Dermatology 3 Flashcards

1
Q

Which bacteria account for a majority of the skin infections?

A

staph aureus and A beta hemoltic strep, S. aureus invades skin and causes impetigo, folliculitis, cellulitis and furuncles; strep invade traumatic lesions and cause impetigo, erysipelas, cellulitis and lymphangitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Impetigo

A

common, contagious, superficial skin infection that is produced by strep, staph, or combo; bullous and nonbullous impetigo, both begin as vesicles w/ very thin, fragile roof consisting only of stratum corneum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What may follow impetigo

A

poststrep gn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Bullous impetigo

A

epidermolytic toxin, causes intraepidermal cleavage below or within the stratum granulosum, common in infants/children, 1+ vesicles enlarge-> bulla, clear and cloudy, thin flat, honey colored crust, disclosed+ bright red, inflamed, moist oozing base, tinea like scaling

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Nonbullous impetigo

A

small vesicle or papule that ruptures to expose a red moist base, sequence of events- bac-> carriage on skin-> infection post trauma; honey-yellow to brown, firmly adherent crust accumulates as the lesion extends,

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Nonbullous impetigo lesions

A

satellite lesions appear beyond periphery, usually appear on nose, mouth, and limbs, untreated lesions may last weeks, heal without scarring

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Treatment of impetigo

A

prevent w/ mupirocin or triple abx TID, pt w/ recurrent impeigo should test for S. aureus, nares most common site, treat carriers, isolate until tx, oral abx- dicloxacillin, cephalosporin, mupirocin ointment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Cellulitis

A

an infection of dermis and subcutaneous tissue, no clear distinction between infected and uninfected skin, H. influenzae is most common etiologic agent in children

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Erysipelas

A

acute inflammatory cellulitis w/ lymphatic involvement, infected area is raised, a distinct demarcation in involved and normal skin, lower legs, face and ears are most commonly involved, also called st. anthony’s fire due to its bright red intensity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Treatment of cellulitis

A

dicloxacillin or a cephalosporin, vancomycin in pts allergic to penicillin, cefotaxime and ceftriaxone are effective, rifampin prophylaxis for fam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

H. Influenzae cellulitis treatment

A

must be prompt before gas formation/purulent collections, requires surgical drainage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Folliculitis

A

inflammation of follicle, infection, chemical, or physical injury, superficial folliculitis is confined to upper part of hair follicle, manifests as painless, tender pusutles that heal w/out scarring; deeper lesions scar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Types of folliculitis that are painless or tender pustules

A

Staph, pseudofolliculitis barbae, candidiasis, acne, keratosis pilaris

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Types of folliculitis that are painful

A

furuncle, carbuncle, cysic acne, pseudomonas folliculitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Pseudofolliculitis barbae

A

foreign body to hair, cheeks and neck in individuals who have tight curls that become ingrown, blacks, tender, red papule or pusule occurs at point of entry and remains until hair is removed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Treatment of pseudofolliculitis barbae

A

permanent hair removal with laser assisted hair removal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Sycosis barbae

A

sycosis implies follicular inflammation of the entire depth of follicle, caused by S. aureus or dermatophyte fungi, men who begin shaving, fungal deep infection, bacterial-discrete papules, similar to p. barbae but more inflammation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Sycosis barbae treatment

A

localized infection can be treated with mupirocin, extensive treated w/ abx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Furuncle

A

walled-off collection of pus, painful, firm or fluctuant mass, prone in areas of friction, s. aureus, begins as deep, tender, firm, red papule that enlarges rapidly, may have fever, malaise, chills

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Treatment of furuncle/carbuncle

A

warm compresses, localization and pointing of abscess,, incision, drainagge, packing, don’t drain until skin is thinned and mass is soft, culture and gram stain, abx, r/o diabetes in recurrent infection

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Pseudomonas folliculitis

A

infects warm, moist areas, whirlpool, hot tub use, few to >50 pruritic, round urticarial plaques w/ central papule or pustule on all surfaces, self-limiting, 5% acitec acid wet compresses, silvadene cream, cipro 500mg-750 mg BID

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Verruca vulgaris

A

Benign epidermal growth caused by HPVs, more than 100 different types discovered each year, transmitted by touch, sites of trauma, swimming pools, warts obscure normal skin lines, begin smooth, flesh colored-> dome shaped, gray

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Verruca vulgaris treatment

A

requires several tx sessions, topical salicylic acid prep, liquid N, light electrocautery, blunt dissection for resistant/ very large lesions, cryotherapy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Cryotherapy

A

spray liquid N so 1-2 mm zone of frozen tissue is created and maintained for 5 secs, allow to thaw and repeat once or twice to increase cure rates, small blisters and sometimes bleeding appears, may repeat 2-4 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Verruca plana (flat warts)

A

Pink, light brown or light yellow, flat topped papule .1-.5 cm, common on forehead, mouth, back of hands, shaved areas, resistant to tx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Treatment of verruca plana

A

aldara cream, liquid N or light electrocautery, 5-fluorouracil applied 1-2x for 3-5 weeks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Plantar warts

A

on soles, pt refer to many warts as plantar, occur at point of max pressure, head of metatarsal bones or heels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Corns can be distinguished from plantar warts by

A

paring the callus, corns have hard, painful, well demarcated, translucent central core, warts have central black dots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Black heel

A

horizontally arranged clusters of blue-black dots

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Treatment of plantar warts

A

don’t treat unless painless, debride hyperkeratotic tissue, salicylic acid liquid, blunt dissection, aldara cream, cantharidin mixture w/podophyllin and salicylic acid, lasar treatment, cryosurgery

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Molluscum contagiosum

A

poxvirus infcn, discrete 2-5 mm slightly umbilicated, flesh colored dome shaped papules, spreads by autoinoculation, touching or scratching, face, trunk, axillae, and extremities common sites, most are self limiting, heal 6-9 months

32
Q

molluscum contagiosum treatment

A

Curettage- destroy top part of skin, cryosurgery, cantharidin, extract from blister beetle is effective, not > 20 lesions in one visit, diff in children, aldara cream, retin A, salicylic cream TCA, laser tx

33
Q

Herpes Simplex

A

Caused by HSV1/2, HSV1- oral infections, HSV2- genital, both produce identical pattern, genital recurrence are 6x more frequent, primary infection-virus established in nerve ganglion, secondary- recurrent at same site

34
Q

Primary infection of HSV

A

asymptomatic and can be detected by elevated igG ab titer, spread via resp droplet, direct contact or virus containing fluid, saliva or cervical secretions, uniform vesicles uniform size- 2-4 weeks, virus replicates at site

35
Q

Recurrent infection HSV

A

local trauma, systemic change, prodromal sx- itching and burning 2-24 hrs (can prevent if treated), 12 hrs- vesicles and papules may appear

36
Q

Treatment of HSV

A

acyclovir cream, denavir cream, abreva, oral antiviral plus topical steroid, oral antivirals- acyclovir, valtrex, famvir

37
Q

Cutaneous herpes simplex

A

herpetic whitlow- fingers, peds or females w/genital; herpes gladiatorum- waist, skin-skin contact, wrestlers; herpes on buttocks- women, herpes simplex of the trunk

38
Q

Varicella

A

chicken pox, highly contagious, peak in march, april and may, airborne or vesicular fluid, contagious 2 days before onset until all lesions have crusted, confers life long immunity, latent in ganglia on neuraxis

39
Q

clinical course of varicella

A

incubation- 9-21 days, prodromal- fever, HA, malaise, eruptive phase- lesions up to 4 days, crusting by 6 d, 2-4 mm red papule, develop irregular outline, a thin walled clear vesicle appear on surface, begins on trunk-> face

40
Q

Congenital or neonatal varicella

A

1st tri- limb hypoplasia, chorioretinitis, cortical atrophy, scars; 2nd tri- undetected fetal chickenpox, near birth- if mom has 2-3 weeks before delivery, fetus born w/ develop lesions 1-4 days after birth, mortality 20%, give ZIG or VZIG or gamma globulin

41
Q

Lab diagnosis of varicella

A

culture, difficult due to labile virus, serologic testing- presence of IgG- past exposure, IgM- recent infection, Tzanck smear- rapid diagnosis, multinucleated giant cells

42
Q

Treatment of varicella

A

vaccine- live attenuated, recommended for all above 12 months or older, prevented chicken pox in 85%, 97% against severe, acyclovir, or Foscarnet if resistant

43
Q

Herpes zoster

A

shingles, cutaneous viral infection around dermatomes, 10-20% risk, inc w/ age as T-cell immunity to virus wanes, zoster results from reactivation of varicella virus in dorsal root ganglia

44
Q

Clinical presentation

A

preeruptive pain, itching, burning, generally localized to dermatome, precedes eruption by 4-5 days, may simulate pleurisy, MI, abd disease, HA, may have prodromal sx

45
Q

Zoster sine herpete

A

segmental neuralgia w/out any cutaneous eruption

46
Q

Clinical features of shingles

A

eruptive- red swollen plaques, various sizes, spreads to dermatome, clusters w/ red base w/ purulent fluid 3-4 days, thoracic region, does not confer immunity, pain is neuropathic

47
Q

Complications of shingles

A

pain persisting, can persists for m-y, encephalitis, immune mediated rather than result of virus

48
Q

Treatment of shingles

A

suppress inflammation, pain and infection, antivirals in 72 hrs, valtrex 3-5 times bioavailability, wet compress 20 min several x/day; topical steroids, topical acyclovir, NSAIDs/lidocaine patch, TCA/gabapentin, opioids

49
Q

Dermatophyte infection

A

ability to infect and survive on dead keratin, classified by body region

50
Q

Diagnosis of fungal infection

A

KOH wet mount prep, most important test, direct visualization of hyphae in keratinized material, should obtain sample w/ 15# blades, fungal culture esp for hair and nail, woods light exam, light rays w/ wave-length >365 are produced when UV projected through woods filter

51
Q

Tinea pedis types

A

most common are by drmatophyte, toe web infection, chronic, scaly infection of plantar surface, acute vesicular tinea pedis, two feet one hand syndrome

52
Q

Toe web infection

A

tight fitting shoes compress toes- warm moist environment

53
Q

chronic scaly infection of plantar surface

A

plantar hyperkeratosis particularly chronic and resistant to treatment

54
Q

acute vesicular tinea pedis

A

acute form of infection often originates from more chronic web infection

55
Q

Two feet-one hand syndrome

A

nails may be involved, common in males, t rubrum is causative organism

56
Q

Treatment of tinea pedis

A

topical- lamisil cream, econazole, ketoconazole, oral antifungals, griseofulvin, fluconazole, itraconazole

57
Q

Pitted keratolysis

A

disease mimicking tinea pedia, an eruption ofwt bearing surface, hyperhirosis most common sx, malodor and sliminess, bacterial in origin, circular/ longitudinal, punched out depressions, bacteria secrete keratinase

58
Q

Treatment of pitted keratolysis

A

promote dryness, change socks frequently, 20% drysol, 10% formaldehyde, alcohol based benzoyl peroxide, topical abx may help

59
Q

Tinea cruris

A

Jock itch, common in men, unilateral and in crural fold, half moon shaped plaque forms as a well defined scaling border and advances into thigh, occasionally but/ gluteal cleft, usually not scrotum

60
Q

Treatment of tinea cruris

A

topical steroids often modify clinical presentation, topical antifungal, oral antifungal if not response

61
Q

Tinea of scalp

A

most frequent 3-7 yo, originates from contact w pet or infected person, hair shaaft infection preceded by infection of scalp, because of cuticle fungus has to circumvent and go deeper, hyphae growth=hair growth

62
Q

Clinical features of tinea of scalp

A

alopecia/ lymphadenopathy, kerion- boggy, indurated, tumor like mass that exudes pus, severe inflammatory rxn, scarring may occur, also present as black dot pattern, seborrheic dermatitis type, pustular type

63
Q

Treatment of tinea of scalp

A

diagnose w/ KOH wet mounts, culture or woodslamp, griseofulvin is drug of choice, terbinafine, itraconazole

64
Q

Candidiasis

A

lives w/ normal flora of mouth, infects only outer layer of epithelium of mucous membranes and skin, primary lesion is a pustule, clinically appears as red, denuded, glistening surface w/ long, scaling border, white curdy material

65
Q

Oral candidiasis

A

Thrush, manifestation of HIV, self limiting in healthy newborns, adults- depressed CMI, leukemia, broad spectrum abx, steroids and diabetes, perleche- involvement of corner of mouth, vit B12 def

66
Q

Treatment of oral candidiasis

A

fluconazole first line, itraconazole, ketoconazole, nystatin oral suspension

67
Q

Monilial vulvovaginitis

A

> 50% of women >25 develop, 30% tx w/ abx, vaginal itching, white discharge, red, swollen, painful genitals, satellite lesions

68
Q

Treatment of monilial vulvovaginitis

A

Topical antifungals, miconazole, clotrimazole, terconazole, nystatin, oral antifungals fluconazole, itraconazole and ketoconazole, do not give to pregnany pts

69
Q

Candidia of large skin folds

A

under breasts, groin, rectal area, contains heat, hot humid weather, tight underclothing, poor hygiene, first type-pustules, but macerate and form red papules w/ scales; second- red, moist, plaque extends beyond folds, wave shaped fringes

70
Q

Treatment of candidia of large skin folds

A

Educate about yeast, dry area, wet compresses to promote dryness, antifungal creams, absorbent powers- difficult to clean

71
Q

Diaper candidiasis

A

artificial intertriginous area is created under a wet diaper, treat by drying, change frequently, antifungal creams 2x daily, baby powders, mupirocin 2% cream if bacterial infection noted, erythema treat w/ 1% hydrocortisone

72
Q

Tinea versicolar

A

pityrosposum orbiculare and p ovale, areas w inc sebaceous activity, in stratum corneum and hair follicles where thrives on FFA and TGA, cushings, preg, malnutrition, immunsuppression, common during higher sebaceous activity

73
Q

Clinical features of tinea versicolar

A

mostly cosmetic, multiple small macules (varying colors), melanocyte damage basis of hypopigmentation, more obvious in nontanned regions, affects trunk, upper arms, neck, face in children, no sx, darker in blacks

74
Q

Diagnosis of tinea versicolar

A

KOH prep, hyphae and spores, wood light, irregular pale yellow to white fluorescence

75
Q

Treatment of tinea versicolar

A

ketoconazole 2% shampoo daily x3d, selenium sulfide 2.5% x 7 d, lamisil spray, itraconazole 200 mg x 7 d, difucan 300 mgx1 dose and repeat in 2 w, ketoconazole 400 mgx 1 dose, takes 6-8 weeks for pigment to return