Genetica

Primary versus Nonprimary Cytomegalovirus Infection during Pregnancy, Israel
Galia Rahav,*1 Rinat Gabbay,* Asher Ornoy,*† Svetlana Shechtman,† Judith Arnon,† and Orna Diav-Citrin†
We examinedprospectively the outcome of primary and nonprimary maternal cytomegalovirus (CMV) infection during pregnancy among 88 and 120 women, respectively. The risk for vertical transmission was 1.83× higher forprimary infection than for nonprimary infection. Nonetheless, congenital CMV disease was diagnosed in both infection groups at similar rates.

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ytomegalovirus (CMV) infection is the most frequentcongenital infection and a common cause of deafness and intellectual impairment, affecting 0.5%–2.5% of all live births (1–3). Intrauterine infection occurs in 40% of primary maternal infections,with delivery of 10% to 15% symptomatic newborns and late neurologic sequelae in 10% of those asymptomatic at birth (1). Although preexisting maternal immunity reduces maternal-fetal transmission, theseverity of congenital CMV disease is similar following primary or nonprimary infection (4–7). Yet, several reports found increased vertical transmission after nonprimary CMV infection (4–9). Therefore,our objective was to examine the outcome of primary and nonprimary maternal CMV infections during pregnancy. The Study Institutional Ethics Committee approval was obtained. Women with positive CMVimmunoglobulin (Ig) M (n = 208), referred for risk for CMV infection between January 1998 and December 2001, were enrolled in this prospective cohort observational study. Clinical and pregnancy-relatedinformation was obtained. Serum CMV IgG and IgM were measured by enzyme immunoassay and CMV-IgM immunofluorescence assay (10). IgG avidities 35% were considered to have nonprimary infection (12). Thelatter were divided into those with preconception evidence of anti–CMV IgG and negative anti–CMV IgM (group 1) and those without prior tests for CMV (group 2). Vertical transmission was declared if...