L2 Fungus Acne Bugs Flashcards
Tinia Capitis : Gray Patch
scaly demarkated patch that spreads centrifugally;
hairs break off 2.3 mm above skin and becomes silver
endemic form, due to pets
Dermatophyte: Tinea capitis
- Trichophyton sp. (T. Tonsurans (USA))
- Microsporum sp. (M. Canis (EUrope))
Epidem: 3-14 yo, AA, bad hygiene, overcrowding, low soc.econ, asym. carriers
3 types: Gray patch, blac dot*, Flavus
Fomite transmission
Black Dot Tinea Capitis
hair breaks off at the skin so the black dot is hair under skin
most common in US
Flavus Tinea Capitis
rare
hairy follicular inflammation causing crusting
Tinia Capitis Dx eval
- KOH prep (scraping from affected scalp, add KOH and look under mscope)
- Wood’s light (gray fluoresces a greenish culture; flavus blue; black dot not fluorescent)
- culture (4-6 wks)
Tinea Capitis DDx
Seborrheic Dermatitis Contact dermatisis pustular/plaque psoriasis Atopic dermatits alopecia areata trichotillomania
Tinea Capitis Tx
Griseofulvin 6-12 wks (tx for microsporum)
Terbinafine 2-4 wks (tx if TRICHOPHYTON (USA))
Itraconazole (4-6 wks) and fluconazole (3-6 wks) or pulse therapy(8-12)
[Cant use ketocanazole with above]
Pets; carriers don’t need oral AF, can tx with blue selsum shampoo
Need extended f/u
Tinea Corporis
Etiology: T. Rubrum* (see slide)
Epi: occlusive clothing, humidity exacerbate (wrestlers); fomites/person to person
- pruritic (itchy), annular (round), erythematous plaque with central clearing and advancing border (border usually raised)
women shaving legs - worse with steroid topicals
Dx Eval and DDx
KOH prep
Culture
DDx: Erythema annulare centrifugum, nummular eczema, psoriasis, tinea versicolor
Tinea corporis (ring worm) Tx:
- Topical angifungals (-azole)
- systemic tx in special cases (terbinafine, fluconazole, itraconazole) [no ketocanazole]
- sports restrictions (for 10-15 days after tx)
Tinea cruris (groin genital area)
- T. Rubum* and E.floccosum*
- 2nd most common dermatophytosis
m>f, adults, direct contact, fomites or auto-inoculation
occlusive clothing, humidity
Tinea Cruris
Spares the scrotum; helps distinguish TC from a yeast infection or Candida in same area
- well-marginated, annular PLAQUE with scaly raised border
- from inguinal fold to inner thigh
- pruritis and pain
Tinia Cruris Dx eval and DDx and Tx
- KOH prep
- culture
DDx:
erythrasma, cutaneous candidiasis, intertrigo, contact derm, psoriasis, seborrheic derm, Lichen simplex chronicus, folliculitis
Tx: topical antifungals, resistant cases: oral griseofulvin (AF), tx concomitant tinea pedis and/or onychomycosis, daily talcum powder;
avoid hot baths and wear loose clothes
Tinea Pedis
T. rubrum *
Epi: MOST COMMON dermatophytosis, 10%, Risk: occlusive shoes, communal baths/pools
4 types: interdigital * (athlete’s foot) - at risk for 2ndary bact infection
Chronic Hyperkeratotic (Moccasin) - chronic
Vesiculolullous - hard vessicles
Acute Ulcerative - severe where you have bacterial inf and possible septic infection
Tinea Pedia Dx Eval, DDx, and Tx
Dx: KOH
DDx: Eczema, psoriasis, BACTERIAL COINFECTION (always look for with TP), interdigital erythrasma, dyshidrosis, contact derm
Tx: topical AF cream x 4 wks
chronic disease (oral tx for moccasin TP)
Burow’s wet dressings for vesiculation or maceration, 20 min BID-TID
Tx 2ndary infections
Foot powder, tx of shoes, proper shoes
Yeast Infections: Tinea VERSICOLOR
Malassezia sp. (M. Furfur, M. Globosa)
Epid: hot humid weather, 2-8% in US, no age, sex, race, more visible in dark skin,
Risk: excess sweat, hyperhidrosis, OCP, sys steroids, Cushings disease, immunodepression, malnourished
Clin: hypo/hyper-pigmented, salmon or erythematous macules
Tinea Versicolor Dx, DDx and Tx
Dx: KOH (potassium hydroxide)
Wood’s Lamp: yellow to yellow-green fluorescence in 1/3
DDx: Pityriasis alba/rosea, seborrheic derm, dermatophyte inf’s, erythrasma, vitiligo, psoriasis, 2ndary syphilis
Tx: 1) Topical - Azole AF’s (ketocanazole topical ok) x 2 wks
- Selenium sulfide (lot,shamp,foam) x 1 wk
2) Systemic - Oral azole AFs
- Oral terbinafine and griseofulvin NOT effective
Recurrence is common - can go on maint tx - use oral or topical 1/mo
Acne Vulgaris
most common in US, teens (10-20% adults)
Risk: friction/trauma, comedogenic topicals, meds (glucocorticoids, OCP, lithium, INH, phenytoin, phenobarbital), genetic, PCOS (polycystic ovarian syndrome)
Acne vulgaris definition
chronic inflam disease of the pilosebaceous unit, self-limited
- increased sebum prod’n by seb glands
- hyperkeratinization of the follicle
- colonization of the follicle (Propionibacterium acnes)
- Inflammatory rxn
Acne Vulgaris types
Comedones (closed: plugged with sebum and keratin; open at top: blackhead)
Papules, pustules (inflammation surrounds follicles), nodules (inflammation in and around papules?) [All three have redness]
Acne V DDx and Dx
DDx: Sebaceous hyperplasia
acne rosacea
perioral derm
folliculitis
Dx: mild - less than 1/2 face, usu comodones in T zone, no nodules, poss inflammation
moderate - more than 1/2 face and poss back, maybe some nodules
severe - severe nodules, lots of scarring
Acne V Tx
try tx for min of 8 weeks
Topical retinoids: Trerinoin (Retian-A) (C), Adapalene (Differin)(C), Tazarotene (Tazorac):Category X pregnancy
Prevent formation and reduce comedone, anti-inf
Indications - monotherapy for non-inflamm acne (open/closed comedones)
- combo therapy with ABs for inflamm acne
Topical ABs: Clindamycin, Erythromycin
Indications: mild-moderate inflamm or mixed acne
Use in combo with benzoyl peroxide to prevent resistance (?)
More effective when in combo with retinoids
Acne V Tx other topicals and oral ABs
Other topicals:
Alelaic acid (mix antimicrobial and anticomedonal; mild-moderate inflam or mixed acne)
Dapsone (AB but MOA? mode of action? is inhibiting inflammation)
Benzoyl peroxide (bactericidal: mild-moderate mixed acne, as combo)
Salicylic acid (anticomedonal)
Oral ABs (8 wks): Doxycycline, Minocyline, Erythromycin, Tetracycline Moderate-severe; add benzoyl peroxide; once contolled, maintain with topical retinoids
Acne V Tx other
- OCP (oral contraceptives): Ortho Tri-Cyclen, Yaz, Estrostep
2nd line, inf and non-inf; (estrogen has anti androgen properties) - Spironolactone (Aldactone):
androgen receptor antagonist; 2nd/3rd line or alternative to isotretinoin - Oral isotretinoin (acutane): for severe recalcitrant (uncooperative) or less severe treatment resistant
40% long term remission, 40% need topicals or ABs, 20% re-tx
Monitor: CBC, Lipids, Liver enzymes (acute hepatitis risk)
Side-eff: depression, suicide, HA, dry skin and MM? multiple myoloma, GI upset
iPLEDGE program to prevent pregnancy - strict tests - Other: clean BID, h2o based skin products, picking
4 signs of skin
Distribution
Shape
Border
Pigmenation
Acne Rosacea general
More in whites, f>m, in 30+ yo
Immune disfx, inflam rxn to cutaneous organisms, UV, Vascular
Definition: Erythema of central face, persisting for months of more
Distribution: nose, cheeks, chin, forehead
Subtypes: Erythematotelangiectatic, papulopustular, phymatous, ocular
Clin: - flushing, papules, pustules, telangiectasias
-facial burning, edema, plaques, dry appearance, phyma, peripheral flushing, ocular manifestation
-flares of exacerbation and inactivity
-Triggers: temp, sun, wind, hot drinks, excercise, spices, ETOH, menapausal flushing, meds - flushing, cosmetics, emotions
Rosacea DDx
Acne V SLE (lupus) Polymyositis Sarcoidosis Photoderamtitis Drug eruptions Perioral derm
Rosacea Tx
Dx’d by inspection
Topicals: 1st line for mild papulopustular rosacea
- Metrogel (Metronidazole) FDA *
- Azelaic Acid (Azelex) FDA *
- Sulfacetamide / sulfur cream
-benzoyl peroxide/clindamycin or benz per/erythromycin (not as effect)
- topical brimonidine (vasoconstrictive alpha-2 adrenergic rec agonist)*
(FDA for persistent facial erythema of rosacea, 2013)
Pediculosis Capitis
Head Lice
4-6 wk incubation
often asymptomatic
pruritis - itching is allergic rxn to salive
Eggs hatch after 10 days - some tx lice some kills eggs, some kill both
Dx: Visual inspection
Nits fluoresce pale blue with Wood’s light
Pediculosis Capitis DDx and Tx
Head lice
DDx: hair casts, seborrheic derm, exzema, psoriasis, hair spray residue, delusions of parasitosis
Tx:Topical pediculicies! (Perythroids, malathion, spinosad, top ivermectin)
!! DON”T use LINDANE!!
Wet combing
Oral: ivermectin, TMP-SMX (combo with Permethrin)
Scabies
host-specific mite (Sarcoptes scabeie)
live 3-days away from host
female mite excavates a burrow in the stratum corneum in which she lays 2-3/day for 30 days
Eggs hatch in 10 days - !!!Do re-tx in 10 days!!!
All age/race/gender
Transmission?
Scabies clin and dx
initial lesion
BURROW IS PATHOGENIC (and diagnostic of scabies)
Back and head often spared
Pruritis, and some urticaria
dx: visualization of burrow
microscopic ID of mite, eggs or fecal pellets
Scabies DDx
Atopic derm Dyshidrotic eczema Contact derm Insect bite rxn Derm herpertiformis Psoriasis Delusions of parasitosis
Scabies Tx
1) Scabicide: initial tx +2nd application 1 wk later
- PERMETHRIN 5% cream
-Lindane
-Ivermectin orally
2) Fomite control
3) Tx household contacts
POSTSCABETIC Itch - itch for wks after tx
Oral antihistamines and emollients/cleaning
Bee sting management
generalized systemic rxin in .4-3% (not anaphylaxis)
Mngt: cleanse, ice, anesthetic injection
- oral or parenteral diphenhydramine for urticaria/pruritis
- epinephrine for anaphilaxis
