Several fetal abnormalities associated with CMV infection may be seen with sonography, computed tomography, or magnetic resonance imaging. In some cases, they are found at the time of routine prenatal sonographic screening, but in others they are part of a specific evaluation in women with CMV infection. Findings include microcephaly, ventriculomegaly, and cerebral calciications; ascites, hepatomegaly, splenomegaly, and hyperechoic bowel; hydrops; and oligohydramnios (Society for Maternal-Fetal Medicine, 2016). Abnormal sonographic findings seen in combination with positive findings in fetal blood or amnionic fluid are predictive of an approximate 75-percent risk of symptomatic congenital infection (Enders, 2001).
CMV nucleic acid amplification testing (NAA T) of amnionic luid is considered the gold standard for the diagnosis of fetal infection. Sensitivities range from 70 to 99 percent and depend on amniocentesis timing. Sensitivity is highest when amniocentesis is performed at least 6 weeks after maternal infection and after 21 weeks' gestation (Azam, 2001; Guerra, 2000). A negative result from amnionic luid polymerase chain reaction (PCR) testing does not exclude fetal infection and may need to be repeated if suspicion for fetal infection is high.
The management of the immunocompetent pregnant woman with primary or recurrent CMV is limited to symptomatic treatment. If recent primary CMV infection is conirmed, amnionic fluid analysis should be ofered. Counseling regarding fetal outcome depends on the gestational age during which primary infection is documented. Despite the high infection rate with primary infection in the first half of pregnancy, most fetuses develop normally. However, pregnancy termination may be an option for some.
Currently, no proven treatments are available for CMV infection (Society for Maternal-Fetal Medicine, 2016). Leruez-Ville and associates (2016) recently reported that oral treatment with valacyclovir, 8 g daily, apparently mitigated adverse outcomes in eight of 11 afected fetuses treated beginning at median of 25.9 weeks' gestation. Kimberlin and colleagues (2015) previously showed that intravenous valganciclovir administered for 6 weeks to neonates with symptomatic central nevous system (CNS) disease prevented hearing deterioration at 6 months and possibly later. Passive immunization with CMV-specific hyperimmune globulin may lower the risk of congenital CMV infection when given to pregnant women with primary disease (Nigro, 2005, 2012; Visentin, 2012). he Maternal-Fetal Medicine Units Network currently is conducting a randomized trial designed to address this.
here is no CMV vaccine, although several clinical trials are underway (Arvin, 2004; Schleiss, 2016). Prevention of congenital infection relies on avoiding maternal primary infection, especially in early pregnancy. Basic measures such as good hygiene and hand washing have been promoted, particularly for women with toddlers in day-care settings (Fowler, 2000).
CMV may be sexually transmitted among infected partners, but no data address the eicacy of preventive strategies.