Identification of anaerobic Gram negative rods

Public health England has issued “UK Standards for Microbiology Investigations ID 25: identification of anaerobic Gram negative rods.”

The taxonomy of the anaerobic bacteria is in a state of continuous change due to the constant addition of new species and the reclassification of the old1. An example of this would be the genus Bacteroides. This genus previously included most of the saccharolytic pigmented species that are now included in the genus Prevotella and the asaccharolytic species which have been assigned to the genus Porphyromonas.

There are more than 20 genera of anaerobic Gram negative rods. The most common human isolates belong to the genera Bacteroides, Fusobacterium, Porphyromonas and Prevotella. Other genera that have been associated with infections in humans are, Parabacteriodes, Odoribacter, Tannerella, Alloprevotella and Mitsuokella.

The document provides guidance about the identification of these organisms. To access the document, see Public Health England.

Posted by Tim Sandle