PIMS-TS immunophenotype: description and comparison with healthy children, Kawasaki disease and severe viral and bacterial infections.

BACKGROUND: A new clinical syndrome named Paediatric Inflammatory Multisystem Syndrome Temporally Associated with SARS-CoV-2 (PIMS-TS) has been described. This new disease is a leading cause of hospital and paediatric intensive care unit (PICU). It has been related to immunity dysregulation. METHODS: Prospective-retrospective observational study to describe the innate cell signature and immunophenotype of children admitted to PICU because of PIMS-TS (from March 2020 to September 2020). The immunophenotype was done through the expression analysis of these proteins of mononuclear cells: CD64, CD18, CD11a and CD11b. They were compared with previous healthy controls and children admitted to PICU because of bacterial infection, viral infection and Kawasaki disease (KD). Two hundred and forty-seven children were studied: 183 healthy controls, 25 viral infections, 20 bacterial infections, 6 KD and 13 PIMS-TS. RESULTS: PIMT-TS showed the lowest percentage of lymphocytes and monocytes with higher relative numbers of CD4+ (p = .000). Monocytes and neutrophils in PIMS-TS showed higher levels of CD64 expression (p = .000). Also, CD11a and CD11b were highly expressed (p =,000). CONCLUSION: We observed a differential cell innate signature in PIMS-TS. These findings are consistent with a proinflammatory status (CD64 elevated expression) and lymphocyte trafficking to tissues (CD11a and CD11b). More studies should be carried out to confirm our results.

Shock and Myocardial Injury in Children With Multisystem Inflammatory Syndrome Associated With SARS-CoV-2 Infection: What We Know. Case Series and Review of the Literature.

BACKGROUND: Multisystem inflammatory syndrome associated with SARS-CoV-2 infection can lead to myocardial injury and shock in children, likely the result of a severe inflammatory state, and can mimic Kawasaki disease. OBJECTIVE: To describe the characteristics of shock and myocardial injury in children with confirmed or suspeted COVID-19 during the SARS-CoV-2 pandemic in Spain, including clinical presentation, laboratory and imaging findings, treatment, disease course, and outcome. An extensive literature review is provided. METHODS: Retrospective case series including all children (age 1 month-18 years) admitted to a pediatric intensive care unit in Madrid, Spain, between March 15 and April 30, 2020 with suspected or confirmed SARS-CoV-2 infection and shock. RESULTS: Twelve previously healthy patients with shock, age 5 to 14 years, were included. All required volume resuscitation and 75% required vasoactive/inotropic support. Distributive shock was present on admission in 67% (n = 8), and 4 patients (33%) showed features of cardiogenic shock. Myocardial injury was diagnosed in 67% (n = 8) and ventricular dysfunction in 33% (n = 4). The most common symptoms on presentation were fever (100%), anorexia (100%), diarrhea (75%), and vomiting (75%). Five patients showed signs of Kawasaki disease but none met the criteria for the classic form. Laboratory findings revealed lymphopenia (83%), thrombocytopenia (83%), and increased inflammatory markers (100%). Respiratory status was not significantly impacted. Chest X-ray showed bilateral alveolar infiltrates in 7 (58%) and bilateral pneumonia in 3 (25%). COVID-19 was confirmed in 11 cases (92%). All received empirical therapy against COVID-19, thromboprophylaxis and immunomodulation. Median stay in the PICU and inpatient ward was 4.5 and 10 days, respectively. No patients died. CONCLUSION: Multisystem inflammatory syndrome in children with COVID-19 can mimic Kawasaki disease and lead to a combination of distributive and cardiogenic shock, probably secondary to a hyperinflammatory state that remains to be precisely defined. Treatment strategies include hemodynamic support, empirical therapies against COVID-19, thromboprophylaxis, and immunomodulation.

Severe SARS-CoV-2 Infection in Children With Suspected Acute Abdomen: A Case Series From a Tertiary Hospital in Spain.

We describe 5 children with severe SARS-CoV-2 infection, hemodynamic instability and suspected acute abdomen. This form of the disease has not been previously documented. Four of the cases were confirmed SARS-CoV-2 infection and 1 probable. All of them were previously healthy and needed a pediatric critical care unit admission. The respiratory symptoms were not dominant or were absent. Also, fever was observed. Laboratory testing revealed lymphopenia and high levels of C-reactive protein and procalcitonin with D-dimer, ferritin and interleukin-6 usually elevated. Respiratory support and inotropic support were almost always necessary. In all of them, deterioration occurred on the day of admission.

Children in Critical Care Due to Severe Acute Respiratory Syndrome Coronavirus 2 Infection: Experience in a Spanish Hospital.

OBJECTIVES: Spain has been one of the countries most severely affected by the coronavirus disease 2019. This study aims to describe a series of children admitted to a PICU due to coronavirus disease 2019 infection. DESIGN: Prospective observational study. SETTING: Tertiary hospital in Madrid, Spain. PATIENTS: Children admitted to the PICU with severe acute respiratory syndrome coronavirus 2 (severe acute respiratory syndrome coronavirus 2) infection, from March 1, 2020, to April 15, 2020. INTERVENTIONS: Observational study. MEASUREMENTS AND MAIN RESULTS: Epidemiologic data, previous clinical characteristics, support therapy needed, imaging tests, laboratory observations on admission, and pharmacologic therapy. Eleven children were admitted to the PICU, with suspected coronavirus disease 2019; the polymerase chain reaction test was positive in seven. The median age was 100.7 months (range, 0.5-162). Five were admitted from the emergency department and two from the ward. The Pediatric Sequential Organ Failure Assessment score was 3 (range, 0-9), and Pediatric Risk of Mortality II score was 4 (range, 0-16). All children were previously healthy except one (allogeneic hematopoietic stem cell transplantation). Respiratory symptoms and fever were prevalent. A chest radiograph led to a pneumonia diagnosis. Not all patients presented with lymphopenia on admission. D-Dimer and ferritin were elevated. All patients needed oxygen therapy through a nasal cannula; five patients received high-flow nasal cannula therapy, which was later substituted with noninvasive ventilation in four. Mechanical ventilation was necessary in two patients on the first day of PICU admission. Two children required mechanical ventilation and inotropic support. Tocilizumab was applied in two intubated children. Also, four children received heparin. No patients died. CONCLUSIONS: On the whole, the children were previously healthy and are more than 1 year old. Respiratory symptoms were the leading cause of PICU admission, making respiratory support the principal therapy. Patients requiring mechanical ventilation showed deterioration on the first day of admission. These children seemed to require close monitoring, and multicenter studies are necessary.