Rosen & Barkin's 5-Minute Emergency Medicine Consult (408 page)

BASICS

• Acute inflammatory process involving multiple organs
  
• Leading cause of childhood-acquired heart disease in developed countries
  
• Vasculitis is most severe in medium-sized arteries
  
• Acute cardiac sequelae:
  
  • Coronary artery aneurysm:
    
    • Often lead to stenosis after healing
      
  • Giant aneurysm:
    
    • May rupture
      
  • Myocarditis
    
  • Pericarditis
    
• Stages:
  
  • Acute (lasts 1–2 wk):
    
    • Fever
      
    • Oral mucosal erythema
      
    • Conjunctival injection
      
    • Erythema and edema of hands and feet
      
    • Cervical adenopathy
      
    • Aseptic meningitis
      
    • Hepatic dysfunction
      
    • Diarrhea
      
    • Myocarditis
      
    • Pericardial effusion (20–40%)
      
    • No aneurysms by ECHO
      
  • Subacute (when fever, rash, and lymphadenopathy resolve until about 4 wk):
    
    • Anorexia
      
    • Irritability
      
    • Desquamation of hands and feet
      
    • Thrombocytosis
      
    • Coronary artery aneurysms (20% if untreated)
      
    • Risk for sudden death is highest
      
  • Convalescent phase (about 6–8 wk):
    
    • Clinical signs are absent
      
    • ESR normalizes
      
  • Epidemiology:
    
    • 80% of cases occur in children <4 yr old; peak at 1–2 yr; rare in infants <3 mo old
      
    • Adult cases have been reported
      
    • Asians are at highest risk
      
    • Males > females 1.5:1
      
• Genetics:
  
  • Possible genetic predisposition
    
• Risks for nonresponse to standard therapy (10–15%):
  
  • Elevated band count
    
  • Low albumin level
    
  • Abnormal initial ECHO
    
• Risks for development of coronary artery aneurysms:
  
  • Extremes of age
    
  • Male gender
    
  • Prolonged fever
    
  • Persistent fever after treatment
    
  • Delay in diagnosis
    
  • Increased WBC and/or band count
    
  • Low hematocrit
    
  • Significant increase in CRP and/or ESR
    

• Unknown—believed to be infectious based on manifestations of disease, epidemics, and increased numbers of cases in winter and early spring
  
• Current theory:
  
  • Activation of immune system in response to infection
    
  • Genetically susceptible host
    
  • May explain why certain ethnicities have higher incidence of disease
    
    • More prominent in Asian countries
      

DIAGNOSIS

• Classic diagnostic criteria:
  
  • Fever for 5 days + 4 of the 5 following criteria:
    
    • Bilateral conjunctival injection
      
    • Changes in oral mucosa
      
    • Polymorphous erythematous rash
      
    • Changes in hands or feet—edema, erythema, desquamation
      
    • Cervical lymphadenopathy >1.5 cm (least common)
      
• Atypical cases can be seen without meeting diagnostic criteria
  
  • Fever for >5 days + 2 or 3 clinical criteria with ESR >40 and CRP >3
    
  • If >3 of the below can diagnose incomplete Kawasaki disease
    
    • Albumin <3
      
    • Anemia for age
      
    • ALT elevation
      
    • WBC > 15,000
      
    • Urine >10 WBC per high power field
      
    • Platelets >450,000 after 7 days
      
• Thrombocytosis
  
  • Changes in hands or feet—edema, erythema, desquamation
    
  • Cervical lymphadenopathy >1.5 cm (least common)
    

• Temperature >38.5°C (often spiking) for at least 5 days:
  
  • Begins abruptly and may last >2 wk
    
• Cardiac:
  
  • Shortness of breath
    
  • Chest pain
    
• HEENT:
  
  • Eyes:
    
    • Conjunctivitis
      
    • Photophobia
      
  • Mouth:
    
    • Erythema
      
    • Dry and fissured lips
      
• Skin rash
  
• Musculoskeletal:
  
  • Arthralgia, arthritis
    
• Neurologic:
  
  • Extreme irritability
    
• GI:
  
  • Diarrhea
    
  • Vomiting
    
  • Abdominal pain
    

• Cardiac:
  
  • Evidence of congestive heart failure
    
  • Evidence of pericarditis
    
    • Rub
      
  • Evidence of valvular disease
    
    • Murmur
      
• HEENT:
  
  • Eyes:
    
    • Bilateral conjunctival injection without exudates
      
    • Bulbar conjunctiva is more frequently involved than palpebral conjunctiva
      
    • Usually within 2 days of onset of fever and lasting 1–2 wk
      
    • Photophobia, uveitis, iritis
      
  • Mouth:
    
    • Erythema, dry and fissured lips, strawberry tongue, pharyngeal erythema
      
  • Lymph:
    
    • Cervical lymphadenopathy (node diameter >1.5 cm)
      
• Neurologic:
  
  • Irritability
    
  • Meningismus
    
• Skin:
  
  • Rash, primarily on the trunk
    
  • May be maculopapular, scarlatiniform, or erythema multiforme–like; erythroderma
    
  • Changes in the hands or feet—erythema, edema (acute phase); unwilling to bear weight
    
  • Desquamation (subacute phase) of the tips of fingers and toes 2–3 wk after onset of illness
    
• Genitourinary:
  
  • Urethritis
    
  • Meatitis
    
• GI:
  
  • Hydrops of the gallbladder
    

Must think of the diagnosis in a febrile child with rash

• CBC:
  
  • WBC—normally elevated with shift to left in acute phase
    
  • Normocytic anemia
    
  • Leukopenia and thrombocytopenia are rare
    
    • Suspect viral infection
      
    • Thrombocytopenia is a risk factor for development of coronary artery disease
      
• Urinalysis:
  
  • Sterile pyuria
    
  • Proteinuria
    
• ESR elevated from 1st wk until 4–6 wk
  
• Increased C-reactive protein
  
• CSF pleocytosis
  
• Cultures: Negative blood, urine, CSF, throat
  
• Increased transaminases and bilirubin
  

• ECHO to evaluate for coronary artery aneurysm:
  
  • Acute phase (baseline)
    
  • 2–3 wk
    
  • 6–8 wk
    
• CXR
  

• ECG if concern about MI or pericarditis
  
• Slit-lamp exam—uveitis
  

• Viral infections:
  
  • Adenovirus
    
  • Enterovirus
    
  • Measles
    
  • Epstein–Barr virus
    
  • Rubella
    
  • Rubeola
    
  • Influenza
    
• Bacterial infection:
  
  • Scarlet fever (responds rapidly to penicillin)
    
  • Staphylococcal scalded-skin syndrome
    
  • Rickettsial disease, including Rocky Mountain Spotted Fever and leptospirosis
    
  • Cervical adenitis
    
• Immune-mediated:
  
  • Stevens–Johnson syndrome
    
  • Erythema multiforme
    
  • Serum sickness
    
  • Connective tissue disease (i.e., Lupus)
    
  • Other forms of vasculitis
    

TREATMENT

• ABCs
  
• Oxygen
  

ABCs with focus on cardiovascular system

• Initiate IV gammaglobulin (IVIG) and aspirin therapy:
  
  • Do not generally need to monitor salicylate levels because of decreased absorption and increased clearance
    
• Treatment within the 1st 10 days of illness reduces cardiac sequelae from range of 20–25% to range of 2–4%.
  
• Cardiology consultation
  
• Treatment of MIs as in adults
  

• IVIG: 2 g/kg IV over 10–12 hr; retreatment may be required for persistent (>48–72 hr) or recrudescent fever:
  
  • Requires close cardiac monitoring
    
  • Should be started within the 1st 10 days of illness
    
  • 3–4% failure rate after 2 doses
    
• Aspirin: 80–100 mg/kg/d PO q6h until about day 14 when fever has resolved; then 3–5 mg/kg/d PO daily for 6–8 wk. Do not exceed 4g/24 h (peds: Do not exceed 120 mg/kg/24 h):
  
  • Anti-inflammatory
    
  • Antiplatelet
    
  • Potentiates the action of IVIG
    
  • Reduces the occurrence of aneurysms when given with IVIG
    
  • Alternative dosing at 30 mg/kg/d during acute and subacute phases
    

If no response to 2nd dose of IVIG

• Corticosteroids:
  
  • Methylprednisolone 30 mg/kg over 3 hr
    
  • May improve outcome in conjunction with IVIG