RESUMO
Concerns have been raised over the association between bisphosphonates and atypical fractures in subtrochanteric and femoral shaft regions, but the potential risk of these fractures due to bisphosphonate use in asthma has not been examined. INTRODUCTION: Bisphosphonates are used as first-line treatment for osteoporosis; however, concerns have been raised over their association with atypical subtrochanteric (ST) and femoral shaft (FS) fractures. The potential risk of atypical ST/FS fractures from bisphosphonate use in asthma has not been examined. METHODS: A nested case-control study was conducted using linked data from the Clinical Practice Research Datalink (CPRD) and Hospital Episode Statistics (HES) databases. Using an asthma cohort, we identified patients with atypical ST/FS fractures and sex, age, and practice-matched controls. Conditional logistic regression was used to determine the association between bisphosphonate exposure and atypical ST/FS fractures. RESULTS: From a cohort of 69,074 people with asthma, 67 patients with atypical ST/FS fractures and 260 matched control subjects were identified. Of the case patients, 40.3% had received bisphosphonates as compared with 14.2% of the controls corresponding to an adjusted odds ratio (aOR) of 4.42 (95%CI, 2.98 to 8.53). The duration of use influenced the risk with long-term users to be at a greater risk (> 5 years vs no exposure; aOR = 7.67; 95%CI, 1.75 to 33.91). Drug withdrawal was associated with diminished odds of atypical ST/FS fractures. CONCLUSION: Regular review of bisphosphonates should occur in patients with asthma. The risks and benefits of bisphosphonate therapy should be carefully considered in consultation with the patient. To improve AFF prevention, early signs which may warrant imaging, such as prodromal thigh pain, should be discussed.
Assuntos
Asma , Conservadores da Densidade Óssea , Fraturas do Fêmur , Fraturas do Quadril , Asma/tratamento farmacológico , Conservadores da Densidade Óssea/efeitos adversos , Estudos de Casos e Controles , Difosfonatos/efeitos adversos , Fraturas do Fêmur/induzido quimicamente , Fraturas do Fêmur/diagnóstico por imagem , Fraturas do Fêmur/tratamento farmacológico , Fraturas do Quadril/induzido quimicamente , HumanosRESUMO
The value of FENO measurements in patients with symptoms suggestive of asthma is unclear. We performed an observational study to assess the ability of FENO to diagnose asthma and to predict response to inhaled corticosteroids (ICS). Our findings suggest FENO is not useful for asthma diagnosis but is accurate at predicting ICS response.
Assuntos
Asma/diagnóstico , Testes Respiratórios/métodos , Óxido Nítrico/análise , Adolescente , Adulto , Idoso , Expiração , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Testes de Função Respiratória , Inquéritos e QuestionáriosRESUMO
Differential sputum cell counting is not widely available despite proven clinical utility in the management of asthma. We compared eosinophil counts obtained using liquid-based cytology (LBC), a routine histopathological processing method, and the current standard method. Eosinophil counts obtained using LBC were a strong predictor of sputum eosinophilia (≥3%) determined by the standard method suggesting LBC could be used in the management of asthma.
Assuntos
Asma/patologia , Escarro/citologia , Adulto , Idoso , Contagem de Células/métodos , Eosinófilos/patologia , Feminino , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Manejo de Espécimes/métodosRESUMO
BACKGROUND: Interleukin-33 (IL-33) has been subject of extensive study in the context of inflammatory disorders, particularly in asthma. Many human biological samples, including serum, have been used to determine the protein levels of IL-33, aiming to investigate its involvement in asthma. Reliable methods are required to study the association of IL-33 with disease, especially considering the complex nature of serum samples. OBJECTIVE: We evaluated four IL-33 ELISA kits, aiming to determine a robust and reproducible approach to quantifying IL-33 in human serum from asthma patients. METHODS: IL-33 levels were investigated in serum of well-defined asthma patients by the Quantikine, DuoSet (both R&D systems), ADI-900-201 (Enzo Life Sciences), and SKR038 (GenWay Biotech Inc San Diego USA) immunoassays, as well as spiking experiments were performed using recombinant IL-33 and its soluble receptor IL-1RL1-a. RESULTS: We show that 1) IL-33 is difficult to detect by ELISA in human serum, due to lack of sensitivity and specificity of currently available assays; 2) human serum interferes with IL-33 quantification, in part through IL-1RL1-a; and 3) using non-serum certified kits may lead to spurious findings. CONCLUSION AND CLINICAL RELEVANCE: If IL-33 is to be studied in the serum of asthma patients and other diseases, a more sensitive and specific assay method is required, which will be vital for further understanding and targeting of the IL-33/IL-1RL1 axis in human disease.
Assuntos
Ensaio de Imunoadsorção Enzimática , Interleucina-33/sangue , Kit de Reagentes para Diagnóstico , Asma/sangue , Asma/diagnóstico , Asma/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Ensaio de Imunoadsorção Enzimática/normas , Humanos , Kit de Reagentes para Diagnóstico/normas , Reprodutibilidade dos TestesRESUMO
Asthma attacks are a major global source of morbidity and cost. The incidence and impact of asthma attacks have not improved despite widespread adoption of effective universal treatment guidelines. Consequently, there is increasing interest in managing asthma based on specific assessments of both current symptoms and future risk. In this review, we consider 'risk' in asthma, and how it might be assessed from the patient's history and objective measurements. We also discuss the potential for encouraging shared decision-making and improving medical consensus through explicit communication of risk and highlight the potential opportunities and challenges in risk assessment to improve asthma management through individualised treatment strategies.
Assuntos
Asma/diagnóstico , Gerenciamento Clínico , Progressão da Doença , Humanos , Prognóstico , RiscoRESUMO
BACKGROUND: The effect of breathing modification techniques on asthma symptoms and objective disease control is uncertain. METHODS: A prospective, parallel group, single-blind, randomised controlled trial comparing breathing training with asthma education (to control for non-specific effects of clinician attention) was performed. Subjects with asthma with impaired health status managed in primary care were randomised to receive three sessions of either physiotherapist-supervised breathing training (n = 94) or asthma nurse-delivered asthma education (n = 89). The main outcome was Asthma Quality of Life Questionnaire (AQLQ) score, with secondary outcomes including spirometry, bronchial hyper-responsiveness, exhaled nitric oxide, induced sputum eosinophil count and Asthma Control Questionnaire (ACQ), Hospital Anxiety and Depression (HAD) and hyperventilation (Nijmegen) questionnaire scores. RESULTS: One month after the intervention there were similar improvements in AQLQ scores from baseline in both groups but at 6 months there was a significant between-group difference favouring breathing training (0.38 units, 95% CI 0.08 to 0.68). At the 6-month assessment there were significant between-group differences favouring breathing training in HAD anxiety (1.1, 95% CI 0.2 to 1.9), HAD depression (0.8, 95% CI 0.1 to 1.4) and Nijmegen (3.2, 95% CI 1.0 to 5.4) scores, with trends to improved ACQ (0.2, 95% CI 0.0 to 0.4). No significant between-group differences were seen at 1 month. Breathing training was not associated with significant changes in airways physiology, inflammation or hyper-responsiveness. CONCLUSION: Breathing training resulted in improvements in asthma-specific health status and other patient-centred measures but not in asthma pathophysiology. Such exercises may help patients whose quality of life is impaired by asthma, but they are unlikely to reduce the need for anti-inflammatory medication.
Assuntos
Asma/terapia , Exercícios Respiratórios , Adulto , Idoso , Broncoconstritores , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Hiperventilação/etiologia , Masculino , Cloreto de Metacolina , Pessoa de Meia-Idade , Óxido Nítrico/análise , Qualidade de Vida , Método Simples-Cego , Escarro/citologia , Resultado do TratamentoRESUMO
Gastro-oesophageal reflux disease (GORD) has long been associated with poor asthma control without an established cause-effect relationship. 610 asthmatics (421 severe/88 mild-moderate) and 101 healthy controls were assessed clinically and a subset of 154 severe asthmatics underwent proteomic analysis of induced sputum using untargeted mass spectrometry, LC-IMS-MSE. Univariate and multiple logistic regression analyses (MLR) were conducted to identify proteins associated with GORD in this cohort. When compared to mild/moderate asthmatics and healthy individuals, respectively, GORD was three- and ten-fold more prevalent in severe asthmatics and was associated with increased asthma symptoms and oral corticosteroid use, poorer quality of life, depression/anxiety, obesity and symptoms of sino-nasal disease. Comparison of sputum proteomes in severe asthmatics with and without active GORD showed five differentially abundant proteins with described roles in anti-microbial defences, systemic inflammation and epithelial integrity. Three of these were associated with active GORD by multiple linear regression analysis: Ig lambda variable 1-47 (pâ¯=â¯0·017) and plasma protease C1 inhibitor (pâ¯=â¯0·043), both in lower concentrations, and lipocalin-1 (pâ¯=â¯0·034) in higher concentrations in active GORD. This study provides evidence which suggests that reflux can cause subtle perturbation of proteins detectable in the airways lining fluid and that severe asthmatics with GORD may represent a distinct phenotype of asthma.
Assuntos
Asma/complicações , Asma/metabolismo , Refluxo Gastroesofágico/complicações , Proteômica/métodos , Escarro/metabolismo , Adulto , Asma/epidemiologia , Asma/psicologia , Endopeptidases/metabolismo , União Europeia/organização & administração , Feminino , Refluxo Gastroesofágico/diagnóstico , Refluxo Gastroesofágico/epidemiologia , Humanos , Cadeias lambda de Imunoglobulina/metabolismo , Lipocalina 1/metabolismo , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Inibidores de Proteases/metabolismo , Qualidade de Vida , Índice de Gravidade de DoençaRESUMO
BACKGROUND: Peroxisome proliferator-activated receptor gamma (PPAR-γ) is a nuclear receptor that modulates inflammation in models of asthma. To determine whether pioglitazone improves measures of asthma control and airway inflammation, we performed a single-center randomized, double-blind, placebo-controlled, parallel-group trial. METHODS: Sixty-eight participants with mild asthma were randomized to 12 weeks pioglitazone (30 mg for 4 weeks, then 45 mg for 8 weeks) or placebo. The primary outcome was the adjusted mean forced expiratory volume in one second (FEV1) at 12 weeks. The secondary outcomes were mean peak expiratory flow (PEF), scores on the Juniper Asthma Control Questionnaire (ACQ) and Asthma Quality of Life Questionnaire (AQLQ), fractional exhaled nitric oxide (FeNO), bronchial hyperresponsiveness (PD20), induced sputum counts, and sputum supernatant interferon gamma-inducible protein-10 (IP-10), vascular endothelial growth factor (VEGF), monocyte chemotactic protein-1 (MCP-1), and eosinophil cationic protein (ECP) levels. Study recruitment was closed early after considering the European Medicines Agency's reports of a potential increased risk of bladder cancer with pioglitazone treatment. Fifty-five cases were included in the full analysis (FA) and 52 in the per-protocol (PP) analysis. RESULTS: There was no difference in the adjusted FEV1 at 12 weeks (-0.014 L, 95% confidence interval [CI] -0.15 to 0.12, p = 0.84) or in any of the secondary outcomes in the FA. The PP analysis replicated the FA, with the exception of a lower evening PEF in the pioglitazone group (-21 L/min, 95% CI -39 to -4, p = 0.02). CONCLUSIONS: We found no evidence that treatment with 12 weeks of pioglitazone improved asthma control or airway inflammation in mild asthma. TRIAL REGISTRATION: ClinicalTrials.gov NCT01134835.
Assuntos
Asma/tratamento farmacológico , PPAR gama/agonistas , Tiazolidinedionas/uso terapêutico , Adulto , Idoso , Asma/metabolismo , Asma/fisiopatologia , Quimiocina CCL2/análise , Quimiocina CXCL10/análise , Método Duplo-Cego , Proteína Catiônica de Eosinófilo/análise , Feminino , Humanos , Hipoglicemiantes/uso terapêutico , Masculino , Pessoa de Meia-Idade , PPAR gama/metabolismo , Pioglitazona , Pneumonia/tratamento farmacológico , Pneumonia/metabolismo , Pneumonia/fisiopatologia , Qualidade de Vida , Testes de Função Respiratória/métodos , Escarro/metabolismo , Inquéritos e Questionários , Fatores de Tempo , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/análise , Adulto JovemRESUMO
The ribosomes of Entamoeba invadens trophozoites have sedimentation coefficients of 77, 53 and 36 S. Most of the ribosomal proteins are basic and their one- and two-dimensional electrophoretic patterns differ from the corresponding patterns of Escherichia coli and Saccharomyces cerevisiae. Two dozen bands were observed in the 10 000 to 100 000 molecular weight range following sodium dodecylsulfate-gel electrophoresis of amoebal ribosomal proteins. Long, thin pronase-sensitive structures were seen in electron micrographs of E. invadens ribosomal preparations.
Assuntos
Entamoeba/ultraestrutura , Ribossomos/ultraestrutura , Animais , Proteínas de Bactérias/metabolismo , Eletroforese em Gel de Poliacrilamida , Escherichia coli/metabolismo , Proteínas/metabolismo , Saccharomyces cerevisiae/metabolismoRESUMO
Nursery illumination has been implicated in the pathogenesis of retinopathy of prematurity (ROP), although the results of recent studies are conflicting. The data base for this article is a prospective ROP study on 607 infants of birth weight less than or equal to 1700 g including 35 larger siblings from multiple births when 1 infant fulfilled the birth weight criteria. Retinopathy commences preferentially in the nasal retina of the most immature neonate and is less likely to develop, or its onset is delayed, in the superior and inferior regions. These findings cannot be fully accounted for by regional vascular and neuroanatomical variations. Radiometric and physiological evidence suggests that the very immature neonate, most at risk of developing severe ROP, receives the greatest retinal irradiance. Furthermore, ROP commences in the areas of the retina receiving the highest light dose, and its onset is either retarded or inhibited in the darker retinal regions. Further studies are required to determine whether early exposure to light is a factor in the development of ROP. If a causal relationship is proven, here at least is one modality that can easily and immediately be controlled.
Assuntos
Luz , Retina/patologia , Retinopatia da Prematuridade/etiologia , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Prematuro , Luz/efeitos adversos , Masculino , Estudos Prospectivos , Retinopatia da Prematuridade/patologia , Retinopatia da Prematuridade/fisiopatologia , Fatores de TempoRESUMO
The use of topical indomethacin in the prevention of surgically induced miosis has been documented. However, in these previous prospective trials this prostaglandin synthetase inhibitor was administered the day before surgery. With the frequency of 'day case' cataract surgery increasing, an efficient preoperative mydriatic regimen is important. In this study we considered the use of topical indomethacin as an addition to a regimen already implemented. One hundred and fourteen eyes underwent intercapsular cataract surgery, of which 64 were randomised to receive topical aqueous indomethacin one hour beforehand, and 50 eyes, which did not receive indomethacin formed the comparison group. Topical indomethacin reduced the miosis which occurs during cataract surgery whether performed under local or general anaesthesia. The operating time was shorter for eyes with less surgically induced miosis.
Assuntos
Extração de Catarata , Indometacina/uso terapêutico , Midriáticos , Cuidados Pré-Operatórios , Administração Tópica , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anestesia Geral , Anestesia Local , Humanos , Indometacina/administração & dosagem , Pessoa de Meia-Idade , Soluções Oftálmicas , Distribuição AleatóriaRESUMO
The influence of a socially acceptable dose of alcohol (mean blood alcohol level approximately 90 minutes after ingestion 69.5 mg%; SE 6.20 mg%) on the central visual field as determined by automated static perimetry was investigated in 17 female subjects (17 eyes) trained in automated perimetry (mean age 22.5 years, SE 1.29 years). Central visual field examination was undertaken on the right eye with program 30-2 (stimulus size III) of the Humphrey Field Analyser 630, using a simple cross-over placebo design. Alcohol produced a small (1.0 dB) but statistically significant decrease in the mean deviation (P = 0.002) and small increases (0.6 dB) in the pattern and corrected pattern standard deviations (P = 0.003 and P = 0.046, respectively). The number of stimulus presentations increased by 6% (P = 0.006) and the number of false-negative responses also increased (P = 0.019), indicating impaired patient response. Attenuation of sensitivity as a result of alcohol increased with the increase in eccentricity (P = 0.046) independently of the meridian (P = 0.068) from a mean of 0.8 dB at 3 degrees eccentricity to 1.84 dB at 27 degrees.
Assuntos
Consumo de Bebidas Alcoólicas/efeitos adversos , Campos Visuais/efeitos dos fármacos , Adulto , Análise de Variância , Etanol/efeitos adversos , Etanol/sangue , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Luz , Reconhecimento Visual de Modelos/efeitos dos fármacos , Testes de Campo VisualRESUMO
Severe, acute and sometimes fatal intravascular haemolysis has occurred on several occasions in Papua New Guinea families after the ingestion of apparently 'stale' sago. Earlier cases had been recorded only from the Maprik area; however, we now report the occurrence of two similar outbreaks, involving a total of 14 persons, in the Western Province. Several bacteria and fungi were isolated and identified in a sample of suspect sago from one of the outbreaks. None of these, however, to our knowledge, has ever been incriminated as a cause of haemolysis, and the aetiological agent(s) and mechanism of haemolysis thus remain to be elucidated. No mycotoxins were detected in one sample available for analysis. It is suggested that the eating of sago stored for a long time be discouraged; and further that, if a meal of sago tastes abnormal, additional mouthfuls should not be eaten and the remaining portion should be sent for analysis or discarded.
Assuntos
Anemia Hemolítica/microbiologia , Microbiologia de Alimentos , Adolescente , Adulto , Anemia Hemolítica/epidemiologia , Bacillus/isolamento & purificação , Basidiomycota/isolamento & purificação , Candida/isolamento & purificação , Pré-Escolar , Feminino , Humanos , Masculino , Fungos Mitospóricos/isolamento & purificação , Micotoxinas/isolamento & purificação , Nova GuinéRESUMO
Analysis of breath acetone could be useful in the Intensive Care Unit (ICU) setting to monitor evidence of starvation and metabolic stress. The aims of this study were to examine the relationship between acetone concentrations in breath and blood in critical illness, to explore any changes in breath acetone concentration over time and correlate these with clinical features. Consecutive patients, ventilated on controlled modes in a mixed ICU, with stress hyperglycaemia requiring insulin therapy and/or new pulmonary infiltrates on chest radiograph were recruited. Once daily, triplicate end-tidal breath samples were collected and analysed off-line by selected ion flow tube mass spectrometry (SIFT-MS). Thirty-two patients were recruited (20 males), median age 61.5 years (range 26-85 years). The median breath acetone concentration of all samples was 853 ppb (range 162-11 375 ppb) collected over a median of 3 days (range 1-8). There was a trend towards a reduction in breath acetone concentration over time. Relationships were seen between breath acetone and arterial acetone (rs = 0.64, p < 0.0001) and arterial beta-hydroxybutyrate (rs = 0.52, p < 0.0001) concentrations. Changes in breath acetone concentration over time corresponded to changes in arterial acetone concentration. Some patients remained ketotic despite insulin therapy and normal arterial glucose concentrations. This is the first study to look at breath acetone concentration in ICU patients for up to 8 days. Breath acetone concentration may be used as a surrogate for arterial acetone concentration, which may in future have a role in the modulation of insulin and feeding in critical illness.
Assuntos
Acetona/análise , Estado Terminal , Hiperglicemia/diagnóstico , Espectrometria de Massas/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/análise , Testes Respiratórios/instrumentação , Desenho de Equipamento , Expiração , Feminino , Humanos , Hiperglicemia/metabolismo , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos TestesAssuntos
Proteínas de Bactérias/análise , L-Lactato Desidrogenase/análise , Acrilamidas , Animais , Isótopos de Carbono , Centrifugação com Gradiente de Concentração , Eletroforese em Gel de Poliacrilamida , Escherichia coli/análise , Escherichia coli/citologia , Géis , Humanos , Concentração de Íons de Hidrogênio , Focalização Isoelétrica , Métodos , Músculos/enzimologia , Ribossomos/análise , Especificidade da Espécie , Espectrofotometria Ultravioleta , UreiaAssuntos
Anemia Hemolítica/etiologia , Alimentos/efeitos adversos , Doença Aguda , Adolescente , Adulto , Criança , Pré-Escolar , Análise de Alimentos , Humanos , Masculino , Nova GuinéRESUMO
Tetrathiomolybdate (choline salt; ATN-224), a specific, high-affinity copper binder, is currently being evaluated in several phase II cancer trials. ATN-224 inhibits CuZn superoxide dismutase 1 (SOD1) leading to antiangiogenic and antitumour effects. The pharmacodynamics of tetrathiomolybdate has been followed by tracking ceruloplasmin (Cp), a biomarker for systemic copper. However, at least in mice, the inhibition of angiogenesis occurs before a measurable decrease in systemic copper is observed. Thus, the identification and characterisation of other biomarkers to follow the activity of ATN-224 in the clinic is of great interest. Here, we present the preclinical evaluation of two potential biomarkers for the activity of ATN-224: (i) SOD activity measurements in blood cells in mice and (ii) levels of endothelial progenitor cells (EPCs) in bonnet macaques treated with ATN-224. The superoxide dismutase activity in blood cells in mice is rapidly inhibited by ATN-224 treatment at doses at which angiogenesis is maximally inhibited. Furthermore, ATN-224 dosing in bonnet macaques causes a profound and reversible decrease in EPCs without significant toxicity. Thus, both SOD activity measurements and levels of EPCs may be useful biomarkers of the antiangiogenic activity of ATN-224 to be used in its clinical development.
Assuntos
Inibidores da Angiogênese/farmacologia , Biomarcadores/metabolismo , Endotélio Vascular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Molibdênio/farmacologia , Superóxido Dismutase/antagonistas & inibidores , Animais , Células Sanguíneas/efeitos dos fármacos , Células Sanguíneas/metabolismo , Colágeno/metabolismo , Cobre/metabolismo , Combinação de Medicamentos , Feminino , Laminina/metabolismo , Macaca radiata , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteoglicanas/metabolismo , Células-Tronco/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1RESUMO
To evaluate the toxicity, pharmacological and biological properties of ATN-161, a five -amino-acid peptide derived from the synergy region of fibronectin, adult patients with advanced solid tumours were enrolled in eight sequential dose cohorts (0.1-16 mg kg(-1)), receiving ATN-161 administered as a 10-min infusion thrice weekly. Pharmacokinetic sampling of blood and urine over 7 h was performed on Day 1. Twenty-six patients received from 1 to 14 4-week cycles of treatment. The total number of cycles administered to all patients was 86, without dose-limiting toxicities. At dose levels above 0.5 mg kg(-1), mean total clearance and volume of distribution showed dose-independent pharmacokinetics (PKs). At 8.0 and 16.0 mg kg(-1), clearance of ATN-161 was reduced, suggesting saturable PKs. Dose escalation was halted at 16 mg kg(-1) when drug exposure (area under the curve) exceeded that associated with efficacy in animal models. There were no objective responses. Six patients received more than four cycles of treatment (>112 days). Three patients received 10 or more cycles (> or =280 days). ATN-161 was well tolerated at all dose levels. Approximately, 1/3 of the patients in the study manifested prolonged stable disease. These findings suggest that ATN-161 should be investigated further as an antiangiogenic and antimetastatic cancer agent alone or with chemotherapy.
Assuntos
Inibidores da Angiogênese/toxicidade , Neoplasias/tratamento farmacológico , Oligopeptídeos/toxicidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/administração & dosagem , Inibidores da Angiogênese/farmacocinética , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oligopeptídeos/administração & dosagem , Oligopeptídeos/farmacocinéticaRESUMO
BACKGROUND: Assessment of eosinophilic airway inflammation may be helpful in the management of asthma. Nitric oxide (NO) has potential advantages as a tool to monitor airway inflammation although little is known about the relationship between NO and eosinophilic airway inflammation and the factors which influence it. METHODS: We set out to define the relationship between exhaled NO and the sputum eosinophil count, identify the exhaled NO concentration that best identified a sputum eosinophil count >3% and investigate the impact of several potential confounding factors in 566 consecutive patients with varying severity of asthma. Finally we examined the ability of exhaled NO concentrations measured at differing exhalation flows to identify the presence of a sputum eosinophilia. RESULTS: We found a significant positive relationship between exhaled NO and sputum eosinophil count (R(2)=0.26, P<0.001) which was best described using a non-linear model. There were no clinically important confounding factors to this model. In non-smokers an exhaled NO concentration of >8.3 p.p.b. at 250 mL/s gave 71% sensitivity and 72% specificity for identifying a sputum eosinophil count of >3%. CONCLUSIONS: This value of exhaled NO would seem to be the best for identifying significant eosinophilic airway inflammation. It is applicable to a wide range of non-smoking patients with asthma; exhalation flow does not alter the ability of exhaled NO concentration to detect a sputum eosinophilia.