Fungal infections Flashcards
What are fungal infections?
Infection that thrives in moist, humid, warm environments
More prevalent in sub/tropical areas.
What causes skin infections
Dermatophytes (tinea): fungus affecting stratum cornea of epidermis and appendages. Contagious, classified on area.
- microsporum, epidermophyton, and trichophyton.
Yeasts: candida or malassezia
Signs and symptoms of tinea pedis (athletes foot)
Located on feet
Itchy, flaky, redness, moist
May have an unpleasant odour
Signs and symptoms of tinea corporis
Located on trunk, legs, arms, neck
Pink or red scaly lesion, slightly elevated, well defined border
Active outer edge and clear centre
Mild to moderate itch
Singular, numerous, or overlapping lesions
Chronic form in skin folds
Signs and symptoms of tinea unguium
Located on nails
Early signs: distal and lateral yellow/white discolouration
Later: nail thickens, plate lifts off bed
Nail becomes brittle and crumbles away/falls off
Signs and symptoms of tinea capitis
Located on head
Asymptomatic or slightly itchy
Red and scaly, broken hair
Inflamed / pus-filled
In severe, fungal abscess may occur
Signs and symptoms of tinea cruris
Located on the groin
Scaly red margin from groin to inner thighs
Defined, raised patches w/ small pustules
Clear centre
Mildly itchy
Signs and symptoms of tinea manuum
Located on hands
Scaly, annular (round/circular) rash w/ active border
Signs and symptoms of pityriasis versicolour
Commonly on upper trunk.
Discoloured patches (light-brown, patchy hypopigmentation)
Superficial light scaling if scratched
Normally asymptomatic, sometimes mild itch
No sun: red-brown circle lesions
Sun: infected lesions do not tan
Not infectious but is recurrent
Signs and symptoms of oral candidiasis
White, creamy patches in mouth, easily wiped off
Red and sore under white coat
Infants- uncomfortable sucking
Adults- taste changes
Signs and symptoms of vaginal candidiasis
Thick, white discharge
Non-offensive odour
Itch or soreness
Painful sexual intercourse
External dysuria
Signs and symptoms of napkin candidiasis
Skin folds
Clusters of red papules and plaques
Demarcated lesions
Topical treatment of fungal infections
Topical imidazoles (ketoconazole, miconazole) - creams, lotions, solutions. Continue for 14 days after symptoms resolve.
Terbinafine (Lamisil) - Cream, gel, solution. Rapid, once daily application, short use- 1 week, continue for 2-3 days after symptoms resolve.
Tolnaftate (tinaderm) - spray, powder. less effective.
Topical treatment for tinea unguium
Amorolfine 5% nail lacquer (Loceryl)
- once to twice weekly for 6 months fingers, 9-12 mths for toes
- continue until nails are cured and regrown
Bifonazole 1% and Urea 40% (Canestan fungal nail)
- Intended for mild-moderate infection.
- Phase 1: weeks 1-3
keratinolytic agent that softens impacted nail to leave non-infected part intact. apply od for 2-3 wks.
Explain systemic treatment of tinea
Indicated for nails, hairy areas, palms, soles.
If widespread
If unresponsive to topical.
If recurrent or previously treated w/ corticosteroids
Must confirm w/ microscopy and culture
Expensive and serious ADRs
Tinea systemic treatment
Oral terbinafine (250mg) - od for 2-6weeks, up to 12 weeks. First line.
Fluconazole - 150mg once weekly for 4 weeks OR 50mg od for 2-6 weeks. Higher dose for nails, up to 52 weeks. Use if resistant to topical.
Itraconazole - 200mg bd after food for 1 week
3-4 mths toes
2 mths fingers
Use if terbinafine not tolerated. Monitor liver function.
Griseofulvin - feet/nails - 1g od until regrown, other areas - 500mg od 8-12weeks
Less effective, less tolerated, long duration.
Pityriasis versicolor treatment
Topical antifungals- econazole 1% solution, ketaconazole 2%, micaonazole 2% (dose depending on brand)
Anti-infectives - selenium sulfide 2.5% shampoo.
Fluconazole 400mg - if topical unresponsive. Not PBS approved.
Itraconazole 200mg - prophylactic therapy.
Oral candidiasis treatment
Miconazole 2% gel:
birth-2= 1.25ml
>2 yrs= 2.5ml
use 4 times daily after food for 7-14 days.
Nystatin oral suspension - 1ml in mouth swallowed 4 times daily after food for 7-14 days
Amphotericin lozenges - 1 4 times daily after food for 7-14 days
Continue treatment for several days after symptoms resolved
Vulvo vaginal candidiasis treatment
Intravaginal antifungals - clotrimazole, miconazole, nystatin
Oral fluconazole - 150mg single dose. not for pregnant.
Boric acid 600mg - isolated w/ C.glabrata
Male partner management
Not necessary = not sexually transmitted
Symptomatic = swab and treat
relieve discomfort w/ imidazole cream w/ 1% hydrocortisone
Napkin candidiasis treatment
Topical corticosteroids:
hydrocortsione 1%
cause skin irritation
Used for 3-5 days for inflammation and discomfort
Severe:
methylprednisolone aceponate 0.1%
triamcinolone acetonide 0.02%
Topical antifungals +/- zinc oxide:
miconazole, clotrimazole, nystatin
treat for 14 days after symptoms resolve
Referral of fungal infections
Unsure diagnosis
Severe
Unresponsive
Recurrent/chronic episodes
Lifestyle changes for fungal infections
Keep skin dry and clean
Use separate towel for infected areas to prevent spread
Wear breathable/natural fabrics
Avoid wearing tight clothes
Don’t share clothes, towels, combs, hats.
