PC1179: Newborn Born with Nonimmune Hydrops Fetalis and Dilated Coronary Arteries to a Mother with Suspected sars-cov-2 Infection During Pregnancy

Introduction: We describe a case of an infant presenting with nonimmune hydrops fetalis (NIHF), who was found to have coronary artery dilatation (CAD). While NIHF is a known sequelae of maternal intrauterine infections, cases are not typically associated with CAD. Given this finding and maternal history suggestive of SARS-CoV-2 illness prenatally, multi-system inflammatory syndrome in neonates (MIS-N), which has been reported in the literature, was included in the differential diagnosis for NIHF.

Case Description: A 36-week male infant presented upon referral to tertiary NICU with NIHF defined at delivery. He developed respiratory failure and hypoxemia suggestive of pulmonary hypertension (PPHN) and echocardiogram showed diffuse CAD (figure 1) prompting exploration of a possible SARS-CoV-2 exposure in utero. Infant SARS-CoV-2 IgG was positive. Further history revealed that mother had symptoms including body aches, headaches, anosmia, and aguesia at 15-weeks gestation. Mother was not tested for SARS-CoV-2 at that time, and further history indicated she was not vaccinated for SARS-CoV-2. Elevation in inflammatory markers in the infant including c-reactive protein (3.5mg/dl), lactate dehydrogenase (3,639u/L), ferritin (420ng/ml), and D-dimer (5,478ng/ml) were noted, along with elevated pro-B-type natriuretic peptide (>70,000pg/ml) and troponin (0.1ng/ml). Patient also had thrombocytopenia (39,000), anemia (25.9) and elevated aspartate transaminase (236u/liter) and alanine transaminase (194u/liter). Although infant ParvoB19 IgG was positive, symptomatology was less specific and CAD is not typically associated with this congenital infection. The remainder of NIHF workup was negative (table 1A). With CAD, one might consider Kawasaki Disease, however, infant was never febrile nor did he have mucocutaneous manifestations. Based on age, seropositivity for SARS-CoV-2 IgG, severe illness with multi-organ involvement, laboratory evidence of inflammation and lack of definitive explanation, the infant was treated for presumed MIS-N. The infant received intravenous immunoglobulin (1gram/kg/dose daily for 2 days) and intravenous dexamethasone (0.3mg/kg/dose tapered over 10 days) with improvement in clinical and respiratory status followed by slow improvement in inflammatory markers and eventual resolution of CAD (table 1B). Clinical course was complicated by coagulopathy with intraventricular hemorrhage, thus antithrombotic therapy was not administered.

Discussion: We report a case of a neonate presenting with NIHF and CAD born to a mother with history of possible maternal second trimester SARS-CoV-2 infection prompting treatment for MIS-N. Cases of MIS-N secondary to maternal SARS-CoV-2 infection have been infrequently reported in the literature. On review of current literature describing MIS-N, most cases present with respiratory distress or cardiovascular dysfunction, although presentation is variable. Proposed diagnostic criteria and treatment guidelines have been created through review of case reports that are based on the criteria for MIS-C in older children.

Conclusion: This is a case reported of an infant with NIHF and CAD. In light of positive SARS-CoV-2 antibody, MIS-N, a rare diagnosis and one of exclusion, may be a consideration.