Disrupted ciliated epithelium shows slower ciliary beat frequency and increased dyskinesia.

Ciliary function studies for the diagnosis of primary ciliary dyskinesia (PCD) are usually performed on nasal brush biopsy samples. It is not uncommon to find disrupted epithelial strips of tissue in these samples, and occasionally throughout a sample. The aim of the present study was to determine if cilia on disrupted ciliated epithelial edges beat with a normal pattern and frequency similar to that of cilia on undisrupted edges. Nasal brush biopsy samples from 42 children in whom the diagnosis of PCD was excluded were assessed. The epithelial strips were categorised into five groups: intact undisrupted ciliated epithelial edge, ciliated epithelial edge with minor projections, ciliated epithelial edge with major projections, an isolated ciliated cell on an epithelial edge and single unattached ciliated cells. Ciliary beat frequency and beat pattern of 50 samples from each group were determined using high speed digital video microscopy. The cilia on epithelial edges with varying degrees of disruption showed significantly reduced beat frequency and significantly increased dyskinesia compared with those on intact, undisrupted ciliated epithelial edges. Ideally, the assessment of ciliary beat pattern and frequency for PCD diagnosis should only be performed on undisrupted ciliated edges.