Dr. Fox is a family physician in private practice in Defiance, Ohio, and editor for DynaMed (ww.dynamicmedical.com), a database of comprehensive updated summaries covering nearly 3,000 clinical topics. Dr. Brier is an editor for DynaMed.
Description
• Benign cutaneous papilloma (common wart)
• Single or grouped, rough keratotic papules, nodules, or plaques
ICD-9 codes
• 078.10 viral warts, unspecified
• 078.19 other specified viral warts
Continue Reading
Types
• “Common” warts (verruca vulgaris) are single or grouped, rough keratotic papules, nodules, or plaques.
• Plane warts (verruca plana) are 2-4 mm in diameter, flat-topped with slight elevation and minimal scaling.
• Myrmecial warts have a deep “burrowing” quality.
• Mosaic warts are plantar or palmar warts (verrucae palmaris/verrucae plantaris) that coalesce into large plaques.
• Filiform warts have “frondlike” projections and occur most frequently on the face.
• Periungual warts occur along the nail margins, including proximal nail fold and hyponychium.
• Condyloma acuminata are anogenital warts.
Organs involved
• Skin and mucous membranes, most commonly on fingers, hands, knees, elbows, feet, and face
Prevalence
• Typically affects children and young adults (girls more frequently than boys)
• Estimated at 3.9%-5.3% in 6- to 16-year-olds.
Cause
• Human papillomavirus (HPV) invades epithelial cells with resultant cell proliferation and papule/nodule/plaque formation.
Transmission/risk factors
• Likely low rate of transmission to other people (estimated incidence <10%); however incubation period and duration of virus transmissibility are unknown
• Risk is higher with wet, macerated skin (e.g., communal shower use associated with increased risk of plantar warts).
• Auto-inoculation to secondary sites is common (scratching, shaving, etc.).
• Nail biting and finger sucking can spread infection subungually and periungually.
Associated conditions
• Bowenoid papulosis (premalignant state)
• Squamous cell carcinoma (cervical and some anal, genital, and oropharyngeal cancers)
• Epidermodysplasia verruciformis (autosomal recessive disorder associated with chronic HPV infection)
• Heck’s disease (focal epithelial hyperplasia)
Presentation/diagnosis
• Skin growth, often correctly identified by the patient as a “wart”
• Lesions on the feet or near nails may be painful.
• Biopsy is generally unnecessary but may be appropriate for
— Immunocompromised patients
— Lesions that are of uncertain etiology, resistant to treatment, suspicious for Bowenoid papulosis or squamous cell carcinoma
Differential diagnosis
• For common warts
— Molluscum contagiosum
— Nevus (mole)
— Seborrheic keratosis
— Skin tag
— Actinic keratosis
— Squamous cell carcinoma
— Linear epidermal nevus, inflammatory linear verrucous epidermal nevus
• For plane warts
— Lichen planus
— Lichenoid keratosis
• For plantar wart (calluslike)
— Callus
— Corn
— Talon noir (calcaneal petechiae)
Prognosis
• Often self-limited (spontaneous clearance reported to be 80% within two years)
• Some lesions may grow in size and number over time.
• Lesions may become increasingly resistant to treatment over time.
• Immunosuppressed patients may
— Have more numerous lesions
— Have higher treatment failure rates
— Be at increased risk of malignant transformation to squamous cell carcinoma.
Treatment
• May not be necessary because of self-limited nature of the disease
• Virtually all therapies have limited, firm (replicated) study data supporting them.
— Cryotherapy commonly used
— Duct tape or moleskin
— Topical salicylic acid
— 5-Fluorouracil (5% cream) with occlusive dressing
— Photodynamic therapy with 5-aminolevulinic acid
— Many other treatments that are used but supported only by limited or no clinical data
■ Topical imiquimod
■ Retinoids
■ Cantharidin
■ Bichloroacetic acid
■ Dinitrochlorobenzene solution
■ Silver nitrate solution
■ a-Lactalbumin plus oleic acid
■ Formic acid
■ Zinc
■ Diphencyprone (diphenylcyclopropenone)
■ Ciclopirox-containing lacquer
■ Intralesional injection of skin test antigens
■ Bleomycin
■ Combination of 5-fluorouracil, lidocaine, and epinephrine
■ Laser treatment
■ Oral zinc sulfate, cimetidine, levamisole
■ Hypnotic and “suggestion” therapies, including use of “wart tape”
Prevention
• Avoid barefoot use of communal showers.
• Refrain from scratching or shaving lesions.
• No need for children to be excluded from attending school or participating in sports
For complete references, see www.dynamicmedical.com.
