Primary, secondary maternal infections contribute to congenital cytomegalovirus

Both primary and secondary cytomegalovirus (CMV) infections in mothers contribute to the risk of symptomatic congenital CMV (cCMV) and its long-term sequelae, according to a recent study.

“Our study aims to emphasize that cCMV infections due to secondary maternal infections can be as serious as those due to primary infections, both at birth and during follow up; the less attention often given to seropositive mothers can lead to missed diagnosis of congenital infections in children who may develop serious sequelae,” the researchers said.

The monocentric retrospective analysis included 53 infants with available maternal infection information and who had symptomatic cCMV. Of the neonates, 40 were born to mothers with primary infections and 13 to those with secondary infections. CCMV at birth was diagnosed based on the presence of CMV DNA in urine or blood samples or on a Guthrie card.

Symptomatic infection at birth was detected at comparable rates between infants born to mothers with primary vs secondary CMV (33.9 percent vs 48.1 percent; p=0.165). [Front Pediatr 2022;doi:10.3389/fped.2022.885926]

Symptoms were likewise comparable between groups at birth. For example, small for gestational age was detected in 2.5 percent vs 7.7 percent of infants born to mothers with primary vs secondary infections (p=0.434), while corresponding rates for microcephaly were 5 percent vs 15.4 percent (p=0.249).

Other manifestations of infection, such as abnormal magnetic resonance imaging (66.7 percent vs 50 percent), hepatomegaly (10 percent vs 0 percent; p=0.561), splenomegaly (7.5 percent vs 0 percent; p=0.567), neurological symptoms (27.5 percent vs 46.2 percent; p=0.211), and anaemia (2.5 percent vs 0 percent; p=1) were also similar between those in the primary vs secondary maternal infection groups.

The only exception was unilateral sensorineural hearing loss (SNHL), which occurred at a significantly higher frequency in infants born to mothers with primary CMV infections (46.2 percent vs 17.5 percent; p=0.037).

The incidences of long-term sequelae were also generally comparable between groups. Epilepsy, for instance, arose in 2.5 percent and 7.7 percent of infants born to moms with primary vs secondary infections (p=0.434). The same was true for motor (22.5 percent vs 38.5 percent; p=0.257), speech (30 percent vs 53.8 percent; p=0.119), and cognitive (0 percent vs 0 percent; p=1) delays, as well as any neurodevelopmental impairment (45 percent vs 53.8 percent; p=0.579).

In contrast, unilateral SNHL remained significantly elevated in those born to mothers with secondary infections (46.2 percent vs 12.5 percent; p=0.009), an effect that was also observed for tetraparesis (30.8 percent vs 0 percent; p=0.002).

“[I]ncreasing hygienic measures in those women may reduce the number of reinfection and, consequently, the number of cCMV. Moreover, paying more attention to seropositive women could allow to detect and possibly treat otherwise unrecognized infected babies,” the researchers said.