Cutaneous Infections – Viral Warts, Bacteria and Onychomycosis Flashcards
Virology
Viral Wart/Derm
Infections
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
Viral Wart/Derm
Infections
Epidemiology
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
Cutaneous or Common warts
Prevalence in general population is thought to be 7-12%
Mostly asymptomatic, but can be painful or cause discomfort
NO definitive therapy
Genital Warts
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
Clinical course
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?
can it spread or cause cancer?
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)
HPV Types
of cutaneous warts
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
HPV Types
of mucosal warts
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
Molluscum contagiosum
DNA pox virus
Highly prevalent in children, less so as we age
Generally self resolving, can take months to years
Treated similarly to warts
wart appearance
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
Seborrheic keratosis
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
Skin tags
Small, harmless, fleshy, pedunculated pieces of skin
Usually found in axilla, groin and neck
Can be treated with liquid nitrogen or excisio
Pearly penile papules
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
Keratoacanthoma
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
Corns and Callus
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
Syringomas
Small overgrowth of eccrine sweat glands found usually periorbitally
there for life
Benign and harmless
Difficult to treat, can use electrocautery or lasers
Lichen striatus
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
Actinic keratosis
cutaneous horn on picture
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
Treatment Paradigm
- Do no harm
- Confirm it is a wart (do not forget about the mimics)
If there is doubt, can always biopsy - Start with topical therapy and/or physical modalities
- Progress to alternative topical and/or physical therapy
- When in doubt – refer
Treatment Paradigm
1st Line
Topical salicylic or tri-chloroacetic acid
2nd Line
Cryotherapy with LN2
3rd Line
Everything else
Topicals
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
topicals retinoids, canth
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
topicals Imiquimod, Podophyllotoxin, Podophyllin
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
topicals Flurouracil
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
Oral
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
Physical therapies
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
Physical - Surgical
surgical: Electrosurgery
Curettage
Scalpel excision or paring
Scissors
Vaccines
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
