RESUMO
The cilia are an essential component of the respiratory defense system. Certain ciliary abnormalities are produced by chronic infections. In this prospective study, ultra-structural features of cilia are described in 46 subjects. Thirty patients were studied for the problem of recurrent chest infections; of these, 6 showed ciliary abnormalities which were specific and diagnostic of primary ciliary dyskinesia. In 24 patients there were other abnormalities which were presumably secondary to chronic infections. This paper describes the various ciliary abnormalities seen in the latter group. It is emphasized that, as ciliary abnormalities may be the result rather than the cause of infections, a diagnosis of primary ciliary dyskinesia should be made with caution