Multisystem Inflammatory Syndrome in Children - Characteristics, Therapies, and Outcomes

Multisystem Inflammatory Syndrome in Children (MIS-C) is a condition characterized by severe organ system inflammation and shock, presenting approximately 4-6 weeks after infection with the virus SARS-CoV-2. This disease was first identified in April 2020 and appears to be one of the most severe forms of disease associated with COVID-19 in children. A single-center retrospective study was performed on a cohort of patients diagnosed with MIS-C at Children\u27s Hospital and Medical Center in Omaha. A variety of data--including patient demographics, hospital course, treatments, and long-term cardiac outcomes--were analyzed to better understand MIS-C as an emerging disease.https://digitalcommons.unmc.edu/surp2021/1006/thumbnail.jp

Intraventricular Septation in the Context of Dilated Cardiomyopathy Associated With TTN Mutation

A 6-month-old infant boy presented with symptomatic heart failure. Dilated cardiomyopathy was found in association with a mutation in TTN. Structural heart disease included novel septation of the left ventricle with a fenestrated membrane resulting from aberrant congenital mitral valve apparatus formation. (Level of Difficulty: Advanced.)

A contemporary comparison of the effect of shunt type in hypoplastic left heart syndrome on the hemodynamics and outcome at stage 2 reconstruction

ObjectiveWe compare the hemodynamics and perioperative course of shunt type in hypoplastic left heart syndrome at the time of stage 2 reconstruction and longer-term survival.MethodsWe retrospectively reviewed the echocardiograms, catheterizations, and hospital records of all patients who had a stage 1 reconstruction between January 2002 and May 2005 and performed a cross-sectional analysis of hospital survivors.ResultsOne hundred seventy-six patients with hypoplastic left heart syndrome and variants underwent a stage 1 reconstruction with either a right ventricle–pulmonary artery conduit (n = 62) or a modified Blalock–Taussig shunt (n = 114). The median duration of follow-up is 29.1 months (range, 0-57 months). By means of Kaplan–Meier analysis, there is no difference in survival at 3 years (right ventricle–pulmonary artery conduit: 73% [95% confidence limit, 59%–83%] vs modified Blalock–Taussig shunt: 69% [95% confidence limit, 59%–77%]; P = .6). One hundred twenty-four patients have undergone stage 2 reconstruction (78 modified Blalock–Taussig shunts and 46 right ventricle–pulmonary artery conduits). At the time of the stage 2 reconstruction, patients with right ventricle–pulmonary artery conduits were younger (153 days [range, 108–340 days]; modified Blalock–Taussig shunt, 176 days [range, 80–318 days]; P = .03), had lower systemic oxygen saturation (73% [range, 58%–85%] vs 77% [range, 57%–89%], P < .01), and had higher preoperative hemoglobin levels (15.8 g/dL [range, 13–21 g/dL] vs 14.8 g/dL [range, 12–19 g/dL], P < .01) compared with those of the modified Blalock–Taussig shunt group. By means of echocardiographic evaluation, there was a higher incidence of qualitative ventricular dysfunction in patients with right ventricle–pulmonary artery conduits (14/46 [31%] vs 9/73 [12%], P = .02). However, no difference was observed in common atrial pressure or the arteriovenous oxygen difference.ConclusionInterim analyses suggest no advantage of one shunt type over another. This report raises concern of late ventricular dysfunction and outcome in patients with a right ventricle–pulmonary artery conduit

Emerging Insights into the Pathophysiology of Multi-system Inflammatory Syndrome in Children Associated with COVID-19

Multisystem inflammatory syndrome in children (MIS-C) has emerged as a rare, delayed hyperinflammatory response to SARS-CoV-2 infection, and causes severe morbidity in the pediatric age group. While MIS-C shares many clinical similarities to Kawasaki disease (KD), important differences in epidemiologic, clinical, immunologic and potentially genetic factors exist and suggest potential differences in pathophysiology and points to be explored and explained. Epidemiologic features include male predominance, peak age of 6-12 years, and specific racial and/or ethnicity predilections. MIS-C is characterized by fever, prominent gastrointestinal symptoms, mucocutaneous manifestations, respiratory symptoms, and neurological complaints, and patients often present with shock. Cardiac complications are frequent and include ventricular dysfunction, valvular regurgitation, pericardial effusion, coronary artery dilation and aneurysms, conduction abnormalities, and arrhythmias. Emerging evidence regarding potential immunologic mechanisms suggest that an exaggerated T-cell response to a superantigen on the SARS-CoV-2 spike glycoprotein, as well as the formation of autoantibodies against cardiovascular, gastrointestinal, and endothelial antigens, are major contributors to the inflammatory milieu of MIS-C. Further studies are needed to determine both shared and distinct immunologic pathway(s) that underlie the pathogenesis of MIS-C versus both acute SARS-CoV-2 infcction and KD. There is evidence to suggest that the rare risk of more benign mRNA vaccine -associated myopericarditis is outweighed by a reduced risk of more severe MIS-C. In the current review, we synthesize the published literature to describe associated factors and potential mechanisms regarding an increased risk of MIS-C and cardiac complications, provide insights into the underlying immunologic pathophysiology, and define similarities and differences with KD

COVID-19 Positive Versus Negative Complete Kawasaki Disease: A Study from the International Kawasaki Disease Registry

To determine clinical differences for children with complete Kawasaki disease (KD) with and without evidence of preceding SARS-CoV-2 infection. From January 2020, contemporaneous patients with complete KD criteria were classified as either SARS-CoV-2 positive (KDCOVID+; confirmed household exposure, positive PCR and/or serology) or SARS-CoV-2 negative (KDCOVID-; negative testing and no exposure) and compared. Of 744 patients in the International Kawasaki Disease Registry, 52 were KDCOVID- and 61 were KDCOVID+. KDCOVID+ patients were older (median 5.5 vs. 3.7 years; p \u3c 0.001), and all additionally met diagnostic criteria for multisystem inflammatory syndrome in children (MIS-C). They were more likely to have abdominal pain (60% vs. 35%; p = 0.008) and headache (38% vs. 10%; p \u3c 0.001) and had significantly higher CRP, troponin, and BUN/creatinine, and lower hemoglobin, platelets, and lymphocytes. KDCOVID+ patients were more likely to have shock (41% vs. 6%; p \u3c 0.001), ICU admission (62% vs. 10%; p \u3c 0.001), lower left ventricular ejection fraction (mean lowest LVEF 53% vs. 60%; p \u3c 0.001), and to have received inotropic support (60% vs. 10%; p \u3c 0.001). Both groups received IVIG (2 doses in 22% vs. 18%; p = 0.63), but KDCOVID+ were more likely to have received steroids (85% vs. 35%; p \u3c 0.001) and anakinra (60% vs. 10%; p = 0.002). KDCOVID- patients were more likely to have medium/large coronary artery aneurysms (CAA, 12% vs. 0%; p = 0.01). KDCOVID+ patients differ from KDCOVID-, have more severe disease, and greater evidence of myocardial involvement and cardiovascular dysfunction rather than CAA. These patients may be a distinct KD phenotype in the presence of a prevalent specific trigger