Verruca vulgaris

The biopsy will demonstrate a compact stratum corneum, coarse hypergranulosis, and papillomatosis. The papillomatosis often curves inward. Vascular ectasia is common. Koilocytes (vacuolated cells with hyperchromatic shriveled nuclei) may be present. Red cytoplasmic inclusions may sometimes be present.

Myrmecia

Myrmecia are associated with human papillomavirus 1 (HPV-1).

Verruca plana (flat wart)

Epidermodysplasia verruciformis (EDV)

Condyloma acuminatum

Condylomata acuminata commonly have horn cysts and resemble seborrheic keratoses. The two are differentiated by areas of compact stratum corneum, round parakeratosis, coarse hypergranulosis, and vacuolated keratinocytes with large gray nuclei. In situ hybridization can identify the human papillomavirus (HPV) type.

Bowenoid papulosis

Bowenoid papulosis presents as discrete pink, brown, or gray lesions in the genitalia. They are typically sessile, rather than papillomatous or cauliflower-like. The histologic spectrum ranges from that of a condyloma with buckshot scatter of atypical cells to full-thickness atypia, indistinguishable from Bowen’s disease.

Heck’s disease

Verrucous cyst (cystic papilloma)

Verrucous cysts may arise as a result of papillomavirus infection of a hair follicle. On plantar surfaces, they may arise from eccrine ducts and the lining is more likely to resemble myrmecia.

Herpes simplex

Herpes zoster (varicella-zoster virus: VZV)

Chicken pox (VZV)

Verrucous VZV infection

Multinucleated giant cells with basophilic nuclear rims and nuclear molding are noted within follicular epithelium. This pattern is typically seen in immunosuppressed patients, especially in the setting of human immunodeficiency virus (HIV) infection.

Cytomegalovirus