Primary ciliary dyskinesia (the immotile cilia syndrome).

Objective: The purpose of this review is to familiarize the reader with the genetic aspects, clinical manifestations, diagnostic techniques and management of the primary ciliary dyskinesia syndrome. Further, this article illustrates some unusual features of this syndrome and discusses some speculative hypotheses concerning its pathogenesis and clinical presentation.

Data sources: The bibliography includes references in English as well as some references of historical interest in German. Both human and veterinary literature are quoted. Sources included computerized bibliographic searches of recent literature and reviews of literature.

Study selection: Selection of papers was made based on their historic importance in the definition and characterization of the disease, and on reviews of large bodies of novel or interesting information. Some review papers were not included to avoid repetition.

Results: Although the incidence of primary ciliary dyskinesia is low, the inclusion of this condition in the differential diagnosis of chronic and recurrent sinobronchial disease in children and older individuals is very common. Primary ciliary dyskinesia should be suspected in individuals who present chronic respiratory symptoms already in the neonatal period, develop profuse, chronic mucopurulent rhinorrhea, and chronic otitis media and sinusitis. Chronic cough, obstructive lung disease, and bronchorrhea associated with the aforementioned manifestations should also make clinicians suspect this syndrome. Male sterility is almost universally present and situs inversus is present in 50% of affected persons. The diagnosis of primary ciliary dyskinesia is clinical and is confirmed by studies of ciliary motility and ultrastructure of the respiratory mucosa. Management is directed to microbial suppression by frequent antibiotic administration, and to clearing of retained secretions.

Conclusions: The diagnosis of primary ciliary dyskinesia requires familiarity with the clinical picture and the specific techniques of identification. Although the basic mechanism of disease is known, the molecular genetics of primary ciliary dyskinesia and the causes for the phenotypic variability remain to be explained. Future research should be directed to the identification of the gene(s) responsible for the manifestations of the disease and to effective methods of activation, in vivo, of dysfunctional cilia.