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A rare congenital nongenetic disorder resulting from
maternal transmission of varicella in the first and second trimesters of
pregnancy manifesting with cutaneous, neurologic, and limb involvement.
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Fetal Varicella Syndrome; Varicella Virus Antenatal
Infection; Varicella Embryopathy; Varicella Fetopathy.
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Because most women of child-bearing age (>90%) have
antibodies (IgG) against the varicella-zoster virus, infection during
pregnancy is rare. Approximately 2% of babies suffer from the syndrome
following maternal varicella infection in the first 20 weeks of pregnancy
(greatest risk between weeks 8 to 20). In industrialized countries,
approximately 0.5-3:1000 pregnancies are affected. However, a significantly
higher rate is expected in developing countries. Approximately 100 cases
have been described in the medical literature. Two thirds of affected
neonates are females.
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The route of infection most likely is
transplacental and leads to fetal viremia, although ascending infection from
the cervix uteri is possible. Organ injuries reflect the neurotropic nature
of the varicella virus.
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Based on the history of maternal chickenpox in the first
or second trimester of pregnancy and clinical and serologic (IgM-specific
antibodies, persistence of IgG antibodies beyond the first 6 months of life)
findings in the neonate with low birth weight and multiple, characteristic
abnormalities (see Clinical Aspects).
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At any stage of pregnancy, severe maternal
chickenpox may result in fetal death. The features of the disorder may
involve the skin (cicatricial lesions associated with underlying tissue
hypoplasia; the lesions appear depressed and hyperpigmented and often have
an irregular border; certain skin areas [mainly arms and legs in dermatomal
distribution] may exhibit thickened and hypertrophic scars with induration,
redness, and inflammation of the surrounding skin), the eyes
(microphthalmia, microcornea, anisocoria, chorioretinitis, optic nerve
atrophy and hypoplastic optic disc, cataract, corneal opacities,
enophthalmia, strabismus, and nystagmus), the central nervous system
(cortical and spinal cord atrophy, cerebellar aplasia, seizures,
encephalitis, deafness, generalized hypotonia, hyperreflexia, intermittent
myoclonic seizures, Horner syndrome, developmental delay, limb paresis), the
musculoskeletal system (signs of hypoplasia and/or reduction deformities of
the limbs including fingers and toes, hypoplastic mandible, clavicle,
scapula, ribs, muscles), the gastrointestinal tract (hepatic calcifications,
gastroesophageal reflux, duodenal stenosis, jejunal dilatation, chronic
constipation, microcolon, colonic atresia, anal sphincter dysfunction), the
urogenital tract (vesicoureteral reflux, neurogenic bladder), and the
cardiovascular system. Intrauterine growth retardation is common. Almost one
third of these patients die in the first months of life.
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The patient is infectious, so avoid
contact with medical personnel who is at risk for contracting varicella or
whose immune status is unknown. Isolation from other patients is required
because varicella is highly contagious. Evaluate the patient for less common
manifestations, such as cardiovascular abnormalities (in 8% of patients)
and maintain a low threshold for echocardiography. Obtain a full medical
history and evaluate neurologic development, seizure control, and extent of
paresis. Laboratory investigations should include a complete blood count,
serum concentrations of electrolytes, creatinine, and urea (because
vesicoureteral reflux may affect kidney ...