Term
Normal flora of the skin? |
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Definition
Gram positive basteria:
Staphylococci (S. epidermis, S.aurus)
Streptococci (grp A,B,C,& G), S. pyogenes
corynobacterium, other diphteroids
propionobacterium (acne)
Fungi:
Malassezia sp
Candida sp
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Term
What is a common pathogen in SSTI? |
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Definition
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Term
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Definition
Acute inflamation of the skin and subcutaneous fat.
typically a diffuse, spreading skin infection, most commonly affects extremeties (70%) |
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Term
Cellulitis is usually confused with what? |
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Definition
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Term
What are the causative organism of Cellulitis? |
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Definition
Gram +:
grp A Streptococci (S. Pyogenes (most common)
S. Aurus (MSSA)
MRSA (CA & HA) (usually associated w/ purulent cellulitis)
Gram -:
E.Coli
P. aeruginosa
Klebsiella pneumoniae
Exposure to lake or ocean water (pt hx):
Aeromonas hydrophilia & vibrio vulnificus |
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Term
How does a CA MRSA looks like? |
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Definition
Spider bite
characterized by necrotic centers |
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Term
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Definition
Inflammation of hair follicules, superficial infection involved only in the dermis
itchy red papules appear ~ 48 hrs after exposure
Evolves into pustules that generally heals without tx in several days
Systemic symptoms uncomon |
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Term
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Definition
Abscess or boil
walled of pocket of pus from a hair follicle
involves deeper layers of skin
occur (in area of friction perspiration) as single or multiple nodules
Gradually become red, firm and painful
Drain by themselves |
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Term
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Definition
Multiple furincles unite into one big mass
Extended into subcutaneous tissues
Masses draines through many sinus tracts
Common in back of neck in diabetics
systemic symptoms often present (chills, fever, malaise)
spread to other tissues/bacteremia (causes serious concern) |
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Term
What is the most common cause of folliculitis, furuncles and carbuncles? |
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Definition
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Term
How we treat folliculitis/small furuncles? |
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Definition
use moist heat to promote drainage |
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Term
How we treat large furuncles/all cabuncles/abscesses? |
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Definition
Incision & drainage
PO abx not necessary except:
Extensive surrounding cellulitis
Fever |
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Term
What are local findins for Cellulitis? |
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Definition
Macular erythema
Generalized swelling
Warm to the touch
Tenderness
Tender, regional lymphadenopathy
Lymphagitis (sometimes)
Abscess (sometimes)
Yellow indicates severe cellulitis |
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Term
What are systemic findings for cellulitis? |
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Definition
Fever, chills
Hypothermia
Increase WBC
Tachycardia
Hypotension
Confusion in elderly
Septic shock |
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Term
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Definition
No evidence of significant infction, no significant comorbidities, uncomplicated |
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Term
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Definition
Evidence of infection, systemic signs limited to fever/increase WBC or infection somewhat localized |
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Term
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Definition
Diffuse infection, several systemic symptoms, significant comorbidities |
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Term
What laboratory values needed for systemic symtpoms? |
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Definition
CBC w/ differential
C-reactive protein
Creatinine
Bicarbonate
Creatinine phosphokinase
Blood cultures (+<5%)
culture/punch biopsies (5-40% +)
Drug susceptibility |
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Term
What are complications associated with cellulitis? |
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Definition
Osteomyelitis (w/ or w/o amputation)
Bacteremia, sepsis |
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Term
Treatment of mild cellulitis? |
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Definition
Clean site (soap/H2O), irrigate, remove foreign bodies
No abx needed unless immunocompromises or DM patients use Topical abx:
- Mupirocin (bactroban)
- Neomycin/polymixin/bacitracin (Neosporin)
(weaker activity against S. aureus) (toxic if applied to open wound)
- Clindamycin, erythromycin or benzoyl peroxide |
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Term
Treatment moderate cellulitis? |
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Definition
Cover S.pyogenes, S. aureus (MSSA):
- Dicloxacillin
- Cephalexin
if IV needed:
- Nafcillin
- Cefazolin
If PCN allergic:
- Clindamycin, vancomycin, TMP-SMZ
Treat for 5-10 days |
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Term
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Definition
TMP-SMX
Doxycycline
Minocycline
Linezolid
Clindamycin
Duration: 7-14 days |
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Term
What test is used to show resistance to clindamycin? |
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Definition
D-test uses for MRSA clindamycin resistanceif Positive= MRSA resistant to Clinda
Negative= MRSA susceptible to Clinda |
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Term
Treatment for severe cellulitis? |
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Definition
IV required:
Coverage for S. pyogenes, MSSA:
- Nafcillin
- Cefzolin
Is PCN allergic: Clindamycin, Vancomycin
Duration: 7-10 days |
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Term
Therapy for severe MRSA SSTI? |
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Definition
Vancomycin (dosed based on renal fct)
Linezolid
Daptomycin
Telavancin
Clindamycin
Duration: 7-14 days |
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Term
What are 2nd/3rd line alternatives w/ MRSA? |
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Definition
- Tigecycline (Tygacil)
- Quinupristin-dalfopristin (synercid)
- Rifampin-not used monotherapy |
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Term
For moderate/ severe treatment when to convert to PO? |
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Definition
when afebrile for > 4-5 days, then 10-14 d therapy w/ PO |
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Term
Waht does lack of response to therapy indicates? |
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Definition
- Misdiagnosis
-Abx resistance
-Non-adherence
-Subtherapeutic doses |
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Term
Special populations treatment? |
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Definition
IV drug abuser:
Add S. epidermis, P,aeruginosa to causative organisms (if severe)
Abx resistance (MRSA)
Immunocomprimised:
more aggressive tx, may treat longer than 10 d
must consider fungi, viral, atypicals |
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Term
What therapy is not recommended when MRSA decolonization? |
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Definition
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Term
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Definition
- Nasal decolonization with mupirocin BID for 5–10 days
–Nasal decolonization with mupirocin BID for 5– 10 days & a skin antiseptic solution (eg, chlorhexidine) for 5–14 days or dilute bleach baths
–For dilute bleach baths, 1 tsp per gallon of water [or ¼ cup per ¼ tub or 13 gallons of water] given for 15 min twice weekly for 3 months can be considered |
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Term
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Definition
Grp A strep (S. pyogenes) |
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Term
What distinguish erysipelas from cellulitis? |
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Definition
Characteristic lesion is raised and clearly dermacated |
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Term
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Definition
PCN drug of choice
Mild-moderate:
-Procaine PCN G
-PCN VK
PCN allergy:
-Clinda
-Erythromycin
Duration: 7-10 days
Severe: need hospitalization use aqueous PCN G |
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Term
What causes impetigo?
Superficial infection |
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Definition
S. pyogenes/ S.aureus
Itchy, purulent discharge; dries to golden yellow crusts |
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Term
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Definition
Mild: topical mupirocin
numerous lesion/lack of response to topical: PO
-Dicloxacillin
-1st gen cephalosporin
- PCN VK (S.pyogenes)
PCN allergic:
-Clindamycin
Duration: 7-10 d (7 d clinical response) |
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Term
Necrotizing fasciitis presents like cellulitis except? |
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Definition
Severe, constant pain, bullae, skin necrosis, gas in soft tissues, edema extending beyond margin, systemic symptoms (fever, increase WBC, delirium, renal failure), rapid spread despite abx |
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Term
What cause type 1 poly-microbial necrotizing fasciitis? |
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Definition
Bacteria:5 organisms at same time common
Gram -, anaerobes (clostridia bacteroides), enterococcus
Assosiated w/:
-abdominal surgery
-Decubitis ulcers
-IV drug use
-Bartholin abscess |
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Term
What causes type 2 mono-microbial necrotizing fasciitis?
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Definition
Bacteria: S.pyogenes, S. aureus (& MRSA), V. vulnificus, A.hydrophilia, anaerobic strep sp, clostridia sp (rare)
Associated w/:
DM, ASCVD, PVD |
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Term
Treamtent of necrotizing fasciitis? |
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Definition
Surgery: aggressive surgical exploration/dbridement required
Abx: type1: coverage for anaerobes, S.aureus/S.pyogenes, G-
Type 2: coverage for S.pyogenes/S.aureus, clostridia if gas present
Hemodynamic support: shock tx, etc.. |
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Term
When Hyperbaric oxygen is used? |
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Definition
Mostly w/ clostridial myonecrosis |
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Term
Bite wounds: cat causative organisms? |
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Definition
Pasteurella multocida (G-) (75%)
S. Aureus/S.yogenes (G+)(40%)
Anaerobes (A) (65%) |
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Term
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Definition
Pasteurella multocida (G-) (50%)
S.aureus/S.pyogenes (G+) (40%)
Anaerobes (A) (50%) |
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Term
Human bite causative organisms? |
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Definition
Viridans Strep (G+) (100%)
Bacteroides sp (G- A)(82%)
S.epidermidis (G+) (53%)
Corynebacterium (G+)(41%)
S.aureus (G+)(29%)
Peptostreptococcus (G+A)(26%)
Eikenella (G-A)(15%) |
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Term
Treat bite with abx when? |
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Definition
Wound involves hand/near joint
Deep puncture (cat)/difficult to irrigate
Immuno compromised
tetanus prophylaxis may be needed
Consider rabies if in area/unprovoked attack by wild animal |
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Term
Drug of choice (cat/dog bite wounds)? |
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Definition
Amoxicillin/clavulanic acid 875/125 mg BID * 5-10d
PCN allergy:
Doxycycline (not if <8yo)
SMX-TMP
+ Clindamycin
for 5- 10 d |
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Term
Drug of choice Human bite? |
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Definition
Augmentin 875/125 mg BID * 5-10 d
if PCN allergic:
Clindamycin + SMX/TMP * 5-10 d
If severe infection at presentation, then IV may be required |
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Term
What are complications of bite wounds? |
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Definition
Septic arthritis, osteomyelitis, subcutaneous abscess, tendonitis, bacteremia (rare), tetanus, rabies (rare, but life threatening) |
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Term
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Definition
Clostridium tetani (G+ anearobe)
vaccine immunizes against exotoxin C. tetani |
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Term
Which wounds are most at risk for tetanus? |
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Definition
> 6 hrs old, > 1cm deep, contain devitalized tissue, contaminated w/ dirt, saliva, etc... injury d/t crush, burn, frosbite, puncture |
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