Correlation of absent inner dynein arms and mucociliary clearance in a patient with Kartagener's syndrome.

Recent experimental studies have demonstrated extensive biochemical differences between the outer and inner dynein arms of cilia. The inner dynein arms are now emerging as the "prime movers" for ciliary clearance. We studied ciliary motility as evidenced by radioisotope mucociliary clearance, and the ultrastructure of respiratory cilia in a patient with Kartagener's syndrome. Cilia exhibited complete absence of only the inner dynein arms, while retaining outer arms, and mucociliary clearance was totally absent. We also studied neutrophil chemotaxis and other immunologic functions in our patient and found them to be normal. Our findings demonstrate an association between the structural abnormality of absent inner dynein arms alone and ciliary immotility in Kartagener's syndrome. The neutrophil migration abnormalities may have a different mechanism which needs further study.