Valor del óxido nítrico nasal en el diagnóstico de la discinesia ciliar primaria / Value of nasal nitric oxide in the diagnosis of primary ciliary dyskinesia

Objetivo: Comunicar los valores de óxido nítrico nasal (ONn) en niños con discinesia ciliar primaria (DCP) comparados con los niveles de ONn en niños sanos y en niños afectos de asma, fibrosis quística (FQ) y bronquiectasias pos infecciosas. Pacientes y métodos: Se realizó la determinación de ONn en 9 niños con DCP, 36 niños asmáticos, 31 niños con FQ, 8 niños con bronquiectasias post infecciosas y 37 niños sanos. Se compararon los valores de ONn en las diferentes patologías y se determinó la sensibilidad y la especificidad de la prueba para el diagnóstico de DCP. Resultados: Todos los niños con DCP excepto uno (ONn 348 ppb) mostraron un valor de ONn inferior a 112 ppb, siendo la media de 88 ppb (IC95% 9,6–166). En los niños sanos, la media del ONn fue de 898 ppb (IC95% 801–995), en los asmáticos 1023 ppb (IC95% 911–1137), en los niños con FQ 438 ppb (IC95% 367–508) y en los pacientes con bronquiectasias pos infecciosas de 361 ppb (IC95% 252–470). El valor medio de ONn fue significativamente inferior (p<0,05) en los niños afectos de DCP respecto a todos los demás grupos. Un punto de corte de NOn ≤112 ppb mostró una sensibilidad del 88,9% y una especificidad del 99,1% para el diagnóstico de DCP [área bajo la curva ROC 0,98 (IC95% 0,94–0,99); p<0,0001; razón de probabilidad 95,1]. Conclusiones: Un valor de ONn ≤ 112 ppb en niños es altamente sugestivo de DCP aunque un valor superior no descarta por completo la enfermedad (AU)

Objective: The aim of this study is to report nasal nitric oxide (nNO) values in children with primary ciliary dyskinesia (PCD) and to compare them with nNO values in healthy children, asthmatic children, children with cystic fibrosis and children with post infectious bronchiectasis. Patients and methods: We determined nNO values in 9 children with PCD, 36 asthmatic children, 31 children with cystic fibrosis, 8 children with post infectious bronchiectasis and 37 healthy children. We compared nNO values between these different conditions and calculated sensitivity and specificity of nNO to diagnose PCD. Results: All children with PCD - except one (nNO 348 ppb) – had nNO values below 112 ppb, mean 88 ppb (95%CI 9.6–166). The nNO mean was 898 ppb (95%CI 801-995) in healthy children, 1023 ppb (95%CI 911–1137) in asthmatic children, 438 ppb (95%CI 367–508) in cystic fibrosis children and 361 ppb (95%CI 252–470) in children with post infectious bronchiectasis. The mean concentration of nNO was lower (P<0.05) in PCD patients, compared to the other groups. The measurement of nasal NO in our study population showed, at a cut-off level of ≤112 ppb, a sensitivity of 88.9% and a specificity of 99.1% in the diagnosis of PCD [ROC 0.98 (95%CI 0.94–0.99); P<0.0001; probability ratio 95.1]. Conclusions: The measurement of nasal NO appears to be a useful tool for screening children for PCD, in which a cut-off level of ≤112 ppb suggests the disease, although nNO above 112 ppb does not exclude PCD (AU)

[Value of nasal nitric oxide in the diagnosis of primary ciliary dyskinesia]. / Valor del óxido nítrico nasal en el diagnóstico de la discinesia ciliar primaria.

OBJECTIVE: The aim of this study is to report nasal nitric oxide (nNO) values in children with primary ciliary dyskinesia (PCD) and to compare them with nNO values in healthy children, asthmatic children, children with cystic fibrosis and children with post infectious bronchiectasis. PATIENTS AND METHODS: We determined nNO values in 9 children with PCD, 36 asthmatic children, 31 children with cystic fibrosis, 8 children with post infectious bronchiectasis and 37 healthy children. We compared nNO values between these different conditions and calculated sensitivity and specificity of nNO to diagnose PCD. RESULTS: All children with PCD - except one (nNO 348 ppb) - had nNO values below 112 ppb, mean 88 ppb (95%CI 9.6-166). The nNO mean was 898 ppb (95%CI 801-995) in healthy children, 1023 ppb (95%CI 911-1137) in asthmatic children, 438 ppb (95%CI 367-508) in cystic fibrosis children and 361 ppb (95%CI 252-470) in children with post infectious bronchiectasis. The mean concentration of nNO was lower (P<0.05) in PCD patients, compared to the other groups. The measurement of nasal NO in our study population showed, at a cut-off level of < or =112 ppb, a sensitivity of 88.9% and a specificity of 99.1% in the diagnosis of PCD [ROC 0.98 (95%CI 0.94-0.99); P<0.0001; probability ratio 95.1]. CONCLUSIONS: The measurement of nasal NO appears to be a useful tool for screening children for PCD, in which a cut-off level of < or =112 ppb suggests the disease, although nNO above 112 ppb does not exclude PCD.

[Exhaled and nasal nitric oxide in normal and asthmatic children]. / Oxido nítrico exhalado y nasal en niños normales y asmáticos.

OBJECTIVE: Our aim was to study the concentration of nitric oxide in the exhaled (ENO) and nasal (NNO) air of normal children and asthmatic children who are clinically and functionally stable. PATIENTS AND METHODS: Using a nitric oxide chemiluminescence analyze and a register for CO2, pressure and flow, we studied 73 schoolchildren (6-17 years of age). This included 37 controls and 36 asthmatic children, 21 with mild asthma without antiinflammatory treatment and 15 treated with inhaled corticosteroids. We used the technique of slow exhalation against resistance for (ENO) determination and aspiration with stable flow in nasal cavity while holding the breath for (NNO) determination. RESULTS: The mean ENO was 3.1 ppb (1-6) in the control group, 8.3 ppb (1.7-29.3) in the mild asthma group and 7.7 ppb (2-18.3) in the asthmatics treated with corticosteroids. There were significant differences (p = 0.0001) between the controls and both asthmatic groups. The mean NNO in the controls was 898 ppb and differences between this group and the asthmatic children were found. The ENO and NNO did not change in relation to age or sex. We did not find any relationship between ENO and lung function. There is a significant correlation between ENO and NNO in both asthmatic groups, but not in the control group. CONCLUSIONS: The ENO was higher in asthmatics than in control children. The slow exhalation against resistance technique prevents the contamination of exhaled air with nasal air and this technique can be applied to children over 6 years of age. The NNO was similar in the asthmatic groups and the control group.

[Assessment of 2 portable peak expiratory flow meters and reference values for students 6 to 16 years of age]. / Evaluación de dos medidores portátiles de flujo espiratorio máximo y valores de referencia para escolares de 6 a 16 años.

OBJECTIVE: This study examines the technical characteristics of two different peak expiratory flow meters, of high range, and the reference values of peak expiratory flow (PEF) for schoolchildren. PATIENTS AND METHODS: The gauge accuracy and precision were previously determined in 20 units of each model (PF-Control and Mini-Wright), with a syringe servocontrolled by simulating 4 predetermined PEF fluxes (125, 262, 424 and 587 L/min). Relatives were asked about passive smoking and the childhood background concerning asthma, recurrent bronchitis or recent respiratory infection. The PEF of 1,142 schoolchildren, 669 boys and 473 girls between 6 and 16 years of age and coming from 6 different locations of different demographic and social characteristic of Catalonia, Spain, were measured. RESULTS: Readings of both gauges differed in accuracy, although they presented a good intradevice precision. The PF-control is within the reliance intervals for fluxes of 425 and 587 L/min, with a suprareading of 15.3% for the 262 L/min and infrareading of 19.2% for the 125 L/min controls. Flux with the Mini-Wright shows systematic over-reading of between 17.9% and 30.2%, with an accurate reading only in the 587 L/min control flux. No significant correlation was found between the PEF and family passive smoking (56.3%), pupils with asthma background (7.1%), recurrent bronchitis (11%) or recent respiratory infection (7.7%). CONCLUSIONS: The accuracy difference forces the use of diverse percentile tables for each of the PEF gauge patterns; hence, we present the reference tables for each gauge, in means of 10, 50 and 90 percentiles, which can be used as reference values for our school population according to their age, size and sex.