ultrasound diagnosis of fatal anomalies

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INFECTIONS
Congenital Varicella
Definition: Infection with varicella zoster virus.
This is a DNA virus belonging to the family of
herpesviruses. The primary infection causes
chickenpox; reactivation of the virus at a later
stage from the sensory roots of the posterior
horn of the spinal cord is responsible for the
clinical symptoms of herpes zoster.
Incidence: Maternal infection during pregnancy,
one in 2000–10 000. The risk of congenital infection
to the fetus is low; congenital malformations
result in less than 5% of cases.
Origin: The virus affects the nervous system,
causing neurological impairment of fetal structures.
Infections in the first trimester cause the
most severe damage.
Clinical features: Focal ulceration of the skin and
anomalies described in the following section.
Ultrasound findings: Rarely, the following are
detected: growth restriction, hydramnios, microphthalmia,
hydrocephalus, or microcephaly;
ascites, pleural effusions and even full-fledged
fetal hydrops; hepatic calcification, club feet and
other limb anomalies, reduction in fetal movements.
These anomalies develop only in the
most severely affected cases, about 3–12 weeks
after maternal infection.
Clinical management: Serology of maternal
blood; fetal IgM is detectable from 20 weeks,
amniotic fluid culture, chorionic villus sampling
and polymerase chain reaction, regular scanning
controls (is hydrocephalus developing?). IgG
may be given to the mother within 72–96 h if the
mother has been in contact with an infected individual
and is not immune.
Procedure after birth: Acyclovir may be given
after birth.
Prognosis: The infants usually do not show any
symptoms. Fetal anomalies appear in 1–2% of
cases if infection occurs before 20 weeks of gestation.
About one-third of the most severely affected
infants die in the early neonatal stage; in
the surviving infants, mental impairment and
fits may occur.
References
Dufour P, de Bièvre P, Vinatier D, et al. Varicella and
pregnancy. Eur J Obstet Gynecol Reprod Biol 1996;
66: 119–23.
Harger JH, Ernest JM, Thurnau GR, et al. Frequency of
congenital varicella syndrome in a prospective cohort
of 347 pregnant women. Obstet Gynecol 2002;
100: 260–5.
Kerkering KW. Abnormal cry and intracranial calcifications:
clues to the diagnosis of fetal varicella-zoster
syndrome [review]. J Perinatol 2001; 21: 131–5.
Lecuru F, Taurelle R, Bernard JP, et al. Varicella zoster
virus infection during pregnancy: the limits of prenatal
diagnosis. Eur J Obstet Gynecol Reprod Biol
1994; 56: 67–8.
Mets MB. Eye manifestations of intrauterine infections
[review]. Ophthalmol Clin North Am 2001; 14: 521–
31.
Petignat P, Vial Y, Laurini R, Hohlfeld P. Fetal varicellaherpes
zoster syndrome in early pregnancy: ultrasonographic
and morphological correlation. Prenat
Diagn 2001; 21: 121–4.
Pons JC, Vial P, Rozenberg F, et al. Prenatal diagnosis of
fetal varicella in the second trimester of pregnancy. J
Gynecol Obstet Biol Reprod (Paris) 1995; 24: 829–38.
Taylor WG, Walkinshaw SA, Thomson MA. Antenatal
assessment of neurological impairment. Arch Dis
Child 1993; 68: 604–5.
Yaron Y, Hassan S, Geva E, Kupferminc MJ, Yavetz H,
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