Perinatal listeriosis underdiagnosed as a cause of pre-term labour?

Between April 1, 1985, and April 1, 1986, four cases of perinatal listeriosis were reported at the Maastricht Academic Hospital. All cases were of the early-onset type. All mothers were admitted for pre-term labour between 28 and 33 weeks of gestation. Pre-natal symptoms included maternal fever, non-characteristic influenza-like manifestations, leucocytosis and (pre-term) meconium-stained amniotic fluid. Two neonates died, one in utero and one due to listeriosis sepsis. Another neonate developed a hydrocephalus. Only one neonate has survived without damage up to now. Such a high incidence of listeriosis and the high perinatal morbidity and mortality rates are remarkable. Epidemiological, bacteriological and placental sequelae of Listeria monocytogenes are discussed.