Introduction
Viral Warts is an infections caused by human papilloma viruses (HPV); include more than 80 types.
- Transferred between humans, or from animals to humans
- Cause cutaneous tumours which tend to regress spontaneously but may rarely progress into cutaneous malignancies
Symptoms and Clinical features of viral warts
Infection may be clinical, subclinical, or latent
- Clinical lesions are visible by gross inspection
- Subclinical lesions may be seen only by aided examination (e.g. the use of acetic acid soaking)
- Latent infection:
- HPV virus or viral genome is present in apparently normal skin
- Thought to be common, especially in genital warts, and explains in part the failure of destructive methods to
eradicate warts
- Incubation period is highly variable; from weeks to years
- Auto-inoculation is the rule
- Lesions may also occur on scratches
(Koebner phenomenon)
Lesions are classified according to their positions and shape:
Common warts
- Firm growths with rough surface; round or irregular, greyish or brown
- Generally appear on areas that are frequently injured, such as the fingers, around the nails (periungual warts); knees, face and scalp
Plantar warts
- Develop on the soles of the feet, where they are usually flattened by the pressure of walking
- A reactive callus forms around lesions
- Multiple warts may coalesce, resembling a tile or mosaic floor (mosaic warts)
- May be extremely tender
- Unlike corns and calluses, plantar warts tend to bleed from many tiny spots, like pinpoints when pared down with a blade
Filiform warts
- Long, thin, small growths that usually crop up on the eyelids, face, neck, or lips
- People who chronically use corticosteroids as cosmetic bleaching creams are prone to multiple filiform warts
Plane warts
- More common in children and young adult.
- Usually appear in groups as smooth, yellow brown, small, flat papules; most frequently on the face
Genital warts
- Occur most often on warm, moist surfaces of the body In men, usual sites are the end and shaft of the penis, and below the foreskin (if uncircumcised)
- In women, lesions occur on the vulva, vaginal wall, cervix, and skin surrounding the vaginal area May develop in the perianal region or rectum
- Especially in homosexual men, and in women who engage in anal sex
- Usually appear 1-6 months after infection as soft erythematous papules, which may be greyish if hyperkeratotic
- New lesions develop rapidly and all coalesce, producing a cauliflower-like picture May grow rapidly in pregnant women, and immunocompromised patients
Differential diagnoses
Common warts
- Keratoacanthoma
- Squamous cell carcinoma
- Seborrhoeic keratosis
- Hypertrophic lichen planus
- Tuberculosis
- verrucosa cutis
- Palmoplantar keratoderma
- Arsenical keratoses
Plane warts
- Epidermodysplasia verruciformis
- Syringomas
- Dermatosis papulosa nigra
- Lichen planus
- Lichen nitidus
Genital warts
- Condyloma lata
- Pemphigus vegetans
Complications of viral warts
- Squamous cell carcinoma of the perianal skin
- Cervical carcinoma from anogenital warts
- Obstructive laryngeal papillomatosis in babies infected through maternal birth canal
Investigations
- Histopathology if in doubt
Management
- Treatment depends on their location, type, and severity, as well as duration of lesions
Treatment objectives
- Eradicate the skin lesions
- Prevent complications
Non-drug treatment
- Liquid nitrogen freeze
- Electro-desiccation
- Laser surgery
Drug treatment
Salicylic acid with lactic acid plaster
- Apply carefully to wart; rub wart surface gently with file or pumice stone once weekly
- May need to treat for as long as 3 months
Podophyllum resin
- Apply weekly under supervision e.g. in genitourinary clinic
Imiquimod 5% cream
- Apply thinly once daily on 3 alternate days per week until lesions resolve (maximum 16 weeks)
Notable adverse drug reactions, caution and contraindications
Salicylic acid plaster
- Avoid broken skin
- Not suitable for anogenital region or large areas
Podophyllum
- Avoid normal skin and open wounds
- Keep away from face
- Should not stay on treated skin for more than 6 hours before washing
Prevention
- Women with genital HPV infection should have routine cervical cytologic screening
- Pappanicolaou (PAP) smear to detect cervical dysplasia