Transcript Chapter 33 Fungus

Chapter 33. Topical Fungal
Infections
Revised 8/15/10
Fungal Prevalence
20% of U.S. residents may be affected
Tinea pedis most common
Tinea corporis, cruris next most common
Tinea capitis incidence falling
Fungal Epidemiology: General
High temperature
High humidity
More common: tropical and subtropical areas
Immunocompromised patients
Those with mild skin trauma or maceration
from occlusion
Tinea Pedis Epidemiology
Athlete’s foot; ringworm of foot
White urban dwellers
Adults ages 15-40; more common in males
Those using communal bathing facilities,
swimming pools, summer camps, sports clubs,
gyms
Marathon running: foot trauma
Tinea Corporis Epidemiology
Ringworm of the body
From persons or animals (cat/dog)
Transfer from tinea capitis
Most common prepubertal tinea (day-care center spread
common)
Warm climates, overweight, stress
Tinea corporis gladiatorum: wrestling transmission
Tinea Cruris Epidemiology
Jock itch
Summer
Intertriginous skin: maceration facilitates warm,
moist environment
More in males, scrotal skin folds
Rare in prepubertal children
Postpubertal males 18-40 highest risk group
Tinea Capitis Epidemiology
Ringworm of scalp
More in pediatrics; poorer hygiene
Playing with infected brushes, combs, toys,
telephones
Contacting infected cat or dog
Black children: occlusive hair dressings/ tight
braids
Tinea Unguium Epidemiology
Onychomycosis
30% of those over the age of 60
Toenails of those who also have tinea pedis
Tinea Versicolor Epidemiology
Warm, humid weather
Underlying immune deficiency
Oily/greasy skin
Hyperhidrosis: excessive foot sweating
Tinea Nigra Epidemiology
Temperate climates
Younger patients
Females
Palms and soles
Causes of Superficial Tineas
Trichophyton, Microsporum, Epidermophyton
Anthropophilic fungi: person-to-person (most
common)
Zoophilic fungi: animal-to-person
Geophilic fungi: soil-to-person
Manifestations of Fungal Skin
Infections
Anthropophilic: little inflammation
From pets or soil: Acutely inflamed; allergies
to fungal antigens
Manifestations: Tinea Pedis
3 forms
Intertriginous: macerated, boggy, white, thick,
odorous, pruritic between toes
Acute vesicular: inflammation, fissuring; 2˚
bacterial infections; odorous, pruritic;
extreme pain in walking
Moccasin: chronic, nonvesicular, over plantar
foot
T. Pedis
Manifestation: Tinea Pedis
Flares in the summer; abates in winter
May cause tinea manuum: “one-hand, two-foot
disease”; Hands are dry, red, scaly
Manifestations: Tinea Corporis
Glabrous skin (smooth and bare)
Not on scalp, feet, hands, groin, ears, face
Oval, scaly patch with inflamed border
Centrally, skin often appears lighter or normal;
thus, the lesion appears to be a ring circling
beneath the skin surface
15-20 lesions over the body
Lesions coalesce: polycyclic appearance
T. Corporis Presentations
T. Corporis Presentations
T. Corporis Presentations
T. Corporis Presentations
Manifestations: Tinea Cruris
Sharply defined lesions
Inflamed borders, reddish-brown centers
Begins in groin skinfolds
Spreads to perineum, thighs, buttocks
Intense pruritus
Sweating causes overt pain
2˚ bacterial infection possible
T. Cruris Presentations
T. Cruris Presentations
Manifestations: Tinea Capitis
Circular patch of scaly skin
Dry, noninflammatory dermatosis
Patchy areas of hair loss
Crown, parietal areas
“Black dots”: hairs broken off at the scalp
Kerion or favus: both worse involvement
T. Capitis Presentation
Manifestations: Other Tineas
Unguium: opaque, yellow nails; thickened;
brittle, crumbled; nail lifts and may be lost
Versicolor: lesions darken in winter, lighten in
summer
Nigra: black, brown discoloration on palms,
lesions may coalesce; no scaling, nonpruritic,
painless
T. Unguium Presentation
T. Versicolor Presentations
Tinea Incognito
Inappropriate assumption that lesions are
allergenic in etiology
Treatment of the lesion with steroids
Steroid decreases inflammatory barriers,
allowing spread to accelerate
As spread accelerates, patient increases use of
steroids
Tinea Incognito
Tinea Treatment Guidelines
Be sure lesions are fungal
Check for other medications or medical conditions
causing lesions
Ointments last longer than creams
Aerosols easy to use on skin and in shoes
Only self treat: pedis, cruris, corporis
Continue for full course of therapy
Tinea Pedis Treatment
If topicals ineffective, orals may be necessary
2˚ bacterial infections may require antibiotics
May also need antiperspirants
Recurs in 70% of patients
Tinea Corporis Treatment
If condition does not clear, may be
Psoriasis
Eczema
Medication-induced eruptions
More severe fungal pathogens
Tinea Cruris Treatment
Responds more readily to therapy than tinea
pedis or tinea corporis
Treatment times are shorter
Tineas Requiring Referral
Tinea capitis: Topical medications do not
penetrate follicles
Tinea Unguium: Forget Fungi-Nail; requires
systemic therapy
Tinea Versicolor: Requires Rx meds
Tinea Nigra: Differentiate from other
pigmentation such as melanoma: requires Rx
meds
Self-Care
Only pedis, corporis, cruris
Not for nails, scalp, vaginal yeast infections, diaper rash
Supervise children
External use only
Keep from eyes
Clean skin with mild soap first
Apply morning and night
Therapeutic Choices: Classify By
Cure Rates/Dosing
First Generation: Longest cure rates
Second Generation: Shorter cure rates
Third Generation: Shortest cure rates for
tinea pedis coupled with once-daily dosing
First Generation (Oldest)
First Generation: use down to 2 years
Undecylenic acid: around pre-1970s
Tolnaftate: OTC in 1971
Miconazole: OTC in 1982
Clotrimazole: OTC in 1989
Use 4 weeks for corporis & pedis, 2 weeks for
cruris
Age limit is 2 years
Clotrimazole
Occasional burning, stinging, peeling, other
minor local reactions
Clotrimazole: Lotrimin AF Creams
Clotrimazole Products: Lotrimin AF
for Her and Fungi Cure Intensive
Miconazole Nitrate
Occasional burning and irritation
Otherwise, safe and effective ingredient
Miconazole Products: Micatin
Cream
Miconazole Products: Neosporin
AF, Desenex Powder, Cruex Spray
Miconazole Products: Lotrimin AF
Powder and Aerosol Powders
Lotrimin AF Differences
Note that some dosage forms of Lotrimin AF are
clotrimazole, where others are miconazole
Evidently, clotrimazole cannot be produced in
any aerosol form
Tolnaftate
Irritation on excoriated skin
Only ingredient proven to prevent recurrences: apply to
dry feet 1-2 times daily, at start of spring/summer
Tolnaftate Products: Tinactins
Tinea pedis spray
Jock Itch spray
Tolnaftate Products: Tinactins
Tolnaftate Products: Lamisil
Defense
Tolnaftate Products: Fungi Cure
Gel
Undecylenic Acid
Odor slightly unpleasant
Fungi Cure Liquid, Fungi Nail
Second Generation
Newer Meds (Post-2000): Only 12 and over
Terbinafine: 1999
Butenafine: 2001
Terbinafine
Lamisil AT Cream, Spray Pump, Solution
Only for those aged 12 and over
Cures pedis between toes if used BID for 1 week
Only Lamisil AT Cream has an indication for pedis on
bottom/sides of feet: used twice daily for 2 weeks
Cures cruris and corporis used once daily for 1 week
Lamisil AT Products
Butenafine
Lotrimin Ultra Cream
Only for those aged 12 and over
Cures pedis between toes if used BID for 1 week
OR once daily for 4 weeks
Efficacy on bottom and sides of feet unknown
Cures cruris and corporis used once daily for 2
weeks
Lotrimin Ultra
Tinea pedis box
Jock Itch box
Third generation
Newest Option: Lamisil AT Gel (terbinafine)
Innovative
One large advantage that will cause it to
rapidly become the nonprescription standard
for tinea pedis treatment
Requires only one application daily to achieve
cure for tinea pedis between the toes in only one
week
Age cut-off is still 12 years
Lamisil AT Gel
Lamisil AT Gel
Ability of patient to treat only once daily will
increase adherence to dosage regimen and
increase the chances of full cure
Efficacy on bottom or sides of feet is unknown
Deceptive Product
Fungi Nail: Only 25% undecylenic acid; cannot
cure fungal nails; many consumers are misled
Deceptive Product
Dr. Scholl’s Fungal Nail: Contains tolnaftate
cream, revitalizer cream, a brush and file; cannot
cure fungal nails and also misleads consumers
Deceptive Product
Blue Star Ointment: Recommended for tinea
cruris, pedis, and corporis; camphor 1.24%,
methyl salicylate, salicylic acid; junk product;
extreme pain if applied to broken skin
Prevention of Pedis
Keep feet clean & dry
Dry thoroughly after bathing; use antifungal powder
Go barefoot whenever possible
Wear open sandals
Use thongs when in communal bathing or showering
facilities
Change shoes/socks daily
Prevention of Pedis
Never share footwear
See physician immediately if toenails infected
Use preventive tolnaftate if recurrent
If present elsewhere, don’t use same towel to dry the
feet
Wear several different shoes so they can dry
Wear cotton socks
Prevention of Corporis
Wash/dry with different cloths than those used to
wash/dry the feet
Never play with strange cats/dogs
Avoid contact with infected people
Lose weight: less intertriginous skin
Dry thoroughly after bathing, especially intertriginous
skin (e.g., beneath breasts)
Never garden in bare feet or knees
Prevention of Cruris
Lose weight
Wash and dry groin with different towels/wash
cloths
Avoid sexual contact with infected individuals
Wear underclothes that allow evaporation