Bacterial Skin Flashcards
What are the localized infections?
Folliculitis Cellulitis Erysipelas Abscess Impetigo
What are potentially lethal infections?
Necrotizing fasciitis Clostridial myonecrosis (gas gangrene)
What is the treatment for impetigo?
may resolve on it own or progress to cellultitis or glomerulonephritis
What is the systemic abx for impetigo?
Dicloxacillin 250-500 mg po q4-6h x 5-10d
What is the topical meds for impetigo?
Mupirocin (Bactroban) – apply tid x 5-10d
What pt education do you need for give for impetigo?
hand washing, don’t share towels, bed linens, wash lesions 2-3x a day or warm soaks
What are the general features of cellutitis and erysipelas?
varying degrees of skin or soft-tissue erythema, warmth, edema, and pain
associated fever and leukocytosis
history of trauma, abrasion, or skin ulceration (not reported by every patient)
How is celluitis on PE?
ill-defined border that merge smoothly with adjacent skin; usually pinkish to redish
What is erysipelas on PE?
elevated and sharply demarcated border with a fiery-red appearance
How do you dx celluitis and erysipelas?
clinically
What is the management of cellutitis and erysipelas?
local care - immoblize, elevate to reduce swelling
2 weeks of abx
-penicillin and dicloxacillin for most pt
What is the admission criteria for cellulitis?
Animal bite on patient’s face or hand
Area of skin involvement >50% of limb or torso, or >10% of body surface
Coexisting morbidity
(diabetes, heart failure, renal failure, generalized edema)
Edge of cellulitis advancing at rate >5cm/2 in, per hour
History of saphenous venectomy, pelvic surgery, pelvic irradiation, or neoplastic pelvic lymph nodes
(with lower extremity cellulitis)
Immunosuppression
Intolerance of oral or IM antibiotic therapy
Lack of response after 72 hours of oral therapy
Noncompliance with medication and follow-up visits
Purpuric or petechial rash, numbness at skin surface, or impaired tendon or nerve function
shock or disseminated intravascular coagulation
Signs and symptoms suggestive of bacteremia
Total WBC
What do you give for erysipleas most common?
pencillin V 500 mg po q6h
What do you give most common for cellulitis?
dicloxacillin 500 mg po q6h
What is inflammation of hair follicle that occurs as a result of various infections, or it can seconday to follicular trauma or occlusion?
Infectious folliculitis
What does infectious folliculitis looks like?
follicular based pustules, multiple small papules and pustules on an erythematous base that are pierced by a ccentral hair
What do deeper infectious folliculitis look like?
erythematous, often fluctuant, nodules
What orangism cause infectious folliculitis?
staphylococcus aureus
What is the topical treatment of infectious follicultis?
topical bactroban, dicloxacillin or cephalosporin first choice
What is chronic pustular staph infection of the beard?
pseudofolliculitis barbae
Who is pseudofollicuilits barbae more common in?
african americans
What is the treatment for pseudofollicultitis barbae?
skin cleanse, bacitracin, bactroban, erythro, diclox
What do you do for formed abscess?
I and D, give abx to immunocompromised (in real world give to all)
Streptococcal/Staph skin infection confined to epidermis
impetigo
infection of the skin and subcutaneous tissue. Flat lesions and edges are indistinct. Cause GAS
cellulitis
a type of cellulitis that is bright red, raised, with sharp borders.
erysipelas
What causes skin abscess?
s. aureus
What causes impetigo?
s. aureus, GAS
What are features of impetigo?
honey crusted lesions, kids get it, exposed areas, contagious
What are predisposing factors to impetigo?
poor hygiene, anemia, malnutrition, warm climates
What causes most cellulitis?
GAS and staph
How does cellulitis present?
boarders blend, redness, tender, deeper injury
Who can cellulitis be life threatening in?
immunocomp, DM, PV
What causes periorbital cellulitis in kids?
HIB
What does erysipelas require?
prompt tx
How does erysipelas spread?
superficial lymphatics
How does erysipelas appear?
confluent rash, sharply demarcated
abrupt with - fever chills pain
What is the tx for erysipelas?
pen or erythromycin, rest, elevation, warm compress
What does GAS cellulitis look like?
follow unnoticed injury, diffuse inflammation, spread on tissue planes
What does s. aureus cellulitis look like?
wound or pentrating trauma, local abscess becomes surrounded with cellulitis
What causes erysipelas?
GAS
What do you get when symptoms of toxicity or temp >102?
blood cultures
What do you give for penicillin resistant pt with cellulitis?
cephalexin 500 mg po qh6
clindamycin 450mg po qh6
cefazolin 1mg iv q8h
Where do you get hot tub folliculitis?
axillae, butt, trunk
How do you treat hot tub folliculitis?
self limiting
What does hot tube folliculitis look like?
follicular vesicular/pustular lesions
cluster of boils
carbuncle
What causes skin abscesses?
autoinoculation, immunosuppression, etoh, malnutrition
How do you tx skin abscess?
Dicloxacillin 250-500mg po q4-6h x 7-10d, erythromycin, cephalexin 500-1000 mg po qid 7-10d
Gangrenous cellulitis of the genitals
fournier’s gangrene
What causes ecthyma gangrenosum?
pseudomonas
What causes toxic shock syndrome?
s. aureus, GAS
a clopolymicrobial infection, commonly caused by a mixture of anaerobic and aerobic bacteria
stridium species, enterobacteriaceae (E. coli, Enterobacter, Klebsiella, and Proteus species), and “flesh-eating” streptococci
necrotizing fasciitis
Where does necrotizing fasciitis start?
site on nonpenetrating trauma (a bruise)
Who are more prone to necrotizing fasciitis?
DM, PV, ETOH, IV drug use, immunosuppression
What does the infected area look like in necrotizing fasciitis?
swollen, erythematous, painful, warm, tender
rapidly advancing boarders
discoloration
How do you treat necrotizing fasciitis?
surgical debridement emergent metronidazole+clindamycin+ceftriaxone vancomycin+ piperacillin tazobactam/imipenem/meropenem/clinda Ampicilin sulbactam + clinda + cipro antibiotics for a minimum of 3 wks
What causes myonecrosis (gas gangrene)?
clostridium perfringens
What does myonecrosis look like?
gas, local edema, pain, fever
What is the incubation period for myonecrosis?
hr to days
What is the discharge like for myonecrosis?
serosanguinous, dirty, foul smelling
How do you treat myonecrosis?
IV vanco + zosyn/meropenem/clinda
surgical debridement of infected muscles
A Necrotizing Soft Tissue Infection caused by Pseudomonas in immunocompromised patients
ecthyma gangrenosum
How do you treat ecthyma gangrenosum?
antipseudomonal penicillin (piperacillin) should be used in conjunction with an aminoglycoside (gentamicin) fluoroquinolones, third-generation cephalosporins, or aztreonam also effective
Mupirocin
Bactroban
