136 - FACTORS ASSOCIATED WITH IMPORTANT CORONARY ARTERY ANEURYSMS FOR KAWASAKI DISEASE VERSUS MULTISYSTEM INFLAMMATORY SYNDROME IN CHILDREN ASSOCIATED WITH COVID-19: A STUDY OF THE INTERNATIONAL KD REGISTRY

Background: Coronary artery (CA) involvement is an important outcome for both KD and MIS-C patients. We sought to determine associations of CA aneurysms with clinical features for both conditions.

Methods: Across 40 sites, the International KD Registry enrolled 2146 contemporaneous patients with MIS-C and 1358 with KD from January 2020 through October 2023. Adequate echocardiography was not available for 259 MIS-C and 164 KD patients. CA aneurysm was defined as a maximum Z score in any branch >5 (at least medium-sized). Characteristics and treatment of patients with vs. without aneurysms were compared separately for diagnosis groups.

Results: For 1887 included MIS-C patients, 23 (1.2%) had CA aneurysm(s). Z >10 was noted for 6 and >20 for 2 patients, with 14 having only one branch involved with an aneurysm, 5 with 2, 2 with 3 and 2 with 4 branches. For 1194 included KD patients, 86 (7.2%) had CA aneurysm(s). Z >10 was noted for 27 patients, >20 for 12 and >30 for 4 patients, with 32 having only one branch involved with an aneurysm, 17 with 2, 15 with 3 and 22 with 4 branches. MIS-C patients with vs. without aneurysms did not differ by age, sex, and body mass index Z score (zBMI), but were more likely to be Hispanic (71% vs. 30%; p=0.002) and less likely to be White (0% vs. 32%; p=0.008). For KD, aneurysm patients were younger (median 1.92 vs. 2.92 years; p< 0.001), with no differences for sex, zBMI or ethnicity. Unlike MIS-C patients, KD aneurysm patients had fewer KD clinical criteria. There were no differences regarding presentation with shock, but more KD aneurysm patients had ICU admission (19% vs. 6%; p< 0.001). Significantly higher peak WBC, neutrophils, lymphocytes and platelets, with lower trough hemoglobin were noted for aneurysm patients in both groups. KD aneurysm patients only had lower median trough albumin (28 vs. 37 g/L; p< 0.001); other labs were not different for both groups. Treatment for MIS-C aneurysm patients did not differ except for TNFalpha inhibitors (39% vs. 5%; p< 0.001). KD aneurysm patients were significantly more likely to receive intravenous and oral steroids, and IL-1 and TNFalpha inhibitors.

 


Conclusions: Important CA aneurysms are less prevalent and less severe in MIS-C vs. KD patients, and associated factors were not consistent between the two groups. Further follow-up of MIS-C patients is necessary to determine any differences in longer-term outcomes.