Derm Packet #4-Viral and Fungal Skin Infections

What is the etiologic agent of warts?

human papilloma virus (HPV)

How many serotypes of HPV are there?

over 100

non-gential warts

common (hands/feet), periungual (around fingernails and toenails), flat, filiform (long, threadlike), and plantar types

genital warts (condyloma acuminata)

strains 6 and 11 cause 90%

How many strains are high risk for cancer?

12, but 70% is caused by 16/18

common warts (verruca vulgaris)

dome shaped with irregular surfaces, common in children

Where are verruca vulgaris most common?

hands and knees, but can occur anywhere on the body

How are verruca vulgaris spread?

skin to skin contact, contact with contaminated surfaces, and autoinoculation

autoinoculation

refers to spreading a microorganism by contact with a lesion on one's own body

common wart treatment

-first-line treatment: salicylic acid (Compound W) apply to wart as liquid 1-2x a day (OTC and inexpensive)

-liquid nitrogen: two freeze-thaw cycles (one cycle is up to 3 min) are administered every 2-4 weeks for several visits

-surgical removal (scalpel) or laser therapy (vaporization of warts) only if recurrent

-benign neglect: leave them alone and sometimes they resolve on their own (could be 1-2 years)

*its common for viral infections to come back until immunity is built against it, so the warts could come back with any of these treatments*

plantar wart

occur on the plantar surfaces of the feet. because of the forces on the feet from walking, the warts grow into the foot and become calloused (harder to treat, harder to eradicate)

can be very painful if walked on a lot

may resolve spontaneously with no therapy

in immunocompromised patients, may be widespread and intractable

Why are plantar warts so resilient?

every wart has its own supply of blood and nerves

solitary wart

on its own

mosaic wart

many, form patterns

plantar wart treatmemt

-cut duct tape size of lesion and leave in place for 6 days, remove, wash skin, and gently debride (this removes the oxygen), can be repeated until it goes away

-OTC topical salicylic acid preparations used for 8-12 weeks, cure rate is 75% (might be initial treatment)

-cryotherapy ablation with liquid nitrogen, cure rate is 50%

-prior to surgery/laser can scrape off calloused skin with a razor blade to help penetrate blood supply

-surgical removal/laser treatment (may still recur)

What treatment should not be used with diabetics?

salicylic acid

debride

rub off skin, specifically dead tissue

deep palmoplantar warts (myrmecia)

type of plantar wart characterized by a deeper, endophytic growth pattern and are often associated with HPV type 1, showing a distinct histological appearance with keratohyalin inclusions

flat warts

smooth, skin colored lesions that develop on the face, trunk, elbows, and knees

heck disease

is a cutaneous condition characterized by white to pinkish papules that occur diffusely in the oral cavity. It is caused by the human papilloma virus types 13 and 32.

buccal/gingival mucosal tissue, tongue/upper lip

condyloma acuminata

infection of genital or anal skin by HPV, lesions spread rapidly over moist areas as well as symmetric surfaces of the labia or rectum

What HPV serotypes are responsible for >90% of genital warts?

6 & 11

What do condyloma lesions look like?

lesions are pale pink to white, warty-like raised papules, may coalesce to form large cauliflower like masses

How to identify condyloma acuminata

identification may be difficult

use white vinegar (acetic acid) to bathe the suspected lesion. if acuminata, lesion will turn white

make sure to separate labia

pap smear, biopsy, colposcopy might be used to make the diagnosis (easier way to look at cervix if you think the cervix has warts)

condyloma acuminata treatmemt

podofilox (Condylox) is applied by pt twice daily x 3 consecutive days a week for cycles of 4-6 weeks

imiquimod (Aldara) 5% cream once daily on 3 alternate days per week for 8-12 weeks

surgical removal may be indicated in cases resistant to other treatments (usually last step)

electric cauterization

condyloma acuminata prevention

Gardasil: vaccine-most cases of cervical cancer are caused by genital warts

herpes simplex

viral infection, primary or recurrent, characterized by grouped vesicles on an erythematous base on skin or mucous membrane

types of herpes simplex

type 1 (HSV1) or type 2 (HSV2)

herpes simplex transmission

skin to skin, skin to mucosa, mucosa to mucosa (viral shedding)

herpes simplex primary infection

occurs with multiple, painful lesions, fever, lymphadenopathy, general malaise (might just not feel right)

herpes simplex secondary lesions

have similar lesions and symptoms but less severe, shorter duration, 1-2 weeks

prodrome

sometimes can tell outbreak is coming from tingling/itching

herpes simplex treatment

Acyclovir 200mg TT tab po TID x7-10 days (only comes in 200 mg tab)

Valacyclovir, Famcyclovir

What's another name for herpes zoster?

shingles

herpes zoster

decline in t cell mediated immunity to VSV (varicella zoster virus), reactivation of varicella virus due to cold, stress, age, medical conditions

herpes zoster symptoms

unilateral pain (key to this, pain doesn't cross midline), vesicular lesions limited to a dermatome, pain/burning.itching will often precede rash (1-5 days), presents as clustered vesicles of varying sizes, lesions do not cross midline of the body, lesions continue to develop for 3-5 days, scab over in approx 10 days

herpes zoster treatment

Acyclovir 800mg 5x per day x 7 days, valacyclovir, famcyclovir

give within 72 hours of symptoms to prevent post-herpetic neuralgia and shorten course

pain management incudes topical cream, Tylenol, advil, narcotics (don't love to use narcotics cuz tolerance/addiction)

post herpetic neuralgia

continuance of pain, burning after lesions go away, pts might take meds/ go away on own, pts still have bad pain to nerve root, lasts > 3 months after lesions resolve

most common complication, risk increases with age

herpes zoster complications

herpes zoster ophthalmicus, Ramsay-Hunt syndrome, post herpetic neuralgia, encephalitis

herpes zoster ophthalmicus

goes into eye, needs to go to optomologist

ramsay-hunt syndrome

facial nerve affected, not common, paralysis/hearing loss

encephalitis

inflammation of the brain

herpes zoster prevention

zostavax: shingles vaccine recommended by CDC for pts over 60 for routine immunization, helps reduce the risk of developing shingles and post herpetic neuralgia

vaccination against varicella: chicken pox vaccine, most pts won't remember if they had it or not since they were most likely children

fungal skin diseases

superficial fungal infections are the most common of mucocutaneous infections

two common groups of fungal skin diseases

dermatophytes and candida (yeast)

dermatophytes

unique fungi that infect nonviable keratinized cutaneous structures

What's another name for dermatophytes?

tinea

How are dermatophytes classified?

according to their site of infection

tinea corporis

presents as irregularly shaped scaly patches and plaques, often with a raised erythematous border and central clearing, occurs on the trunk arm and leg, may be a single lesion or multiple lesions, more commonly known as ringworm

tinea corporis treatment

topical antifungals (cream/lotions)

tinea capitis

"ringworm" of the scalp, usually occurs in children from 2-10 years old

wide range of presentations including, scaling, broken hair, painful inflammation and possible scarring alopecia

make sure to separate all hair and take time with PE

alopecia

hair loss

tinea capitis treatment

oral antifungals (topical antifungals only if hair is short and only small areas affected, long hair won't be penetrate-able with topicals_

tinea pedis

dermatophyte infection of the feet, "Athlete's foot"

erythema, scaling, erosions, macerations, and/or bullae

often asymptomatic, but may be associated with itching

tinea pedis prevention

use of shower shoes in public facilities, keep feet dry

tinea pedis treatmemt

topical antifungals

tinea cruris

dermatophytosis of the groin, pubic regions, and thigh, lesions are large, scaling well demarcated dell red to brown plaques, asymptomatic or mild itching

What is tinea cruris called in men?

jock itch

predisposing factors of tinea cruris

jumidity, tight clothing, obesity

tinea cruris treatment

topical antifungals

list of topical antifungals

Clotrimazole twice daily, OTC

Econazole (spectazole) once daily, Rx only

Ketoconazole once daily, Rx only

Miconazole twice daily, OTC

candida

fungal infection caused by yeast, most commonly candida albicans, but can also be candida globerata or candida tropicalis

candidal infections can affect any anatomical structure

the very young and very old are at greatest risk, as well as those with compromised immune systems

thrush

oral candiditis treated with medicated mouth wash

intertrigo

candida infection in the intertriginous areas (two skin surfaces rub together)

rash begins with vesiculopustules which rupture, causing maceration

lesions coalesce and satellite lesions are visible near the margins

intertrigo treatment

topical: nystatin, clotrimazole

oral: fluconazole (difclucan) 1 day pill, 150 mg