Histological findings in foetuses congenitally infected by cytomegalovirus.

BACKGROUND: Congenital cytomegalovirus (CMV) infection is a major cause of central nervous system damage leading to sensorineural hearing loss, mental retardation and cerebral palsy.

OBJECTIVES: Identify the type of organ involvement and understand the histopathogenesis of damage in foetuses of women with a CMV-highly positive amniotic fluid.

STUDY DESIGN: 34 foetuses with congenital CMV infection documented by prenatal diagnosis were studied. Three foetuses died in utero. The remaining pregnancies were electively terminated at 20-21 weeks gestation.

RESULTS: Foetal organs positive for CMV antigens were: placenta (100%), pancreas (100%), lung (87%), kidney (87%), liver (71%), brain (55%) and heart (44%). Inflammatory infiltrate was almost always present in CMV-infected foetal organs and the severity of the inflammatory response was correlated with the organ damage. Brain damage with necrosis was observed in 33% (9/27) and a mild telencephalic leukoencephalopathy in 22% (6/27) of foetuses studied.

CONCLUSIONS: Focal necrosis was observed very frequently in organs such as pancreases, livers, hearts and kidneys. However the damage in these organs is likely to be resolved by parenchymal regeneration. Brain damage, which seems to be the results of a combined effect of viral infection, inflammatory infiltration and hypoxia due to severe placentitis, is less likely to be resolved because of the low regeneration ability of this organ.