Abstract Body (Do not enter title and authors here): Background: Kawasaki disease (KD) is a systemic vasculitis that is rare and underdiagnosed in adults given its atypical presentation, especially in non-Asian patients. Incomplete KD is characterized by less than 4 of the classic clinical findings of mucocutaneous inflammation and is more common in adults. Kawasaki shock syndrome (KSS) is a rare complication that has features of both cardiogenic and vasoplegic shock.

Case: A 48-year-old Black male was admitted for subjective fevers, abdominal pain, cervical adenopathy, and jaundice. Labs include WBC count 13320/cmm with 85% neutrophils, total bilirubin 13.1 mg/dL, direct bilirubin 9.3 mg/dL, AST 64 U/L, ALT 191 U/L, ALP 143 U/L, GGT 201 U/L, and urinalysis with pyuria. Microbiological workup and abdominal imaging were unremarkable. Subsequently, he developed chest pain with hypotension, diffuse ST elevations on ECG, and hsTropI of 638 ng/L. Cardiac catheterization revealed no obstructive CAD but elevated filling pressures with cardiac index of 1.8 L/min/m2, suggestive of myopericarditis with cardiogenic shock. IABP was inserted. TTE revealed EF of 20-25% with global hypokinesis, reduced RV systolic function, mild MR, and mild pericardial effusion. Significant labs include ESR 102 mm/hr, CRP 22 mg/L, ferritin 775 ng/mL, albumin 2.3 gm/dL, hemoglobin 9.3 gm/dL, and platelets 703000/cmm. High-dose aspirin and colchicine were given with significant improvement. IABP was removed 2 days post-placement. Cardiac MRI at 1-week post admission revealed reduced LV systolic function and diffuse pericardial enhancement. Aspirin, colchicine, and GDMT were prescribed at discharge. At 2-week follow-up, symptoms had resolved with normalization of labs. Clinical findings, lab abnormalities, and resolution with high-dose aspirin were suggestive of incomplete KD. The patient was subsequently lost to follow-up.

Discussion: Incomplete KD should be considered in an adult patient with myopericarditis and evidence of severe systemic inflammation when all classic findings are not present as current criteria are intended for children. Cervical adenopathy and hepatitis are more common in adults while coronary artery aneurysms are rarer. Early mechanical support in KSS may be beneficial.