Salivary biomarkers in the context of gingival inflammation in children with cystic fibrosis

Background Cystic fibrosis (CF) is a life‐threatening chronic inflammatory disease in children due to respiratory complications. Saliva could serve as a reservoir of bacterial colonization and potentially reflect systemic inflammation. This study investigated whether salivary triggering receptor expressed on myeloid cells 1 (TREM‐1), peptidoglycan recognition protein 1 (PGLYRP1), interleukin (IL)‐1β, and calprotectin are associated with CF or reflect concomitant gingival inflammation. Methods Ten CF (aged 3 to 12 years) and 10 systemically healthy (SH) age‐ and sex‐matched children (C) were enrolled in the study. Individuals with CF underwent routine laboratory determinations. Probing depth, gingival index (GI), plaque index (PI), and bleeding on probing (BOP) were recorded on fully erupted teeth and saliva samples collected. Salivary TREM‐1, PGLYRP1, IL‐1β, and calprotectin were analyzed by enzyme‐linked immunosorbent assay. Results Children with CF had significantly higher BOP scores (P = 0.001) and calprotectin levels (P = 0.017) compared with the C group. TREM‐1, PGLYRP1, and IL‐1β could not distinguish between CF and SH but showed positive correlation with GI, PI, and BOP in both groups. Calprotectin levels positively correlated with procalcitonin (P = 0.014), thrombocyte counts (P = 0.001), mean platelet volume (P = 0.030), and with PGLYRP1 (P = 0.019) and IL‐1β (P = 0.013) in CF children. Receiver operating characteristic curve analysis for calprotectin (CFvsC) showed an area under the curve of 0.79 (95% CI 0.58 to 0.99, P = 0.034). Conclusions CF children presented with higher gingival inflammation scores and salivary calprotectin levels, that correlated with systemic inflammatory markers. Salivary calprotectin levels were not associated with periodontal parameters. Hence, preliminary data demonstrate that salivary calprotectin might have a chairside diagnostic potential for CF in children.