Sexually Transmitted Diseases - I. I. Mavrov 2005

Other bacterial infections of the urogenital organs
Infections caused by Bacteroides and other anaerobic microorganisms

The causative agents of this group of diseases are permanent normal "residents" of the Vagina and cervical canal. The most widespread species are Bacteroides fragilis, Bacteroides melaninogenicus, and Bacteroides oralis.

These are strictly anaerobic, typically gram-negative Bacteria characterized by marked polymorphism. They may appear as slender rods, branched structures, or rounded bodies. They grow best on complex media, such as Brain-Heart infusion Agar, under anaerobic conditions (in an atmosphere containing 10% CO₂). The Classification of bacteroides is based on The Study of colony Morphology and biochemical properties, as well as the results of gas Chromatography.

Bacteroides capsular Polysaccharides are an important virulence factor. During infections caused by Bacteroides fragilis, patients develop Antibodies against these capsular polysaccharides.

B. fragilis produce superoxide dismutase and can remain viable in the presence of oxygen for several days.

Bacteroides are part of the normal microbial flora not only of the FEMALE REPRODUCTIVE Organs, but also of the intestine, Upper Respiratory Tract, Oral Cavity, and Larynx. At the same time, pathogenic strains of these microorganisms very frequently cause Diseases of the Internal Female Genital organs: cervicitis, endometritis, adnexitis, and pelvic infections. Bacteroides are also detected in chronic, complicated urethritis in men (in 6.1% of patients with complicated post-gonococcal urethritis), as well as in patients with a protracted course of the disease and frequent relapses.

These microorganisms induce intravascular Blood Coagulation, which leads to severe phlebitis. Endocarditis, ulcerative lesions of the Skin and genital mucous membranes, Peritonitis, and bacteremia are also frequently observed.

In pelvic anaerobic infections, bacteroides are found in association with other anaerobic microorganisms, particularly anaerobic streptococci (Peptostreptococcus) and fusiform bacteria (Fusobacterium sp.), as well as gram-negative aerobic enteric bacteria.

Bacteroides are sensitive to Penicillins, especially broad-spectrum ones, and Cephalosporins. Meanwhile, B. fragilis exhibit relative resistance to penicillin, but are sensitive to clindamycin, ciprofloxacin, and metronidazole.