Despite the abundance of microorganisms in the vulva and perineum, the normal skin is resistant to infection.
The barrier to infection is disrupted if the vulva is continually moist. The most common causes of secondary vulvitis are:
- urinary incontinence
- vaginal discharge
The barrier is reduced in cases of vulval atrophy or degeneration resulting from:
- the low oestrogen levels after the menopause
- vulval dysplasia
Many of these conditions result in pruritus and scratching. The macerated skin is then more prone to further infection.
Infecting organisms include Staphylococci and Candida albicans.
Allergic vulvitis is common. It is caused by sensitivity reactions to chemicals in washing powder, toiletries etc.