Bacteroides faecis and Bacteroides intestinalis Recovered from Clinical Specimens of Human Intestinal Origin

We report three cases of recently named Bacteroides spp. isolates, two B. faecis isolates and one B. intestinalis isolate from clinical specimens of inpatients at a Korean tertiary-care hospital in 2011. All isolates were susceptible to piperacillin-tazobactam, imipenem, meropenem, chloramphenicol, and metronidazole.

Antimicrobial resistance and prevalence of resistance genes in intestinal Bacteroidales strains

OBJECTIVE: This study examined the antimicrobial resistance profile and the prevalence of resistance genes in Bacteroides spp. and Parabacteroides distasonis strains isolated from children's intestinal microbiota. METHODS: The susceptibility of these bacteria to 10 antimicrobials was determined using an agar dilution method. β-lactamase activity was assessed by hydrolysis of the chromogenic cephalosporin of 114 Bacteriodales strains isolated from the fecal samples of 39 children, and the presence of resistance genes was tested using a PCR assay. RESULTS: All strains were susceptible to imipenem and metronidazole. The following resistance rates were observed: amoxicillin (93 percent), amoxicillin/clavulanic acid (47.3 percent), ampicillin (96.4 percent), cephalexin (99 percent), cefoxitin (23 percent), penicillin (99 percent), clindamycin (34.2 percent) and tetracycline (53.5 percent). P-lactamase production was verified in 92 percent of the evaluated strains. The presence of the cfiA, cepA, ermF, tetQ and nim genes was observed in 62.3 percent, 76.3 percent, 27 percent, 79.8 percent and 7.8 percent of the strains, respectively. CONCLUSIONS: Our results indicate an increase in the resistance to several antibiotics in intestinal Bacteroides spp. and Parabacteroides distasonis and demonstrate that these microorganisms harbor antimicrobial resistance genes that may be transferred to other susceptible intestinal strains.

The use of ozonated water and 0.2% chlorhexidine in the treatment of periodontitis patients: A clinical and microbiologic study.

Background: The development of periodontal disease has been thought to be associated with several restricted members of the oral anaerobic species, such as black-pigmented Porphyromonas species and Actinobacillus actinomycetemcomitans (Aa), in the subgingival environment. Apart from bacteria, certain viruses and fungi that are associated with periodontal disease are also present in the subgingival plaque . Materials and Methods: A randomized, double-blind, crossover split-mouth design was performed. A total of 16 patients suffering from generalized chronic periodontitis were selected for the study. The study period of 18 days was divided into two time-intervals, i.e. baseline (0 days) to 7 th day, with a washout period of 4 days followed by a second time interval of 7 days. The use of ozone and chlorhexidine gluconate (CHX) irrigation was randomized. Both the patient and the clinician evaluating the clinical parameters were blinded regarding the type of irrigation used. Results: The interpretation of clinical and microbial data is from baseline to 7 th day. A higher percentage of plaque index (12%), gingival index (29%) and bleeding index (26%) reduction was observed using ozone irrigation as compared to chlorhexidine. The percentile reduction of Aa (25%) using ozone was appreciable as compared to no change in Aa occurrence using chlorhexidine. By using O 3 and chlorhexidine, there was no antibacterial effect on Porphyromonas gingivalis (Pg) and Tannerella forsythensis. The antifungal effect of ozone from baseline (37%) to 7 th day (12.5%) was pronounced during the study period, unlike CHX, which did not demonstrate any antifungal effect. Conclusion: Ozone may be considered as an alternative management strategy due to its powerful ability to inactivate microorganisms. Also, there is growing evidence that ozone can be employed as a useful therapeutic agent in both dentistry and medicine.

Influence of local tetracycline on the microbiota of alveolar osteitis in rats

The aim of the present study was to evaluate the effects of local tetracycline on the occurrence of alveolar osteitis in rats, and on the microbiota associated to this infection. Forty Wistar rats were randomly assigned to 4 groups (n=10): I - the rats had the maxillary right incisor extracted and the alveolar wound did not receive any treatment; II - adrenaline and Ringer-PRAS were introduced into the alveolar wound; III - the alveolar wound was irrigated with sterile saline; and IV - the alveolar wound was irrigated with an aqueous solution of tetracycline. Microbial samples from the alveolar wounds were collected 2 days after surgery and inoculated on blood agar (with and without 8 µg/mL of tetracycline) and other selective media, and were incubated in either aerobiosis or anaerobiosis at 37ºC, for 2 to 14 days. It was verified that tetracycline reduced the occurrence of alveolar osteitis in the rats and caused significant changes in the microbiota of the surgical sites, decreasing the number of anaerobes and increasing the participation of tetracycline-resistant and multi-resistant microorganisms.

O objetivo do presente estudo foi avaliar os efeitos do uso tópico de tetraciclina sobre a ocorrência de alveolite em ratos e sobre a microbiota a ela associada. Quarenta ratos foram divididos, ao acaso, em 4 grupos (n=10): grupo I, realizou-se somente a extração do incisivo superior direito e a ferida alveolar não recebeu nenhum tratamento; grupo II, além da extração dental, soluções de adrenalina e Ringer-PRAS foram introduzidas no interior do alvéolo; grupo III, a ferida alveolar foi irrigada com solução salina estéril; grupo IV, a ferida alveolar foi irrigada com solução aquosa de cloridrato de tetraciclina a 10 por cento. As amostras dos alvéolos para processamento microbiológico foram coletadas dois dias após a realização das cirurgias e foram inoculadas em ágar sangue com ou sem 8 µg/mL de tetraciclina e em outros meios de cultura seletivos, incubadas em aerobiose ou anaerobiose, a 37ºC, de 2 a 14 dias. Verificou-se que a tetraciclina reduziu a ocorrência de alveolite e provocou uma modificação significativa na microbiota do sítio cirúrgico, levando a uma redução nas proporções ocupadas pelos microrganismos anaeróbios e uma elevação da participação de microrganismos resistentes à tetraciclina e outros antimicrobianos.

Microbiota intestinal de indivíduos que sofreram acidente ocupacional com materiais biológicos e que realizaram profilaxia anti-retroviral / Intestinal microbiota of individuals who suffered occupational accidents with biological materials and underwent antiretroviral prophylaxis

Avaliar a microbiota intestinal de indivíduos que sofreram acidente ocupacional com materiais biológicos e receberam anti-retrovirais foi o objetivo deste estudo. O grupo de estudo constou de 23 indivíduos com idade entre 18-45 anos, sendo 13 doadores de sangue e 10 que sofreram acidente ocupacional. Foram avaliados a microbiota intestinal, antropometria e exames laboratoriais pré, pós e 30 dias após o término da medicação. Zidovudina mais lamivudina foi utilizada em 70 por cento dos indivíduos associado ao nelfinavir, 20 por cento ao efavirenz e 10 por cento ao ritonavir. As alterações nutricionais e dietéticas-laboratoriais e de microbiota intestinal foram analisadas em três momentos. M1: até dois dias do início da profilaxia; M2: no último dia da profilaxia e M3: 30 dias após o término da profilaxia. Náuseas, vômitos e diarréia estiveram presentes em 50 por cento no segundo momento do estudo. Sobrepeso em 70 por cento, desnutrição e eutrofia em 10 por cento, dos indivíduos, não se modificaram durante o estudo. Transaminases, triglicérides, LDL-colesterol se elevaram no segundo momento e normalizaram 30 dias após término da medicação. Houve redução significativa dos Lactobacillus, Bifidobacterium e Bacteróides nos três momentos. Uso de anti-retrovirais provocou impacto significativo na microbiota intestinal dos indivíduos, sem recuperação em 30 dias.

The aim of this study was to evaluate the intestinal microbiota of individuals who had suffered occupational accidents and had received antiretrovirals. The study group consisted of 23 individuals between 18 and 45 years old, of whom 13 were blood donors and 10 had suffered occupational accidents. Intestinal microflora, anthropometry and laboratory tests were evaluated before, after and 30 days after discontinuation of the medication. Zidovudine plus lamivudine was used in association with nelfinavir for 70 percent of the individuals, with efavirenz for 20 percent and with ritonavir for 10 percent. Nutritional, diet, laboratory and intestinal microbiota abnormalities were analyzed at three times: M1, not more than two days after starting prophylaxis; M2, on the last day of prophylaxis; and M3, 30 days after ending prophylaxis. Nausea, vomiting and diarrhea were present in 50 percent at M2. Overweight in 70 percent, malnutrition and eutrophy in 10 percent of the individuals remained unchanged during the study. Transaminases, triglycerides and LDL-cholesterol because elevated at M2 and normalized 30 days after discontinuation of the medication. There were significant reductions in Lactobacillus, Bifidobacterium and Bacteroides at the three times. The use of antiretrovirals caused a significant impact on the individuals’ intestinal microbiota, without recovery after 30 days.

Intestinal microbiota of patients with bacterial infection of the respiratory tract treated with amoxicillin

The intestinal tract harbors a huge diversity of metabolically-active aerobic and anaerobic bacteria that interact, forming a complex ecosystem. This microbiota has an important role in human metabolism, nutrition, immunity, and protection against colonization by pathogenic microorganisms. Several factors can influence the intestinal microbiota; these include age, diet, inflammatory and infectious processes, and the use of antimicrobials. We investigated the influence of bacterial infection of the respiratory tract and of amoxicillin therapy on the normal intestinal microbiota of patients. Bacterial infectious processes affecting the respiratory tract were found to influence the intestinal microbiota, significantly decreasing the number of colony-forming units (CFUs) of Bacteroides spp. and Lactobacillus spp. per gram of feces. The use of amoxicillin also influenced the intestinal microbiota, significantly decreasing the CFU of Bifidobacterium spp. and Lactobacillus spp. /g of feces. Changes in the composition of the intestinal microbiota need to be observed, since a decrease in the normal microorganisms can pose a number of hazards for hosts, including decreased resistance to colonization. With proper follow-up, health-care teams can minimize such hazards by implementing suitable therapy- and diet-related measures, thus reducing the occurrence of detrimental effects on the gastrointestinal ecosystem.

Sensibilidad in vitro de microorganismos anaeróbicos / In vitro sensibility of anaerobic microbial

Los estudios in vitro de sensibilidad antibiótica frente a bacterias anaeróbicas son escasos en nuestro medio. El presente trabajo evaluó la actividad antimicrobiana de seis antibióticos frente a 301 cepas de microorganismos anaeróbicos. Destaca la sensibilidad del grupo Bacteroides fragilis grupo, frente a la clindamicina, en especial cuando se compara con la actividad de metronidazol. Los Bacteroides melaninogenicus presentan una resistencia de 33% al metranidazol, condición que no está descrita en la literatura extranjera. La penicilina y el cloramfenicol son los más activos frente a los microorganismos Gram positivos anaeróbicos. La actividad de metronidazol frente a este grupo de microorganismos es la más baja de todos los antibióticos estudiados. La clindamicina, el cloramfenicol y los nitroimidazólicos presentan mejor actividad que la penicilina frente a los Clostrium perfringens

Meningitis por bacteroides distasonis / Bacteroides distasonis meningitis

Se present ael caso de una paciente de 50 años que durante la internación por un severo cuadro de artritis reumatoidea, desarrolló una bacteriemia por Bacteroides distasonis a partir de una colecistitis no reconocida y cuya expresión final fue una meningitis. La evolución de la paciente no fue favorable por no haber recibido la terapia antibiótica adecuada en forma temprana. El diagnóstico etiológico fue realizado a través del estudio microbiológico del líquido cefalorraquídeo transportado y cultivado en aero y anaerobiosis. Este procedimiento es importante en aquellos pacientes que presentan procesos infecciosos agudos o crónicos pulmonares, intraabdominales o craneofaciales y que además son inmunocomprometidos. En tales casos debe incorporarse al esquema terapéutico inicial un antibiótico efectivo en el tratamiento de los gérmenes anaerobios que pudieran estar involucrados

Anaerobic flora in trophic ulcers in leprosy patients.

Material from 108 trophic ulcers from leprosy cases were studied bacteriologically. 4 cases showed growth of pure anaerobes and 69 showed mixed growth of aerobic and anaerobic bacteria. The predominant anaerobes were Fusobacteria (41), anaerobic cocci (30) and Bacteroides (25). Clostridia were isolated only in 10 cases. Metronidazole, chloramphenicol, penicillin and ampicillin were found effective against anaerobes in in-vitro studies.