Oxidative Stress and Antioxidant Imbalance in Erythema Multiforme: A Cross-sectional Study of Salivary Biomarkers

This cross-sectional study aims to assess levels of antioxidants, including Superoxide Dismutase, Glutathione Peroxidase, Catalase, and Uric acid, in the saliva of patients with erythema multiforme. The saliva samples were collected during the active stage of the disease, approximately 2–4 days after lesion onset. Additionally, correlations were examined to assess differences in antioxidant levels between patients with recurrent episodes and those with a single episode of the disease. An independent t-test was utilized to compare controls with patients, and Pearson correlation analysis was performed for subgroup comparisons.

A total of 45 patients and 45 controls participated in the study. Saliva samples were collected to determine levels of the above antioxidants in both groups. The presence of typical target skin, in addition to a previous prodrome of moderate fever, is considered a diagnostic feature. The patient group was divided into two subgroups: the first subgroup included patients with recurrent EM episodes in the previous year, and the second subgroup included patients with a single episode.

The calculated levels of all measured salivary antioxidants were lower in patients with erythema multiforme than in the control group, with a significant difference in catalase (P-value < 0.05) and a highly significant difference in glutathione peroxidase, uric acid, and superoxide dismutase (P-values < 0.001). The group of patients was further subdivided into those with a single episode of erythema multiforme and those with multiple episodes; the difference was insignificant for all measures except catalase, which was significantly lower in the multiple-episode subgroup (P-value < 0.05).

This study revealed an important difference in antioxidant levels between the control group and EM patients. Definitely, the salivary concentrations of SOD, GSH-Px, and UA in EM patients were particularly lower compared to those in the control group, suggesting that EM patients have a compromised antioxidant defense.

The salivary secretion of erythema multiforme patients demonstrated a modified antioxidant status, characterized by lower levels of these markers compared to those of healthy individuals. These findings reflect association rather than causation due to the cross-sectional design, and longitudinal validation is required. The difference in Catalase levels between the single-episode and multiple-episode erythema multiforme subgroups may reflect differences in oxidative-stress dynamics in recurrent disease, warranting further investigation.