SSTI Flashcards
PathophysiologyofSSTIs
Disruptionofnormalhostdefensesbyprocesses
suchas puncture,abrasion,diseases
Normalprotectingfactors of skins
Normalprotectingfactors –Drysurface –AcidicpH(~5.6) –Fattyacids –Renewalofepidermis –Lowtemperature
Predisposingfactors to ssti
Predisposingfactors –Highbacterialinnocula –Excessivemoisture –Reducedbloodsupply –Presenceofbacterialnutrients –Poorhygiene –Sharingofpersonalitems
Classification of SSTIs
Presence/absenceofdischarge
–Purulentversusnon‐purulent
Severityorextent
–Mildversusmoderateversussevere
–Uncomplicatedversuscomplicated
–Superficialversusdeep
Microbiology
–Singlepathogen(primary)versuspolymicrobial(secondary)
Anatomicalsite
–Hairfolliclesversusepidermisversusdermis,etc.
Classification according to anatomical sites
- Epidermis
impetigo
Classification according to anatomical sites
- dermis
Erysipelas
Classification according to anatomical sites
- Hair follicules
Folliculitis
Furuncles
Carbuncles
Classification according to anatomical sites
- Subcutaneous fat
Cellulitis
Classification according to anatomical sites
- Fascia
Necrotizing fasciitis
Classification according to anatomical sites
- Muscle
Myositis
Skinandsofttissueinfections shouldgenerally be treatedwithantibiotics
—- some can be treated by draining
Antibiotics(systemicandtopical)areavailableby prescriptiononly
–Exception:topicalclindamycin≤1%(acneonly)
Pharmacistsplayanimportantrole
– Referpatientstoseekmedicalcareifindicated
– Counselonnon‐pharmacologic approaches
– Recommendappropriateantibioticregimens
– Monitor forsafetyandefficacyoftherapy
Skinandsofttissueinfections shouldgenerally be treatedwithantibiotics
—- some can be treated by draining
Antibiotics(systemicandtopical)areavailableby prescriptiononly
–Exception:topicalclindamycin≤1%(acneonly)
Pharmacistsplayanimportantrole
– Referpatientstoseekmedicalcareifindicated
– Counselonnon‐pharmacologic approaches
– Recommendappropriateantibioticregimens
– Monitor forsafetyandefficacyoftherapy
Exclusionsforself‐treatmentofwounds
–Woundscontainingforeignobjects
–Chronicnon‐healingwounds
–Deepwounds
–Involvementofface,mucousmembrane,orgenitalia
–Woundsduetoanimalorhumanbites
–Noimprovementorworseningafter5days
–Signsofinfection
(PayattentiontoclinicalpresentationofSSTIs)
what is Impetigo
UncomplicatedformofSSTIaffectingtheepidermisorup tothedermal‐epidermaljunction
Commoninchildren
Highlycontagious
Ecthymaisformofimpetigo –Ulcerative–> scarring Usuallymanagedoutpatient
1) non-bullous
2) bullous (due to bacterial toxin production).
May rupture –> erythematous erosion
3) Ecthyma - more severe form. tend to form scar even after infection is clear.
Impetigo causative organism and culture
- S. aureus
- B-hemolytic streptococci (eg streptococcus pyogenes)
- Bullous form caused by toxin-producing strain of s. aureus
Cultures(optional)
– Maycultureifpusorexudate
– Reasonabletreatwithoutculture •EmpiricallycoverS.aureusANDβ‐hemolyticStreptococci
Hospital‐acquired(HA‐MRSA)
Community‐acquired(CA‐MRSA)
– Geneticallydifferentbackground
•Panton‐Valentineleucocidin(PVL)
•SCCmecIV
– Usuallysusceptibletooralnon‐beta‐lactams(e.g.clindamycin)
MRSA Risk factor
Hemodialysis Outpatientchemotherapy Long‐termcarefacilitiesresidents Athletes Militaryrecruits Menwhohavesexwithmen(MSM) HistoryofMRSAinfectionorcolonization