Óxido nítrico exhalado e índice predictivo de asma en menores de dos años / Fraction of Exhaled Nitric Oxide and Asthma Predictive Index in Infants Less Than Two Years-Old

Introducción: La fracción exhalada del óxido nítrico (FENO) se considera marcador indirecto de la inflamacióneosinofílica de la vía aérea. En niños colaboradores la metodología habitual es mediante respiraciónúnica. La imposibilidad de realizarla en niños no colaboradores ha permitido desarrollar la técnica a respiracióncorriente on-line y off-line. El objetivo del estudio ha sido analizar la relación entre la FENO on-linea respiraciones múltiples y el índice predictivo de asma (IPA) en niños menores de dos años.Material y métodos: Estudio observacional y transversal en una muestra consecutiva de niños y niñas entredos meses y dos años de edad, durante un período de 4 meses. Se determinó la FENO postprandial onlinea respiración corriente con respiraciones múltiples y flujo espiratorio entre 40 y 60 ml/s, medianteanalizador de quimioluminiscencia estacionario (CLD 88 sp). Variables cuantitativas: edad, peso, IgE,eosinofilia, FENO, flujo espiratorio. Variables cualitativas: sexo, dermatitis atópica, rinitis alérgica, alergiaalimentaria y medicamentosa, antecedentes familiares de asma y atopia, diagnóstico y tratamiento. Seha analizado la asociación entre IPA y FENO mediante test exacto de Fisher y t de Student y el grado deacuerdo entre IPA y FENO mediante Kappa de Cohen. Se ha estudiado la relación entre eosinofilia, IgE,dermatitis atópica y FENO (test exacto de Fisher y t de Student).Resultados: Cohorte constituida por 38 pacientes. Realizaron las determinaciones con éxito 32 (84,21%)casos. Edad media 10,9±5,06 meses. Los casos con IPA positivo tenían valores de FENO significativamentesuperiores a los IPA negativos con grado de acuerdo entre IPA y FENO de 0,71.Conclusiones: Existe asociación significativa y un buen grado de acuerdo entre la FENO a respiracióncorriente online y el IPA(AU)

Introduction: The fraction of exhaled nitric oxide (FENO) is considered as an indirect marker of eosinophilicinflammation of the airway. In collaborating children the usual method is by a single breath. Theimpossibility of performing this in non-collaborating children has led to the development of the onlineand offline tidal breathing technique. The objective of the study has been to analyse the relationshipbetween the multiple breaths online FENO and the asthma predictive index (API) in children less than 2years-old.Material and methods: An observational and cross-sectional study on a consecutive sample of boys andgirls between 2 months and 2 years of age, over a period of 4 months. The post-prandial multiple breathsonline FENO and flow spirometry between 40 and 60 ml/s, using a stationary chemiluminescence analyser(CLD 88 sp). The quantitative variables were: age, weight, IgE, eosinophilia, FENO, flow spirometry. Thequalitative variables were: gender, atopic dermatitis, allergic rhinitis, food and medical allergies, familyhistory of asthma and atopy, diagnosis and treatment. The relationship between API and FENO was analysedusing the exact Fisher and Student t tests and the level of agreement between API and FENO usingCohen’s Kappa. The relationship between eosinophilia, IgE, atopic dermatitis and FENO was also studied(exact Fisher and Student t tests). Results: The cohort consisted of 38 patients. The determinations were successfully carried out on 32(84.21) of the cases. The mean age was 10.9±5.06 months. The cases with a positive API had significantlyhigher FENO values than those with a negative API, with a level of agreement between API and FENO of0.71.Conclusions: There is a significant relationship and a good level of agreement between the online tidalbreathing FENO and the API(AU)

Fraction of exhaled nitric oxide and asthma predictive index in infants less than two years-old.

INTRODUCTION: The fraction of exhaled nitric oxide (FE(NO)) is considered as an indirect marker of eosinophilic inflammation of the airway. In collaborating children the usual method is by a single breath. The impossibility of performing this in non-collaborating children has led to the development of the online and offline tidal breathing technique. The objective of the study has been to analyse the relationship between the multiple breaths online FE(NO) and the asthma predictive index (API) in children less than 2 years-old. MATERIAL AND METHODS: An observational and cross-sectional study on a consecutive sample of boys and girls between 2 months and 2 years of age, over a period of 4 months. The post-prandial multiple breaths online FE(NO) and flow spirometry between 40 and 60 ml/s, using a stationary chemiluminescence analyser (CLD 88 sp). The quantitative variables were: age, weight, IgE, eosinophilia, FE(NO), flow spirometry. The qualitative variables were: gender, atopic dermatitis, allergic rhinitis, food and medical allergies, family history of asthma and atopy, diagnosis and treatment. The relationship between API and FE(NO) was analysed using the exact Fisher and Student t tests and the level of agreement between API and FE(NO) using Cohen's Kappa. The relationship between eosinophilia, IgE, atopic dermatitis and FE(NO) was also studied (exact Fisher and Student t tests). RESULTS: The cohort consisted of 38 patients. The determinations were successfully carried out on 32 (84.21) of the cases. The mean age was 10.9±5.06 months. The cases with a positive API had significantly higher FE(NO) values than those with a negative API, with a level of agreement between API and FE(NO) of 0.71. CONCLUSIONS: There is a significant relationship and a good level of agreement between the online tidal breathing FE(NO) and the API.