Primary ciliary dyskinesia associated with a novel microtubule defect in achild with Down's syndrome

We present a child with Down's syndrome, bilateral lower lobe bronchiectasi s, sinusitis, and severe ear disease who was found to have a novel ciliary defect, with a frequent, partial absence of the walls of the A subunits of some peripheral doublets, Time defect caused the A subunits to be "U-shaped " rather than "O-shaped". A nuclear nasal mucociliary transport study confi rmed that this defect was associated with abnormal mucociliary transport. T he ciliary defect was not observed in a biopsy performed in a second patien t who had Down's syndrome.