Villitis of unknown etiology in the placenta of a pregnancy complicated by covid-19
Erdener Özer, Erkan Çağlıyan, Resmiye Irmak Yuzuguldu, Mustafa Cuneyt Cevizci, Nuray Duman
Abstract
Villitis of unknown etiology (VUE) is noninfectious chronic villitis thought to be associated with fetal growth restriction and stillbirth. COVID-19 and the pandemic SARS-CoV-2 infection can cause an increased risk in pregnant women for potential maternal and fetal complications from an immunological mechanism. We report a 39-week-gestational-age infant delivered to a 37-year-old mother diagnosed with SARS-CoV-2 infection at 37 weeks gestation. The placental examination showed the morphological features of VUE. We showed immunohistochemically that macrophages and CD4-positive T cells predominated in the villous tissue, although elevated numbers of CD8-positive cells were also present. We hypothesize that VUE may represent a maternal anti-viral immune response, in this case to SARS-CoV-2.