Algorithm for the diagnosis of primary ciliary dysfunction

PCD: primary ciliary dysfunction; CVID: common variable immunodeficiency; nNO: nasal nitric oxide; HSVA: high-speed videomicroscopy analysis; TEM: transmission electron microscopy.
* Testing for cystic fibrosis may include sweat chloride or genetic testing; testing for CVID usually includes quantitative immunoglobulins. Refer to appropriate UpToDate topics.
¶ A low value for nNO (eg, ≤30 nL/minute) suggests PCD; exact threshold depends on technique.
Δ A bronchial brush can be used to obtain a nasal mucosal sample. If nasal sample is inadequate, bronchial mucosal brushing or biopsy can be obtained via flexible bronchoscopy instead.
◊ Extended panel genetic testing (>12 genes) is an alternative next step, if available. TEM may still be necessary if the extended panel is negative and there is a high suspicion of PCD.
§ Cell culture of mucosal cells may improve accuracy of HSVA.