1.2 Allergy and post-viral acute rhinosinusitis and acute
bacterial rhinosinusitis (ABRS) in children.
In the articles reviewed we did not find manuscript in which authors
distinguished between post viral ARS and ABRS. Authors focused the
attention in the particular on the risks of bacterial superinfection.
Recent evidence suggests in fact that damage or disruption of
mucociliary function due to viral infection is probably a major cause of
super- or secondary bacterial infection. Allergy is a condition that
potentially can exacerbate an inflammatory sino-nasal response, although
very limited data are available to confirm this
hypothesis.(28) Based on paucity and heterogeneity of
the studies it was not possible to perform a qualitative analysis
linking allergy to ABRS or to post viral ARS(7) for
this reason we report by a narrative description available data.
Lin et al.(29) demonstrated that the prevalence of
colonization by methicillin-resistant S. aureus was higher in atopic
children than healthy ones and that atopic children were more likely to
develop ARS than nonatopic ones. Interestingly, other authors(30) observed that AR was highly prevalent in orbital
ARS complications in children and, specifically, it was found in 64.3%
of children with pre-septal cellulitis, in 25% with periostitis, and in
76.5% with subperiosteal abscess. Furthermore, the prevalence of AR was
significantly higher in patients presenting in pollen season from
February to August than in patients presenting between September and
January. The authors suggested that allergy may be a cofactor in the
pathogenesis of orbital complication of ARS. In addition, Alho et al.(31) observed that subjects with allergic IgE-mediated
rhinitis had more severe paranasal sinus changes in CT scans than
non-allergic subjects during viral colds. The authors suggested that
these changes were signs of more severely impaired sinus function,
increasing the risk of bacterial sinusitis.
Shi-Wei
Lin et al.(32) recently evaluated the risk of
incident acute rhinosinusitis among children with allergic rhinitis,
using a nationwide, population-based health claims research database and
including a large number of patients. The authors observed that the risk
of acute rhinosinusitis was significantly higher in pediatric patients
with allergic rhinitis compared to those without the condition (adjusted
hazard ratio = 3.03, 95% confidence interval = 2.89–3.18). Caution is
advised when interpreting the findings of the authors due to limitations
of the study: retrospective design, diagnosis of ARS based on clinical
history (authors could not confirm bacterial etiology of sinusitis).
On the other hand, Leo et al.(33) demonstrated that
children with grass pollen induced rhinitis during exposure to pollen
had an incidence of endoscopically confirmed ARS comparable to
non-allergic children; they consequently suggested that AR was a
negligible risk factor for ARS and that the most common risk factor was
instead a previous acute viral infection. Accordingly, EPOS 2020
concluded that there appears to be small evidence to support the
presence of AR as a risk factor for developing ARS in children,
recognizing a central role for previous viral infection.