Distribution, detection of enterotoxigenic strains and antimicrobial drug susceptibility patterns of Bacteroides fragilis group in diarrheic and non-diarrheic feces from Brazilian infants

Abstract

Despite the importance of gastrointestinal diseases and their global distribution, affecting millions of individuals around the world, the role and antimicrobial susceptibility patterns of anaerobic bacteria such as those in the Bacteroides fragilis group (BFG) are still unclear in young children. This study investigated the occurrence and distribution of species in the BFG and enterotoxigenic strains in the fecal microbiota of children and their antimicrobial susceptibility patterns. Diarrheic (n=110) and non-diarrheic (n=65) fecal samples from children aged 0-5 years old were evaluated. BFG strains were isolated and identified by conventional biochemical, physiological and molecular approaches. Alternatively, bacteria and enterotoxigenic strains were detected directly from feces by molecular biology. Antimicrobial drug susceptibility patterns were determined by the agar dilution method according to the guidelines for isolated bacteria. BFG was detected in 64.3% of the fecal samples (55% diarrheic and 80.4% non-diarrheic), and 4.6% were enterotoxigenic. Antimicrobial resistance was observed against ampicillin, ampicillin/sulbactam, piperacillin/tazobactam, meropenem, ceftriaxone, clindamycin and chloramphenicol.The data show that these bacteria are prevalent in fecal microbiota at higher levels in healthy children. The molecular methodology was more effective in identifying the B. fragilis group when compared to the biochemical and physiological techniques. The observation of high resistance levels stimulates thoughts about the indiscriminate use of antimicrobial drugs in early infancy. Further quantitative studies are needed to gain a better understanding of the role of these bacteria in acute diarrhea in children.

Alterations of Intestinal Microbiome by Antibiotic Therapy in Hospitalized Children

“…29 Several studies have reported similar prevalence of B. fragilis, B. vulgatus, and P. distasonis in human fecal microbiota. 30,31 In this study, B. vulgatus was found in high prevalence in the nontreated children than the treated ones (70% vs. 19.3%, respectively), whereas P. distasonis was observed more in the antibiotic-treated children (in 20% control children vs. 38.7% antibiotic-treated). This suggested that the species B. fragilis and B. vulgatus are sensitive and P. distasonis is resistant toward antibiotic therapy.…”

Prevalence and antibiotic susceptibility of Bacteroides fragilis group isolated from stool samples in North Lebanon

“…A very good activity of meropenem has been reported by Oteo et al (2000) With 100% of susceptibility, but a higher rate of resistance was reported by Ferreira et al (2010) (18.2%).…”

“…In a study performed by Ferreira et al (2010) in Brazil, the authors reported entirely different results, where P. distasonis was the major species (19.1%), followed by B. fragilis (17.0%), B. vulgatus (17.0%), B. caccae (2.1%) and P. merdae (2.1%).…”

“…Oteo et al (2000) Ferreira et al (2010) and Nakano and Avila-Campos (2004) reported high values of resistance (49%, 22.7% and 23.5%, respectively) in studies performed in Spain and Brazil.…”

Polymerase chain reaction for the evaluation of Schistosoma mansoni infection in two low endemicity areas of Minas Gerais, Brazil

“…To this end, 20% of the DNA samples obtained from different cities were used. Primers were designed to amplify a 1,067 bp sequence of the 16S rDNA gene of bacteria (Ferreira et al 2010). For amplification, 5 μL of the extracted material was used.…”