Vulvitis is an inflammation of the vulva that results from various diseases, infections, injuries, allergies or irritants. Common causes include scented products, synthetic fabrics, activities like horseback riding or bicycle riding, and infections. Symptoms include redness, swelling, itching and fluid-filled blisters or sores. Diagnosis involves medical history, exam, and potentially tests for infections. Treatment depends on the underlying cause but may include avoiding irritants, sitz baths and hydrocortisone creams.