Bioavailability of oral ciprofloxacin in early postsurgical patients

Antibiotic-induced gut dysbiosis and cognitive, emotional, and behavioral changes in rodents: a systematic review and meta-analysis

There are previous epidemiological studies reporting associations between antibiotic use and psychiatric symptoms. Antibiotic-induced gut dysbiosis and alteration of microbiota-gut-brain axis communication has been proposed to play a role in this association. In this systematic review and meta-analysis, we reviewed published articles that have presented results on changes in cognition, emotion, and behavior in rodents (rats and mice) after antibiotic-induced gut dysbiosis. We searched three databases-PubMed, Web of Science, and SCOPUS to identify such articles using dedicated search strings and extracted data from 48 articles. Increase in anxiety and depression-like behavior was reported in 32.7 and 40.7 percent of the study-populations, respectively. Decrease in sociability, social novelty preference, recognition memory and spatial cognition was found in 18.1, 35.3, 26.1, and 62.5 percent of the study-populations, respectively. Only one bacterial taxon (increase in gut Proteobacteria) showed statistically significant association with behavioral changes (increase in anxiety). There were no consistent findings with statistical significance for the potential biomarkers [Brain-derived neurotrophic factor (BDNF) expression in the hippocampus, serum corticosterone and circulating IL-6 and IL-1β levels]. Results of the meta-analysis revealed a significant association between symptoms of negative valence system (including anxiety and depression) and cognitive system (decreased spatial cognition) with antibiotic intake (p < 0.05). However, between-study heterogeneity and publication bias were statistically significant (p < 0.05). Risk of bias was evaluated to be high in the majority of the studies. We identified and discussed several reasons that could contribute to the heterogeneity between the results of the studies examined. The results of the meta-analysis provide promising evidence that there is indeed an association between antibiotic-induced gut dysbiosis and psychopathologies. However, inconsistencies in the implemented methodologies make generalizing these results difficult. Gut microbiota depletion using antibiotics may be a useful strategy to evaluate if and how gut microbes influence cognition, emotion, and behavior, but the heterogeneity in methodologies used precludes any definitive interpretations for a translational impact on clinical practice.

A Physiologically-Based Pharmacokinetic Model to Describe Ciprofloxacin Pharmacokinetics Over the Entire Span of Life

Background

Physiologically-based pharmacokinetic (PBPK) modeling has received growing interest as a useful tool for the assessment of drug pharmacokinetics by continuous knowledge integration.

Objective

The objective of this study was to build a ciprofloxacin PBPK model for intravenous and oral dosing based on a comprehensive literature review, and evaluate the predictive performance towards pediatric and geriatric patients.

Methods

The aim of this report was to establish confidence in simulations of the ciprofloxacin PBPK model along the development process to facilitate reliable predictions outside of the tested adult age range towards the extremes of ages. Therefore, mean data of 69 published clinical trials were identified and integrated into the model building, simulation and verification process. The predictive performance on both ends of the age scale was assessed using individual data of 258 subjects observed in own clinical trials.

Results

Ciprofloxacin model verification demonstrated no concentration-related bias and accurate simulations for the adult age range, with only 4.8% of the mean observed data points for intravenous administration and 12.1% for oral administration being outside the simulated twofold range. Predictions towards the extremes of ages for the area under the plasma concentration–time curve (AUC) and the maximum plasma concentration (C_max) over the entire span of life revealed a reliable estimation, with only two pediatric AUC observations outside the 90% prediction interval.

Conclusion

Overall, this ciprofloxacin PBPK modeling approach demonstrated the predictive power of a thoroughly informed middle-out approach towards age groups of interest to potentially support the decision-making process.

Electronic supplementary material

The online version of this article (10.1007/s40262-018-0661-6) contains supplementary material, which is available to authorized users.

Improvements in Antimicrobial Prescribing and Outcomes in Pediatric Complicated Appendicitis

BACKGROUND

Complicated appendicitis, characterized by perforation and/or peritonitis, is common in children, and late infectious complications are frequent. The best antibiotic treatment approach is unknown, resulting in substantial variation in care. We evaluated the effects of 2 successive interventions, an antimicrobial stewardship program (ASP) and a condition-specific clinical practice guideline (CPG), on antimicrobial utilization and patient outcomes in these patients.

METHODS

The ASP at our institution was begun in March 2012. The CPG, a standardized antibiotic treatment, was implemented in July 2013. We reviewed every case of complicated appendicitis managed with early appendectomy between January 2011 and October 2014. Patients were thus divided into 3 eras based on their exposure to the following: (1) neither intervention, (2) ASP only or (3) both ASP and CPG. We compared measures of antibiotic utilization and clinical outcomes among the 3 eras.

RESULTS

A total of 313 patients were included in the study: 91 exposed to neither intervention; 100 exposed to only the ASP; and 122 exposed to both interventions. With ASP implementation, there were declines in the use of unnecessarily broad or toxic antibiotic regimens. With CPG implementation, there was a decrease in total antibiotic utilization and discharges with intravenous antibiotics. Compliance with CPG-recommended antibiotics exceeded 90%. There was no significant change in overall adverse events; there was a decline in the incidence of surgical-site infections in patients exposed to both interventions.

CONCLUSIONS

Complicated appendicitis is an important target for antimicrobial stewardship and quality improvement efforts. A condition-specific CPG can improve both antimicrobial utilization and clinical outcomes.

Antistaphylococcal activities of the new fluoroquinolone JNJ-Q2

The new broad-spectrum fluoroquinolone JNJ-Q2 displays in vitro activity against Gram-negative and Gram-positive organisms, including methicillin-resistant Staphylococcus aureus (MRSA) and ciprofloxacin-resistant MRSA isolates. Tested with isogenic methicillin-susceptible S. aureus (MSSA) and MRSA strains bearing quinolone-resistant target mutations, JNJ-Q2 displayed MICs ≤ 0.12 μg/ml, values 16- to 32-fold lower than those determined for moxifloxacin. Overexpression of the NorA efflux pump did not impact JNJ-Q2 MICs. Inhibition of S. aureus DNA gyrase and DNA topoisomerase IV enzymes demonstrated that JNJ-Q2 was more potent than comparators against wild-type enzymes and enzymes carrying quinolone-resistant amino acid substitutions, and JNJ-Q2 displayed equipotent activity against both enzymes. In serial-passage studies comparing resistance selection in parallel MRSA cultures by ciprofloxacin and JNJ-Q2, ciprofloxacin readily selected for mutants displaying MIC values of 128 to 512 μg/ml, which were observed within 18 to 24 days of passage. In contrast, cultures passaged in the presence of JNJ-Q2 displayed MICs ≤ 1 μg/ml for a minimum of 27 days of serial passage. A mutant displaying a JNJ-Q2 MIC of 4 μg/ml was not observed until after 33 days of passage. Mutant characterization revealed that ciprofloxacin-passaged cultures with MICs of 256 to 512 μg/ml carried only 2 or 3 quinolone resistance-determining region (QRDR) mutations. Cultures passaged with JNJ-Q2 selection for up to 51 days displayed MICs of 1 to 64 μg/ml and carried between 4 and 9 target mutations. Established in vitro biofilms of wild-type or ciprofloxacin-resistant MRSA exposed to JNJ-Q2 displayed greater decreases in bacterial counts (7 days of exposure produced 4.5 to >7 log(10) CFU decreases) than biofilms exposed to ciprofloxacin, moxifloxacin, rifampin, or vancomycin.

Systematic review: fluoroquinolones for the treatment of intra-abdominal surgical infections

BACKGROUND

Intra-abdominal infections result in substantial morbidity and mortality. Fluoroquinolones are among the various regimens that are used for the treatment of these infections.

AIM

To evaluate the available data from laboratory and clinical studies regarding the use of fluoroquinolones for the treatment of patients with intra-abdominal infections.

METHODS

We searched for relevant laboratory and clinical studies in the PubMed and the Cochrane Library databases.

RESULTS

Good pharmacokinetic and pharmacodynamic properties of fluoroquinolones in inflamed abdominal tissue are reported in several laboratory studies. In six prospective non-randomized clinical studies of patients with intra-abdominal infections, the clinical success achieved with the use of fluoroquinolones ranged from 77% to 94%. In 10 randomized-controlled trials fluoroquinolone-based regimens were compared with other commonly used (mainly beta-lactam-based) regimens. Clinical success, bacterial eradication, withdrawal because of toxicity and mortality were similar between the compared treatment arms except from two randomized-controlled trials, in which clinical success was statistically higher in the fluoroquinolone treatment arm.

CONCLUSIONS

Fluoroquinolones seem to be an effective and relatively safe option for the treatment of patients with intra-abdominal infections.

Interrupting drug therapy in the perioperative period

Millions of patients undergo surgery each year and an increasing proportion of these patients are consuming therapeutic drugs. Drug therapy is often withheld in the immediate perioperative period and after major surgery, in particular, there is often a prolonged period of fasting. This may lead to withdrawal effects including recurrence or worsening of patients' disease symptomatology. These effects will occur during a period of physiological and pathophysiological stresses and render patients more vulnerable to drug withdrawal phenomena. Thus, patients may be exposed to greater and sometimes unnecessary risks in the perioperative period. There are relatively few studies that have investigated this problem. The ones that have, however, confirm that drug abstinence in the perioperative period is a relatively common phenomenon and one study has demonstrated an association between duration of drug abstinence and adverse outcomes. The pathophysiological effects of major surgery on gastrointestinal function, neuro-humoral and cytokine adaptive responses to surgical stress are under-appreciated. These responses can reduce the effectiveness of oral administration and exacerbate co-existing disease processes. These problems are compounded by a fragmented approach to perioperative drug therapy with no one group of healthcare professionals assuming responsibility for this aspect of care. This may in part be a consequence of the complexities of rationalising drug therapy in the perioperative period together with the lack of readily available and evidence based information strategies for individual drugs or drug classes. An additional problem relates to the formulations, inherent pharmacokinetics and limited routes of administration of many prescribed drugs. These can prevent a 'seamless' transition from preoperative to postoperative management. Consumers, health professionals, pharmaceutical companies and drug regulatory agencies must all play a part in rectifying this problem. There remains a need for further research to clarify the effects of abstinence on patient outcomes and also to identify optimum strategies to avoid unwanted drug abstinence.