Viral paronychia (herpetic whitlow) is a painful, localized infection of a digit, usually of the distal pulp space, with erythematous and occasionally vesiculopustular eruption. It occurs in children who suck their thumbs, bite their nails, and those with herpetic gingivostomatitis. Herpes gladiatorum occurs in wrestlers and rugby players who acquire cutaneous herpes from close body contact with other players’ cutaneous infections. Cutaneous HSV infection in persons with an underlying skin disorder (e.g., atopic dermatitis) can result in eczema herpeticum (Kaposi varicelliform eruption), a disseminated cutaneous infection. There may be hundreds of herpetic vesicles over the body, usually concentrated in the areas of skin affected by the underlying disorder.
Treatment with oral valacyclovir or famciclovir may shorten duration of disease for primary and recurrent infection. Prophylactic antiviral therapy may be warranted in those with frequent recurrences. Infants, persons with eczema, and persons with immunodeficiency are at increased risk for disseminated and severe HSV disease and should receive intravenous acyclovir therapy.
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Warts are caused by the human papillomaviruses (HPVs),nonenveloped, double-stranded DNA viruses that infect skin and mucous membrane keratinocytes. More than 100 HPV serotypes have been identified, with different serotypes accounting for the variation in location and clinical presentations. There are 15 to 20 oncogenic (high-risk) types, including 16, 18, 31, 33, 35, 39, 45, 51, 52, and 58. HPV types 16 and 18 are associated with 70% of cases of cervical cancer as well as vulvar and vaginal cancers. Common nononcogenic (low-risk) types include 1, 2, 3, 6, 10, 11, 40, 42, 43, 44, and 54. Regardless of the infecting serotype, all warts are associated with hyperplasia of the epidermal cells.
Warts occur at all ages. Common warts (verruca vulgaris),associated with HPV types 1 and 2, are the most common form (71%). They occur frequently in school-age children, with a prevalence of 4% to 20%. They are transmitted by direct contact or by fomites and have an incubation period of approximately 1 month before clinical presentation. The common wart is a painless, well-circumscribed, small (2to 5-mm) papule with a papillated or verrucous surface typically distributed on the fingers, toes, elbows, and knees. They also may be found on the nose, ears, and lips. Filiform warts are verrucous, exophytic, 2-mm papules that have a narrow or pedunculated base. Flat warts (verruca plana) are associated with HPV types 3 and 10 and are multiple, flat-topped 2to 4-mm papules clustered on the dorsal surface of the hands, on the soles of the feet (plantar warts), or on the face. Plantar warts may be painful because of the effect of pressure and friction on the lesions. Genital warts (condylomata acuminata) are associated with the HPV types 6 and 11 (90%). They are flesh-colored, hyperpigmented, or erythematous lesions that are filiform, fungating, or plaquelike in appearance and involve multiple sites on the vulva, vagina, penis, or perineum. Genital warts are the most common sexually transmitted infection, with 1 million new cases annually.