Evaluation of serum interleukin-17 in women with vaginitis

Background: Vaginitis is a common condition seen in the field of gynecology and is caused by a wide range of infectious agents. These include bacteria, fungi, and parasites. The immune response to these different etiologies may also differ; examining it could provide information on host-pathogen interactions. Objectives: To assess the serum levels of IL-17 in women with different types of vaginitis and compare these levels with those in healthy controls to try to find an immunological profile corresponding to each etiological agent. Method: Sixty women who had been diagnosed with vaginitis, along with 50 healthy controls, were enrolled at Al-Najaf General Hospital, Iraq, between February 2024 and March 2025. Women who had taken antibiotics or antifungals in a recent episode of chronic disease were excluded; also excluded were pregnant or lactating women. The clinical diagnosis of vaginitis was confirmed by a gynecologist through physical examination and laboratory tests (vaginal pH, wet mount, and whiff test). Serum IL-17 levels were quantified using ELISA. Results: Bacterial infections were identified as the leading cause of vaginitis since 45% was reported. It was followed by fungal infections at 25%, parasitic at 20%, and mixed infections at 10%. The current study found a significantly higher mean IL-17 level in patients with vaginitis (19.34 ± 11.54 pg/ml) compared to controls (14.56 ± 6.22 pg/ml) with a T value of 2.88 and P =0 .029. Subgroup analysis showed that bacterial vaginitis presented the highest concentration of IL-17 (21.7±3.09 pg/ml), significantly greater than in fungal, parasitic, or mixed infections (F =8 .34, P=0 .005). Conclusions: IL-17 levels are high in women with vaginitis. In bacterial infections, since there is an active immunological response mediated by IL-17, it provokes good reaction. This cytokine can also be used as a good biomarker for etiological differentiation of vaginitis as well as pathogen-specific immune responses.