Diagnosis

Kawasaki disease

Etiology

Cause [uvd][drk]

• Unknown

• Enviromental factors (infection): wind-borne or water-borne pathogen

• Autoimmune/genetic predisposition: HLA serotypes, family history

Pathophysiology [drk][uvd]

1. Stage 1: The acute febrile stage [drk]

   • Abrupt onset of fever and mucocutaneous clinical findings.

   • Vasculitis: The endothelial cells and the vascular media become edematous.

   • Immunological activation: Neutrophils, CD8+ lymphocytes, IgA–producing plasma cells, cytokines (TNF, VEGF), interleukins, and MMPs

   • Vascular damage (sometimes transmural necrosis --> leading to aneurysms

2. Stage 2: The subacute stage [drk]

   • Desquamation of the digits, thrombocytosis.

   • The inflammatory cells are replaced by fibroblasts and monocytes

   • Fibrous connective tissue begins to form within the vessel wall

   • The vessel wall eventually becomes narrowed or occluded owing to stenosis

     • Vasospasm, thrombosis, rupture of aneurysm --> cardiac complications (9%)

3. Stage 3: The convalescent phase [drk]

   • Complete resolution of clinical signs of the illness, usually within 3 months

   • Cardiac abnormalities may still be apparent and coronary artery aneurysms may rupture in adult life

Complications [uvd]

• Heart failure

• Myocarditis

• Valvulitis

• Pericarditis

• Myocardial infarction (MI)

• Rupture of the coronary arteries

• Ischemia-related dysrhythmias

• Death

Risk of oronary artery aneurysms [uvd]

• Fever >8 days (most important risk factor)

• Recurrence of fever after a period of being afebrile for 48 hours

• Male (3 times more likely to develop giant aneurysms)

• Cardiomegaly

• <1 year old of age

• Lower IgG levels

• Increased pro-BNP levels

• Increased TNF-alpha levels

• Thrombocytopenia at initial presentation

• Incomplete Kawasaki Disease Diagnosis 

Epidemiology

Incidence per 100.000 [iem][yg3][rnr]

Approach

• ECG

• Echocardiography

• MRI

• MR angiography

• Coronary angiography

• Chest x-ray

• Abdominal ultrasound

• Ultrasound scrotum

• Arthrocentesis

• Lumbar puncture

• Skin biopsy

Diagnostic criteria [yg3]

1. Fever of at least five days duration

2. Plus at least four of the following features:

   • Polymorphous rash 

   • Bilateral non-purulent conjunctivitis 

   • Changes in the peripheries 

   • Oropharyngeal changes 

   • Cervical lymphadenopathy

Treatment

1. Intravenous immunoglobulin: 2 g/kg given as a single infusion over 10–12 hours [yg3]

   • Failure to respond --> second dose

   • Failure to respond  --> intravenous methylprednisolone

2. Aspirin: 50–100 mg/kg/day is given acutely until the fever defervesces [yg3]

   • Aspirin 2–5 mg/kg/day until echocardiography at six weeks after diagnosis is normal

   • If abnormal echocardiography --> continue Aspirin

3. Anti-cytokine therapies: unproven but have occasionally been used [yg3]

Differential diagnoses

Adenovirus, Cellulitis, Leptospirosis, Lyme disease, Lymphadenopathy, Mastoiditis, Measles, Meningitis, Mercury toxicity, Mononucleosis, Myocardial infarction, Parvovirus B19, Peritonsillar abscess, Polyarteritis nodosa, Retropharyngeal abscess, Rheumatic fever, Rheumatoid arthritis, Rocky mountain spotted fever, Scarlet fever, Staphylococcal scalded skin syndrome, Systemic lupus erythematosus, Toxic epidermal necrolysis, Toxic shock syndrome, Typhus