Intrauterine latent herpes simplex virus infection: II. Latent neonatal infection.

Herpes simplex virus (HSV, probably type 2) antigen has been detected in endometria and abortion tissue (companion paper) and in placentae, umbilical cords, and fetal and neonatal organs by avidin-biotin complex immunohistochemical studies. HSV cytologic abnormalities were not detected in any of the 12 normal and 64 abnormal cases analyzed, nor was HSV detected by culture or electron microscopy in selected cases. Antigen was present in single epithelial and, rarely, mesenchymal cells of various organs. Clinically unexplained fetal or neonatal problems associated with HSV antigen positivity included intrauterine death, fetal growth retardation, cystic brain degeneration, hydrops, interstitial pneumonitis, necrotizing enterocolitis, hepatitis, encephalitis, myocarditis, and renal failure. Maternal floor infarct of placenta and calcifying funisitis are the manifestations of intrauterine HSV infection in most cases. Maternal history of HSV infection was uncommon. It is concluded that intrauterine HSV infection may persist in the fetus and neonate in a latent fashion without cytologic abnormalities or detectable virus. This latent infection may be associated with intrauterine and neonatal death, organ damage, and neonatal disease.