Initial data from COVID-19 patients suggests that one of the primary causes of death is significant endothelial injury leading to blood clotting and impaired multiorgan microvascular perfusion. The current study uses a safe, convenient bedside imaging tool called contrast-enhanced ultrasound (CEUS) to estimate the extent of microvascular perfusion impairment in the heart, kidneys and/or brain of COVID-19 pediatric patients in vivo and assess the significance of imaging findings by correlating to clinical outcomes.

This pilot study will be conducted at one site, The Children's Hospital of Philadelphia. The investigators plan to enroll and evaluate 30 patients.

The current study uses a safe, convenient bedside imaging tool called contrast-enhanced ultrasound (CEUS) to measure the extent of microvascular perfusion impairment in the heart, kidneys and/or brain of COVID-19 pediatric patients and, as exploratory analysis, to assess the significance of imaging findings by correlating to clinical outcomes.

Sulfur hexafluoride lipid-type A microspheres (LumasonTM, Bracco Inc) is an FDA-approved ultrasound contrast agent. Contrast-enhanced ultrasound scan with a duration of approximately 15 minutes will be performed when a COVID-19 diagnosis has been made (or is highly suspected) according to established clinical procedures. One CEUS will be performed per patient, with up to 2 intravenous injections of the contrast agent. The dosing plan will be weight-adjusted, based on a dose of 0.03 mL/kg (with a maximum dose of 2.4 mL per injection). Organ perfusion will be evaluated in the heart, kidneys, and/or brain. Clinical outcomes during hospital stay will be collected for correlation to CEUS-based measures.

Inclusion Criteria:

1. Patient (male/female) hospitalized at the Children's Hospital of Philadelphia (CHOP).
2. Patient 17 years of age or younger.
3. Diagnosis of COVID-19 or high clinical suspicion for COVID-19 despite negative tests (according to the definition of probable case by the European Centre for Disease Prevention and Control).
4. Patients have evidence of cardiovascular compromise, myocardial injury, acute kidney injury and/or new-onset neurological symptoms.
5. Parental/guardian permission (informed consent)

Exclusion Criteria:

1. Medical history of Lumason hypersensitivity

15 minutes.

Since this is an exploratory study with limited sample size, no absolute conclusions related to true microvascular impairment in MIS-C can be drawn. Whether heterogeneous results are due to the small sample, the timing of CEUS with regard to disease evolution and treatment, the use of concomitant medications, such as furosemide, a milder course of the disease, or the differing pathophysiology between MIS-C and primary COVID-19 infection in adults requires additional exploration.