PRIMARILY NASAL ORIGIN OF EXHALED NITRIC-OXIDE AND ABSENCE IN KARTAGENERS-SYNDROME

The exact origin of nitric oxide (NO) in exhaled air is not known. We wanted to further investigate at what site exhaled NO is produced and to determine whether children with Kartagener's syndrome exhibited alt ered levels of exhaled NO. NO was measured by chemiluminescence techni que in air sampled directly from the nose and in normally exhaled air of four children (2.5-13 years old) with Kartagener's syndrome, 20 hea lthy children, four healthy adults, and four conscious tracheostomized adults. NO was almost absent (98% reduced) in air sampled directly fr om the nose in four children with Kartagener's syndrome (4+/-1 parts p er billion (ppb)), compared to age-matched controls (221+14 (ppb)). Tr acheostomized adult subjects had considerably higher NO values in nasa lly (22+/-3 ppb) and orally (14+/-2 ppb) exhaled air, compared to leve ls in air exhaled through the tracheostomy (2+/-0 ppb). Treatment with intranasal corticosteroids for 14 days, or with antibiotics for 1 wee k, did not affect exhaled NO. These results clearly show that, basical ly, all NO in exhaled air of healthy subjects originates from the uppe r respiratory tract, with only a minor contribution from the lower air ways. Furthermore, the absence of nasal NO in children with Kartagener 's syndrome could be of use as a simple noninvasive diagnostic test.