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Flashcards in 11 - Bacterial Infections Of Skin Deck (79):
1

List of bacterial infections of skin

Impetigo
Erysipelas
Cellulitis
Slistering distal dactylitis
Folliculitis
Sycosis barbae
Furnicle
Pseudomonas folliculitis and cellulitis
Trichomycosiasis axilaris
Erythasma
Pitted keratolysis

2

What accounts for the maj of skin and soft tissue infections?

Staphylococcus aureus and group A beta-hemolytic streptococci

3

S. Aureus causes?

Invades the skin and causes
- impetigo
- folliculitis
- cellulitis
- furuncles

4

Elaborations of S. Aureus causes?

Leasions of bullous impetigo and SSSS

5

What does group A beta hemolytic strep cause?

Impetigo
Erysipelas
Cellulitis
Lymphangitis

6

Beta hemolytic strep causes?

Non bullous impetigo
Aka impetigo contagiosum

7

Progression of beta hemolytic strep - non bullous impetigo?

Starts as stratum corneum pustule or vesicle -> ruptures to expose a red moist base

Progresses to adherent “honey crusted” weeping lesions

8

Pt population for beta hemolytic strep - non bullous impetigo?

Kids 2-5
Warm moist climate
Poor hygeine

9

Beta hemolytic strep - non bullous impetigo often comes with?

Staph

10

Non derm symptom of beta hemolytic strep - non bullous impetigo?

regional LAD

11

Tx for beta hemolytic strep - non bullous impetigo?

Cool or warm soaks (remove crust)

Control infection (bactroban)

Systemic abx prn
- doxy

Dressing to prevent spread

Isolate pt

12

Beta hemolytic strep - eryspelas is aka?

St. Anthony’s fire

13

What is erysipelas?

Superficial cellulitis of lymphatics
- erythema
- edema
- pain

Seen on: (2/2 vascular insufficiency)
- face
- ears
- legs

14

Presentation of Erysipelas?

Lymphatic cellulitis

Prodrome

Slightly raised plaque w sharp demarcation

Red, warm, tender

ILL w malase, fever, nodes

WBC elevated

15

Tx for erysipelas?

Systemic abx
- oral
- IV
Cephelexin, diclox etc

16

cellulitis?

infection that extends into sub Q

17

Etiology of cellulitis?

GABHS (MC)
Staph
H. Flu (kids <2)
Pseudomonas (DM)

18

Where does cellulitis present?

Usually areas compromised by stasis/lymphedema

19

cellulitis presentation?

- erythema, edema, TTP (diffuse)
- no sharply defined border
- red streaks w swollen nodes
- vesicles or bullae
- dusky red skin
- constitutional ssx
- H WBC

20

cellulitis tx?

Cool compress
Elevation

Outpatient
- dicloxacillin, cephalexin
Inpatient
- IV Nafcillin
- IV vancomycin

Pesudomonas (DM)
- aminoglycosides

H. Flu
- cephalosporins

21

blistering distal dactylitis is?

Superficial infx of anterior fat pad of fingertips

22

blistering distal dactylitis is MC seen in?

Kids 2-16

23

Progression of blistering distal dactylitis ?

Faint erythema, Vesicles to oval 1-3cm bullae and exfoliation

24

Tx for blistering distal dactylitis?

I/D
Oral (anti-strep) abx x 10 days

25

Carriers of strep like to keep it?

Nasal
Axilla
Groin
Perianal area

26

MC secondary invader?

Staph aureus

27

Constitutional symptoms w Staph?

Nope

28

Staph toxin?

Epidermolytic toxin as in SSS or bullous impetigo

29

Staph aureus - bullous impetigo

Caused by toxin release in epidermis -> cleaving
- staph only (usually)

30

Bullous lesions are?

Less exudative crusting
- 1 or more vesicles enlarged rapidly to form bullae
- turn from clear to cloudy

31

Describe bullous impetigo?

Bullous lesion where the center collapses and leaves a TUBE-LIKE RIM

HONEY CRUST at center
- removal leaves bright red, moist base, that oozes

She said “youre taking the inter-tube down the staph river”

32

Tx for bullous impetigo?

Strict hand washing
Warm/coal soaks (remove crusts)
Muciprocin ointment
Systemic abx PRN

33

What is SSSS?

Staph scalded skin syndrome
- more diffuse form of bullous impetigo

34

What is folliculitis?

Inflammation of hair follicle
Typically caused by infection, chemical irritation, or physical injury

Think makeup, motor oil, steroid therapy

35

MC form of infectious folliculitis?

Staph folliculitis
- comes from the nose

36

Folliculitis workup?

Culture
- scrape and put on cotton swab

37

Tx for folliculitis?

Removal of occlusion/irritants etc
Good skin hygiene
Benzyol peroxide
Systemic abx

38

Long term scalp folliculitis?

Treat for folliculitis decalvans

39

What is sycosis barbae?

Inflammation of entire follicle
- staph impetigo of beard
- spread by razor

40

Tx for syscosis barbae?

Same as staph impetigo
- bactroban
- oral abx prn

41

Severe sycosis barbae?

Eval for dermatophyte infx
- remove hair for culture

42

Furncle vs carbuncle?

Furuncle - boil/abscess - walled off collection of pus
- painful
- firm
- fluctuant mass

Carbuncle - multi furncles

Furry uncles get together and get in a car...

43

Where do furuncles and carbuncles present?

Friction prone or traumatized areas
- thighs
- buttocks
- groin
- axillar
- waist

44

Tx for furuncle/carbuncle?

Primary: I/D
- moist heat to localize/spontaneously rupture (can also ease I/D)

Systemic abx prn
- not usually necessary

45

MRSA?

Consider w recurrent furnculosis
- mupirocin
- chlorhexidine/bleach baths

46

Abx for MRSA?

Septra
Clindamycin

47

Ecthyma?

Jungle sores
- like impetigo but worse

48

Ecthyma lesion?

Localized
Thick
Crusted
Exudative
Tumor-like lesion

Ulcers w crust
Heals w scar

Common on legs

49

Ecthyma tx?

Warm/coal soaks (remove crust)
Good hygiene
Dry dressing
Mupirocin
Dicloxacillin
Cephalexin

50

This gram neg organism is not part of the normal flora?

Pseudomonas aeruginosa

Seen in sugar aids pts

51

Pseudomonas aeruginosa causes?

Green pigment
- pyoverdin - seen on wood light
- light green

Fruity, grape like odor

52

Pseudomonas folliculitis is aka?

Hot tub folliculitis

53

Presentation of pseudomonas folliculitis?

Hx of hot tub 8hrs-5 days ago
Often seen on bathing suit lines

Multiple pruritic, round, urticarial plaques w/ central papule or pustule

Malaise w low grade fever

54

So i got drunk and got in a hot tub, what now?

Showering will not help so, just pray i suppose

Fortunately its usually a self-limiting disease (7-10 days)

55

Tx for pseudomonas folliculitis?

Antihistamine
- hydrozyzine (atarax) PRN
Vinegar soaks (acetic acid)
Domeboro’s
Burrows

Ciprofloxacin if severe

56

Pt population for pseudomonas cellulitis?

Debilitated sugar aids pt

57

pseudomonas cellulitis is?

2/2 infasion of tinea of toe webs or groin
Bed sores
Stasis ulcers
Burns
Grafted areas
Under foreskin
Or following injury

58

pseudomonas cellulitis is encouraged by?

Occlusion and or suppression of normal flora w broad spectrum abx

Seen in swampy environment

59

pseudomonas cellulitis can also be found?

Around ear
- due to external otitis

60

pseudomonas cellulitis tx?

DM - blood sugar
- watch for sepsis

Acetic acid
Domeboro (aluminum acetate)

Systemic abx
- oral cipro
- IV aminoglycosides

Severe inf
- clindafloxacin IV

61

Pseudomonas toe web infection?

Between 4th and 5th toe

Caused by moisture

Thick white macerated skin

Green fluoresence (woods light)

62

Pseudomonas toe web infection commonly mixed w?

Candida

Or other bacteria

63

Pseudomonas toe web infection txt?

Keep clean and dry
- sandals

Acetic acid soaks

Drysol (aluminum chloride)

64

What is trichomycosis axillaris?

Corynebacterium infection of the hair of the axilla

65

Describe trichomycosis axillaris?

Whitish or colored hair
Associated w heavy sweating
Malodorous (very)

66

Tichomycosis axillaris txt?

Shave area
Topical erythromycin
Topical naftifine (naftin)
Control hyperhidrosis
- antiperspirants
- drysol

67

What is naftifine (naftin) normally used for?

It is for superficial fungal (tinea)
Also has antibacterial properties

68

MC site for erythrasma - C. Minutissimum?

4th interdigital space

69

Other sites for erythrasma - C. Minutissimum?

Bilateral inguinal
Axillae
Inframammary fold

70

Describe erythrasma - C. Minutissimum?

Macular
Brown-red
Scaly
Noninflammatory

Itches
Burnes

Looks like T. cruris

71

Hwo to differentiate T. Cruris from C. Minutissimum?

KOH
Woods lamp

72

What does C. Minutissimum look like under a woods lamp?

Coral red fluorescence
- due to porphyrins produced by organism

73

Tx for erythrasma?

Keep clean and dry

Systemic (pick one)
- erythromycin
- clarithromycin

Topical (pick one)
- erythromycin
- clindamycin
- miconazole
- clotrimazole

74

Your pt presents with multiple 1-3mm pits to wt bearing areas of the feet

Pitted keratolysis

75

What causes pitted keratolysis

caused by micrococcus sedentarius which produces an enzyme that digests keratin

76

Symptoms of pitted keratolysis

1-3 mm pits to wt bearing areas
Hyper hydrosis
Malodor
Sliminess of skin

77

Pitted keratolysis is associated with?

The tropics
Occlusive footwear

78

Pitted keratolysis tx?

Clean daily
Promote dryness
Change socks
Rotate footwear

Drysol (20% aluminum chloride)

Topical ( pick one)
- erythromycin
- Clindamycin
- mupirocin

Oral (alternate treatment)
- erythromycin

79

What do you get from a pampered cow?

Spoiled milk