Salivary Biomarker Concentrations in Patients with Intraoral Lesions and Controls

Objectives: The quantification of salivary biomarkers may aid with diagnosis and monitoring of oral disease. This study aims to compare the concentrations of six inflammatory mediators (IL-1b, IL-4, IL-6, IL-8, TNF-alpha, and CRP) in the saliva of patients with inflammatory intraoral lesions (cases) versus healthy subjects (controls). Methods: Case subjects had ≥ 1 intraoral lesion producing inflammation of the surrounding tissues, while controls had no clinical signs of intraoral inflammation. Saliva samples were collected from 25 cases (72% female, mean age 49.5±18.6) and 25 age- and sex-matched controls (72% female, mean age 46.0±15.5) via passive expectoration. Lesion diagnoses were recorded, and saliva samples underwent ELISA to determine biomarker concentrations. Descriptive and comparative statistics using Analysis of variance (ANOVA) were performed with SPSS 17.0 (Chicago, IL). Results: Of the 25 lesion subjects, 52% were diagnosed with lichen planus (n=13), 36% with aphthous ulcerations (n=9), and 12% with fungal infection (n=3). When comparing the lesion group to the control group, no statistically significant difference in biomarker concentrations were found for any of the six biomarkers. IL-4 concentrations were significantly higher in patients with fungal infection (10.83±16.53 ng/ml) compared to control (1.49±1.58 ng/ml) and lichen planus (1.66±1.86 ng/ml) patients (ANOVA, p=.032 and .049, respectively). IL-6 concentrations were higher in patients with chronic inflammatory lesions (17.69±26.76 ng/ml) compared to controls (5.11±13.08 ng/ml), but this difference was not statistically significant (ANOVA, p=.079). Conclusions: Our results reveal that salivary IL-4, a cytokine important in immune upregulation, is significantly elevated in patients suffering from fungal infection. IL-6 may be elevated with chronic inflammatory lesions, although this difference was not statistically significant in our study. Further investigation is required to determine if salivary cytokines and other salivary inflammatory mediators may have future potential in the diagnosis, monitoring, and/or risk assessment of acute and chronic oral inflammatory conditions.