MICROBIOLOGY

• Non-motile Gram-negative bacillus; may appear as slender rods or coccobacilli. [Fig 1and Fig 2]
  • Usually recovered in anaerobic cultures.
  • Previously described as a Bacteroides species, reclassified under the genus Prevotella.[14]
  • Slow grower, some species require > 48 hrs incubation.
  • As for all anaerobic bacteria, diagnosis of Prevotella spp. infections require specialized techniques for transport, isolation, processing and identification.
    • Prevotella identification in many laboratories is still based on phenotypic methods.
    • Prevotella spp. are bile-sensitive and vancomycin-resistant in contrast to species of the Bacteroides fragilis group and Porphyromonas spp., respectively.[7]
• More than 50 species of Prevotella have been identified.
  • In oral and head-and-neck infections, common isolates were Prevotella intermedia and Prevotella melaninogenica within the pigmented species as well as Prevotella oris and Prevotella oralis group within the non-pigmented species.[6]
• Prevotella species are intrinsically resistant to aminoglycosides, aztreonam, trimethoprim, sulfonamides and fosfomycin.[7]