Rosen & Barkin's 5-Minute Emergency Medicine Consult (674 page)

CODES

117.1 Sporotrichosis

BASICS

• Results from the actions of a soluble epidermolytic exotoxin produced by
  Staphylococcus aureus:
  
  • Produced at a distant site of infection or colonization
    
  • Disseminates hematogenously
    
  • Lyses desmosomes of granular cells in the superficial epidermis
    
  • Results in generalized intradermal exfoliation
    
• Typically affects infants and children <6 yr of age:
  
  • Adults have specific staph antibodies allowing them to localize, metabolize, and excrete the staph toxins.
    
  • Infants and children are unable to metabolize and excrete toxin efficiently.
    
  • Immunocompromised adults and those with severe renal dysfunction are also susceptible
    
• Presentation determined by age and extent of rash:
  
  • Classic staphylococcal scalded skin syndrome
    
  • Pemphigus neonatorum
    
  • Bullous impetigo
    
  • Generalized in the newborn: Ritter disease
    
• Typically, coagulase-positive phage group II
  Staphylococcus:
  
  • Phage groups I and III also implicated
    

• Colonization often without overt infection
  
• Concurrent infection or break of skin barrier:
  
  • Nasopharynx
    
  • Urinary tract
    
  • Minor skin abrasions
    
  • Circumcision site
    
  • Conjunctivitis
    
  • Umbilicus/omphalitis
    
  • Impetigo
    
  • Endocarditis and septicemia
    
• Often no focus identified
  

DIAGNOSIS

• Constitutional symptoms:
  
  • Malaise
    
  • Fever
    
  • Irritability
    
  • Child may appear well, ill, or overtly toxic
    
  • Abrupt onset
    
• Scarlatiniform erythematous rash (sandpaper like) resembling a “sunburn”—erythroderma
  
• Exquisitely tender skin
  
• Areas of prominence:
  
  • Around the flexor areas of the neck
    
  • Intertriginous areas, especially axilla and groin
    
  • Near the eyes and mouth
    
  • Increased erythema in skin creases
    
• Facial edema with radial crusting fissures around the eyes, nose, and mouth
  
• Flaccid bullae:
  
  • Within 1–3 days after onset of rash
    
  • Initially over flexures (axillae, groin, body orifices)
    
  • Bullae migrate through epidermis with light lateral pressure; epidermis separates with minor pressure (Nikolsky sign).
    
  • Rupture within hours
    
  • Epidermis separates with minor trauma.
    
  • Epidermis is shed in sheets.
    
  • Denuded areas are moist, sensitive, and painful.
    
  • Complete healing within 2 wk, no scarring
    
• Purulent conjunctivitis
  
• Mucous membranes not affected
  
• Complications rare:
  
  • Hypothermia
    
  • Fluid and electrolyte imbalance
    
  • Secondary infection
    
  • Pneumonia
    
  • Septicemia
    
  • Cellulitis
    
  • Osteomyelitis
    

• Clinical presentation is diagnostic.
  
• Determine location/source of toxin producing
  Staphylococcus.
  
• Assess systemic nature of infection.
  

• CBC and urinalysis:
  
  • Assess for sepsis if source not obvious.
    
• Electrolytes:
  
  • Indicated if signs of dehydration or extensive rash
    
• Blood cultures (rarely positive)
  

Indicated as need to determine location/source of infection

• Fluid aspirated from bullae:
  
  • Sterile in staphylococcal scalded skin syndrome
    
  • Consistent with hematogenous dissemination of the toxin
    
• Isolation of staphylococci from a site other than the blisters:
  
  • Commonly conjunctivae, nasopharynx, or blood
    
• Skin biopsy or frozen histologic section:
  
  • Determine level of epidermal/dermal separation (cleavage is in granular layer of dermis).
    
  • Indicated for children on medications, those >6 yr, and in cases of mixed presentation
    

• Infection:
  
  • Scarlet fever:
    
    • Involves the mucous membranes
      
    • Strawberry tongue
      
    • Painful desquamation does not occur
      
• Bullous impetigo:
  
  • Turbid or cloudy bullous fluid
    
• Bullous varicella:
  
  • Tzanck prep or viral base reveals giant cells.
    
  • 5 days after the onset of varicella
    
• Toxic shock syndrome:
  
  • Rapid development of clinical signs and symptoms
    
  • Mucous membrane and multiorgan involvement
    
• Toxic epidermal necrolysis or drug eruption:
  
  • Much more common in adults
    
  • Severely afflicted mucous membranes
    
  • Full-thickness epidermal necrosis
    
• Dermatologic:
  
  • Erythema multiforme
    
  • Epidermolysis hyperkeratosis
    
  • Epidermolysis bullosa
    
  • Pemphigus vulgaris
    
• Scald injury
  
• Secondary rash of an underlying disorder:
  
  • Lymphoma
    
  • Aspergillosis
    
  • Irradiation
    
  • Graft-versus-host reaction
    
  • Kawasaki disease
    

TREATMENT

• 9% NS fluid bolus if dehydration present
  
• Initial burn treatment
  

• Management is similar to an extensive 2nd-degree burn:
  
  • Involvement of large body surface area will require IV fluids.
    
• Provide adequate analgesia.
  
• Undress and place child on sterile linen.
  
• Limit handling of child.
  
• Apply moist sterile dressings.
  
• Avoid excess heat loss.
  

• Topical burn creams are of no proven benefit.
  
• Steroids are contraindicated.
  
• IV antibiotics effective against penicillinase-resistant
  S. aureus:
  
  • Cefazolin
    
  • Nafcillin
    
  • Vancomycin if methicillin-resistant
    S. aureus
    (MRSA) suspected
    
• Oral antibiotics for mild involvement:
  
  • Dicloxacillin
    
  • Erythromycin
    
  • Cephalexin
    

• Cefazolin: 50–100 mg/kg/24 h IV div. QID
  
• Cephalexin: 25–100 mg/kg/24 h PO div. QID
  
• Dicloxacillin: 12–25 mg/kg/24 h PO div. QID
  
• Erythromycin: 30–50 mg/kg/24 h PO div. QID
  
• Nafcillin: 1–2 g IV q6h (peds: Newborns, 50–100 mg/kg/24 h IV div. q6h; children, 100–200 mg/kg/24 h IV div. q6h)
  
• Vancomycin: 40 mg/kg/24h IV q 6 hrs
  

FOLLOW-UP

• Children <1 yr
  
• All toxic-appearing children
  
• Widespread skin involvement
  
• Dehydration and/or electrolyte derangement
  

• Older, well-appearing children with mild involvement
  
• Oral antibiotics for 7 days
  
• Follow-up within 48 hr