Differential diagnosis of vulvar lichen sclerosus
VLS can resemble other vulvar diseases — and some of them can coexist with it. A correct differential diagnosis is the foundation of appropriate treatment.
Why differential diagnosis is clinically relevant
The treatment for VLS is specific — and it differs from the treatment of other vulvar pathologies that can produce similar symptoms. A misdiagnosis means inadequate treatment for months or years, with the progression of the actual disease remaining uncontrolled.
In my practice, a significant portion of patients who arrive with chronic symptoms without a correct diagnosis have been previously treated for a disease they did not have — or only for a part of what they had.
This has an important implication: VLS is not a difficult disease to diagnose when it is looked for. The real problem is different: it is frequently not sought because symptoms are attributed to other causes — recurrent infections, vaginal atrophy due to menopause, contact dermatitis — without performing a targeted examination.
Diseases that can be confused with VLS
Vulvar lichen planus
Vulvar lichen planus is perhaps the most relevant differential diagnosis of VLS. It shares symptoms — itching, burning, dyspareunia — and can produce similar anatomical changes. However, there are important clinical differences: lichen planus tends to produce more prominent erosions, can affect the vaginal mucosa — which VLS does not do — and has a different histological pattern. In some cases, both diseases coexist. Biopsy is especially useful when the clinical distinction is not clear.
Vulvar vitiligo
Vitiligo produces white patches on the skin that can be confused with those of VLS. The fundamental difference is that vitiligo is a loss of pigmentation without inflammation or structural changes: skin affected by vitiligo has a normal appearance and texture, without atrophy or symptoms. VLS produces hypopigmentation associated with changes in texture and symptoms. Careful examination and clinical history allow them to be distinguished in most cases.
Vulvar contact dermatitis
Vulvar contact dermatitis produces itching, erythema and, in some cases, skin changes that can be reminiscent of VLS. The differential key lies in the history of exposure to an irritant or allergen — soaps, pads, condoms, hygiene products — and in the resolution of symptoms upon eliminating the causal agent. Contact dermatitis does not produce the structural changes of VLS. However, it can coexist with it and aggravate symptoms.
Lichen simplex chronicus
Lichen simplex chronicus is a skin response to chronic scratching: it produces thickening and lichenification of the tissue. It can coexist with VLS — the pruritus of VLS induces the scratching that produces lichen simplex — and its clinical distinction can be difficult. Biopsy provides useful histological information in these cases.
Vulvar psoriasis
Psoriasis can affect the vulvar area and produce itching, erythema, and skin changes. It is distinguished from VLS by its more erythematous than whitish appearance, the absence of atrophy, and the frequent presence of psoriasis in other locations of the body. Clinical history and a complete examination are usually sufficient to distinguish them.
Genitourinary atrophy
Genitourinary syndrome of menopause (vulvovaginal atrophy)
Vulvovaginal atrophy due to hypoestrogenism produces dryness, itching, burning, and dyspareunia — symptoms that overlap with those of VLS. The difference lies in the clinical appearance: atrophy produces uniform thinning of the epithelium without the whitish changes or anatomical changes of VLS. Furthermore, atrophy responds well to local estrogen treatment, whereas VLS does not. Both can coexist.
When several diseases coexist
A clinically relevant point that is frequently overlooked: VLS can coexist with other vulvar pathologies. A patient may have VLS and contact dermatitis, or VLS and vulvovaginal atrophy, or VLS and lichen planus. In these cases, treating only one of the diseases yields a partial response — and the specialist may incorrectly interpret that the treatment is not working.
A complete differential diagnosis is not simply choosing between A or B: it is evaluating whether A, B, and C may be present simultaneously.