[Lymphocytic choriomeningitis virus and fetal anomalies]

Lymphocytic choriomeningitis virus (LCMV), a rodent-borne arenavirus, is an uncommonly recognized cause of severe congenital viral infection. The incidence of this infection during pregnancy is still unknown. Our study aimed to evaluate LCMV infection frequency in pregnancy with fetal neurological abnormalities of unknown etiology.

Samples obtained during three years from 160 pregnant women were retrospectively analysed: 155 maternal sera, 150 amniotic fluids (AF) and 12 fetal sera (FS). Congenital neurological anomalies were diagnosed but TORCH and culture investigations were negatives. Serological analysis was performed with L929 cells infected with the Armstrong strain of LCMV. IgG and IgM antibodies against CMLV were researched by immunofluorescence assay using these infected cells. Interferon alpha was also assayed for AF and FS.

No positive serology was found in any of the 317 samples investigated even when interferon alpha was detected.

This result confirms the rarity of LCMV infection in France. Nevertheless, at the light of the recent literature, this teratogenic pathogen should be considered in pregnancy with unexplained congenital malformation, especially after rodent exposure.