EXCLUSION CRITERIA
Neonates in which SARS-CoV-2 antibodies were present but the clinical presentation was not suggestive of multisystem nature were excluded.
Methodology: Cohort of MISN cases was subdivided based on the timing of presentation , to differentiate the possible source of SARS- CoV-2antibodies:
1. Early MISN (within 1st 72 h of life) — hypothesized as presenting due to transplacental transfer of maternal SARS-CoV-2antibodies.
2. Late MISN (more than 72 h of life) — hypothesized as occurring either due to antibodies produced secondary to SARS-CoV-2infection in the new born or transplacental transfer of maternal SARS-CoV-2 antibodies.
The following data was collected in reported cases in pre-defined structured proforma:
  1. Birth gestation, weight, etc.
  2. Serology: maternal and neonatal Serology for SARS- CoV-2 — both antigen and antibodies to ascertain the mode of transmission
  3. Clinical features and laboratory results
  4. Management and outcomes
Age-specific normal ranges were used for analysis of laboratory investigations. Deranged values were defined as serum Ferritin values of>260ng/ml in term newborn and >200ng/ml in preterm [23], D-dimer>2000ng/ml, ProB-type natriuretic peptide (pro-BNP)>700pg/ml, and serum lactate dehydrogenase >450U/l [24]. Echocardiogram (ECHO) was performed to look for abnormal coronary dilatation and cardiac dysfunction/contractility. Cardiac dysfunction or myocarditis on ECHO was considered when left ventricular (LV) ejection fraction (EF) is decreased <55% and fractional shortening (FS) <26% on functional echocardiography [25]. Parental consent was obtained from each case. Institutional Ethics committee, approval was taken.