Is this asymptomatic penile lesion an HPV infection?

Case 4:

For several weeks, a 33-year-old man has had an asymptomatic lesion on the head of the penis. He has had a new sex partner in the past few months but is unaware of any health problems she may have. What is the likely cause of this lesion?

A. Seborrhea.
B. Psoriasis.
C. Lichen planus.
D. Human papillomavirus (HPV) infection.
E. Contact dermatitis.

Answers on next page

Lichen planus, C, is characterized by its violaceous color; polygonal shape; and, sometimes, fine scale. This papular eruption is most commonly found on the flexor surfaces of the upper extremities, on the genitalia, and on the mucous membranes. Genital involvement is common in men with cutaneous disease; typically, an annular configuration of papules occurs on the glans. Lichen planus is probably an immunologically mediated reaction.

Mild cases can be treated with topical corticosteroids, preferably non-halogenated. Topical immunosuppressives, such as tacrolimus, have also been effective.

Seborrhea and psoriasis feature more scale than this patient's lesion. HPV infection in men causes genital warts, which can appear as flat papules and should be considered in the differential. Contact dermatitis was excluded by lack of an exposure history and would be expected to have more scaling associated with itching.