Chorioamnionitis due to Leptotrichia trevisanii

Very long fusiform gram-negative bacilli were observed after Gram staining of amniotic fluid from a 36-year-old multigravida woman. At 24 hours, pure, abundant growth of smooth, gray, only slightly convex catalase-positive and oxidase-negative colonies measuring about 2 mm were observed. Growth was greater in anaerobic than in aerobic conditions. The bacterium was identified as Leptotrichia trevisanii by matrix-assisted laser desorption ionization time of flight mass spectrometry. Ampicillin and gentamicin were prescribed for chorioamnionitis, and vaginal prostaglandins were administered to terminate the pregnancy. The patient remained afebrile throughout 48 hours and was discharged. Microscopic examination of the placenta revealed severe acute chorioamnionitis with a maternal inflammatory response and abundant bacillary-shaped microorganisms. To our knowledge, this isolate constitutes the first reported case of chorioamnionitis caused by L. trevisanii.