Antisera against seven strains of Bacteroides fragilis subspecies fragilis were produced from dense suspensions of whole cells. These sera exhibited high agglutination titers with homologous antigens. Reciprocal cross-reactions in agglutination tests with each immunizing strain yielded lower titers. Both the indirect and direct fluorescent-antibody techniques were used to evaluate these reagent...

Recently, Dientamoeba fragilis has emerged as a significant and common enteropathogen. The majority of patients with dientamoebiasis present with gastrointestinal complaints and chronic symptoms are common. Numerous studies have successfully demonstrated parasite clearance, coupled with complete resolution of clinical symptoms following treatment with various antiparasitic compounds. Despite th...

Bacteroides fragilis is an anaerobic bacterial species that is involved in gynecological infections and pathology. The incidence of vaginal carriage is largely unknown, and in order to study this, 120 pregnant women attending a general hospital for delivery were examined. Cultures were positive for eight of these women (6.6%). Interestingly, potential clonal relatedness could be demonstrated am...

The Bacteroides fragilis group is one of the most important pathogens in polymicrobial infections. The distribution of the different members of the B. fragilis group in clinical infections varies. Bacteroides fragilis accounts for 63 percent of all the group isolates, Bacteroides thetaiotaomicron for 14 percent, Bacteroides vulgatus and Bacteroides ovatus for seven percent each, Bacteroides dis...

Among 750 symptomatic and asymptomatic patients, Dientamoeba fragilis was detected at a prevalence of 5.2% and more common than Giardia intestinalis. Most infected patients presented with diarrhea and abdominal pain with symptoms greater than 2 weeks duration being common. Bacterial and viral causes of infection were excluded by routine microbiological techniques. Treatment of D. fragilis infec...

A retrospective analysis of susceptibility data on 542 blood isolates of the Bacteroides fragilis group tested from 1987 to 1999 by the same NCCLS-recommended broth microdilution method throughout is presented. Metronidazole, beta-lactam-beta-lactamase inhibitor combinations, carbapenems, and trovafloxacin were the most active agents (susceptibility of >or=93%). Among the cephalosporin-cephamyc...

Bacteroides fragilis is the most common anaerobe isolated from clinical infections, and in this report we demonstrate a characteristic of the species that is critical to their success as an opportunistic pathogen. Among the Bacteroides spp. in the gut, B. fragilis has the unique ability of efficiently harvesting complex N-linked glycans from the glycoproteins common to serum and serous fluid. T...

The importance of gut commensal bacteria in maintaining immune homeostasis is increasingly understood. We recently described that alteration of the gut microflora can affect a population of Foxp3(+)T(reg) cells that regulate demyelination in experimental autoimmune encephalomyelitis (EAE), the experimental model of human multiple sclerosis. We now extend our previous observations on the role of...

The antibiotic susceptibility rates of 363 clinical Bacteroides fragilis group isolates collected from 17 centers in Argentina during the period from 2006 to 2009 were as follows: piperacillin-tazobactam, 99%; ampicillin-sulbactam, 92%; cefoxitin, 72%; tigecycline, 100%; moxifloxacin, 91%; and clindamycin, 52%. No metronidazole resistance was detected in these isolates during this time period. ...

Bacteroides fragilis HSP40 phages have been detected in waters with various levels of fecal contamination of human origin. The average numbers of B. fragilis phages present in sewage water reached 5.3 x 10(3) per 100 ml of water. We found a number 1,000 times lower in a river contaminated with domestic sewage only, in which the levels of fecal coliforms and fecal streptococci were 10,000 times ...