Nasal cytology in children: scraping or swabbing?

Nasal cytology has become a valuable tool in the assessment of a multitude of nasal pathologies in children. Collection methods differ significantly and even though the use of the nasal curette is regarded as the most reliable in adults, most practitioners use the nasal swab in children. However, no studies have validated the reliability and supposed better tolerability of the latter. We have compared these two sampling methods regarding their tolerability and analysed the diagnostic accuracy of the cotton nasal swab (NSW) to identify nasal cytotypes and rhinitis phenotypes, using nasal scraping (NSC) for comparison. In a multicentric prospective study we recruited 208 children and performed nasal cytology by means of NSW and NSC. Microscopic evaluating of the nasal cytotypes was performed and tolerability of NSW and NSC was tested. Our data revealed a significantly inferior diagnostic accuracy of NSW compared to NSC regarding reliability and cell counts. Our study is the first to shed light on the role of the sampling tools for pediatric nasal cytology. We documented a poor diagnostic accuracy of NSW, thus suggesting using only the nasal curette in clinical practice. Furthermore, tolerability did not differ between the two, refuting the common thesis that swabs are to be preferred when doing nasal cytology in children.