Gingival crevicular fluid levels of neopterin in healthy subjects and in patients with different periodontal diseases

Background: Neopterin, a metabolite of guanosine, belongs to the class of chemical compounds known as pteridines and is an early and valuable marker of cellular immunity. Recently, it was shown to be associated with the initiation and progression of periodontal disease. The aim of the present study was to assess the relationship between clinical parameters and concentrations of neopterin within gingival crevicular fluid (GCF) from inflamed gingiva and periodontitis sites before and after the treatment of periodontitis. Methods: Sixty age (35 to 65 years)- and gender-matched (30 males and 30 females) subjects were recruited and divided into the following four groups of 15 subjects each based on gingival index, Ramfjord periodontal disease index, clinical attachment loss (CAL), and radiographic parameters (bone loss): healthy (group 1), gingivitis (group 2), mild periodontitis (group 3), and moderate to severe periodontitis (group 4). A fifth group consisted of the 15 subjects from group 4, 6 to 8 weeks after treatment (scaling and root planing). GCF was collected from each patient, and the neopterin levels were determined by enzyme immunoassay. Results were analyzed statistically. Results: The mean concentration of neopterin in GCF was the highest in group 4 (51 nmol/l) and the lowest in group 1 (1.36 nmol/l). The mean neopterin concentrations in group 2 (9.69 nmol/l) and group 3 (16.58 nmol/l) fell between the highest and lowest values. This suggested a positive correlation between CAL and GCF neopterin concentrations. Neopterin levels in group 4 decreased to 1.77 nmol/l after treatment (group 5). Conclusions: Neopterin increased in parallel with the severity of inflammatory disease. Its levels in GCF may be potentially useful as an indicator of periodontal inflammation and the host response.