A shave biopsy revealed acanthosis, papillomatosis, hyperkeratosis, hypergranulosis, parakeratosis, and cytoplasmic viral-like inclusions without atypia, consistent with a diagnosis of a common wart. The biopsy ruled out other possible diagnoses, which included keratoacanthoma, seborrheic keratosis, and squamous cell carcinoma.
Cutaneous warts can manifest as common warts (verruca vulgaris), plantar warts (verruca plantaris), or plane warts (verruca plana). These benign skin lesions are caused by human papillomavirus and can manifest in areas of skin trauma; this is known as the Koebner phenomenon. Most warts can be diagnosed through clinical history and examination. Dermoscopy, if performed, may reveal thrombosed capillaries as dotted structures, but there is an increased risk of cross-contamination.1 That said, some dermatoscopes have disposable covers or can be cleaned with antiviral, antibacterial wipes. If the diagnosis is unclear or the exam is clinically suspicious, a biopsy may be required.
Cases with progressive enlargement and extensive involvement of the skin (as was seen here) are generally associated with certain predisposing conditions, such as atopic dermatitis and immunosuppression.2 Our patient screened negative for HIV infection, and further evaluation did not reveal any concerns for immunosuppression.
Treatment for a common wart depends on patient characteristics, preferences, cost, and possible adverse effects. Standard treatment options are topical salicylic acid and cryotherapy with liquid nitrogen. Depending on the location and type of the wart, multiple treatments may be required, and recurrences are common. Intralesional injection with bleomycin, 5‐fluorouracil, or cidofovir is often used for recurrent and refractory warts.
Patients unable to tolerate cryotherapy or local injections may benefit from thermotherapy by heating the wart with a pulsed dye laser.3 Observation is also a reasonable course of action for new warts, as they may spontaneously resolve within a year.
In this case, the patient opted for over-the-counter salicylic acid 17% to be applied nightly until resolution. Cryosurgery would be a next step for him if the lesion does not resolve after 3 months of treatment.
Image courtesy of Faryal Tahir, MD. Text courtesy of Faryal Tahir, MD, Assistant Professor, and Daniel Stulberg, MD, FAAFP, Professor and Chair, Department of Family and Community Medicine, Western Michigan University Homer Stryker, MD School of Medicine, Kalamazoo.