Comparison of simple and rapid collection methods for measuring salivary IL-6 and PGE₂ in cats with chronic...

Feline chronic gingivostomatitis (FCGS) is characterized by persistent oral inflammation, leading to severe pain, hyporexia, weight loss, and reduced well-being. Affected cats exhibit altered levels of inflammatory mediators; however, most diagnostic procedures require administration of anesthesia, highlighting the need for alternative monitoring approaches. This prospective exploratory pilot study aimed to compare two simple and rapid saliva collection methods-pipetting and absorbent paper points-used for assessing prostaglandin E₂ (PGE₂) and interleukin-6 (IL-6) levels in cats. Saliva samples were obtained from 86 cats that were initially evaluated and classified into three groups: FCGS (n=22), other oral inflammatory conditions (OOIC) (n=27), and controls without oral inflammation (n=37); 25 of the control animals were subsequently excluded from the analysis. Compared with pipetting, absorbent paper points were better tolerated by cats with oral inflammation. In the samples collected by pipetting, the mean IL-6 concentration was higher in the FCGS group (473.10 pg/mL) than in the control group (12.78 pg/mL). A similar pattern was observed in samples collected using absorbent paper points; IL-6 levels were highest in the FCGS group (170.90 pg/mL), followed by the OOIC (6.05 pg/mL) and control (1.50 pg/mL) groups. PGE₂ levels were also highest in the FCGS group (647.52 pg/mL), followed by the control group (182.13 pg/mL) and the OOIC group (111.40 pg/mL). These findings should be interpreted in light of the pilot design, sample exclusions, and absence of a diagnostic reference standard. Nonetheless, salivary assessment appears to be a feasible and promising noninvasive approach for monitoring oral inflammation in cats with FCGS.