Listeriosis during pregnancy usually presents as an unremarkable febrile illness in the mother but can be fatal for the fetus and newborn. Reliable laboratory testing for early diagnosis is lacking. Serological antibody tests and bacteriological stool tests are not helpful since Listeria-specific antibodies and stool cultures yielding the organism can be found in healthy pregnant women. Because early diagnosis is difficult, diagnosis is usually made by culturing the pathogen from blood, cerebrospinal fluid, placenta or meconium. The mortality rate for fetal and newborn listeriosis remains approximately 20%. Two to three cases of pregnancy-associated listeriosis are reported annually in Austria among approximately 79,000 births, 20-30 cases are reported annually in Germany among approximately 680,000 births and 50-100 cases are reported annually in the USA among approximately 4 million births. Although Listeria infections in pregnancy are rare, they should be considered as a cause of fever of unknown origin during pregnancy.
Keywords: Listeria monocytogenes; diagnosis; pregnancy; prevention; treatment.