Distinct phenotypes of multisystem inflammatory syndrome in children: a cohort study

Longitudinal Cardiac Evaluation of Children with Multisystem Inflammatory Syndrome (MIS-C) Following COVID-19 by Conventional and Speckle-Tracking Echocardiography

Multisystem inflammatory syndrome in children (MIS-C), is a rare but severe, hyperinflammatory complication of COVID-19, in which cardiovascular abnormalities are frequently detected. In this prospective study, we describe the echocardiographic findings in patients with MIS-C, with the use of conventional Echocardiography and Speckle-Tracking Echocardiography (STE) with Left Ventricular (LV) Global Longitudinal Strain (GLS) analysis, in the acute and follow-up phase. In total, 25 MIS-C patients [64% females, mean (± SD) age: 8.3 (± 3.72) years] were included. In the acute phase, median (IQR) Troponin and NT-proBNP and mean heart rate, were 8.07 (14.52) pg/mL, 2875.00 (7713.00) pg/mL, and 102.87 (± 22.96) bpm, respectively. Median (IQR) LV Ejection Fraction (LVEF) was 66 (8)% and LVEF impairment was detected in 2/25 (8%) patients. On follow-up (mean time interval:9.50 ± 4.59 months), heart rate was significantly lower, with a mean value of 90.00 (± 14.56) bpm (p-value = 0.017). Median (IQR) LVEF was 66.00 (6.70)% (p-value = 0.345) and all 25 participants had normal LVEF. In 14/25 patients, additional LV-GLS analysis was performed. During the acute phase, mean LV-GLS was - 18.02 (± 4.40)%. LV-GLS was abnormal in 6/14 patients (42.9%) and among them, only one patient had reduced LVEF. On follow-up (median (IQR) time interval:6.93 (3.66) months), mean LV-GLS was -20.31 (± 1.91)% (p-value = 0.07) and in 1/14 patient (7.1%), the LV-GLS impairment persisted. In conclusion, in the acute and follow-up phase, we detected abnormal LV-GLS values in some patients, in the presence of normal LVEF, indicating that STE-GLS is a valuable tool for identifying subclinical myocardial injury in MIS-C.

Pediatric neuroimaging findings and clinical presentations of COVID-19: A systematic review

OBJECTIVES

Symptoms from SARS-CoV-2 infection can involve multiple organ systems. Several reviews discussed the neurologic involvement and neuroimaging findings in adults but research on children is lacking. This study aimed to analyze the incidence of neurologic involvement in patients diagnosed with pediatric inflammatory multisystem syndrome temporally associated with COVID-19 (PIMS-TS) or multisystem inflammatory syndrome in children (MIS-C); and also to summarize current literature on possible neuroimaging findings in SARS-CoV-2 infected children.

METHODS

A literature search in six electronic databases was performed to retrieve case series, cohort studies, and cross-sectional studies on neurologic involvement in COVID-19 patients younger than 21 years of age published between December 2019 to September 2023, including COVID-19 patients.

RESULTS

A total of 2224 patients with MIS-C from 10 cohorts and cross-sectional studies suggested that neurologic involvement in these subsets ranges from 8.5% to 32.1%. Symptoms included acute encephalitis, seizures, stroke, cranial nerve palsy, nausea/vomiting, and intracranial hypertension. Neuroradiology findings of 114 children from 50 case reports included splenial or acute disseminated encephalomyelitis (ADEM)-like lesions, cytotoxic brain edema, autoimmune demyelinating diseases, ischemic stroke and arteritis, venous thrombosis, intracranial hemorrhage, meningitis, posterior reversible encephalopathy syndrome, anti-N-methyl-D-aspartate receptor autoimmune encephalitis, acute hemorrhagic leukoencephalitis, hydrocephalus, olfactory bulb atrophy, cerebellitis, and acute necrotizing encephalitis.

CONCLUSION

Radiologic findings of SARS-CoV-2 infection in the pediatric population are diverse. Neuroimaging studies should be considered in critically ill patients to rule out neurologic involvement and facilitate early interventions.

Infection, Dysbiosis and Inflammation Interplay in the COVID Era in Children

For over three years, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in children and adolescents has generated repercussions, especially a few weeks after infection, for symptomatic patients who tested positive, for asymptomatic ones, or even just the contacts of an infected person, and evolved from severe forms such as multisystem inflammatory syndrome in children (MIS-C) to multifarious clinical manifestations in long COVID (LC). Referred to under the umbrella term LC, the onset of persistent and highly heterogeneous symptoms such as fatigue, post-exertion malaise, cognitive dysfunction, and others have a major impact on the child's daily quality of life for months. The first aim of this review was to highlight the circumstances of the pathophysiological changes produced by COVID-19 in children and to better understand the hyperinflammation in COVID-19 and how MIS-C, as a life-threatening condition, could have been avoided in some patients. Another goal was to better identify the interplay between infection, dysbiosis, and inflammation at a molecular and cellular level, to better guide scientists, physicians, and pediatricians to advance new lines of medical action to avoid the post-acute sequelae of SARS-CoV-2 infection. The third objective was to identify symptoms and their connection to molecular pathways to recognize LC more easily. The fourth purpose was to connect the triggering factors of LC with related sequelae following acute SARS-CoV-2 injuries to systems and organs, the persistence of the virus, and some of its components in hidden reservoirs, including the gut and the central nervous system. The reactivation of other latent infectious agents in the host's immune environments, the interaction of this virus with the microbiome, immune hyperactivation, and autoimmunity generated by molecular mimicry between viral agents and host proteins, could initiate a targeted and individualized management. New high-tech solutions, molecules, probiotics, and others should be discovered to innovatively solve the interplay between RNA persistent viruses, microbiota, and our immune system.