The role of toll-like receptor (TLR)-2 and TLR-4 in pediatric patients
with pneumonia
Abstract
Background: Since rapid and accurate diagnosis of pneumonia and
the determination of its severity are challenging, especially in
childhood, we aimed to evaluate the role of toll-like receptors (TLRs)
in pneumonia, the investigation of which has been limited in animal and
adult studies. Methods: TLR-2, TLR-4, interleukin (IL)-1β,
IL-4, IL-6, IL-10, interferon (IFN)-α, and tumor necrosis factor (TNF)-α
levels were evaluated in the serum samples of 67 pediatric patients with
community-acquired pneumonia (CAP) (43 inpatients and 24 outpatients)
and 22 healthy pediatric controls. Saliva samples from 30 pediatric
patients with CAP (19 inpatients and 11 outpatients) and 20 healthy
pediatric controls were also investigated. Results: In saliva
samples obtained at the time of diagnosis, the threshold levels were
1.16 2 -(∆∆Ct) for TLR-2 and 1.28 2
-(∆∆Ct) for TLR-4 to differentiate patients with and
without pneumonia, respectively. The sensitivity of salivary TLR-2 and
TLR-4 assessment was 0.80 and 0.86, respectively. In the serum samples,
TLR-2, TLR-4, IL-1β, IL-4, IL-6, IL-10, IFN-α, and TNF-α levels were
significantly decreased in patients with novel coronavirus disease 2019
(COVID-19) compared with other viruses (p<0.05 for all). In
the serum samples of patients with pneumonia due to COVID-19, IL-6 and
IFN-α levels were significantly lower than in the control group
(p<0.05 for all). Conclusion: Salivary analysis of
TLR-2 and TLR-4 is beneficial in the diagnosis of severe pneumonia,
especially in childhood.