Rhombencephalitis in Pregnancy—A Challenging Case of Probable Listeria Infection

Rhombencephalitis refers to inflammation of the brainstem and cerebellum, and can be caused by infections, autoimmune disorders or paraneoplastic syndromes. The most common infective cause is the bacterium Listeria monocytogenes. Listeria monocytogenes is the predominant species to cause human listeriosis, and is commonly due to the ingestion of contaminated foods. Symptoms include a mild gastroenteritis, fever (often with extreme temperature variations), headache, and myalgia. In more severe cases, invasive disease may lead to bacteraemia and neurolisteriosis. Pregnant women are more susceptible to listeriosis, which is believed to be due to pregnancy-related immune modulation. Maternal-neonatal infection with adverse pregnancy outcomes include neonatal listeriosis, spontaneous miscarriage and intrauterine fetal demise. Diagnosis may be challenging due to initial nonspecific symptoms and low sensitivity and specificity of confirmatory diagnostic laboratory tests. Here, we describe a case of rhombencephalitis in pregnancy, attributed to Listeria, and review the clinical features, diagnosis and multidisciplinary management. Lastly, we describe the immunological response to Listeria monocytogenes and show in vitro pro-inflammatory effects of Listeria monocytogenes on peripheral blood mononuclear cells and placental explants.