Download Skin and Soft-Tissue Infections - Hatzalah of Miami-Dade

Skin and Soft-Tissue Infections
Superficial lesions vs Deadly disease
Outpatient Management and
Indications for Hospitalization
Nayef El-Daher, MD, PhD
Richard Magnussen, MD
J Crit Illness, 1998; 13(3):151-160
3/98
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Skin and soft-tissue Infections
• Localized infections
– cellulitis
– erysipelas
• Potentially lethal infections
– necrotizing fascitis
– myonecrosis
– pyomyositis
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Cellulitis and Erysipelas
pathogenesis
• Cellulitis
– group A streptococci
typically follows an innocuous or
unrecognized injury; inflammation is
diffuse, spreading along tissue planes
– staphylococcus aureus
usually associated with wound or
penetrating trauma; localized abscess
become surrounded by cellulitis
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Cellulitis and Erysipelas
pathogenesis
• Erysipelas
– caused most often by group A
streptococci
– rarely cased by ß-hemolytic
streptococci of the B, C, or G serologic
group
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Cellulitis and Erysipelas
diagnosis
• General features
– 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)
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Cellulitis and Erysipelas
diagnosis
• physical exam
– cellulitis has an ill-defined border that
merge smoothly with adjacent skin;
usually pinkish to redish
– erysipelas has an elevated and sharply
demarcated border with a fiery-red
appearance
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Cellulitis and Erysipelas
diagnosis
• laboratory exam
– needle aspiration of the leading edge of
the cellulitis should be obtained (1)
– elevated antistrptolysin O titer supports
diagnosis of streptococcal infection
– blood cultures for patients with
symptoms of toxicity or temp > 1020F
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1. Arch Intern Med 1990; 150:1907-1912
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Cellulitis and Erysipelas
management
• Local care
– immobilization
– elevation to reduce swelling
• 2 weeks of antibiotic therapy
– penicillin and dicloxacillin for most pts
– many new, potent and expensive
antibiotics offer no advantage
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Outpatient Therapy
Infection
Cellulitis
mild-mod
severe
Erysipelas
mild-mod
severe
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Most patients
Pencillin allergic patients
Dicloxacillin
(500 mg po q6h)
Nafcillin 1-2g iv q4h
Vancomycin 1g iv q12h
Cephalexin 500mg po q6h
Clindamycin 450mg po q6h
Cefazolin 1g iv q8h
Penicillin V
(500 mg po q6h)
Cephalexin 500mg po q6h
Erythromycin 500mg po q6h
Clindamycin 450mg po q6h
Cefazolin 1g iv q8h
Clindamycin 900mg iv q8h
Pen G 1-2 million U q6h
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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 exceeding
5cm, or 2 in, per hour
• History of saphenous venectomy, pelvic surgery,
pelvic irradiation, or neoplastic pelvic lymph
nodes (with lower extremity cellulitis)
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Admission Criteria for Cellulitis
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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 < 1000 / uL
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Necrotizing Fasciitis
pathogenesis
• a polymicrobial infection, commonly
caused by a mixture of anaerobic
and aerobic bacteria
– clostridium species, enterobacteriaceae (
E. coli, Enterobacter, Klebsiella, and
Proteus species), and “flesh-eating”
streptococci
• usually starts at the site of
nonpenetrating trauma (a bruise)
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Necrotizing Fasciitis
diagnostic clues
• Underlying diabetes mellitus, peripheral
vascular disease, alcoholism, intravenous
drug use or immunosupression
• Most often involve the lower extremities
• Infected area is swollen, erythematous,
painful, warm, and very tender
• Rapidly advancing border (5 cm, or 2 in, per
hour) of discoloration (red to blue-gray)
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Necrotizing Fasciitis
diagnostic clues
• Bulllae formation and cutaneous gangren
• Frank pus in discolored area (revealed by
needle aspiration or surgical exploration)
• Numerous bacteria evident on the Gram stain
• Tendon or nerve impairment (superficial
nerve destruction and small vessel
thrombosis)
• Systemic toxicity and/or hypotension
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Necrotizing Fasciitis
management
• Immediate surgical debridement is critical and
life saving
• empiric antibiotics to cover anaerobes, gram
negative bacilli, streptococci, and Staph
aureus
– pen+metronidazole+clindamycin+ceftriaxone
– vancomycin+chloramphenicol
– monotherapy with imipenem
• antibiotics for a minimum of 3 wks
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Myonecrosis (Gas Gangrene)
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a pure Clostridium perfringens infection
gas in a gangrenous muscle group
incubation period of hours to days
local edema and pain accompanied by fever
and tachycardia
• discharge is serosanguinous, dirty, and foul
• pen G (3-4 million U q4h) or chloramphenicol
• surgical removal of infected muscle
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Pyomyositis (tropical myositis)
• 50% with co-morbidity (diabetes, alcoholic
liver disease, concurrent corticosteroid
therapy, immunosuppression)
• endemic in the tropics
• area is indurated with a “woody” consistency;
erythema and tenderness is minimal initially
• fever and marked muscle tenderness may
develop in 1-3 weeks
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Pyomyositis (tropical myositis)
• Rhabdomyolysis - along with myoglobinuria
and acute renal failure - may develop
• Staph aureus is the most common organism
• MRI or CT may show muscle enlargement
• surgical drainage is essential
• empiric antibiotics directed against Staph
– nafcillin 2 g iv q4h
– vancomycin 1 g iv q12h or cefazolin 1g iv q8h
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