We thank Dr. Kotnik and colleagues for their comments on the American College of Rheumatology's clinical guidance for pediatric patients with MIS-C. The use of anticoagulation therapy in this population remains an intensely debated topic with little clinical evidence to guide treatment decisions. For this reason, the Task Force was only able to achieve consensus in recommending anticoagulation therapy in patients with larger coronary artery aneurysms (z-score >10) and significant cardiac dysfunction (ejection fraction <35%) based on the well-established risk of thrombosis in patients with these clinical features (1,2).Panelists reported significant variability in strategies for anticoagulation therapy in MIS-C, with some centers adopting approaches similar to those recommended by Kotnik et al and others avoiding anticoagulation therapy in most cases. Indeed, results from a recent survey from the International Kawasaki Disease Registry highlighted wide interinstitutional variation in use of anticoagulation therapy for MIS-C (3).In part, this heterogeneity stems from the lack of evidence on the risk of thrombosis in MIS-C. Complement activation and features of thrombotic microangiopathy have been documented in MIS-C; however, children with mild symptoms from severe acute respiratory syndrome coronavirus 2 infection display these same abnormalities. It is unclear if this endothelial dysfunction translates into increased rates of macrothrombosis requiring prophylactic or therapeutic anticoagulation (4). While in one study 7% of adolescents with MIS-C were reported to have developed deep venous thrombosis or pulmonary embolism, other large cohorts have demonstrated rates closer to 0-2% (5-7). This rate of thrombotic events is similar to that observed in children without MIS-C who have central venous lines, and many children with MIS-C require intensive care measures and central venous access (8). d-dimer levels are frequently elevated in MIS-C patients, but it is unclear if this laboratory parameter is directly reflective of hypercoagulability risk. There is some evidence to suggest that d-dimer levels may be elevated in inflammatory conditions without thrombosis (9,10). Further, the lack of data on d-dimer levels in children with profound inflammation makes it difficult to confidently use this parameter to guide anticoagulation therapy. Currently, there are no studies on the efficacy and safety of anticoagulation therapy in MIS-C. Thus, given the limited evidence and significant practice variability, the panel was not able to achieve consensus and provide further recommendations on anticoagulation therapy in MIS-C. The degree for anticoagulant thromboprophylaxis in children hospitalized for COVID-19-related illness [review].