Bacterial Disorders of skin Flashcards
Cellulitis Definition
acute inflammation of dermis and subcutaneous tissue
Cellulitis Etiology
β-hemolytic streptococci (GABHS - pyogenes) (2/3)
Staphylococcus aureus (1/3)
Pseudomonas sp.
Haemophilus influenza
Cellulitis Predisposing Conditions
DM (diabetes mellitus) IV drug use cirrhosis renal failure tinea pedis immunosuppression surgical wounds chronic edema bite
Cellulitis Clinical features
unilateral
erythematous, warm, tender patch/plaque with irregular, ill-defined margins
fever, malaise, anorexia, chills, lymphadenopathy, systemic toxicity, lower extremity common
Cellulitis Diagnosis
clinical presentation
cultures
occasional biopsy
Cellulitis Differential diagnosis
stasis/contact dermatitis
superficial thrombophlebitis
deep venous clot
Cellulitis Treatment
PO antibiotics
elevation
supportive measures
occasionally IV antibiotics (+/- I&D)
Cellulitis Complications
sepsis gangrene lymphangitis recurrence chronic edema endocarditis
Cellulitis Prevention
support stocking
proper skin hygiene
early tinea pedis treatment
Erysipelas Clinical features
"acute illness" phase Unilateral erythematous raised indurated tender warm peau d' orange appearance sharp, elevated margins with predisposition for face, scalp, legs, abdomen lymphangitis common
Erysipelas Complications
sepsis; desquamation
chronic edema
lymphatic damage
Erysipelas Definition
acute superficial infection of the dermis (superficial subset of cellulitis)
Erysipelas Diagnosis
clinical appearance
cultures
neutrophilic leukocytosis
Erysipelas Differential diagnosis
contact dermatitis
thrombophlebitis
drug reaction
erythema migrans
Erysipelas Etiology
group A B-hemolytic streptococcus (pyogenes)
Erysipelas Predisposing conditions
malnutrition EtOH IV drug use stasis dermatitis lymphedema DM
Erysipelas Treatment
aggressive antibiotics
supportive/symptomatic
treat other skin conditions (+/- I&D)
Impetigo Clinical features
initial vesicle/pustule - ruptures and dries forming –honey-colored” crust with characteristic stuck on appearance
clustered or polycystic
occur anywhere
various stages seen
Impetigo Complications
post-strep glomerulonephritis
secondary infection
guttate psoriasis (rheumatic fever?)
Impetigo Definition
an acute, very contagious, superficial bacterial skin infection
Impetigo Diagnosis
appearance
cultures
Impetigo Differential diagnosis
varicella
herpes simplex
tinea corporis
Impetigo Etiology
Staphylococcus aureus»_space; B-hemolytic streptococcus
Impetigo Predisposing conditions
preexisting skin disease/minor breaks insect bites head lice trauma/burns poor hygiene staphylococcal colonization incisional sites warm/moist climates
Impetigo Prevention
adequate hygiene
Impetigo Treatment
local - topical cream/ointment; vinegar wet dressings
widespread - PO antibiotics
recurrent - swab/treat for colonization
Toxic Shock Syndrome CDC definition
fever diffuse rash mucus membrane hyperemia hypotension at least 3 organ systems involved (see Habif; Box 10.2; p. 310)
Toxic Shock Syndrome Clinical features
RAPID ONSET acute fever > 102 F hypotension myalgias rash + mucous membranes organ failure desquamation
Toxic Shock Syndrome Complications
death
Toxic Shock Syndrome Definition
acute toxin-mediated illness (menstrual & non-menstrual)
MEDICAL EMERGENCY
Toxic Shock Syndrome Diagnosis
clinical findings blood culture gram stain biopsy CDC criteria
Toxic Shock Syndrome Differential diagnosis
Scarlet fever pelvic infection septic abortion rubeola rheumatic fever
Toxic Shock Syndrome Etiology
S. aureus (tampon use)
Strep pyogenes strains can also be toxin-producing
Toxic Shock Syndrome Predisposing conditions
tampon use wounds cellulitis other infection foreign body (FB)
Toxic Shock Syndrome Treatment
remove FB
early empiric IV antibiotics
supportive care
ICU
Cellulitis Distribution
Lower extremity most common location
