Exhaled nitric oxide as a diagnostic test for asthma in rhinitic patients with asthmatic symptoms

Heffler, Enrico; Guida, Giuseppe; Marsico, Pietro; Bergia, Roberta; Bommarito, Luisa; Ferrero, Nicoletta; Nebiolo, Franco; De Stefani, Antonella; Usai, Antonio; Bucca, Caterina; Rolla, Giovanni

doi:10.1016/j.rmed.2006.02.019

« Previous Next »Respiratory Medicine
Volume 100, Issue 11 , Pages 1981-1987, November 2006

Exhaled nitric oxide as a diagnostic test for asthma in rhinitic patients with asthmatic symptoms

Enrico Heffler
- Allergologia e Immunologia Clinica, University of Torino, Ospedale Mauriziano Umberto I, Largo Turati 62, 10128 Torino, Italy
Giuseppe Guida
- Allergologia e Immunologia Clinica, University of Torino, Ospedale Mauriziano Umberto I, Largo Turati 62, 10128 Torino, Italy
Pietro Marsico
- Allergologia e Immunologia Clinica, University of Torino, Ospedale Mauriziano Umberto I, Largo Turati 62, 10128 Torino, Italy
Roberta Bergia
- Allergologia e Immunologia Clinica, University of Torino, Ospedale Mauriziano Umberto I, Largo Turati 62, 10128 Torino, Italy
Luisa Bommarito
- Allergologia e Immunologia Clinica, University of Torino, Ospedale Mauriziano Umberto I, Largo Turati 62, 10128 Torino, Italy
Nicoletta Ferrero
- Allergologia e Immunologia Clinica, University of Torino, Ospedale Mauriziano Umberto I, Largo Turati 62, 10128 Torino, Italy
Franco Nebiolo
- Allergologia e Immunologia Clinica, University of Torino, Ospedale Mauriziano Umberto I, Largo Turati 62, 10128 Torino, Italy
Antonella De Stefani
- Otorinolaringoiatria, Ospedale Mauriziano Umberto I, Largo Turati 62, 10128 Torino, Italy
Antonio Usai
- Otorinolaringoiatria, Ospedale Mauriziano Umberto I, Largo Turati 62, 10128 Torino, Italy
Caterina Bucca
- Ospedale Molinette and Dipartimento di Scienze Biomediche e Oncologia Umana, University of Torino, Via Genova 3, 10126 Torino, Italy
Giovanni Rolla
- Allergologia e Immunologia Clinica, University of Torino, Ospedale Mauriziano Umberto I, Largo Turati 62, 10128 Torino, Italy
- Corresponding author. Tel.: +39115082083; fax: +39115682588.

Received 21 November 2005; accepted 23 February 2006. published online 03 April 2006.

Summary

Background

Rhinitis is a major risk factor for asthma, so that evaluation of the lower airways is recommended in patients with rhinitis. Exhaled nitric oxide (FE_NO) is considered a marker of airway inflammation and it has been found to be useful for the screening of patients with suspected diagnosis of asthma. Our aim was to assess the validity and accuracy of FE_NO to identify patients with asthma in 48 non-smoking patients with persistent rhinitis and asthma-like symptoms.

Methods

Asthma was diagnosed on the basis of 12% improvement in FEV₁ after salbutamol or a methocholine PD₂₀FEV₁<800μg. Prior to lung function FE_NO was measured with the single exhalation method at 50ml/s.

Results

The geometric mean (95% confidence interval) FE_NO was significantly higher in the 18/48 asthmatics than in the non-asthmatic patients (60ppb, CI 95%: 50–89, versus 30ppb, CI 95%: 28–45, ). Receiver operating characteristic (ROC) curve for the diagnosis of asthma indicated that FE_NO is an acceptable discriminator between patients with and without asthma (area under the ROC curve=0.78). None of the asthmatic patients had FE_NO values<25ppb and all the patients with FE_NO>100ppb () were asthmatics. The sensitivity and specificity of FE_NO for detecting asthma, using 36ppb as cut-off point, were 78% and 60% and the positive and negative predictive values were 54% and 82%, respectively.