Legionella indianapolisensis sp. nov., isolated from a patient with pulmonary abscess

• Main Authors: R.F. Relich, B.H. Schmitt, H. Raposo, L. Barker, S.J. Blosser, M. May
• Format: Article
• Language: English
• Published: Elsevier 2018-04-01
• Series: International Journal of Infectious Diseases
• Online Access: http://www.sciencedirect.com/science/article/pii/S1201971218300250

Background: To date, at least 50 species of Legionella have been described. These organisms are ubiquitous in nature and have been isolated from diverse ecological environments, including man-made structures such as cooling towers and spas. Legionellae have also been isolated from human and veterinary clinical specimens, and their roles in disease are well-established. This report describes the isolation of a novel Legionella species from a respiratory specimen from a patient with influenza and suspected pulmonary embolus. Case: A 68-year-old male presented to an Indianapolis-area hospital with pulmonary disease; upon workup, he was found to have influenza A. Bronchoalveolar lavage fluid was also submitted for conventional bacterial culture and Legionella culture. The patient was prescribed a broad-spectrum antibiotic and recovered. Results: A Legionella-like bacterium was isolated on buffered charcoal yeast extract agar, and mass spectrometry and comparative 16S rRNA gene sequencing inconclusively identified the isolate as a Legionella sp. Further analysis of the 16S rRNA gene confirmed the strain to be a new species, related to Legionella hackeliae. Physiochemical and morphological testing were used to confirm the discovery of a novel species, Legionella indianapolisensis sp. nov., type strain SMNF-IS. Keywords: Legionella indianapolisensis, Legionella, Legionellae, Pulmonary abscess, Influenza, Co-infection, Lobar pneumonia