Abstract
RATIONALE: Kawasaki disease (KD) is a vasculitis syndrome of small to medium-sized arteries that has typical clinical characteristics such as fever, rash, cervical lymphadenopathy, conjunctivitis, and mucosal changes. Cardiac manifestations, including coronary artery aneurysms, myocarditis, myocardial infarction, and sudden cardiac death, are the most serious complications observed in KD. On rare occasions, it may accompanied with reduced organ perfusion due to systolic hypotension, a condition known as Kawasaki disease shock syndrome (KDSS). KDSS is a serious complication that can be presented to the emergency department as an initial feature when typical clinical symptoms of KD have not be detected. PATIENT CONCERNS: We report the case of a 12-year-old boy admitted with prolonged fever, bilateral non-purulent conjunctivitis, and signs of shock such as hypotension and tachycardia. Laboratory findings showed elevated inflammatory markers, hypoalbuminemia, and sterile pyuria. He was initially treated with intravenous cefotaxime and vancomycin considering the possible diagnosis of toxic shock syndrome, while the treatment was not effective. Subsequent chest computerized tomography and ultrasound identified pulmonary consolidation and polyserous effusion. Echocardiography revealed mild biatrial dilatation and mild valvular regurgitation with preserved left ventricular function. DIAGNOSIS: After a multidisciplinary consultation, a diagnosis of KDSS was made. INTERVENTIONS: To prevent coronary artery lesions and other severe complications, the patient immediately received immunoglobulin, corticoid, and acetylsalicylic acid. OUTCOMES: Soon afterwards, he showed significant improvement, with the temperature dropped to normal and hypotension corrected about 24 hours post-intravenous immunoglobulin therapy. Polyserous effusions also disappeared before discharge. Follow-up echocardiography revealed normal results. LESSONS: Clinicians should maintain a high index of suspicion for KD and consider pulmonary involvement and polyserous effusions as potential complications. For children with KD, any symptoms pointing to infection should be carefully considered. When there is no etiologic evidence, antibiotics should be used with caution. Our case also highlights the importance of considering KDSS as a differential diagnosis in children presenting with prolonged fever and shock. Early recognition, timely treatment, and close monitoring are key to preventing severe complications and ensuring favorable outcomes in patients with KDSS.