Cutaneous Infections – Viral Warts, Bacteria and Onychomycosis

Question 1

Virology
Viral Wart/Derm
Infections

Answer 1

 Non-enveloped, ds-DNA virus
 55nm in diameter (in comparison HSV virus is 100nm)
 Can only complete replication cycle in squamous epithelium
early E genes: Responsible for transformation, DNA replication and transcription

Later L genes:
- Major structural proteins, 95% of
virion protein. Forms capsomere and capsid. Initiate binding to cell surface
- Major structural proteins, 95% of
virion protein. Forms capsomere and capsid. Initiate
binding to cell surface

Question 2

Viral Wart/Derm
Infections
Epidemiology

Answer 2

pool deck
 Ubiquitous virus found in the environment
 Most easily acquired from water-borne contact or close
contact with an infected individual
 Usually through small micro-abrasions in the skin

Question 3

Cutaneous or Common warts

Answer 3

 Prevalence in general population is thought to be 7-12%
 Mostly asymptomatic, but can be painful or cause discomfort
 NO definitive therapy

Question 4

Genital Warts

Answer 4

 HPV 6, 11 are low risk viruses associated with 75% of warts
 Non-oncogenic
 HPV 16, 18 are high risk viruses associated with 90% of cervical and
anogenital carcionmas
 Thought to progress:
SIL CIN I CIN II CIN III carcinoma in situ cervical cancer

Question 5

Clinical course

Answer 5

Most warts resolve without therapy
 2/3 of warts resolve without treatment in two years
 Asymptomatic warts in non-cosmetically sensitive areas do not require trearment
 However, patients request treatment for cosmesis, discomfort, pain and to limit potential spread

 Also, warts should be treated in high risk situations:
 Immunosuppresed or immunocompromised patients
 Ano/genital/mucosal areas with a higher risk of malignant transformation
 Patients that are immunodeficient
 Patients with extensive history of sun exposure and
skin malignancies, radiation, etc….

 CDC estimates 90% of HPV infections cleared in 2 years
 Cleared vs suppressed to undetectable levels?

Question 6

can it spread or cause cancer?

Answer 6

 Good news: In a non-detectable state it cannot spread or
cause cancer
 Bad news: However, it can re-activate – possibly years later
 Therefore, need to remain vigilant, consider periodic
examinations (skin exams, pap smear)

Question 7

HPV Types

of cutaneous warts

Answer 7

Palmar / Plantar
•HPV Types 1, 2, 27, 57
•Thick, endophytic, sloping sides, central
depression
•Can be painful
•Resistant to treatment

Common
•HPV Types 1, 2, 4, 27, 57
•Fingers, knees, elbows, nailfold
•Hyperkeratotic, exophytic, dome shaped,
punctate black dots

Flat
•HPV Types 3, 10, 28 and 29
•Skin colored or pink, smooth surface, flat
topped
•Mainly dorsal hands, arms and face

Tumors (Bowen’s, KA, SCC)
•HPV types 16, 48, 25, 37
•Bleeding, crusted, ulcerated or volcanoe-like
nodules
•Usually sun exposed areas

Question 8

HPV Types

of mucosal warts

Answer 8

Condyloma acuminate
•HPV Type 6, 11
•Discrete, sessile, smooth, exophytic, skin colored
to brown to white
•Genitals, perineum, anal canal, inguinal fold,
suprapubic

High Grade IEN
•HPV Type 16, 18
•Condyloma plana
•Bowenoid papulosis (red brown warty papules
or plaques)
•Erythroplasia (velvety red plaques)

Verrucous Carcinoma
•HPV Type 6, 11
•Buschke-Lowenstein
•Oral florid papillomatosis
•Epithelioma cuniculatum
•Papillomatosis cutis carcinoides

Other
•HPV type 6, 11
•Oral warts
•Recurrent respiratory papillomatosis
•Focal epithelial hyperplasia (Heck’s syndrome)
•Viral associated trichodyspalsia

Question 9

Molluscum contagiosum

Answer 9

 DNA pox virus
 Highly prevalent in children, less so as we age
 Generally self resolving, can take months to years
 Treated similarly to warts

Question 10

wart appearance

Answer 10

xophytic
nodule sticking out of the skein with
those little black dots

flat warts: more skin colour and dont raise up out of skin, can spread

Question 11

Seborrheic keratosis

Answer 11

 Harmless skin thickenings all of us develop over time
 Can show up anywhere on the body
 Due to genetics, age and possibly irritation of skin
 Can be treated with liquid nitrogen or excision
theyre more flat topped, not contagious

Question 12

Skin tags

Answer 12

Small, harmless, fleshy, pedunculated pieces of skin
 Usually found in axilla, groin and neck
 Can be treated with liquid nitrogen or excisio

Question 13

Pearly penile papules

Answer 13

 Small dome shaped or fleshy papules located on the glans
penis only
 Normal variant
 Can be treated with laser, LN2, ED, surgery, etc…
dont need to be treated not infectious

Question 14

Keratoacanthoma

Answer 14

 Low grade form of squamous cell carcinoma arising from hair follicle cells
 Controversial designation
 Some KAs appear to be related to infection with HPV
 Majority of KAs are not related to HPV infection
 Usually surgically removed

Question 15

Corns and Callus

Answer 15

 Thickenings of skin on pressure bearing areas of the body,
usually painful or cause discomfort
 Common on feet and toes
 When a callus (tyloma) develops a mass of dead keratinocytes at its centre it becomes a corn (heloma)

Treatment is pressure offloading

Question 16

Syringomas

Answer 16

 Small overgrowth of eccrine sweat glands found usually periorbitally
there for life
 Benign and harmless
 Difficult to treat, can use electrocautery or lasers

Question 17

Lichen striatus

Answer 17

type of rash
 Inflammatory, lichenoid dermatitis usually affecting children
 Consists of skin colored, monomorphic, small papules
coalescing into a linear plaque; usually on one extremity
 Treated with topical corticosteroids

Question 18

Actinic keratosis

cutaneous horn on picture

Answer 18

 Sun damaged pre-cancerous area of skin
 Usually sun exposed areas – face, scalp, hands, arms
 Can be small, red, scaly patches and more hyperkeratotic or
horn-like variants
 Multiple treatment options

Question 19

Treatment Paradigm

Answer 19

1. Do no harm
2. Confirm it is a wart (do not forget about the mimics)
   If there is doubt, can always biopsy
3. Start with topical therapy and/or physical modalities
4. Progress to alternative topical and/or physical therapy
5. When in doubt – refer

Question 20

Treatment Paradigm

Answer 20

 1st Line
 Topical salicylic or tri-chloroacetic acid

 2nd Line
 Cryotherapy with LN2

 3rd Line
 Everything else

Question 21

Topicals

Answer 21

 Salicylic acid: 20-40% in petrolatum
 Cochrane review found evidence of benefit
 Soak wart, pare it down, treat with SA under
occlusion
 Treat at least 12 weeks
 Others
 Tricholoracetic acid, glycolic acid

DPC
 Topical contact allergen, 60-80% response
 Various concentrations and application techniques
 SE = inflammation, blistering, ‘doughnut’ warts
- induce allergy on skin (poison ivy and get it to react, scabbing crusting rxn to wipe out the wart)
- painful or sore, middle may clear out, get doughnot shaped one

Question 22

topicals retinoids, canth

Answer 22

Retinoids
 High concentration retinoids
 Flat warts
 SE = inflammation
 Limited studies show benefits equivalent to LN2

Cantharidin
 Blistering agent derived from Cantharis
vesicatoria beetle
 Apply, wash off between 6-24 hours
 Repeat every 2 weeks
 Cure rates up to 80%
 SE = pain, blister, doughnut wart

Question 23

topicals Imiquimod, Podophyllotoxin, Podophyllin

Answer 23

 Imiquimod
 5% imiquimod M/W/F up to daily for 16 weeks
 3.75% imiquimod daily for up to 6 weeks
 Condyloma acuminate
 Via TLR7 and 8, activation of cytokine
secretion from monocytes and macrophages,
stimulation of dendritic cells
 30% response rate with genital warts
 SE = pain, blistering, flu-like symptoms, edema

 Podophyllotoxin
 0.5% applied BID 3 days per week
 SE = erythema, pain and induce mitosis
OTC

 Podophyllin
 25% tincture of benzoin, apply weekly for 4-6 weeks
 Wash off after 4-8hrs
 SE = mutagenic, case reports of fetal loss
more conc and do it in office

Question 24

topicals Flurouracil

Answer 24

Flurouracil
 5% cream
 1% + 10% salicylic acid
 2X/week
 Can apply for weeks to months
 SE = inflammation (redness, crusting, pain,
scabbing, erythema…)
 Limited studies have shown clearance in 19/20
pts

 Sinecatechin
 10% ointment
 Green tea extract
 MOA unknown
 3 times daily for up to 16 weeks
 Overall clearance rate of 52.4%
 SE= local inflammation, erythema, pain, ulcer, edema

Question 25

Oral

Answer 25

 Cimetidine (H2 antagonist, activates Th1 cells to produce
IL-2 and IFN)
 20-40mg/kg divided bid
 Variable rates of efficacy from no difference from
placebo to 86% clearance in children

found to activate th1 cells to male IL2 and INF , enhance immune system to attack warts

Question 26

Physical therapies

Answer 26

 Cryotherapy / LN2
 2 freeze-thaw cycles
 Multiple treatments, q1-4 weekly
 Remission rates of 78-88% with 21-39% of patients
developing recurrence
 Laser
 CO2
 V-beam
 PDT

Question 27

Physical - Surgical

Answer 27

surgical:  Electrosurgery
 Curettage
 Scalpel excision or paring
 Scissors

Question 28

Vaccines

Answer 28

 Newer generation of vaccines
 Gardasil 9
 Nonavalent vaccine HPV 6, 11, 16, 18, 31, 33, 45, 52 and 58
 Ages 9-14 years: 2 dose (0 and 6 month) and 3 doses (0, 2 and 6 month)
 Ages 15-26 years: 3 doses (0, 2 and 6 months)
 Cervarix 9
 Nonavalent vaccine HPV 6, 11, 16, 18, 31, 33, 45, 52 and 58
 Not yet available here

 90% efficacy against HPV infection and 100% protection against genital warts, low grade dysplasia and high grade dysplasia
 Not meant as a treatment for active HPV infection
 Some rare case reports of active HPV disappearing after vaccine