Vulvodynia is a chronic pain syndrome with unknown etiology, characterized by burning pain of the vulva, affecting up to 16% of women in the US. The objective of this study is to compare the multiple cytokine expression in vestibulodynia patients versus normal control women.
Vaginal rinses were collected from 32 vestibulodynia patients and 26 matched healthy volunteers. All participants signed written informed consent. Aliquots were kept frozen and later semi-quantitative detection of 40 human cytokines was done, using Ray-Biotech Human Inflammation Antibody Array C3. The chemiluminescence detection of the products was performed using x-ray films. Numerical densitometry data were obtained using NIH software program ImageJ, 1.49r. Statistical analysis was done by performing Student's t test (2 tails, unequal variances), and using Excel's Analysis ToolPak.
IL-8 was statistically significantly increased (1.7 times, P=.00021) in vestibulodynia patients vs controls. Interleukins GM-CFS, MCSF, and IL-10 were elevated in vestibulodynia patients 1.27, 1.2, and 1.22 times, respectively, although this increase was not statistically significant. Interleukins IL-1β, RANTES, IL-2, IL-15, TGF-β1, IL-16, TNF-α, IL-4, IL-17, IP-10, EOTAXIN-1 and -2, IL-6, IL-6sR, MCP-1, G-CFS, TIMP-2, PDGF-BB, I-309, MIP-1β, IL-1α, MIP-1δ were statistically significantly (P<.001, or P<.005) decreased in vestibulodynia patients in comparison with healthy volunteers.
These new findings about the cytokine and chemokine profile in vestibulodynia suggests that vestibulodynia is a non-classical inflammatory condition and cytokine-mediated pain syndrome. Additional research needs to be conducted to explore the increase in IL-8 and the decrease of other inflammation markers to understand and be able to develop therapies for vestibulodynia.
Stony Brook University School of Medicine, Stony Brook, NY
Financial Disclosure: The authors did not report any potential conflicts of interest.