This will be an observational study. Participants who are referred by their clinician for nasal NO testing and meet the inclusion and exclusion criteria will be allowed to undergo testing. Informed consent will be completed prior to testing. The participant and/or guardian will be informed that this testing is not a clinically approved test at this time and thus it cannot confirm diagnosis of PCD. This test is to correlate with other diagnostic tests so that in the future it can be an approved diagnostic test. Data will be collected from the electronic medical records regarding participants.~The data collected will be stored on a REDCap (Research Electronic Data Capture) registry. The registry will contain participants' direct identifiers (like medical record). De-identified data will be used from the registry for monitoring, further analysis and presentations. The results of the testing may be included in the medical chart of each participant as part of the diagnosis discussion with family.~Consent forms will be obtained from participants >18 years of age or who are emancipated minors, or guardian for patients <18 years of age. Guardian refers to parent, guardian, or legally authorized personnel throughout this document.~The data collected will be used to refine and improve the diagnostic testing for PCD at Arkansas Children's Hospital. This will also involve collaboration with other sub-specialties like otolaryngology and allergy/immunology. With continued research regarding nasal nitric oxide testing, this may involve the use of this test as a screening tool for PCD in the right clinical setting. This will involve analyzing the association of nasal nitric oxide levels with approved diagnostic tests (ciliary biopsy and genetic testing).~Testing will be completed using (Eco-Physics Analyzer CLD 88 sp with DENOX 88). this testing will be done in the Arkansas Children's hospital pulmonary function laboratory, once all training is completed.~This equipment is not currently FDA approved for PCD diagnostic testing and therefore, referring clinicians will be informed of the results of this test and its limitations as a research tool will be discussed. However, there is growing evidence that this testing has utility as a non-invasive screening tool for PCD and continued data from the general pediatric pulmonary population is needed.~In addition to being non-invasive testing, it has very little risk as it simply monitors nasal nitric oxide levels in the sinus cavities during regular breathing without sedation. There is ongoing research to better determine normative values and thresholds for further PCD confirmatory testing, especially in the younger population. In the general population this testing has a greater negative predictive value than a positive predictive value. Consequently, the testing will be done on individuals who have at least two of the following clinical criteria for PCD: history of neonatal respiratory distress, chronic rhinitis, chronic cough, or situs defects.
this study is aiming at learning more about primary ciliary dyskinesia (PCD) and tests that are used to diagnose this condition. One purpose of this study is to measure the level of nitric oxide in the nasal passages and examine how often the results correlate with other tests currently done to make the diagnosis.