Safety and Tolerability of Fluoroquinolones in Patients with Staphylococcal Periprosthetic Joint Infections

Dissemination of IncC plasmids in Salmonella enterica serovar Thompson recovered from seafood and human diarrheic patients in China

Salmonella Thompson is a prevalent foodborne pathogen and a major threat to food safety and public health. This study aims to reveal the dissemination mechanism of S. Thompson with co-resistance to ceftriaxone and ciprofloxacin. In this study, 181 S. Thompson isolates were obtained from a retrospective screening on 2118 serotyped Salmonella isolates from foods and patients, which were disseminated in 12 of 16 districts in Shanghai, China. A total of 10 (5.5 %) S. Thompson isolates exhibited resistance to ceftriaxone (MIC ranging from 8 to 32 μg/mL) and ciprofloxacin (MIC ranging from 2 to 8 μg/mL). The AmpC β-lactamase gene blaCMY-2 and plasmid-mediated quinolone resistance (PMQR) genes of qnrS and qepA were identified in the 9 isolates. Conjugation results showed that the co-transfer of blaCMY-2, qnrS, and qepA occurred on the IncC plasmids with sizes of ∼150 (n = 8) or ∼138 (n = 1) kbp. Three typical modules of ISEcp1-blaCMY-2-blc-sugE, IS26-IS15DIV-qnrS-ISKpn19, and ISCR3-qepA-intl1 were identified in an ST3 IncC plasmid pSH11G0791. Phylogenetic analysis indicated that IncC plasmids evolved into Lineages 1, 2, and 3. IncC plasmids from China including pSH11G0791 in this study fell into Lineage 1 with those from the USA, suggesting their close genotype relationship. In conclusion, to our knowledge, it is the first report of the co-existence of blaCMY-2, qnrS, and qepA in IncC plasmids, and the conjugational transfer contributed to their dissemination in S. Thompson. These findings underline further challenges for the prevention and treatment of Enterobacteriaceae infections posed by IncC plasmids bearing blaCMY-2, qnrS, and qepA.

Role of Routine Suppressive Antibiotic Therapy After Debridement, Antibiotics, and Implant Retention for Acute Periprosthetic Joint Infections

Background

The first-line management strategy for acute periprosthetic joint infections (PJIs) is debridement, antibiotics, and implant retention (DAIR). Suppressive antibiotic therapy (SAT) after DAIR is proposed to improve outcomes, yet its efficacy remains under scrutiny.

Methods

We conducted a multicenter retrospective study in patients with acute PJI of the hip or knee who were treated with DAIR in centers from Europe and the United States. We analyzed the effect of SAT using a Cox model landmarked at 12 weeks. The primary covariate of interest was SAT, which was analyzed as a time-varying covariate. Patients who experienced treatment failure or were lost to follow-up within 12 weeks were excluded from the analysis.

Results

The study included 510 patients with 66 treatment failures with a median follow-up of 801 days. We did not find a statistically significant association between SAT and treatment failure (hazard ratio, 1.37; 95% CI, .79-2.39; P = .27). Subgroup analyses for joint, country cohort, and type of infection (early or late acute) did not show benefit for SAT. Secondary analysis of country cohorts showed a trend toward benefit for the US cohort (hazard ratio, 0.36; 95% CI, .11-1.15; P = .09), which also had the highest risk of treatment failure.

Conclusions

The utility of routine SAT as a strategy for enhancing DAIR's success in acute PJI remains uncertain. Our results suggest that SAT's benefits might be restricted to specific groups of patients, underscoring the need for randomized controlled trials. Identifying patients most likely to benefit from SAT should be a priority in future studies.

Periprosthetic Joint Infection: Current Clinical Challenges

Over the last several decades, periprosthetic joint infection has been increasing in incidence and is occurring in more complex patients. While there have been advances in both surgical and medical treatment strategies, there remain important gaps in our understanding. Here, we share our current approaches to the diagnosis and management of periprosthetic joint infection, focusing on frequent clinical challenges and collaborative interdisciplinary care.

Rifampicin in periprosthetic joint infections: where do we stand and where are we headed?

INTRODUCTION

A periprosthetic joint infection (PJI) is a major complication of arthroplasty. Treatment of PJI consists of surgical debridement with or without the exchange of the implant and long-term antimicrobial treatment. Rifampicin is regarded as one of the cornerstones of antimicrobial treatment for staphylococcal PJI, but the exact role of rifampicin for PJI in different clinical scenarios remains to be elucidated.

AREAS COVERED

In this perspective article, an overview is provided of in vitro, in vivo and clinical studies that were the basis of the current guidelines and recommendations for rifampicin use in daily practice for PJI. Controversial issues on indication, dosing, timing, duration and antibiotic drug interactions will be addressed. Finally, the most urgent clinical questions on rifampicin use that need answering in the nearby future will be formulated.

EXPERT OPINION

Many inquiries remain concerning the exact indications and clinical use of rifampicin in PJI. Randomized controlled trials are needed to answer these questions.

Facilitating OPAT in rural areas

A sizable portion of the United States' population lives in a rural setting. Coupled with a limited number of infectious diseases providers, this has created a need for innovative practice models to deliver outpatient antimicrobial therapy and clinical monitoring in rural settings. This article reviews existing literature regarding outpatient parenteral antimicrobial therapy in rural settings and explores existing barriers and potential solutions that may be of assistance to providers looking to provide these services.

Cutibacterium acnes Prosthetic Joint Infections: Is Rifampicin-Combination Therapy Beneficial?

No consensus has been reached on the optimal antibiotic regimen to treat Cutibacterium acnes PJIs (Ca-PJIs). In vitro studies showed excellent rifampicin efficacy against biofilm-associated C. acnes infections, but clinical studies did not confirm the superiority of rifampicin-combined therapy over monotherapy. This prospective cohort study was undertaken to analyze the outcomes of 70 patients who underwent exchange arthroplasty for chronic monomicrobial Ca-PJI and were treated with rifampicin or without between 2004 and 2019. The 37 patients treated from January 2004 to August 2014 were prescribed rifampicin-combination therapy and the 33 treated from September 2014 to December 2019 received monotherapy without rifampicin. The primary endpoint was the 2-year Kaplan-Meier-estimated reinfection-free probability, including relapses and new-pathogen PJIs. The 2-year reinfection-free rate was high and not different for patients who had received rifampicin or not (89.2% vs. 93.8%, respectively; p = 0.524). None of the patients relapsed and six developed new-pathogen PJIs. Our results do not support a benefit of rifampicin-combination therapy for patients who underwent exchange arthroplasty for chronic Ca-PJIs.

Adjunctive Rifampin Following Debridement and Implant Retention for Staphylococcal Prosthetic Joint Infection: Is it Effective if not Combined With a Fluoroquinolone?

Whether rifampin benefits retained staphylococcal prosthetic joint infection is unsettled. In a meta-analysis of 8 studies, we found greater clinical cure with fluoroquinolone-rifampin vs all other regimens (odds ratio [OR], 2.68; 95% CI, 1.43-5.02), but no greater cure with other rifampin combinations vs regimens without rifampin (OR, 1.22; 95% CI, 0.79-1.88).

What Is the Best Oral Therapy for Staph aureus Osteomyelitis?

Best Oral Therapy for Staph aureus OsteomyelitisA 50-year-old patient with diabetes mellitus has a plantar ulcer at the base of the first metatarsal. Cortical erosions are noted; bone biopsy culture yields Staphylococcus aureus susceptible to methicillin, ciprofloxacin, clindamycin, doxycycline, trimethoprim/sulfamethoxazole, linezolid, and rifampin. The plan is for 4 weeks of antibiotic treatment. Which antibiotic should be prescribed?

Truth in DAIR: Duration of Therapy and the Use of Quinolone/Rifampin-Based Regimens following Debridement and Implant Retention for Periprosthetic Joint Infections

Background

The optimal duration of antibiotic therapy after debridement and implant retention (DAIR) for periprosthetic joint infections (PJIs) is debated. Furthermore, the best antibiotic regimens for staphylococcal PJI are also unclear. In this study, we evaluated the impact of antibiotic therapy duration on the risk of failure. We assessed the utility of rifampin-based regimens for staphylococcal PJI managed with DAIR.

Methods

We performed a retrospective cohort study of patients 18 years and older diagnosed with hip and knee PJI who underwent DAIR between January 1, 2008 and 31 December 31, 2018 at Mayo Clinic, USA. The outcome was failure of DAIR. For statistical analysis, joint-stratified Cox regression models adjusted for age, sinus tract, symptom duration, and primary/revision arthroplasty were performed.

Results

We examined 247 cases of PJI with a median follow-up of 4.4 years (interquartile range [IQR], 2.3–7) after DAIR. The estimated 5-year cumulative incidence of failure was 28.1% (n = 65). There was no association between the duration of intravenous (IV) antibiotics (median 42 days; IQR, 38–42) and treatment failure (P = .119). A shorter duration of subsequent oral antibiotic therapy was associated with a higher risk of failure (P = .005; eg, 90-day vs 1-year duration; hazard ratio [HR], 3.50; 95% confidence interval [CI], 1.48–8.25). For staphylococcal knee PJI, both the use and longer duration of a rifampin-based regimen were associated with a lower risk of failure (both P = .025). There was no significant association between fluoroquinolone (FQ) use and failure (HR, 0.62; 95% CI, .31–1.24; P = .172).

Conclusions

The duration of initial IV antibiotic therapy did not correlate with treatment failure in this cohort of patients. Rifampin use is recommended for staphylococcal knee PJI. There was no apparent benefit of FQ use in staphylococcal PJI.

Fusidic acid in a tertiary hospital: an observational study focusing on prescriptions, tolerance and susceptibility of Staphylococcus and Cutibacterium spp. strains from bone samples

Adverse drug reactions of broad-spectrum fluoroquinolones or rifampicin are not uncommon during osteomyelitis and orthopaedic implant infections (OOII). Thus, we made an overview (i) of the prescription of fusidic acid (FA) and (ii) of FA susceptibility of Staphylococcus sp. and Cutibacterium sp. strains isolated from bone samples. All prescriptions of FA and all bone samples with positive culture for Staphylococcus sp. or Cutibacterium sp. (Reims University Hospital June 2017-May 2021) were included. All Staphylococcus aureus strains were considered as significant, whereas Coagulase-negative Staphylococcus and Cutibacterium spp. strains were not if these strains grew only on one sole sample. The antibiotic susceptibility of Staphylococcus sp. strains and the susceptibility to FA of Cutibacterium sp. strains had been determined using disk diffusion methods, as described for Staphylococcus sp. in the CASFM/EUCAST guidelines. The mean FA consumption was 0.6 daily defined doses/1000 patient days. FA was prescribed for OOII due to Staphylococcus sp. and Cutibacterium sp. in 24 and 2 cases, respectively. Among 401 Staphylococcus sp. strains, there were 254 S. aureus (63.3%), 84 methicillin-resistant (20.9%) and 333 FA-susceptible (83.0%) strains. S. aureus and methicillin-sensitive strains were more likely to be susceptible to FA (p < 0.001). Among 39 Cutibacterium sp. strains, the FA inhibition zone diameter geometric mean was 28.6 mm (24-35 mm), suggesting that all these strains could be considered as susceptible to FA. These data suggested that FA could be more frequently used in OOII due to Staphylococcus sp. and Cutibacterium sp., subject to the absence of other resistant bacteria.

A Bundle of the Top 10 OPAT Publications in 2021

As outpatient parenteral antimicrobial therapy (OPAT) becomes more common, it may be difficult to stay current with recent related publications. A group of multidisciplinary OPAT clinicians reviewed and ranked all OPAT publications published in 2021. This article provides a high-level summary of the OPAT manuscripts that were voted the “top 10” publications of 2021.

Clindamycin Efficacy for Cutibacterium acnes Shoulder Device-Related Infections

Clindamycin is an antibiotic with high bioavailability and appropriate bone diffusion, often proposed as an alternative in guidelines for C. acnes prosthetic joint infections. We aimed to evaluate the efficacy of clindamycin in the treatment of C. acnes shoulder implant joint infections (SIJI). Methods: A retrospective analysis was conducted at the University Hospital of Nice (France) between 2010 and 2019. We included patients with one shoulder implant surgical procedure and at least one C. acnes positive sample. We selected the C. acnes SIJI according to French and international recommendations. The primary endpoint was favorable outcome of C. acnes SIJI treatment after at least 1-year follow-up in the clindamycin group compared to another therapeutic group. Results: Forty-eight SIJI were identified and 33 were treated with clindamycin, among which 25 were treated with monotherapy. The median duration of clindamycin antibiotherapy was 6 weeks. The average follow-up was 45 months; one patient was lost to follow-up. Twenty-seven patients out of 33 (82%) were cured with clindamycin, compared to 9/12 (75%) with other antibiotics. The rate of favorable outcomes increased to 27/31 (87%) with clindamycin and to 9/10 (90%) for other antibiotics when no septic revision strategies were excluded (P = 1.00). Conclusions: The therapeutic strategy based on one- or two-stage revision associated with 6 weeks of clindamycin seems to be effective.

Survey of pharmacists on their roles and perceptions of outpatient parenteral antimicrobial therapy in the United States

OBJECTIVES

To define outpatient parenteral antimicrobial therapy (OPAT) clinical pharmacy practice across the United States, specifically pharmacist functions, design of pharmacist involvement, and to compare pharmacist training of those who practice in OPAT to infectious diseases pharmacists who do not.

METHODS

A survey of a possible 32 questions was emailed to the American College of Clinical Pharmacists (ACCP) Infectious Diseases Practice and Research Network (PRN) e-mail list. Results were focused on US-based respondents.

PARTICIPANTS

In total, 87 pharmacists responded; 27 of these pharmacists (31%) practiced in OPAT.

RESULTS

Training background did not differ between groups. Programs with an OPAT pharmacist were more likely to have a formal OPAT team compared to those without an OPAT pharmacist (P < .001). OPAT pharmacists were early in their careers with 66.7% practicing <5 years in OPAT. Most OPAT pharmacists (66.7%) practiced at an academic medical center with a median full-time equivalent (FTE) of 0.6. Moreover, 63% utilized a collaborative practice agreement and 81.5% shared job functions with other pharmacist roles, most commonly antimicrobial stewardship. Few OPAT programs involved a dispensing component (28%). The median daily census was 43 patients followed by an OPAT pharmacist. Pharmacists performed a variety of tasks in OPAT.

CONCLUSION

Pharmacist nondispensing involvement in OPAT is an emerging trend in the United States with wide variability in program structure and pharmacist tasks. A ratio of 1 OPAT pharmacist for every 45-70 OPAT patients is proposed to facilitate expansion of pharmacist clinical practice in OPAT.

Antibiotic Therapy for Prosthetic Joint Infections: An Overview

Prosthetic joint infection (PJI) is a severe complication after arthroplasty. Its management combines surgical intervention, whose type depends on the clinical situation, and prolonged high-dose antibiotics adapted to the responsible microorganism(s) and the patient. Antibiotics are only one part of the therapeutic regimen and are closely related to the surgical strategy. Their efficacy depends to a large extent on the choice and quality of the surgical procedure, and the quality of the microbiological diagnosis. Although guidelines have been published, many aspects of antibiotic therapy remain poorly established. Choosing the optimal agent(s) is one aspect, with others being optimization of drugs’ pharmacokinetic/pharmacodynamic parameters, the choice of administration route, use of monotherapy or combination regimens, therapeutic drug-monitoring and patient education to improve compliance and tolerance. Herein, we address PJI management based on recent literature data, guidelines and the experience of our referral center for complex bone-and-joint infections.

Insulinotropic Potential of Moxifloxacin and Gemifloxacin: An In Vivo Rabbits Model Study Followed by Randomized Phase I Clinical Trial

Fluoroquinolones (FQs) have been reported to cause dysglycemia in both diabetic and non-diabetic patients. However, diabetic patients are usually on polypharmacy, so we cannot attribute the dysglycemia specifically to FQs. To answer the question as to whether Moxifloxacin and Gemifloxacin influence blood glucose levels and serum insulin levels or otherwise, rabbits were used as experimental animals in an in vivo model followed by a phase I randomized clinical trial in euglycemic healthy volunteers. The effects on the serum insulin and blood glucose levels in the Moxifloxacin and Gemifloxacin treated groups were, respectively, determined on the fifth day in both the in-vivo rabbits model and in the test subjects of the phase I clinical trial. The effects of these drugs were also checked on the histomorphology of the pancreas in the rabbits. The findings of our study suggest that Moxifloxacin and Gemifloxacin significantly (p < 0.05) reduced the blood glucose levels via a subsequent significant shift in the serum insulin levels both in the in vivo animal model and in the test subjects of the phase I clinical trial. No prominent effects on the beta cells histomorphology were noted in this study. Moxifloxacin showed a more significant effect than Gemifloxacin. The insulinotropic effect was comparable to the effect of Glibenclamide. It is concluded that Moxifloxacin and Gemifloxacin have a significant blood glucose lowering effect mediated through insulinotropic action. (Clinical Trials.gov identifier: NCT04692623).

Implementation of a consensus protocol for antibiotic use for bone and joint infection to reduce unnecessary outpatient parenteral antimicrobial therapy: A quality improvement initiative

Objective:

We aimed to decrease the use of outpatient parenteral antimicrobial therapy (OPAT) for patients admitted for bone and joint infections (BJIs) by applying a consensus protocol to suggest oral antibiotics for BJI.

Design:

A quasi-experimental before-and-after study.

Setting:

Inpatient setting at a single medical center.

Patients:

All inpatients admitted with a BJI.

Methods:

We developed a consensus table of oral antibiotics for BJI among infectious diseases (ID) specialists. Using the consensus table, we implemented a protocol consisting of a weekly reminder e-mail and case-based discussion with the consulting ID physician. Outcomes of patients during the implementation period (November 1, 2020, to May 31, 2021) were compared with those during the preimplementation period (January 1, 2019, to October 31, 2020). Our primary outcome was the proportion of patients treated with OPAT. Secondary outcomes included length of hospital stay (LOS) and recurrence or death within 6 months.

Results:

In total, 77 patients during the preimplementation period and 22 patients during the implementation period were identified to have a BJI. During the preimplementation period, 70.1% of patients received OPAT, whereas only 31.8% of patients had OPAT during the implementation period (P = .003). The median LOS after final ID recommendation was significantly shorter during the implementation period (median 3 days versus 1 day; P < .001). We detected no significant difference in the 6-month rate of recurrence (24.7% vs 31.8%; P = .46) or mortality (9.1% vs 9.1%; P = 1.00).

Conclusions:

More patients admitted with BJIs were treated with oral antibiotics during the implementation phase of our quality improvement initiative.

Recent Updates in Antimicrobial Stewardship in Outpatient Parenteral Antimicrobial Therapy

Purpose of Review

Antimicrobial stewardship within acute care is common and has been expanding to outpatient areas. Some inpatient antimicrobial stewardship tactics apply to outpatient parenteral antimicrobial therapy (OPAT) and complex outpatient antimicrobial therapy (COpAT) management, but differences do exist.

Recent Findings

OPAT/COpAT is a growing area of practice and research with its own unique considerations for antimicrobial stewardship. Potential ideas for antimicrobial stewardship in the OPAT/COpAT setting include redesigning the regimen to COpAT instead of OPAT, ensuring the use of the shortest effective duration of antimicrobial therapy; using antimicrobials dosed less frequently, such as long-acting glycopeptides; optimizing antimicrobial susceptibility testing reporting for common OPAT/COpAT drugs; and establishing routine laboratory and safety monitoring. Future consensus is needed to determine validated OPAT program metrics and outcomes.

Summary

As more focus is placed on outpatient antimicrobial stewardship, clinicians practicing in OPAT should publish more data regarding OPAT program methods and outcomes as they relate to antimicrobial stewardship. These can involve patient clinical outcomes, OPAT readmission rates, OPAT therapy completion, and central line-related complications.

Impact of Generic Entry on Hospital Antimicrobial Use: A Retrospective Quasi-Experimental Interrupted Time Series Analysis

Background: The impact of antimicrobials generic entry (GE) is controversial. Their introduction could provide an economic benefit yet may also increase their consumption, leading to a higher risk of resistance. Our aim was to analyze the impact of GE on trends of antimicrobial consumption in an acute-care hospital. Methods: A retrospective quasi-experimental interrupted time series analysis was conducted at a 400-bed tertiary hospital in Barcelona, Spain. All antimicrobials for systemic use for which a generic product entered the hospital from January 2000 to December 2019 were included. Antimicrobial consumption was expressed as DDD/100 bed days. Results: After GE, the consumption of cefotaxime (0.09, p < 0.001), meropenem (0.54, p < 0.001), and piperacillin-tazobactam (0.13, p < 0.001) increased, whereas the use of clindamycin (−0.03, p < 0.001) and itraconazole (−0.02, p = 0.01) was reduced. An alarming rise in cefepime (0.004), daptomycin (1.02), and cloxacillin (0.05) prescriptions was observed, despite not achieving statistical significance. On the contrary, the use of amoxicillin (−0.07), ampicillin (−0.02), cefixime (−0.06), fluconazole (−0.13), imipenem–cilastatin (−0.50) and levofloxacin (−0.35) decreased. These effects were noticed beyond the first year post GE. Conclusions: GE led to an increase in the consumption of broad-spectrum molecules. The potential economic benefit of generic antibiotics could be diluted by an increase in resistance. Antimicrobial stewardship should continue to monitor these molecules despite GE.

Outcome of Debridement, Antibiotics, and Implant Retention for Staphylococcal Hip and Knee Prosthetic Joint Infections, Focused on Rifampicin Use: A Systematic Review and Meta-Analysis

The treatment of staphylococcal prosthetic joint infection (PJI) with debridement, antibiotics, and retention of the implant (DAIR) often results in failure. An important evidence gap concerns the treatment with rifampicin for PJI. A systematic review and meta-analysis were conducted to assess the outcome of staphylococcal hip and/or knee PJI after DAIR, focused on the role of rifampicin. Studies published until September 2, 2020 were included. Success rates were stratified for type of joint and type of micro-organism. Sixty-four studies were included. The pooled risk ratio for rifampicin effectiveness was 1.10 (95% confidence interval, 1.00-1.22). The pooled success rate was 69% for Staphylococcus aureus hip PJI, 54% for S aureus knee PJI, 83% for coagulase-negative staphylococci (CNS) hip PJI, and 73% for CNS knee PJI. Success rates for MRSA PJI (58%) were similar to MSSA PJI (60%). The meta-analysis indicates that rifampicin may only prevent a small fraction of all treatment failures.