Co-occurrence of Eosinophilic/T-Cell Chorionic Vasculitis and Acute Chorionitis, Acute Chorionic Vasculitis, and...

Eosinophilic/T-cell chorionic vasculitis was initially defined as "a new form of chorionic vasculitis characterized by an infiltrate composed primarily of eosinophils and CD3⁺ T lymphocytes ... [that] occurs in the absence of any evidence of chorioamnionitis." No subsequent reports have directly addressed whether histologic evidence suggestive of amniotic fluid infection should preclude its diagnosis. The case reported here describes a term placenta with mild acute chorionitis, moderate acute subchorionitis, mild acute chorionic vasculitis, and funisitis associated with multifocal eosinophilic/T-cell chorionic vasculitis. It shows unequivocally, with immunohistochemical staining, that eosinophilic/T-cell chorionic vasculitis and acute chorionic vasculitis can be seen and histologically distinguished in the same case. The paper shows how differing interpretations of inclusion and exclusion criteria by investigators have affected estimates of the incidence of this rare lesion. There is a need to harmonize diagnostic criteria; the report describes how cases with both entities can be documented carefully.