[Neonatal meningitis due to Listeria monocytogenes after 3 weeks of maternal treatment during pregnancy].

We report the case of a pregnant woman with listeriosis at 26 gestational weeks followed by premature labor at 30 gestational weeks. Bacterial meningitis was suspected in the neonate with ventriculitis on sonography, a high level of protein in the cerebrospinal fluid (CSF), and an identified specific bacterial genome of Listeria monocytogenes (PCR 16S rDNA and sequencing and specific amplification of L. monocytogenes hly gene) in CSF. Neonatal meningitis was complicated with cerebral venous sinus thrombosis and ventriculomegaly. Listeriosis during pregnancy can lead to severe complications in the neonate. Thus, listeriosis should be a diagnostic concern in febrile pregnant women at any stage of pregnancy. First-line treatment is based on high-dose amoxicillin (> or =6g/day) and must be used for at least 3 weeks for treatment of listeriosis during pregnancy. If the fetus survives, longer therapy until delivery can be discussed.