Depending on geographic factors, cytomegalovirus (CMV) and toxoplasmosis are the more frequent intrauterine infections.
The pattern of brain involvement in CMV–IUI may range from minimal (small periventricular cysts, intrathalamic vasculopathy) to severe damage (brain atrophy, malformations of cortical development, hemorrhages).
Regardless the etiology, the prognosis is usually poor in the presence of intracranial findings.
CMV infected fetuses without brain findings are generally asymptomatic at birth but may develop sensorineural deafness.
In patients at risk, search systematically for signs of infection. Check the placenta, liver, intestines, and brain (ventriculomegaly, abnormal periventricular white matter, cysts, etc).
In low-risk patients, these signs may be the only clue for prenatal diagnosis.
The fetus may become infected with a variety of microrganisms through transplacental passage or as a result of ascending infection. In some patients, the infection may involve the central nervous system (CNS), causing lesions in different areas and of different grades of severity (Table 12–1).
Table 12–1.US CNS FINDINGS FOLLOWING INTRAUTERINE INFECTIONS ||Download (.pdf) Table 12–1. US CNS FINDINGS FOLLOWING INTRAUTERINE INFECTIONS
|Pathogen ||CNS involvement ||Reported in ||Ventriculomegaly ||Abnormal PVWM ||Calcifications ||Microcephaly ||Others |
|CMV ||Common ||Fetus, Infant ||Common ||Common ||Frequent ||Frequent ||MCD, CC, cerebellum, hemorrhage |
|Toxoplasma ||Common ||Fetus, Infant ||Common ||Rare ||Common ||Rare ||Hydranencephaly |
|Rubella ||Common ||Infant ||Rare ||Common ||Common ||Common ||– |
|Varicella-Zoster ||Extremely rare ||Fetus, infant ||Rare ||– ||Rare ||Rare ||Encephalitis, cerebellum, MCD |
|Herpes simplex ||Extremely rare ||Fetus, Infant ||Common ||Common ||Rare ||Rare ||Encephalitis |
|Parvovirus B19 ||Extremely rare ||Fetus, Infant ||Rare ||– ||– ||– ||Hemorrhage, stroke, MCD |
|Zika virus ||Common ||Fetus, Infant ||Common ||Common ||Common ||Common ||CC, cerebellum |
|LCMV ||Common ||Fetus, Infant ||Common ||Rare ||Common ||– ||– |
|West Nile virus ||Extremely rare ||Fetus, Infant ||– ||Rare ||– ||– ||Meningitis, encephalitis |
|Syphilis ||Extremely rare ||Fetus, Infant ||Rare ||Rare ||– ||Rare ||MCD |
|Trypanosoma ||Extremely rare ||Fetus, Infant ||– ||– ||– ||– ||Meningoencephalitis |
Cytomegalovirus (CMV) and Toxoplasma gondii are the most common pathogens affecting the brain. Other less common pathogens include, rubella virus,1 varicella-zoster virus,2 herpes simplex virus,3,4 parvovirus B19,5,6 Zika virus,7–9 Treponema pallidum,10 lymphocytic choriomeningitis virus,11 West Nile virus (WNV),12 Trypanosoma cruzi,13 and the nematode filaria.14
CMV is a large DNA virus with a wide infectious clinical spectrum ranging from subclinical to severe multisystem involvement; it is transmitted by direct contact with body fluids (saliva, tears, urine, blood, semen, and breast milk). Following maternal infection, CMV may cross the placenta and affect the fetus.
Herpesvirus 5, cytomegalic inclusion disease
Following the almost complete ...