i. Bacteria: gram negative
i. Obligate anaerobe (can tolerate some air)
ii. Variable motility dependent on the strain
iii. Non-spore forming
iv. Most common of the genus is Bacteroides fragilis.
i. Normal component of the GI flora
ii. Also found in the vagina in 60% of women
iii. If given route into abdominal cavity (ex. Trauma, ulcer, surgery), it can cause intra-abdominal infection.
iv. Not communicable
d. Laboratory diagnosis
i. Blood agar plates containing kanamycin and vancomycin
ii. Identified by biochemical reactions and production of organic acids detected by gas chromatography
iii. grows under anaerobic conditions
e. Disease manifestations
i. Most common cause of serious anaerobic infections
ii. Causes peritonitis – inflammation of the peritoneum lining inner walls of the abdomen and covers most abdominal organs.
iii. Most frequently associated with intra-abdominal infections – peritonitis or localized abscess.
iv. May also see pelvic abscess, necrotizing fasciitis, and bacteremia
i. Usual treatment is with metronidazole, carbapenems, tigecycline, or beta-lactam/beta-lactamase inhibitor.
ii. Resistant to penicillins (because have beta-lactamase), macrolides, tetracyclines, and aminoglycosides
iii. Among the most-resistant of anerobic bacteria.
iv. Surgical drainage of abscess along with antibiotic therapy
i. Perioperative administration of cephalosporin (often cefoxitin) before abdominal or pelvic surgery.
ii. No vaccine available.