Background – There is a paucity of data describing the effects of COVID-19, especially in asymptomatic patients, on placental pathology. Although the pathophysiology of COVID-19 is not completely understood, there is emerging evidence that it causes a severe systemic inflammatory response and results in a hypercoagulable state with widespread microthrombi. We hypothesized that it is plausible that a similar disease process may occur in the fetal-maternal unit. Objective – The aim of this study was to determine whether COVID-19 in term patients admitted to Labor and Delivery, including women without COVID-19 symptomatology, is associated with increased placental injury compared to a cohort of COVID-19 negative controls. Study Design – This was a retrospective cohort study performed at NYU Winthrop Hospital between 3/31/2020 and 6/17/2020. During the study period all women admitted to Labor and Delivery were routinely tested for SARS-CoV-2 regardless of symptomatology. The placental histopathological findings of COVID-19 patients (n=77) who delivered a singleton gestation at term were compared to a control group of term patients without COVID-19 (n=56). Controls were excluded if they had obstetric or medical complications including fetal growth restriction, oligohydramnios, hypertension, diabetes, coagulopathy or thrombophilia. Multivariable logistic regression models were performed for variables that were significant in univariable analyses. A subgroup analysis was also performed comparing asymptomatic COVID-19 cases to negative controls. Results – In univariable analyses, COVID-19 cases were more likely to have evidence of fetal vascular malperfusion, i.e. presence of avascular villi and/or mural fibrin deposition (32.5% (25/77) vs. 3.6% (2/56), p<0.0001) and villitis of unknown etiology (20.8% (16/77) vs. 7.1% (4/56), p=0.030). These findings persisted in a subgroup analysis of asymptomatic COVID-19 cases compared to COVID-19 negative controls. In a multivariable model adjusting for maternal age, race/ethnicity, mode of delivery, preeclampsia, fetal growth restriction and oligohydramnios, the frequency of fetal vascular malperfusion abnormalities remained significantly higher in the COVID-19 group (OR= 12.63, 95% CI [2.40, 66.40]). While the frequency of villitis of unknown etiology was more than double in COVID-19 cases compared to controls, this did not reach statistical significance in a similar multivariable model (OR=2.11, 95% CI [0.50, 8.97]). All neonates of mothers with COVID-19 tested negative for SARS-CoV-2 by PCR. Conclusions – Despite the fact that all neonates born to mothers with COVID-19 were negative for SARS-CoV-2 by PCR, we found that COVID-19 in term patients admitted to Labor and Delivery is associated with increased rates of placental histopathologic abnormalities, particularly fetal vascular malperfus...

Accumulating evidence demonstrates that the intestinal microbiota enhance mammalian enteric virus infections. For example, we and others have previously reported that commensal bacteria stimulate acute and persistent murine norovirus infections. In apparent contradiction to these results however, the virulence of murine norovirus infection was unaffected by antibiotic treatment. This prompted us to perform a detailed investigation of murine norovirus infection in microbially deplete mice, revealing a more complex picture whereby commensal bacteria inhibit viral infection of the proximal small intestine while simultaneously stimulating infection of distal regions of the gut. Thus, commensal bacteria can regulate viral regionalization along the intestinal tract. We further show that the mechanism underlying bacteria-dependent inhibition of norovirus infection in the proximal gut is bile acid priming of type III interferon. Finally, the regional effects of the microbiota on norovirus infection may result from distinct regional expression profiles of key bile acid receptors which regulate the type III interferon response. Overall, these findings reveal that biotransformation of host metabolites by the intestinal microbiota directly and regionally impacts infection by a pathogenic enteric virus.

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Numerous abdominal and pelvic imaging findings are seen in Burkitt lymphoma affecting the gastrointestinal tract and solid organs. Recognition of the common and uncommon imaging findings is essential in the diagnosis and treatment of patients with Burkitt lymphoma because prompt therapy is critical.