Exxcellence pearls: CMV

Question 0

What is the incidence of CMV congenital infections?

What percentage of women have primary CMV infection during pregnancy?

Answer 0

0.5%

4%

Question 1

What is the rate of vertical transmission with primary maternal infection?

When during pregnancy does the risk of vertical transmission increase?

When during pregnancy is congenital CMV the most severe?

Answer 1

33%

Increases with gestational age

First trimester

Question 2

How does CMV present?

Answer 2

Mononucleosis-like illness with fever and mild hepatitis. 90% of women are asymptomatic

Question 3

What percentage of surviving infants with CMV infection develop long-term sequelae?

What are these findings?

Answer 3

60%

Neurodevelopmental abnormalities such as cognitive impairment and hearing or vision loss

Question 4

What percentage of infected fetuses are born with CMV sequelae?

What are neonatal findings?

What is the mortality rate?

Answer 4

20%

SGA, microcephaly, ventriculomegaly, hepatosplenomegaly, hepatitis, chorioretinitis, thrombocytopenia

5%

Question 5

What is the rate of vertical infection with a secondary CMV infection?

How do infected offspring typically present?

Answer 5

2%

Most newborns are asymptomatic but still at risk of developing neurodevelopmental abnormalities

Question 6

How is CMV infection diagnosed?

How can primary versus secondary infection be determined?

Answer 6

Presence of CMV IgG antibodies in a woman who was previously seronegative

Since both CMV IgG and IgM will be present after a primary or secondary infection, avidity testing will be helpful. Low avidity suggests recent primary infection

Question 7

When is CMV testing indicated?

Is routine screening recommended?

Answer 7

Women with mononucleosis like illness or concern fetal CMV infection based on sonographic findings such as periventricular hyperechogenicity

No. 50% of reproductive age women have evidence of prior CMV infection

Question 9

How is CMV infection confirmed? When is this done?

Answer 9

PCR testing for CMV DNA by amniocentesis should be performed after 21 weeks and at least six weeks after maternal infection.

Question 10

How should a fetus with CMV infection be monitored?

How is fetal CMV treated?

Answer 10

Serial ultrasound to measure growth and development of features of fetal CMV including CNS abnormalities, echogenic bowel or liver, and hydrops. Amniotic fluid viral load can be used to aid in estimation of fetal prognosis

Supportive care. There is no effective treatment for prevention production of sequelae.