Objective To assess clinical characteristics and outcomes of severe acute respiratory syndrome coronavirus 2associated multisystem inflammatory syndrome in children (MIS-C). Study design Children with MIS-C admitted to pediatric intensive care units in New York City between April 23 and May 23, 2020, were included. Demographic and clinical data were collected. Results Of 33 children with MIS-C, the median age was 10 years; 61% were male; 45% were Hispanic/Latino; and 39% were black. Comorbidities were present in 45%. Fever (93%) and vomiting (69%) were the most common presenting symptoms. Depressed left ventricular ejection fraction was found in 63% of patients with median ejection fraction of 46.6% (IQR, 39.5-52.8). C-reactive protein, procalcitonin, d-dimer, and pro-B-type natriuretic peptide levels were elevated in all patients. For treatment, intravenous immunoglobulin was used in 18 (54%), corticosteroids in 17 (51%), tocilizumab in 12 (36%), remdesivir in 7 (21%), vasopressors in 17 (51%), mechanical ventilation in 5 (15%), extracorporeal membrane oxygenation in 1 (3%), and intra-aortic balloon pump in 1 (3%). The left ventricular ejection fraction normalized in 95% of those with a depressed ejection fraction. All patients were discharged home with median duration of pediatric intensive care unit stay of 4.7 days (IQR, 4-8 days) and a hospital stay of 7.8 days (IQR, 6.0-10.1 days). One patient (3%) died after withdrawal of care secondary to stroke while on extracorporeal membrane oxygenation. Conclusions Critically ill children with coronavirus disease-2019-associated MIS-C have a spectrum of severity broader than described previously but still require careful supportive intensive care. Rapid, complete clinical and myocardial recovery was almost universal.

Objective: To assess how a change in practice to more frequent use of high-flow nasal cannula for the treatment of bronchiolitis would affect the use of invasive devices in children. Design: Retrospective cohort study of children under 2 years old admitted to the ICU with respiratory failure secondary to bronchiolitis. Outcomes and invasive device use were compared between two time periods, before and after the practice change. Setting: Eighteen bed tertiary care PICU. Patients: A total of 325 children: 146 from 2010 to 2012 and 179 from 2015 to 2016. Interventions: None. Measurements and Main Results: There were no significant differences between the two time periods regarding gender, race/ethnicity, medical history, and viral profile, although children were younger in the earlier cohort (median age of 1.9 mo [interquartile range, 1.2–3.5] vs 3.3 mo [1.7–8.6]; p < 0.001). There was an increased use of noninvasive ventilation in the second time period (94% from 69%; p < 0.001), as well as a decreased frequency of intubation (13% from 42%; p < 0.001) and reduced central venous catheter placement (7% from 37%; p < 0.001). There was no significant difference in mortality between the two groups. A logistic regression analysis was conducted, which found that time period, intubation, and hospital length of stay were all independently associated with central venous catheter placement. Conclusions: A practice change toward managing patients with bronchiolitis in respiratory failure with less invasive means was associated with a reduction in the use of other invasive devices. In our cohort, minimizing the use of invasive ventilation and devices was not associated with an increase in mortality and could potentially have additional benefits.

Background Dengue virus (DENV) is endemic in many parts of the world. Antibody dependent enhancement (ADE) in DENV infections occurs when a person with primary immunity is infected by a second, different DENV strain. Antibodies to Zika virus (ZIKV), which emerged in the Western Hemisphere in 2015, are cross reactive with DENV and theoretically could provoke ADE in a DENV naïve individual. Case presentation DENV infection was suspected in a child who had recently returned from a one-month stay in the Dominican Republic. The child presented with fever, vomiting, abdominal pain, and in hypovolemic shock. Volume and pressor resuscitation were unsuccessful, and the child died less than 24 h after hospitalization. Laboratory results suggested an early acute first DENV infection since serum, plasma, and spinal fluid had DENV1 detected by polymerase chain reaction (PCR), yet the serum lacked IgG antibodies to DENV nonstructural protein 1 (NS1) of all four DENV serotypes. This acute DENV infection occurred in the presence of a remote ZIKV infection as determined by antibodies to ZIKV NS1 envelope by multiplex microsphere immunoassay and an exceptionally high plaque reduction neutralization titer to ZIKV. ZIKV IgG avidity index was high, confirming a past infection. DENV1 RNA was detected in all ten organs and tissues examined by PCR. The severe and fatal complications reported here suggest that a remote ZIKV infection may provoke an exaggerated immune response leading to hypovolemic shock when primarily infected by DENV1. Conclusion We report the first known patient in the United States with a rapidly progressive and fatal case of travel-associated DENV in which prior exposure to ZIKV likely played a role in triggering an ADE phenomenon. This association of prior ZIKV immunity and subsequent new dengue infection is a worrisome phenomenon and an important contribution to the body of knowledge on immunity to flaviviruses.