Snapshot A 5-year-old boy presents to the emergency room with 5 days of fevers, ranging from 102-104°F (38.9-40°C). His mother reports that he also has a bad rash that developed on day 3. On physical exam, he has bilateral conjunctivitis, an extensive morbilliform rash on his trunk with desquamation, a bright red tongue, and swollen hands and feet. Labs are remarkable for elevated C-reactive protein, white blood cell count, and erythrocyte sedimentation rate. He is immediately given intravenous immunoglobulin and aspirin and sent for an echocardiogram. Introduction Clinical definition acute febrile medium-vessel vasculitis, also known as mucocutaneous lymph node syndrome, characterized by CRASH and burn Conjunctival injection Rash Adenopathy Strawberry tongue Hand and foot rash fever (burn) Epidemiology Demographics children < 5 years of age more common in those of Asian descent Risk factors family history being of Asian or Pacific Islander descent ETIOLOGY Pathogenesis unknown but thought to involve infection, environmental factors, immunologic abnormalities, and genetics Presentation Symptoms 5 days or more of high fever arthritis may be reported Physical exam bilateral non-purulent conjunctival injection rash erythematous morbilliform rash with desquamation on the trunk that may spread may also be urticarial or erythema multiforme-like non-vesicular erythema and swelling of the hands and feet with desquamation oral mucositis red cracked lips strawberry tongue asymmetric cervical adenopathy firm, unilateral, and nontender Imaging Echocardiography indications for all patients with Kawasaki disease to assess for cardiac abnormalities obtained at the time of diagnosis and again at 2 and 6-8 weeks after diagnosis Studies Labs ↑ inflammatory markers ↑ C-reactive protein ↑ erythrocyte sedimentation rate ↑ platelet count (often at weeks 2-3) ↑ white blood cells ↑ liver transaminases Differential Takayasu arteritis distinguishing factors weak upper extremity pulses no hand/foot rash or strawberry tongue Scarlet fever distinguishing factors sandpaper-like rash in the setting of group A streptococcal pharyngitis Staphylococcal scalded skin syndrome distinguishing factors + Nikolsky sign DIAGNOSIS Making the diagnosis diagnostic criteria fever for 5 or more days (burn) 4/5 of CRASH Conjunctival injection Rash Adenopathy Strawberry tongue Hand and foot rash Treatment Management approach treatment includes both intravenous immunoglobulin and aspirin Medical intravenous immunoglobulin (IVIG) indications for all patients prevention of coronary artery involvement high-dose aspirin indications for all patients high dose initially with subsequent switch to low-dose aspirin continued if coronary artery abnormalities are present discontinued only if imaging confirms no coronary artery abnormalities weeks after onset of Kawasaki disease anticoagulation indications for patients at risk of thrombosis with thrombocytosis drugs warfarin vaccinations indications prevention of viral infections while on aspirin therapy recall that viral infection with aspirin may cause Reye syndrome in children Complications Cardiac sequelae coronary artery aneurysm in 25% of patients may lead to death myocarditis myocardial infarction Prognosis Usually self-limited and resolves with treatment 25% of patients have cardiac sequelae may lead to fatal or nonfatal myocardial infarctions years after initial onset of disease may lead to fatal rupture of aneurysm