Plantar Wart

1. See Also
   1. Verruca plana (Flat wart)
   2. Verruca Vulgaris (Common Wart)
   3. Condyloma acuminata (Genital Wart)
   4. Molluscum Contagiosum
2. Epidemiology
   1. More common in adolescents and young adults
   2. Plantar Warts responsible for a third of warts
3. Pathophysiology
   1. Human Papillomavirus types 1,2 and 4 most common
4. Predisposing factors
   1. Excessive sweating
   2. Repetitive microtrauma to foot (e.g. sports)
   3. Public showers
5. Types
   1. Classic Plantar Wart
   2. Mosaic Wart (coalescence of multiple lesions)
   3. Myrmecia (refers to anthill-like lesion)
      1. Epidermal lesion extends deeply under skin surface
      2. Usually associated with HPV Type 1
6. Symptoms
   1. Pain at heel and Metatarsal heads (pressure points)
   2. Worse with walking (feels like pebble in shoe)
7. Signs
   1. Location
      1. Pressure points on Metatarsal heads or heel
   2. Characteristics
      1. Skin-colored hyperkeratotic Papules or Plaques
      2. Minute, hemorrhagic puncta (visible after paring)
         1. Represent thrombosed capillaries
   3. Accentuated by
      1. Soak in warm water 15-20 minutes to make more visible
8. Differential diagnosis
   1. Corn (or callus)
      1. Yellow-white firm glistening central kernel (pared)
      2. Painless on lateral pressure
      3. Retain normal fingerprint lines (warts do not)
      4. Contrast with pinpoint blood vessels of Plantar Warts
   2. Stress Fracture
   3. Foreign body reaction
   4. Lichen Planus
   5. Black Dot Heel (sheering trauma in sports)
   6. Epithioma cuniculatum (verrucous carcinoma)
9. Precautions
   1. No treatment needed if asymptomatic
   2. Avoid aggressive technique
      1. Electrodessication and Curettage
      2. Surgical excision
      3. CO2 Laser
10. Management
    1. General
       1. Topical treatments require 2-3 months for eradication
       2. Relieve pressure on wart area with pads
    2. Soak foot before application of salicylic acid
       1. Soak in warm water for 15-30 minutes
       2. Apply Mediplast or Occlusal to lesion overnight
       3. Remove in morning and use a loofa pad
       4. Repeat as often as nightly
    3. Salicylic Acid Plasters 40% (Mediplast)
       1. Effective over the course of months
    4. Salicylic Acid 17% in flexible collodion (Occlusal)
       1. Does not slip like plasters
       2. As effective as Cryotherapy
       3. See also Keratolytic Agents
    5. Canthacur PS (SEE Cantharidin)
       1. Use after soaking feet in hot water 10-15 minutes
       2. Occlude with tape
       3. Remove after 48 hours
    6. Intralesional Bleomycin
       1. Performed by dermatology in refractory cases
       2. Contraindicated in pregnancy
    7. Cryotherapy
       1. Use caution on weight bearing plantar surfaces
       2. Risk of painful scarring
11. Management: Blunt surgical dissection
    1. Precautions
       1. Careful! Risk of painful scarring if too deep
          1. Do not enter Dermis on dissection
       2. More effective than electrosurgical techniques (ED&C)
    2. Efficacy: 90% cure rate
    3. Technique
       1. See Blunt Dissection
       2. After lesion removed consider Keratolytic agent
          1. Cover normal skin with Vaseline (petroleum jelly)
          2. Apply 88% Trichloroacetic acid
    4. References
       1. Pringle (1973) Arch Dermatol 108:79-82
12. Course
    1. Recurrence after treatment is common
13. References
    1. Landow (1996) Postgrad Med 99(3):245-9
    2. Miller (1996) Am Fam Physician 53(1):135-43
    3. Ordoukhanian (1997) Postgrad Med 101(2):223-35
    4. Plasencia (2000) Prim Care 27(2)