14 - Yeasts And Fungal Flashcards
Yeast and fungal infections?
Candida
Tinea versicolor
Dermatophytosis
Sporotricosis
When does candida become pathogenic?
Damage to stratum corneum or pre-existing condition/disease
- pregnancy
- sugar aids
- contraceptives
- abx therapy
- topical steroids
- immunosuppression
Morphology of candida?
- mouth
Oral (thrush)
- white adherent plaques, erosions on tongue
Angular chelitis
- erosion, flaking at corners of mouth
Morphology of candida
- genital
Vulvovaginitis
- thick, white discharge
- erosions satellite lesions
- pruritic, tender edematous
Intertriginous (skin folds)
- diaper dermatitis
- erosion interdigitalis blasto
- inframammory
- balanitis
- paronychia (nail folds)
Presentation of paronychia candida?
Erythema
Maceration and erosion
Papule and satellite pustules
Dx of candida?
Clinical
- suspect -> tx
KOH prep
- pseudohyphae w budding spores
Tx of vaginal candida?
Oral DOC
- fluconazole (diflucan)
- not for preggos
Topical - azoles or nystatin
- safe in pregnancy
- clotrimazole and miconazole (MC)
- creams, vaginal tabs, suppositories etc
- 3 day regime
Txt of oral candida?
Fluconazole
Clotrimazole
Ketoconazole
What is tinea/pityriasis versicolor?
Over growth of yeasts
- pityrosporum orbiculare and P. Ovale
- normal skin flora
Seen in hot, humid climates
- causes yeasts to change
Morphology of tinea/pityriasis versicolor
Individual lesions and distrobution are highly characteristic
Begin
- multiple small circular macule of various colors (white, brown, pink)
- enlarge rapidly
- superficial flaking
- typically turns darker in LPP and lighter in DPP
Clinical manifestation of tinea/pityriasis versicolor?
Asymptomatic (usually)
- may itch w inflammation
Concern is appearance
Dx for tinea/pityriasis versicolor?
Powdery scale upon scraping
KOH
- numerous short, broad hypahe and clusters of budding cells
- spaghetti and meatballs
- bats and balls
Woods light
- pale yellow to white fluorescence
Distribution of tinea/pityriasis versicolor?
MC site
- mid chest and upper back
Antecubital fossa
Neck
Extensive eruptions
- upper arms and lower face
Face lesions ore MC in kids
Tx for tinea/pityriasis versicolor
Topical agents
- ketaconazole (nizoral) shampoo
- selenium sulfide suspension 2.5%
Oral agents
- ketoconazole (nizoral)
- itraconazole
- Fluconazole (diflucan)
Prevent recurrences
- ketaconazole shampoo AAA weekly
Where is dermatophytes (tinea) commonly found
On anyone
MC in hot, humid areas
Etiology of dermatophytes (tinea)
Infects and survives only on dead keratin (stratum corneum, nails, hair)
Sources: animals, soil, humans
Inhabits the skin w/o infection
Dermatophytes normal flora?
No
Distribution of dermatophytes (tinea)
Tinea capitis - scalp
Tinea pedis - feet
Tinea corporis - trunk, face, limbs
Morphology of dermatophytes (tinea)
Ringed annular lesion
Raised scaly borders
Expanding central clearing
Normally - papules/plaques occasionally - pustules - vesicles - erythema w flaking
Workup for dermatophytes?
Dermatophytosis (not clinical dx)
KOH - use active border, branching hyphae
DTM culture (turns red)
Woods light
- no fluorescence except w tinea versicolor
Tinea corporis is aka?
Ring worm
Tx for ringworm?
Superficial lesions (use topicals)
- clotrimazole
- miconazole
- ketaconazole
- terbinifine
Extensive/deep (oral agent)
- fluconazole
- terbinafine
- itraconazole
- griseofulvin
- ketoconazole
Tinea pedis is aka?
Athletes foot
Tx for tinea pedis?
Topicals, interdigital
- terbinafine
- clotrimazole
Oral if moccasin type
- terbinafine
- itraconazole
- fluconazole
Tinea manuus?
Hand infection
- 1 hand 2 feet
More common in men
Tx like tinea pedis
Tinea barbae tx
Oral agents
What is tinea incognito?
Fungal infection tx w topical steroids
MC on groin, face and dorsal hands
Problem w tinea incognito?
Steroids alter characteristics of fungi
- marginal scaling absent
- diffuse erythema, scale, pustules
- absence of boarder
What does the steroid do to dermatophytes?
Inflammation gets better while fungus flourishes
Tinea cruris is aka?
Jock itch
Diagnosis of tinea cruris?
No fluorescence w woods lamp
Txt for tinea cruris?
Keep clean and dry
Meds that cover fungus and candida
Topical
- clotrimazole
- miconazole
Oral agents for extensive infection
Presentation of tinea capitis?
Ranges from
- mild scaling and broken hairs
- extensive alopecia
MC Pattern of infection w tinea capitis?
Black dot type
- hairs broken at orifice
Dx of tinea capitis?
Sterile toothbrush rubbed over affected scalp -> inoculate fungal culture medium
Txt for tinea capitus?
Systemic oral agents
Kids
- griseofulvin
Adults
- griseofulvin (DOC)
- terbinafine
- itraconazole
What is kerion?
Inflammatory tinea capitis
- alopecia
- adenopathy
- fever
KOH may be neg due to local destruction of fungal structures
Kerion tx?
Tx w oral antifungal
- griseofulvin
- terbinafine
- oral steroid (maybe)
What is onychomycosis?
Fungal infection of the nails
MC and least serious deep fungal infection?
Sporotrichosis
What causes sporotrichosis?
Saprphytic fungus
- inoculation by trauma
This is the rose thorn disease from ID
- MC found in florists, farmers and hunters
Diagnosis of sporotrichosis?
Punch or excision biopsy
- 1/2 for special stains/microscopic exam
- 1/2 for culture
Morphology and distribution for sporotrichosis?
Initial lesion - painless papule/nodule/ulcer
Lesions increase in number over weeks
Lymphatic pattern - sporotrichoid
LAD common
MC site of sporotrichosis?
Finger
Sporotrichosis tx?
Itraconzole (sporanox)
- q 3-6 months
Classic (older) txt
- potassium iodide until clear then 1 month more
- bad SE and doesnt work well
How does the lion greet the other animals in the field?
Pleased to eat you!
