PURPOSE: Establish the association of exhaled nitric oxide (NO) levels with active endobronchial involvement in patients with Wegener's granulomatosis. We hypothesize that abnormally elevated oral exhaled NO levels may indicate the presence of active endobronchial disease in patients with Wegener's, which would allow for a low cost non-invasive measurement of disease activity.
METHODS: Exhaled NO levels were measured, using the Sievers 280i Nitric Oxide Analyser, in 5 patients with Wegener's granulomatosis prior to bronchoscopy for suspected endobronchial involvement.
RESULTS: Exhaled NO levels were measured in 5 patients with Wegener's granulomatosis.(3 males, 2 females) 4/5 had active endobronchial disease at bronchoscopy. Of those with active inflammatory disease the mean oral exhaled NO level was 23 parts per billion (95%CI 12.3,33.7)The patient without active airway inflammation had a level of 55 (95%CI 33.3,76.3),p value= 0.02. The upper limit of normal for the lab is 30 parts per billion.
CONCLUSION: In this small group of patients, active endobronchial disease as diagnosed with bronchoscopy was not associated with elevated levels of oral exhaled NO.
CLINICAL IMPLICATIONS: Exhaled NO measurement does not appear to be elevated in association with active endobronchial disease in Wegener's granulomatosis. The curiously opposite observation, with lower levels associated with active disease, may be worthy of further investigation.
DISCLOSURE: Karina Keogh, No Financial Disclosure Information; No Product/Research Disclosure Information