Nasal brushing: a clinically useful procedure in pediatric patients with rhinosinusitis?

Sinusitis is a common complication of non-allergic and allergic rhinitis, and can trigger lower respiratory diseases, such as bronchitis and asthma. Standard radiography is unable to give any data about the underlying pathological mechanisms (infectious or allergic) involved and infectious rhinosinusitis is very common in pediatric age, even in allergic patients. We investigated the possibility of obtaining more useful diagnostic information, performing nasal brushing (NB) on 117 children with recurrent respiratory symptoms. The following hypothesis were evaluated: (1) whether NB neutrophil/eosinophil percentages and/or NB culture could predict the radiological evidence of maxillary sinusitis; and (2) whether differences between nonallergic and allergic patients could be detected. In the total patient group and in the nonallergic group, the comparison of NB neutrophil percentages in patients with and without maxillary sinusitis showed a statistically significant difference (median 2 and 18%, respectively; P < 0.001). In the nonallergic group, a NB neutrophil rate > or = 5% was chosen as a cut-off between positive and negative NB diagnosis of rhinosinusitis and NB data were compared with radiological investigations. The results obtained showed that NB was fairly sensitive (91%) and predictive (84%). In allergic patients, neither neutrophil nor eosinophil percentages significantly correlated with the presence of sinusitis. Microbiological studies showed that, even if the presence of bacteria in NB resulted associated with sinusitis, a negative culture was not predictive of the absence of the disease. We therefore suggest that NB describes the present inflammatory status of the upper airways, hence, it is more suitable to describe the inflammation related to ongoing upper respiratory tract infections rather than chronic inflammation due to allergic rhinitis, characterized by relapsing episodes of acute inflammation. In conclusion, we propose to consider NB a reliable tool in the diagnosis of rhinosinusitis, particularly in nonallergic pediatric patients. Compared to standard radiological techniques, NB makes it possible to avoid radiation exposure and gives information about the pathological mechanisms involved in the single patient.