NASAL CYTOLOGY: TOWARDS A DISCOVERING OF A PREDICTIVE TOOL OF COMMON AIRWAYS DISEASES¿ ONSET IN PEDIATRIC POPULATION

Pediatric diseases such as Acute Otitis Media (AOM), Upper Respiratory Tract Infections (URTI), bronchitis, asthma, allergy, rhinosinusitis and adenoidal hypertrophy are a daily challenge for clinicians such as otorhinolaryngologists, pediatricians and allergists. Those pathologies may lead, especially during the growth period, to relevant comorbidities and complications such as obstructive sleep apnea syndrome (OSAS), hearing impairment as well as learning and attention difficulties and it is presumable that such diseases may have important implications in both scholar and social performances1,2. The possibility to screen newborns for the risk of developing these diseases would be therefore of enormous value, in order to potentially engage in strict follow-up that could guarantee early diagnosis and hence satisfactory treatment. However, to our knowledge, it is currently difficult to determine predictive factors which may increase the risk of developing any of these clinical issues. Nowadays, family history, smoking of the parents and similar environmental factors, are the only correlations that clinicians may find and which may suggest a predisposition to some of these pathologies such as asthma or allergy. However, no objective measures have been introduced into neonatal screenings. Nasal cytology (NC) is a simple diagnostic procedure to evaluate the health of the nasal mucosa by recognizing and counting cell types and their morphology2,3. NC is able to detect infectious agents such as fungi and bacteria, allowing for example the diagnosis of infectious rhinitis. It also evaluates cellular composition detecting ciliated and muciparous cells, eosinophils, neutrophils, mast cell and other. Specific cytological patterns in NC can help in discriminating among various forms of rhinitis, including Allergic Rhinitis (AR), Non Allergic Rhinitis (NAR), idiopathic rhinitis, and overlapping forms3. Since the diagnosis of atopy and allergy in children, especially in the youngest age groups, is a difficult challenge and requires careful and broad analysis, NC may be considered a valid diagnostic tool, thanks to its simple, noninvasive and inexpensive method able to show any sign of local type 2 inflammation in the nasal mucosa4. Moreover, following the “united airways” concept, both upper and lower airways tracts share the same mucosal structure and functioning, and nasal secretions are delivered directly into the bronchial airways5. Therefore, diagnosis and treatment of nasal airways is essential to also improve and/or prevent lower respiratory tract disfunctions. Previous studies have looked at an array of rhinocytograms in neonates and infants. Assessing healthy newborns or newborns exposed to for e.g cigarette smoke6,7. However, these studies are very heterogeneous in their enrollment of subjects and leave many questions unanswered. We therefore thought to extend this concept to other common pediatric pathologies, and hence to uncover if there is a link between nasal cellular composition at birth and the chance of developing such diseases in the first 3 years of life. Literature already explored the ability of nasal cytology in predicting the onset of various diseases, but to our knowledge no longitudinal prospective studies have been performed correlating nasal cytology at birth and the later onset of any disease8. The study aims to collect and analyze the nasal mucosa cytological composition, on a bigger scale as previously reported, at birth (in the first 24 hours of life) and therefore obtaining an uncontaminated and representative sample; collection of nasal mucosa cytology at 1 and 3 years of life in order to analyze any variation on its composition. Moreover, we set a longitudinal prospective study until 3 years of life of the child in order to evaluate the association of nasal cytology with the development of diseases like asthma, rhinitis, allergy, bronchitis, otitis and URTI and to assess whether nasal cytology is influenced by selected external factors. Finally, we would like to provide a baseline of cytological composition as well as of any external influencing factors that could interfere with the nasal cell composition in order to further investigate the relationship between genetic and environmental components in the pathogenesis of these diseases, since no literature sheds light on this topic.