OBJECTIVES:

To compare the antimicrobial susceptibility of Prevotella spp. isolated from cystic fibrosis (CF) and non-CF patients and analyse the impact of antibiotic prescribing in the preceding year on resistance amongst CF isolates.

METHODS:

The susceptibility of 80 CF Prevotella isolates to 12 antibiotics was compared with that of 50 Prevotella isolates from invasive infections in people who did not have CF and 27 Prevotella isolates from healthy controls.

RESULTS:

All isolates were susceptible to chloramphenicol, meropenem and piperacillin/tazobactam, with only four isolates resistant to metronidazole. However, resistance to amoxicillin, ceftazidime and tetracycline was apparent in all groups. Significant differences in clindamycin resistance (UK CF, 56%; UK invasive, 10%) and co-amoxiclav non-susceptibility (UK CF, 32%; UK invasive, 12%) were observed between UK CF and UK invasive isolates. The likelihood of non-susceptibility to clindamycin and co-amoxiclav in UK CF isolates was 5.5-fold and 2.5-fold higher relative to that in UK invasive isolates, respectively. Azithromycin MICs were also significantly higher for CF isolates (P < 0.001), which was associated with current prescription of azithromycin. More than 50% of clinical isolates tested in this study were β-lactamase positive.

CONCLUSIONS:

This study profiles antibiotic susceptibility in Prevotella spp. in CF and demonstrates that meropenem, piperacillin/tazobactam, chloramphenicol and metronidazole are likely to be the most effective antibiotics if treatment is indicated.

OBJECTIVE:

To investigate the effect of the microbiota-induced changes and early overfeeding after amoxicillin administration (a) in suckling pups via their dams up to 15 days of lactation and (b) in weaned pups on intestinal microbial/functional adaptability and obesity development in male Sprague-Dawley rats.

DESIGN AND METHODS:

Postnatal nutrition was elicited by adjusting the number of pups in the nest to 4 (small litters [SLs]) and 10 (normal litters [NLs]), while from days 21 to 40, both groups were fed with a standard diet. The numbers of Bacteroides/Prevotella (BAC) and Lactobacillus/Enterococcus (LAB) in the jejunum and colon were determined by fluorescence in situ hybridization technique, and jejunal alkaline phosphatase (AP), α-glucosidase and aminopeptidase activity was assayed histochemically.

RESULTS:

On day 40, the SL in comparison with NL animals displayed excess weight/fat gain accompanied by higher LAB and lower numbers of BAC, and with permanently higher AP activity. Moreover, these acquired changes continued in SL vs. NL rats and were not influenced by antibiotic treatment, which induced significant decrease in the quantity of LAB and BAC.

CONCLUSIONS:

These findings highlight the role of early life overfeeding upon the gut microbial/functional ontogeny and allow to distinguish their potential involvement in later risk of obesity.

PURPOSE:

Eradication rates following standard triple therapy for Helicobacter pylori infection are declining. Recent studies, conducted in a number of countries, have shown that sequential therapy for H. pylori infection yields high cure rates.

AIM:

To compare the efficacy and tolerability of a sequential regimen as a first-line treatment of H. pylori infection with a standard triple treatment regime in Morocco.

METHODS:

A total of 281 naive H. pylori-infected patients, confirmed by histological examination, were assigned randomly to one of two treatment groups: standard triple therapy [omeprazole (20 mg bid) + amoxicillin (1 g bid) + clarithromycin (500 mg bid) for 7 days] or sequential therapy [omeprazole (20 mg bid) + amoxicillin (1 g bid) for 5 days, followed by omeprazole (20 mg bid) + tinidazole (500 mg bid) + clarithromycin (500 mg bid) for an additional 5 days]. H. pylori eradication was checked 4-6 weeks after treatment initiation by using a (13)C-urea breath test. Compliance and adverse events were assessed.

RESULTS:

The two groups did not differ significantly in gender, age, previous disease history, endoscopic and histological features and smoking. The intention-to-treat and per-protocol eradication rates were 65.9 and 71 % in the standard triple therapy group, and 82.8 and 89.9 % in the sequential therapy group, respectively. The eradication rate was significantly higher in the sequential therapy group than in the standard triple therapy group (p < 0.001), There was no statistically significant difference in compliance (97.5  vs. 96.3 %) and incidence of side-effects (27.5 vs. 27.9 %) between the two groups.

CONCLUSIONS:

Based on our results, we conclude that for eradication of H. pylori infection, the 10-day sequential therapy is more effective than the standard triple therapy and is equally tolerated. These results confirm those of other studies in other countries.

PURPOSE:

: Our goals are to test the effect of acute lung infection on tumor metastasis and to investigate the underlying mechanisms. EXPERIMENTAL

DESIGN:

We combined bacteria- and lipopolysaccharide (LPS)-induced acute lung injury/inflammation (ALI) mouse models with mouse metastatic models to study the effect of acute inflammation on lung metastasis in mice. The mechanisms were invested in ex vivo, in vitro, and in vivo studies.

RESULTS:

Both bacteria- and LPS-induced acute lung injury/inflammation significantly enhanced lung metastasis of four tail vein-injected mouse tumor cell lines. Bacteria also enhanced lung metastasis when 4T1 cells orthotopically injected. The broncheoalveolar lavage fluid (BALF) from LPS- or bacteria- injected mice stimulated migration of tumor cells. In vivo tracking of metastatic RM-9 cells showed that bacterial injection enhanced early dissemination of tumor cells to the lung. The majority of the BALF migratory activity could be blocked by AMD3100, a CXCR4 inhibitor. All tested cell lines expressed CXCR4. The levels of extracellular ubiquitin (Ub), but not SDF-1, in BALF were significantly increased by LPS. Ub was able to induce AMD3100-sensitive migration of tumor cells. Finally, the anti-bacterial amoxicillin and AMD3100 blocked the enhancement effect of bacterial infection on tumor metastasis.

CONCLUSIONS:

Acute lung infection dramatically increased cancer cell homing to the lung and lung metastasis. This may be due to an alteration of the lung microenvironment and preparation of a favorable metastatic "niche". This effect was seen in multiple cancer types and thus may have broad applications for cancer patients in prevention and/or treatment of metastasis.

Background:

Chronic periodontitis patients may yield multiple species of putative periodontal bacterial pathogens that vary in their antibiotic drug susceptibility. This study determined the occurrence of in vitro antibiotic resistance among selected subgingival periodontal pathogens in chronic periodontitis patients.

Methods:

Subgingival biofilm specimens from inflamed deep periodontal pockets were removed prior to treatment from 400 adults in the United States with chronic periodontitis. The samples were cultured, and selected periodontal pathogens tested in vitro for susceptibility to amoxicillin at 8 mg/L, clindamycin at 4 mg/L, doxycycline at 4 mg/L, and metronidazole at 16 mg/L, with a post-hoc combination of data for amoxicillin and metronidazole. Gram-negative enteric rods/pseudomonads were subjected to ciprofloxacin disk diffusion testing.

Results:

Overall, 74.2% of the periodontitis patients revealed subgingival periodontal pathogens resistant to at least one of the test antibiotics. One or more test species, most often Prevotella intermedia/nigrescens, Streptococcus constellatus or Aggregatibacter actinomycetemcomitans, were resistant in vitro to doxycycline, amoxicillin, metronidazole, or clindamycin, in 55%, 43.3%, 30.3%, and 26.5% of the chronic periodontitis patients, respectively. 15% of patients harbored subgingival periodontal pathogens resistant to both amoxicillin and metronidazole, which were mostly either S. constellatus (45 persons) or ciprofloxacin-susceptible strains of gram-negative enteric rods/pseudomonads (nine persons).

Conclusions:

Chronic periodontitis patients in the United States frequently yielded subgingival periodontal pathogens resistant in vitro to therapeutic concentrations of antibiotics commonly utilized in clinical periodontal practice. The wide variability found in periodontal pathogen antibiotic resistance patterns should concern clinicians empirically selecting antibiotic treatment regimens for chronic periodontitis patients.

Intracranial complications of acute and chronic otitis media can be difficult to recognize, as signs and symptoms are often subtle and variable across different age groups. In March, 2012, a 10-year-old boy was hospitalized due to a 10-day history of horizontal double vision from the right eye, which worsened when looking towards the right side, initially neglected by his practitioner; in addition, a recurrent left-sided otitis media had been treated sequentially with cefpodoxime, amoxicillin, cefixime, and azithromycin in the foregoing month. On admission the boy was fully alert and had diplopia with complete right abducens palsy (AP). This article is protected by copyright. All rights reserved.

The aims of this study were to assess primary resistance of H. pylori strains isolated from adult patients of Ilam, Iran to antibacterial agents (amoxicillin, clarithromycin, metronidazole and tetracycline) and detection of clarithromycin, azithromycin, clarithromycin, metronidazole and tetracycline resistance by disc diffusion. Fifty biopsies were taken from gastric mucosa of the antrum and body regions of adult patients by gastroscopy, and were cultured on Helicobacter pylori selective medium. The susceptibility of H. pylori strains showed that 44, 6, 6, 4 and 16% were resistance to metronidazole, amoxicillin, tetracycline, azithromycin, and clarithromycin, respectively. Polymerase chain reaction- restriction fragment length polymorphism analysis showed that all clarithromycin resistance isolates had A2143G mutation and PCR amplicons from these strains upon digestion by BsaI restriction enzyme resulted in 319 and 106 base pair fragments. Because most of physicians in Ilam do not use amoxicillin in triple therapy of H. pylori infection, isolates showed low rate of resistance to amoxicillin.