Fetal Effect Of HCMV Infection And Its Diagnosis And Management

HCMV is the most frequent congenital infection and may cause serious results. Congenital cytomegalovirus infection is a common cause of mental and hearing impairments. HCMV infection is rather common in population, which usually cause latent infection in most cases. But if it happened during pregnancy, it could cause vertical transmission and fetal handicaps.Compared with women with recurrent infection, women with primary infection had statistically significant higher prevalence of fever, asthenia, headache, rhino-pharyngo-tracheo-bronchitis, myalgia and malaise, elevated aspartate aminotransferase and/or alanine aminotransferase levels, and lymphocytosis. The diagnosis of maternal infection mainly relies on laboratory methods, such as the detections of HCMV-specific antibody and its avidity, antigens, DNA and mRNA, or virus culture. Both maternal primary and recurrent infection can lead to intrauterine infection of the fetus, but the primer has higher risk of fetal infection and worse outcome. Serologic screening for HCMV infection is a debated issue, and it's not recommended in most countries.In cases of suspected fetal infection, such as maternal primary infection or ultrasound abnormalities, prenatal diagnosis should be made by villus biopsy, amniocentesis and cordocentesis. Amniotic fluid (AF) is the most appropriate material for prenatal diagnosis. AF should be sampled after 21st week of gestation and at least 5-6 weeks after the estimated onset of infection. Fetal infection is confirmed when viral DNA is detected or positive viral culture result. AF viral load is correlated with fetal prognosis. Fetal blood sampling by cordocentesis does not give any additional diagnostic value, and should only be considered as part of the prognostic evaluation but not for diagnostic purpose. What's more, ultrasound and magnetic resonance image (MRI) are of great prognostic value. By prenatal diagnosis procedures, fetal infection can be confirmed, but symptomatic congenital infection cannot be figured out precisely. Antenatal procedures involve risks of infection and miscarriage. And the risk of HCMV transmitted by the procedures is small. Prenatal diagnosis is also a debated issue, people hold different opinions upon it.About 12.5% of congenitally infected newborns will show manifestations of infection, including hepatosplenomegaly, jaundice, petechiae or purpura, pneumonia, intrauterine growth restriction(IUGR), Chorioretinitis, neural degeneration disease, et al. Permanent seguelae include microcephaly, visual impairment, hearing loss, mental retardation, motor deficit, epilepsy, even death. Postnatally detection of HCMV in newborns will ascertain the prenatal diagnosis.For congenital cytomegalovirus infection, termination of pregnancy is indicated, and there is no therapeutic option available except for clinical trials. Despite promising results of HIG and antiviral drugs, current treatment options for fetal infection are very limited. Studies in newborns show the effectiveness of antiviral treatment of symptomatic congenital infection. For patients of confirmed congenital infection, doctors should assess the risk of long permanent sequelae and discuss different management options, and let themselves make the choice. Vaccines will be the most effective methods for prevention, and many are under preclinical or clinical trials. Pending the availability of an active vaccine, hygiene intervention may be an important way for the prevention.