Chronic villitis is a common condition in human placentae. In some cases an
infectious cause can be demonstrated, such as infection with cytomegalovir
us and rubella virus. Most often it is of unknown aetiology, the so-called
VUE (villitis of unknown aetiology). We describe two cases with identificat
ion of specific infectious agents, each demonstrating previously unreported
findings, i.e. persistent varicella antigen in the villi in case 1, and pr
esence of toxoplasma cysts in Wharton's jelly in case 2. The identification
of the pathogens, varicella virus and toxoplasma, would easily have been o
verlooked in routine study of the placenta and were possible because of cli
nical suspicion. (C) 1999 W. B. Saunders Company Ltd.