Why is this patient’s vulvar skin tender?

A 57-year-old woman presents with a few month history of tender vulvar skin interfering with intercourse or sitting for extended periods. She is otherwise healthy with no other lesions. She has been menopausal for 5 years without hormone replacement. 

Why is this patient’s vulvar skin tender?

A. Lichen planus
B. Lichen sclerosus
C. Atrophic vaginitis
D. Vulvodynia 
E. HPV

Answer on next page

Answer: Lichen planus

A biopsy confirmed the clinical impression of lichen planus manifested by the lacy white changes seen here. This patient responded initially to a potent topical corticosteroid (clobetasol) with maintenance of benefit with a nonsteroidal anti-inflammatory drug (tacrolimus). This condition can progress with scarring and complete defacement of the vulva. 

Differential diagnosis. Lichen sclerosus usually has an erythematous appearance initially before developing the depigmented sclerotic changes unlike what is seen here. Atrophic vaginitis is within the introitus and not addressed by the clinical photos. Vulvodynia describes the symptomatic pain seen with the patient but does not address the underlying cause. HPV is a reasonable thought that can be confirmed on biopsy if there is any confusion to the diagnosis.