Nasal Nitric Oxide in Atypical Primary Ciliary Dyskinesia

Background:Atypical cases of primary ciliary dyskinesia (PCD) may present with minimal transmission electron microscopy (TEM) defects. The diagnostic role of nasal nitric oxide (nNO) levels was evaluated in those patients.Methods:Sixty-four children with recurrent pneumonia were studied with ciliary motion analysis, TEM, and nNO.Results:Investigations indicated PCD in 12 patients, secondary ciliary dyskinesia (SCD) in 50 patients, and normal results in 2 patients. In 4 of 50 children with SCD, atypical PCD was considered possible. The mean (± SD) nNO was 130 ± 46.95 parts per billion in children affected by PCD, 127.79 ± 68.58 parts per billion in atypical patients, and 760 ± 221 parts per billion in children with SCD. Three to 5 months later, the nNO level was 132.75 ± 55.76 parts per billion in children with atypical disease and 778.00 ± 197 parts per billion in children with SCD.Conclusion:Low levels of nNO may help to identify patients with atypical PCD.