Rat Anti-P. intermedia Monoclonal antibody for WB, IF. Prevotella intermedia (formerly Bacteroides intermedius) is a gram-negative obligate anaerobic pathogen involved in periodontal infections, including gingivitis and periodontitis, and often found in Acute necrotizing ulcerative gingivitis. It is commonly isolated from Dentoalveolar abscesses, where obligate anaerobes predominate. It is thought that P. intermedia is more prevalent in patients with noma known also as Cancrum oris. Prevotella intermedia use steroids as growth factors. For that reason P. intermedia"s number is higher in pregnant women.