Myocarditis in children after COVID-19 vaccine.

Three healthy adolescents presented with myocarditis confirmed on cardiac magnetic resonance imaging after receiving Pfizer-BioNTech COVID-19 vaccine. All patients were hemodynamically stable and had good short-term outcomes. Long-term outcomes are yet to be determined. Larger studies are needed to determine whether an association between Pfizer-BioNTech COVID-19 vaccine and myocarditis exists.

Not just vegetations: focal myocardial changes in patients with fungal infections.

BACKGROUND: Fungal endocarditis classically involves dense heterogenous vegetations. However, several patients with fungal infections were noted to have myocardial changes ranging from focal brightening to nodular thickening of chordae or papillary muscles. This study evaluates whether these findings are associated with fungal infections. METHODS: In a retrospective case-control study, paediatric inpatients with fungal infections (positive blood, urine, or catheter tip culture) in a 5-year period were matched 1:1 to inpatients without positive fungal cultures. Echocardiograms were scored on a 5-point scale by two independent readers for presence of myocardial brightenings, nodular thickenings, and vegetations. Clinical data were compared. RESULTS: Of 67 fungal cases, positive culture sites included blood (n = 44), vascular catheter tip (n = 7), and urine (n = 29); several had multiple positive sites. "Positive" echo findings (score ≥ 2+) were more frequent in the Fungal Group (33 versus 18%, p = 0.04). Fungal Group patients with "positive" versus "negative" echo findings had similar proportion of bacterial infections. Among fungal cases, those with "positive" echo findings had longer hospital length of stay than cases with "negative" echos (median 58 versus 40 days, p = 0.03) but no difference in intensive care unit admission, extracorporeal membranous oxygenation support, or mortality. CONCLUSIONS: Myocardial and papillary muscle brightening with nodular thickening on echocardiogram appear to be associated with fungal infections. There may be prognostic implications of these findings as patients with "positive" echo have longer length of stay. Further studies are needed to better understand the mechanism and temporal progression of these changes and determine the prognostic value of this scoring system.

Long-Term Outcomes After Surgical Pulmonary Arterioplasty and Risk Factors for Reintervention.

BACKGROUND: Although surgical patch arterioplasty is the conventional therapy for branch pulmonary artery (PA) stenosis, limited data exist on long-term outcomes. We examined the incidence of and risk factors for reintervention after surgical arterioplasty for branch PA stenosis in biventricular congenital heart disease. METHODS: This retrospective cohort study included patients with 2-ventricle physiology who underwent patch arterioplasty for PA stenosis at a single high-volume congenital heart center during a 10-year period. Freedom from surgical or percutaneous reintervention for recurrent PA stenosis was evaluated. Univariate and multivariable Cox regression analyses were performed to determine risk factors for reintervention. RESULTS: Among 135 patients, the median age at patch arterioplasty was 0.9 years. Survival to hospital discharge (or 30 days postoperatively) was 96%. During a median follow-up period of 4.0 years, reintervention for PA stenosis occurred in 38 of 115 patients (33%) at a median time to reintervention of 1.4 years. The overall 10-year reintervention rate was 54%. In univariate analysis, age less than 30 days at initial arterioplasty, congenital PA stenosis (vs acquired), and bilateral PA stenosis (vs unilateral) were significantly associated with reintervention. In multivariable analysis, neonatal age (adjusted hazard ratio, 3.6; p = 0.002) and bilateral PA stenosis (adjusted hazard ratio, 2.8; p = 0.005) remained independently associated with reintervention. CONCLUSIONS: Long-term reintervention for recurrent PA stenosis after patch arterioplasty is common. Patients with bilateral PA stenosis or age younger than 30 days at the time of the index pulmonary arterioplasty are at higher risk for reintervention. These patients may benefit from frequent monitoring or novel approaches to repair.

Differential impact of the CD45 juxtamembrane wedge on central and peripheral T cell receptor responses.

The cooperative activity of protein tyrosine kinases and phosphatases plays a central role in regulation of T cell receptor (TCR) signal strength. Perturbing this balance, and thus the threshold for TCR signals, has profound impacts on T cell development and function. We previously generated mice containing a point mutation in the juxtamembrane wedge of the receptor-like protein tyrosine phosphatase CD45. Demonstrating the critical negative regulatory function of the wedge, the CD45 E613R (WEDGE) mutation led to a lymphoproliferative disorder (LPD) and a lupus-like autoimmune syndrome. Using genetic, cellular, and biochemical approaches, we now demonstrate that the CD45 wedge influences T cell development and function. Consistent with increased TCR signal strength, WEDGE mice have augmented positive selection and enhanced sensitivity to the CD4-mediated disease experimental autoimmune encephalitis (EAE). These correspond with hyperresponsive calcium and pERK responses to TCR stimulation in thymocytes, but surprisingly, not in peripheral T cells, where these responses are actually depressed. Together, the data support a role for the CD45 wedge in regulation of T cell responses in vivo and suggest that its effects depend on cellular context.