Aims & Objectives: KD is the leading cause of pediatric acquired cardiac disease in developed countries. KDSS occurs approximately in 5–7% of KD cases; however, its recognition is difficult even among experienced clinicians. We describe the first retrospective multinational multicenter study of KDSS in LA children. Methods Retrospective descriptive study of pts with a discharge diagnosis of classic or incomplete (atypical) KD who met KDSS criteria at 39 main referral hospitals from 16 LA countries. Study period: January-1st-2009 to December-31st-2013. Results Among 976 enrolled KD pts, 8(0.81%) developed a KDSS. Classic and incomplete (atypical) KD was diagnosed in 6(75%) and 2(25%) pts, respectively. 5(62.5%) were female pts. 5(62.5%) pts were <60 months of age. Median length of hospitalization was 14(8–35) days. Median length of fever at admission was 6(4–8) days. In 3(37.5%) pts, sepsis/shock but not KDSS was the initial admission diagnoses. Antibiotics were given in all 8 pts prior to both final KD and KDSS diagnoses. On admission, 5(62.5%) pts looked poorly perfused, 5(62.5%) had thrombocytopenia, and 6(75%) hypoalbuminemia. IVIG, aspirin and steroids were given in 8(100%), 7(87.5%), and 5(62.5%) pts respectively. A second dose of IVIG was required in 4(50%) pts. Baseline echocardiograms showed: coronary artery dilations and/or aneurysms, 2(25.0%) pts; pericardial effusion, 2(25.0%); valvular insufficiency, 2(25.0%). No deaths occurred. Conclusions Our incidence of KDSS is lower than reports from developed countries. However, difficulties in diagnosing KD and KDSS, misdiagnosis with sepsis/shock, and the retrospective nature probably reveal underestimates. KDSS cases were associated with prolonged hospitalizations, high rates of antibiotic use, and IVIG-resistance.