studies performed in patients with grass pollen allergy. Only few data is available on tree pollen allergy and more specifically on cypress pollen allergy. We focused on the clinical and biological features of cypress pollen allergy to determine whether it is associated with a specific phenotype of allergic rhinitis or not. Our results suggest that cypress pollen can be responsible for two distinct phenotypes of rhinitis, both different from other pollinosis. In the most common phenotype, cypress pollen was not responsible for bronchial hyperresponsiveness or systemic inflammation. Close attention has to be paid to the allergen involved in allergic rhinitis. Different phenotypes leading to different pharmacological strategies may apply.
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Hiperreactividad Bronquial/inmunología , Cupressus/inmunología , Inflamación/inmunología , Rinitis Alérgica Estacional/inmunología , Rinitis Alérgica/inmunología , Adulto , Alérgenos/inmunología , Femenino , Humanos , Inmunoglobulina E/metabolismo , Masculino , Persona de Mediana Edad , Fenotipo , Poaceae/inmunología , Polen/inmunología , Guías de Práctica Clínica como Asunto , Estaciones del Año , Adulto JovenRESUMEN
INTRODUCTION: We studied the pattern changes over time of medication prescriptions for COPD and their conformity with French and international recommendations using data from patients in the prospective French cohort "Initiatives BPCO". METHOD: Eight hundred and forty-six patients have been included during a first period from August, 2001 till May 2006 (n=425) and a second period from June, 2006 till June, 2012 (n=421). The pivotal date was based on the tiotropium availability in France. RESULTS: During period 1, we recruited older patients (average 65 vs 64 years), less often women (19 vs 26 %) and having less severe airflow obstruction (mean FEV1 48 vs 54 %). The ICS prescriptions decreased in mild COPD, but there was no change for inhaled long-acting beta-2 agonist (LABA) (68 %). The use of LABA+LAMA association without ICS increased from 0.9 to 7 %, but remained lower than the fixed LABA+ICS association (26 %), less often prescribed than the triple association LABA+ICS+LAMA (32.5 % in period 2). The use of long-acting bronchodilators increased from 68 to 80 % between both periods. Vaccinations and rehabilitation remained insufficiently prescribed. LAMA had been added but did not appear to replace other drugs.
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Broncodilatadores/uso terapéutico , Antagonistas Muscarínicos/administración & dosificación , Antagonistas Muscarínicos/farmacocinética , Pautas de la Práctica en Medicina/tendencias , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Administración por Inhalación , Anciano , Disponibilidad Biológica , Broncodilatadores/farmacocinética , Preparaciones de Acción Retardada , Femenino , Francia/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Pautas de la Práctica en Medicina/estadística & datos numéricos , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/metabolismoRESUMEN
BACKGROUND: Some studies suggest that asthma-COPD overlap syndrome (ACOS) is associated with worse outcomes than chronic obstructive pulmonary disease (COPD). The goal of this study was to further explore the clinical characteristics and survival of patients with ACOS identified in a real-life cohort of patients with COPD. METHODS: Data from the French COPD cohort 'INITIATIVES BronchoPneumopathie Chronique Obstructive' (n = 998 patients) were analyzed to assess the frequency of ACOS defined as a physician diagnosis of asthma before the age of 40 years and to analyze its impact. Univariate analyses were performed to assess the relationship between ACOS and sociodemographic characteristics, risk factors (smoking, occupational exposure, atopic diseases), symptoms (chronic bronchitis, dyspnea-modified Medical Research Council scale and baseline dyspnea index), quality of life (QoL), mood disorders, exacerbations, comorbidities, lung function, prescribed treatment, and survival. RESULTS: ACOS was diagnosed in 129 patients (13%). In multivariate analyses, ACOS was associated negatively with cumulative smoking (odds ratio [OR]: 0.992; 95% CI 0.984-1.000 per pack-year) and positively with obesity: OR: 1.97 [1.22-3.16], history of atopic disease (hay fever: OR: 5.50 [3.42-9.00] and atopic dermatitis: OR 3.76 [2.14-6.61]), and drug use (LABA + ICS: 1.86 [1.27-2.74], antileukotrienes 4.83 [1.63-14.34], theophylline: 2.46 [1.23-4.91], and oral corticosteroids: [2.99;.1.26-7.08]). No independent association was found with dyspnea, QoL, exacerbations, and mortality. CONCLUSIONS: Compared to 'pure' COPD patients, patients with ACOS exhibit lower cumulative smoking, suffer more from obesity and atopic diseases, and use more asthma treatments. Disease severity (dyspnea, QoL, exacerbations, comorbidities) and prognosis (mortality) are not different from 'pure' COPD patients.
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Asma/complicaciones , Asma/diagnóstico , Fenotipo , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Anciano , Asma/tratamiento farmacológico , Asma/epidemiología , Estudios de Cohortes , Comorbilidad , Diagnóstico Diferencial , Progresión de la Enfermedad , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Calidad de Vida , Factores de Riesgo , Encuestas y Cuestionarios , Evaluación de Síntomas , SíndromeRESUMEN
Inconsistent results have been reported regarding IL-5 blockade treatment in asthma. There were no direct between-treatment comparisons. Only differences between each drug and placebo were studied. We identified all RCTs with anti-IL5 treatments for patients with asthma over the 1990-September 2015 period. RCTs were searched on Medline, Cochrane and Embase. At least 50 patients were enrolled in each study. Outcomes considered were exacerbation rate reduction, FEV1 changes, ACQ-5 improvement, adverse events and serious adverse events. A global meta-analysis was first conducted followed by an indirect comparison of each IL-5-targeting drug: benralizumab, reslizumab and mepolizumab. Further eosinophilic subgroup analysis and sensitivity analysis were also conducted in case of heterogeneity. Ten trials involving 3421 patients were eligible for meta-analysis. IL-5 blockade significantly reduced annual exacerbation rates vs. placebo by 40% [29-50] (P < 0.01, I2 = 0.61). ACQ-5 was significantly improved vs. placebo but below the recognized MCID level (-0.31 [-0.41, -0.21], P < 0.01, I2 = 0.11). FEV1 changes from baseline were improved vs. placebo by 0.09 L [0.05-0.12] (P < 0.01, I2 = 0.28). The subgroup analysis identified a slight additional improvement in mean treatment effects in eosinophilic (> 300 mm3 /L) patients with severe asthma. Similar patterns and rates of adverse events and severe adverse events were reported with the three drugs. The data interpretations were not affected by the sensitivity analysis. IL-5 blockade appears to be a relevant treatment strategy to improve severe asthma management, particularly for eosinophilic patients. No clear superiority appeared between the drugs when appropriate doses were compared.
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Antiasmáticos/uso terapéutico , Anticuerpos Monoclonales/uso terapéutico , Asma/tratamiento farmacológico , Interleucina-5/antagonistas & inhibidores , Antiasmáticos/administración & dosificación , Antiasmáticos/efectos adversos , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/efectos adversos , Asma/diagnóstico , Asma/inmunología , Asma/metabolismo , Biomarcadores , Progresión de la Enfermedad , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Pruebas de Función Respiratoria , Índice de Severidad de la Enfermedad , Resultado del TratamientoAsunto(s)
Asma/terapia , Monitoreo Fisiológico/normas , Neumología/normas , Adolescente , Adulto , Niño , Progresión de la Enfermedad , Francia , Humanos , Monitoreo Fisiológico/métodos , Neumología/métodos , Neumología/organización & administración , Sociedades Médicas/organización & administración , Sociedades Médicas/normas , Adulto JovenAsunto(s)
Asma/terapia , Monitoreo Fisiológico/normas , Neumología/normas , Adolescente , Adulto , Niño , Progresión de la Enfermedad , Francia , Humanos , Monitoreo Fisiológico/métodos , Neumología/métodos , Sociedades Médicas/organización & administración , Sociedades Médicas/normas , Adulto JovenRESUMEN
BACKGROUND: Asthma is a biologically heterogeneous disease and development of novel therapeutics requires understanding of pathophysiologic phenotypes. There is uncertainty regarding the stability of clinical characteristics and biomarkers in asthma over time. This report presents the longitudinal stability over 12 months of clinical characteristics and clinically accessible biomarkers from ADEPT. METHODS: Mild, moderate, and severe asthma subjects were assessed at 5 visits over 12 months. Assessments included patient questionnaires, spirometry, bronchodilator reversibility, fractional exhaled nitric oxide (FENO), and biomarkers measured in induced sputum. RESULTS: Mild (n = 52), moderate (n = 55), and severe (n = 51) asthma cohorts were enrolled from North America and Western Europe. For all clinical characteristics and biomarkers, group mean data showed no significant change from visit to visit. However, individual data showed considerable variability. FEV1/FVC ratio showed excellent reproducibility while pre-bronchodilator FEV1 and FVC were only moderately reproducible. Of note bronchodilator FEV1 reversibility showed low reproducibility, with the nonreversible phenotype much more reproducible than the reversible phenotype. The 7-item asthma control questionnaire (ACQ7) demonstrated moderate reproducibility for the combined asthma cohorts, but the uncontrolled asthma phenotype (ACQ7 > 1.5) was inconstant in mild and moderate asthma but stable in severe asthma. FENO demonstrated good reproducibility, with the FENO-low phenotype (FENO < 35 ppb) more stable than the FENO-high phenotype (FENO ≥ 35 ppb). Induced sputum inflammatory phenotypes showed marked variability across the 3 sputum samples taken over 6 months. CONCLUSIONS: The ADEPT cohort showed group stability, individual stability in some parameters e.g. low FEV1/FVC ratio, and low FENO, but marked individual variability in other clinical characteristics and biomarkers e.g. type-2 biomarkers over 12 months. This variability is possibly related to seasonal variations in climate and allergen exposure, medication changes and acute exacerbations. The implications for patient selection strategies based on clinical biomarkers may be considerable.
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Asma/tratamiento farmacológico , Pruebas de Función Respiratoria/estadística & datos numéricos , Esputo/citología , Adulto , Asma/epidemiología , Biomarcadores , Broncodilatadores/uso terapéutico , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , América del Norte/epidemiología , Prevalencia , Reproducibilidad de los Resultados , Factores de Riesgo , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Resultado del TratamientoRESUMEN
BACKGROUND: In asthma, inflammation affects both the proximal and distal airways and may induce significant hyperinflation (HI). This study sought to evaluate the prevalence of HI in asthmatic patients with poorly controlled disease and/or dyspnea. METHODS: Poor asthma control was defined by an Asthma Control Test (ACT) score <20 (n = 287), and dyspnea was defined as a modified Medical Research Council score ≥1 (n = 18). HI was defined as either a residual volume/total lung capacity (RV/TLC) above the upper limit of normal (RV-HI) or a functional residual capacity (FRC) >120% predicted (FRC-HI). HI reversibility after administration of salbutamol (400 µg) was defined as a decrease in RV >20% or a reduction in FRC >10%. Changes in dyspnea and chest tightness were evaluated on a visual analogue scale. RESULTS: Both RV-HI and FRC-HI were observed in 48% of the 305 patients (mean ± SD age: 49 ± 17; FEV1 : 75 ± 18% predicted) included in the study. The prevalence of HI was higher in patients with a FEV1 <60% predicted (93% for RV-HI and 71% for FRC-HI, vs 21% and 41% in patients with a FEV1 > 80%). In patients with HI, the ACT score was lower and chest tightness higher. HI reversibility was obtained in 38% of the asthmatics with FRC-HI and 29% of the asthmatics with RV-HI, whereas FEV1 reversibility was obtained in half of these patients. CONCLUSIONS: HI is highly prevalent in poorly controlled asthmatics suggesting small airway dysfunction and may represent an additional criteria for evaluating responsiveness to bronchodilators.
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Asma/epidemiología , Asma/fisiopatología , Disnea/fisiopatología , Hiperventilación/fisiopatología , Adulto , Anciano , Albuterol/uso terapéutico , Asma/tratamiento farmacológico , Progresión de la Enfermedad , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Pruebas de Función Respiratoria , Factores de RiesgoRESUMEN
BACKGROUND: Asthma is a heterogeneous disease and development of novel therapeutics requires an understanding of pathophysiologic phenotypes. The purpose of the ADEPT study was to correlate clinical features and biomarkers with molecular characteristics, by profiling asthma (NCT01274507). This report presents for the first time the study design, and characteristics of the recruited subjects. METHODS: Patients with a range of asthma severity and healthy non-atopic controls were enrolled. The asthmatic subjects were followed for 12 months. Assessments included history, patient questionnaires, spirometry, airway hyper-responsiveness to methacholine, fractional exhaled nitric oxide (FENO), and biomarkers measured in induced sputum, blood, and bronchoscopy samples. All subjects underwent sputum induction and 30 subjects/cohort had bronchoscopy. RESULTS: Mild (n = 52), moderate (n = 55), severe (n = 51) asthma cohorts and 30 healthy controls were enrolled from North America and Western Europe. Airflow obstruction, bronchodilator response and airways hyperresponsiveness increased with asthma severity, and severe asthma subjects had reduced forced vital capacity. Asthma control questionnaire-7 (ACQ7) scores worsened with asthma severity. In the asthmatics, mean values for all clinical and biomarker characteristics were stable over 12 months although individual variability was evident. FENO and blood eosinophils did not differ by asthma severity. Induced sputum eosinophils but not neutrophils were lower in mild compared to the moderate and severe asthma cohorts. CONCLUSIONS: The ADEPT study successfully enrolled asthmatics across a spectrum of severity and non-atopic controls. Clinical characteristics were related to asthma severity and in general asthma characteristics e.g. lung function, were stable over 12 months. Use of the ADEPT data should prove useful in defining biological phenotypes to facilitate personalized therapeutic approaches.
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Antiasmáticos/uso terapéutico , Asma/diagnóstico , Asma/tratamiento farmacológico , Broncodilatadores/uso terapéutico , Pulmón/efectos de los fármacos , Medicina de Precisión , Adolescente , Adulto , Anciano , Asma/epidemiología , Asma/metabolismo , Asma/fisiopatología , Biomarcadores/metabolismo , Broncoconstricción/efectos de los fármacos , Canadá/epidemiología , Estudios de Casos y Controles , Europa (Continente)/epidemiología , Femenino , Humanos , Estudios Longitudinales , Pulmón/metabolismo , Pulmón/fisiopatología , Masculino , Persona de Mediana Edad , Selección de Paciente , Fenotipo , Valor Predictivo de las Pruebas , Prevalencia , Proyectos de Investigación , Pruebas de Función Respiratoria , Factores de Riesgo , Índice de Severidad de la Enfermedad , Esputo/metabolismo , Encuestas y Cuestionarios , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos/epidemiología , Adulto JovenRESUMEN
Nitric oxide (NO) is both a gas and a ubiquitous inter- and intracellular messenger with numerous physiological functions. As its synthesis is markedly increased during inflammatory processes, NO can be used as a surrogate marker of acute and/or chronic inflammation. It is possible to quantify fractional concentration of NO in exhaled breath (FENO) to detect airway inflammation, and thus improve the diagnosis of asthma by better characterizing asthmatic patients with eosinophilic bronchial inflammation, and eventually improve the management of targeted asthmatic patients. FENO measurement can therefore be viewed as a new, reproducible and easy to perform pulmonary function test. Measuring FENO is the only non-invasive pulmonary function test allowing (1) detecting, (2) quantifying and (3) monitoring changes in inflammatory processes during the course of various respiratory disorders, including corticosensitive asthma.
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Asma/diagnóstico , Espiración/fisiología , Inflamación/diagnóstico , Óxido Nítrico/análisis , Óxido Nítrico/metabolismo , Corticoesteroides/farmacología , Asma/metabolismo , Pruebas Respiratorias/instrumentación , Pruebas Respiratorias/métodos , Espiración/efectos de los fármacos , Humanos , Inflamación/metabolismo , Monitoreo Fisiológico/instrumentación , Monitoreo Fisiológico/métodos , Cooperación del Paciente , Valor Predictivo de las Pruebas , Enfermedades Respiratorias/diagnóstico , Enfermedades Respiratorias/metabolismoRESUMEN
Bronchial thermoplasty is a recent endoscopic technique for the treatment of severe asthma. It is an innovative treatment whose clinical efficacy and safety are beginning to be better understood. Since this is a device-based treatment, the evaluation procedure of risks and benefits is different that for pharmaceutical products; safety aspects, regulatory requirements, study design and the assessment of the magnitude of effects may all be different. The mechanism of action and optimal patient selection need to be assessed further in rigorous clinical and scientific studies. This technique is in harmony with the development of personalised medicine in the 21st century. It should be developed further in response to the numerous challenges and needs not yet met in the management of severe asthma.
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Asma/cirugía , Bronquios/cirugía , Broncoscopía/métodos , Electrocoagulación/métodos , Adolescente , Adulto , Anciano , Asma/epidemiología , Broncoscopía/efectos adversos , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Electrocoagulación/efectos adversos , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Índice de Severidad de la Enfermedad , Adulto JovenRESUMEN
We report the case of a 49-years-old patient who presented to the accident and emergency department with sudden onset dyspnea associated with acute shoulder pain. He was breathless at rest with supine hypoxemia. He had an amyotrophic left shoulder with localized paresis of the shoulder. Both hemi-diaphragms were elevated on chest X-rays. Pulmonary function tests showed a restrictive pattern and both phrenic nerve conduction velocities were decreased. At night, alveolar hypoventilation was evidenced by elevated mean capnography (PtcCO2: 57mmHg). Neuralgic amyotrophy, Parsonage-Turner syndrome was the final diagnosis. This syndrome is a brachial plexus neuritis with a predilection for the suprascapular and axillary nerves. Phrenic nerve involvement is rare but where present can be the most prominent clinical feature as in our case report.
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Neuritis del Plexo Braquial/complicaciones , Diafragma/patología , Parálisis Respiratoria/etiología , Neuritis del Plexo Braquial/patología , Neuritis del Plexo Braquial/fisiopatología , Diafragma/fisiopatología , Electromiografía , Humanos , Masculino , Persona de Mediana Edad , Nervio Frénico/fisiopatología , Parálisis Respiratoria/patología , Parálisis Respiratoria/fisiopatologíaRESUMEN
BACKGROUND: Although asthma is characterized by variable airways obstruction, most studies of asthma phenotypes are cross-sectional. The stability of phenotypes defined either by biomarkers or by physiological variables was assessed by repeated measures over 1 year in the Pan-European BIOAIR cohort of adult asthmatics. METHODS: A total of 169 patients, 93 with severe asthma (SA) and 76 with mild-to-moderate asthma (MA), were examined at six or more visits during 1 year. Asthma phenotype clusters were defined by physiological variables (lung function, reversibility and age of onset of the disease) or by biomarkers (eosinophils and neutrophils in induced sputum). RESULTS: After 1 year of follow-up, the allocation to clusters was changed in 23.6% of all asthma patients when defined by physiological phenotypes and, remarkably, in 42.3% of the patients when stratified according to sputum cellularity (P = 0.034). In the SA cohort, 30% and 48.6% of the patients changed allocation according to physiological and biomarker clustering, respectively. Variability of phenotypes was not influenced by change in oral or inhaled corticosteroid dose, nor by the number of exacerbations. Lower stability of single and repeated measure was found for all evaluated biomarkers (eosinophils, neutrophils and FeNO) in contrast to good stability of physiological variables (FEV1 ), quality of life and asthma control. CONCLUSION: Phenotypes determined by biomarkers are less stable than those defined by physiological variables, especially in severe asthmatics. The data also imply that definition of asthma phenotypes is improved by repeated measures to account for fluctuations in lung function, biomarkers and asthma control.