Improving linezolid use decreases the incidence of resistance among Gram-positive microorganisms

The impact of antibiotic stewardship interventions and patient related factors on antibiotic prescribing in a vascular surgical department

PURPOSE

The development of guidelines tailored to the departments' needs and counselling during ward rounds are important antibiotic stewardship (AS) strategies. The aim was to analyse the impact of AS ward rounds and institutional guidelines as well as patient-related factors on antibiotic use in vascular surgical patients.

METHODS

A retrospective prescribing-analysis of 3 months (P1, P2) before and after implementing weekly AS ward rounds and antimicrobial treatment guidelines was performed. Choice of systemic antibiotics, days of antibiotic therapy and clinical data were obtained from electronic patient records.

RESULTS

During P2, the overall antibiotic consumption as well as the use of last-resort compounds like linezolid and fluoroquinolones decreased distinctly (overall: 47.0 days of therapy (DOT)/100 patient days (PD) vs. 35.3 DOT/100PD, linezolid: 3.7 DOT/100PD vs. 1.0 DOT/100PD, fluoroquinolones: 7.0 DOT/100PD vs. 3.2 DOT/100PD) while narrow-spectrum beta-lactams increased by 48.4%. Courses of antibiotics were de-escalated more often during P2 (30.5% vs. 12.1%, p = 0.011). Only in P2, an antibiotic therapy was initiated in patients suffering from more comorbidities (i.e. higher Charlson Comorbidity Index) more frequently. Other patient factors had no distinct impact on antibiotic prescribing.

CONCLUSION

Weekly AS ward rounds improved adherence to institutional antibiotic treatment guidelines and antibiotic prescribing in vascular surgical patients. Clear patient-related determinants affecting choice of antibiotic therapies could not be identified.

Antibiotics prescription for targeted therapy of pediatric invasive pneumococcal diseases in China: a multicenter retrospective study

Background

Streptococcus pneumoniae (S. pneumoniae) is a major cause of bacterial meningitis, septicemia and pneumonia in children. Inappropriate choice of antibiotic can have important adverse consequences for both the individual and the community. Here, we focused on penicillin/cefotaxime non-susceptibility of S. pneumoniae and evaluated appropriateness of targeted antibiotic therapy for children with IPD (invasive pneumococcal diseases) in China.

Methods

A multicenter retrospective study was conducted in 14 hospitals from 13 provinces in China. Antibiotics prescription, clinical features and resistance patterns of IPD cases from January 2012 to December 2017 were collected. Appropriateness of targeted antibiotics therapy was assessed.

Results

806 IPD cases were collected. The non-susceptibility rates of S. pneumoniae to penicillin and cefotaxime were 40.9% and 20.7% respectively in 492 non-meningitis cases, whereas those were 73.2% and 43.0% respectively in 314 meningitis cases. Carbapenems were used in 21.3% of non-meningitis cases and 42.0% of meningitis cases for targeted therapy. For 390 non-meningitis cases with isolates susceptible to cefotaxime, vancomycin and linezolid were used in 17.9% and 8.7% of cases respectively for targeted therapy. For 179 meningitis cases with isolates susceptible to cefotaxime, vancomycin and linezolid were prescribed in 55.3% and 15.6% of cases respectively. Overall, inappropriate targeted therapies were identified in 361 (44.8%) of 806 IPD cases, including 232 (28.8%) cases with inappropriate use of carbapenems, 169 (21.0%) cases with inappropriate use of vancomycin and 62 (7.7%) cases with inappropriate use of linezolid.

Conclusions

Antibiotic regimens for IPD definite therapy were often excessive with extensive prescription of carbapenems, vancomycin or linezolid in China. Antimicrobial stewardship programs should be implemented to improve antimicrobial use.

Combined antibiotic stewardship and infection control measures to contain the spread of linezolid-resistant Staphylococcus epidermidis in an intensive care unit

Background

The unrestricted use of linezolid has been linked to the emergence of linezolid-resistant Staphylococcus epidermidis (LRSE). We report the effects of combined antibiotic stewardship and infection control measures on the spread of LRSE in an intensive care unit (ICU).

Methods

Microbiological data were reviewed to identify all LRSE detected in clinical samples at an ICU in southwest Germany. Quantitative data on the use of antibiotics with Gram-positive coverage were obtained in defined daily doses (DDD) per 100 patient-days (PD). In addition to infection control measures, an antibiotic stewardship intervention was started in May 2019, focusing on linezolid restriction and promoting vancomycin, wherever needed. We compared data from the pre-intervention period (May 2018–April 2019) to the post-intervention period (May 2019–April 2020). Whole-genome sequencing (WGS) was performed to determine the genetic relatedness of LRSE isolates.

Results

In the pre-intervention period, LRSE were isolated from 31 patients (17 in blood cultures). The average consumption of linezolid and daptomycin decreased from 7.5 DDD/100 PD and 12.3 DDD/100 PD per month in the pre-intervention period to 2.5 DDD/100 PD and 5.7 DDD/100 PD per month in the post-intervention period (p = 0.0022 and 0.0205), respectively. Conversely, vancomycin consumption increased from 0.2 DDD/100 PD per month to 4.7 DDD/100 PD per month (p < 0.0001). In the post-intervention period, LRSE were detected in 6 patients (4 in blood cultures) (p = 0.0065). WGS revealed the predominance of one single clone.

Conclusions

Complementing infection control measures by targeted antibiotic stewardship interventions was beneficial in containing the spread of LRSE in an ICU.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13756-021-00970-3.

The Impact of an Antibiotic Stewardship Program on the Consumption of Specific Antimicrobials and Their Cost Burden: A Hospital-wide Intervention

Background

Inappropriate use of antimicrobials (AM) is a major concern worldwide that leads to the propagation of antimicrobial resistance (AMR). In addition to its clinical implications, AMR imposes an economic burden on communities, especially developing countries with more infectious diseases and less available resources. Antimicrobial stewardship programs (ASPs) have been found to be effective in reducing AMR. This study was designed to evaluate the effect of implementing an ASP in reducing AM consumption, its economic burden, and AMR as a consecutive result.

Materials and Methods

Consumption of caspofungin, amphotericin B, voriconazole, colistin, linezolid, vancomycin, and carbapenems was compared in a prospective cross-sectional study between two time periods introduced as pre- and post-ASP. Drug use density presented as anatomical therapeutic chemical (ATC)/defined daily doses (DDD) and normalized per 1000 bed days, cost savings, and AMR patterns were evaluated.

Results

A total of 9400 AM prescriptions were analyzed during a 2-year period. Consumption measured in DDD/1000 bed days dropped by 24.8, 25.0, 35.3, 47.0, 39.2, 10.5, and 23.2 percent for amphotericin B, caspofungin, colistin, voriconazole, meropenem, imipenem, and vancomycin, respectively. Linezolid consumption increased by 26.8% after implementing ASP. The expenditure of target AMs in the average value of USD decreased by 41.3% after the intervention compared to the time before using ASP (P-value=0.001). Implementing ASP also increased AM susceptibility of Pseudomonas aeruginosa, while the susceptibility of methicillin-resistant Staphylococcus aureus did not change significantly.

Conclusion

The results of this study suggest that establishment of ASP can lead to a reduction in improper administration of AMs and their expenditure resulting in economic benefit and lowering AMR at hospitals with minimum resources. Clinical pharmacists' role was critical to the success of this ASP and was uniquely empowered at our center.

Microbes, Transmission Routes and Survival Outside the Body

Microbes like bacteria, virus, parasites and fungi may naturally colonize skin and mucous membranes without any sign of illness, for a longer or shorter period, in all humans, animals, fish, parasites, plants and all other living beings. Some types may be more invasive in human tissue than others. Many microbes are free-living in the environment—in water, soil and air and on equipment—as a part of the normal microbial flora on the Earth. Most of them are not dangerous and live in peaceful symbiosis with other living beings and may also be transferred between living species, from man to animal or man to plants and environment—and vice versa. New and old human pathogenic microbes are increasing all over the world. Some agents, like drug-resistant bacteria and highly pathogenic viruses, are more dangerous than others, and some microbes may cause chronic devastating diseases. Transmission routes depend on the robustness of the microbe in the environment, virulence, infectious dose, anatomical site in the body, etc. Pathogenic microbes are spread by contact, air, water, food, beverages, contaminated equipment and environment and are more seldom vector-borne, by insects or animals. The following chapter is focused on the most frequent pathogenic microbes, their preselected localization in the body, transmission routes and survival in the environment.

Effect of antibiotic stewardship on the incidence of infection and colonisation with antibiotic-resistant bacteria and Clostridium difficile infection: a systematic review and meta-analysis

BACKGROUND

Antibiotic stewardship programmes have been shown to reduce antibiotic use and hospital costs. We aimed to evaluate evidence of the effect of antibiotic stewardship on the incidence of infections and colonisation with antibiotic-resistant bacteria.

METHODS

For this systematic review and meta-analysis, we searched PubMed, the Cochrane Database of Systematic Reviews, the Cochrane Central Register of Controlled Trials, and Web of Science for studies published from Jan 1, 1960, to May 31, 2016, that analysed the effect of antibiotic stewardship programmes on the incidence of infection and colonisation with antibiotic-resistant bacteria and Clostridium difficile infections in hospital inpatients. Two authors independently assessed the eligibility of trials and extracted data. Studies involving long-term care facilities were excluded. The main outcomes were incidence ratios (IRs) of target infections and colonisation per 1000 patient-days before and after implementation of antibiotic stewardship. Meta-analyses were done with random-effect models and heterogeneity was calculated with the I² method.

FINDINGS

We included 32 studies in the meta-analysis, comprising 9 056 241 patient-days and 159 estimates of IRs. Antibiotic stewardship programmes reduced the incidence of infections and colonisation with multidrug-resistant Gram-negative bacteria (51% reduction; IR 0·49, 95% CI 0·35-0·68; p<0·0001), extended-spectrum β-lactamase-producing Gram-negative bacteria (48%; 0·52, 0·27-0·98; p=0·0428), and meticillin-resistant Staphylococcus aureus (37%; 0·63, 0·45-0·88; p=0·0065), as well as the incidence of C difficile infections (32%; 0·68, 0·53-0·88; p=0·0029). Antibiotic stewardship programmes were more effective when implemented with infection control measures (IR 0·69, 0·54-0·88; p=0·0030), especially hand-hygiene interventions (0·34, 0·21-0·54; p<0·0001), than when implemented alone. Antibiotic stewardship did not affect the IRs of vancomycin-resistant enterococci and quinolone-resistant and aminoglycoside-resistant Gram-negative bacteria. Significant heterogeneity between studies was detected, which was partly explained by the type of interventions and co-resistance patterns of the target bacteria.

INTERPRETATION

Antibiotic stewardship programmes significantly reduce the incidence of infections and colonisation with antibiotic-resistant bacteria and C difficile infections in hospital inpatients. These results provide stakeholders and policy makers with evidence for implementation of antibiotic stewardship interventions to reduce the burden of infections from antibiotic-resistant bacteria.

FUNDING

German Center for Infection Research.

Assessment of linezolid prescriptions in three French hospitals

The use of linezolid to treat gram-positive cocci infections is increasing in France. Linezolid is approved in pneumonia and complicated skin and soft tissue infections. Overuse and misuse of linezolid can favor the emergence and spreading of linezolid-resistant strains. We aimed to assess the appropriateness of linezolid use in French hospitals. This is a multicenter, retrospective study conducted in three tertiary care hospitals. Appropriateness of linezolid indications and adequacy (composite score concerning dosage, route of administration and blood monitoring) were assessed. Over a three-month period, all prescriptions of linezolid were extracted and analyzed by two independent infectious disease experts. Among the 81 initial prescriptions that were evaluated, indication was appropriate in 48% of cases. Among those, 51% complied with international guidelines. Fifty-seven percent of the prescriptions were adequate regarding dosage, route of administration and blood monitoring. Overall, 23% of prescriptions combined both appropriateness and adequacy. The most frequent reasons for inappropriateness were the possibility of choosing narrower-spectrum antibiotics and the empirical use of linezolid in severe sepsis or septic shock. Initial treatment was the most frequently appropriate in bone and joint infection cases (p = 0.001). Our study shows that even if modalities of use were mostly correct, appropriateness of linezolid indications is low. Educational programs are mandatory to improve practices, as well as clinical studies to better assess the efficacy and safety of linezolid in clinical situations other than pneumonia or complicated skin and soft tissue infections.

Impact of the PROVAUR stewardship programme on linezolid resistance in a tertiary university hospital: a before-and-after interventional study

BACKGROUND

There is little evidence of the impact of antimicrobial stewardship programmes on antimicrobial resistance.

OBJECTIVES

To study the efficacy and safety of a package of educational and interventional measures to optimize linezolid use and its impact on bacterial resistance.

METHODS

A quasi-experimental study was designed and carried out before and after implementation of a stewardship programme in hospitalized patients with Gram-positive infections treated with linezolid.

RESULTS

The intervention reduced linezolid consumption by 76%. The risk of linezolid-resistant CoNS isolates (OR = 0.37; 95% CI = 0.27-0.49; P < 0.001) and Enterococcus faecalis (OR = 0.44; 95% CI = 0.21-0.90; P = 0.03) during the intervention period was lower than in the pre-intervention period.

CONCLUSIONS

A programme to optimize linezolid use can contribute to reducing the resistance rate of CoNS and E. faecalis to this antibiotic.

Emergence of linezolid-resistant coagulase-negative staphylococci in an intensive care unit

BACKGROUND

The aim of this study was to report the emergence of linezolid-resistant coagulase-negative staphylococci (CoNS) in an intensive care unit.

METHODS

An observational study was conducted in critically ill patients with colonization or infection by linezolid-resistant CoNS between January 2010 and December 2014. We analyzed the epidemiological and clinical features, and the mechanism of resistance to linezolid. We also evaluated the association between the incidence of linezolid-resistant CoNS strains and the consumption of linezolid in the study period.

RESULTS

During the study period 49 patients had a linezolid-resistant CoNS strain isolated from clinical samples (blood in 42 cases, urine in 6, peritoneal fluid in 1). Molecular study showed a combination of mechanisms of resistance. Most patients were critically ill (APACHE II score = 21.9 ± 8.3) and nearly all had undergone surgery and invasive procedures, and had prior exposure to antibiotics. Linezolid-resistant CoNS were considered to be contaminants in 42 patients and associated with infection in 7 patients, comprising bacteremia and septic shock in most of them. They were successfully treated with glycopeptides or daptomycin. A modest significant correlation was observed between the decrease in linezolid consumption and the lower incidence of resistant isolates.

CONCLUSIONS

Linezolid-resistant CoNS had emerged in critically ill patients with severe underlying diseases and prior antibiotic exposure. Most isolates represented colonization; however, linezolid-resistant CoNS can produce serious infections in critically ill patients. Glycopeptides and daptomycin seem to provide useful alternatives for therapy of these infections. A relationship was found between linezolid consumption and the incidence of linezolid-resistant CoNS strains.

The prevention and management of infections due to multidrug resistant organisms in haematology patients

Infections due to resistant and multidrug resistant (MDR) organisms in haematology patients and haematopoietic stem cell transplant recipients are an increasingly complex problem of global concern. We outline the burden of illness and epidemiology of resistant organisms such as gram-negative pathogens, vancomycin-resistant Enterococcus faecium (VRE), and Clostridium difficile in haematology cohorts. Intervention strategies aimed at reducing the impact of these organisms are reviewed: infection prevention programmes, screening and fluoroquinolone prophylaxis. The role of newer therapies (e.g. linezolid, daptomycin and tigecycline) for treatment of resistant and MDR organisms in haematology populations is evaluated, in addition to the mobilization of older agents (e.g. colistin, pristinamycin and fosfomycin) and the potential benefit of combination regimens.

The emergence of vancomycin-resistant enterococcal bacteremia in hematopoietic stem cell transplant recipients

Abstract As antimicrobial resistance increases, understanding the current epidemiology of bloodstream infections (BSIs) in hematopoietic stem cell transplant (HSCT) recipients is essential to guide empirical antimicrobial therapy. We therefore reviewed microbial etiologies, timing and outcomes of BSIs in patients who were transplanted from September 2007 to December 2011. Vancomycin-resistant enterococci (VRE) were the most common pathogens in allogeneic HSCT recipients and the fourth most common after autologous transplant. VRE did not cause any of 101 BSIs in neutropenic patients who were not receiving antibacterials, but caused 32 (55%) of 58 BSIs in neutropenic patients receiving a broad-spectrum β-lactam agent (p < 0.001). Rates of septic shock and 7-day mortality were 5% and 0% for streptococcal bacteremia, 12% and 18% for VRE bacteremia, and 20% and 14% for Gram-negative bacteremia. In conclusion, VRE bacteremia was the most common BSI in allogeneic HSCT recipients, occurred primarily in neutropenic patients receiving broad-spectrum β-lactams and was associated with poor outcomes.

Mechanisms of linezolid resistance among Staphylococci in a tertiary hospital

The mechanisms of linezolid resistance among 86 staphylococcal isolates from two intensive care units were investigated. The most frequent was the G2576T mutation in the 23S rRNA (82%). The cfr gene was found in 17% of the isolates, seven S. aureus and eight S. epidermidis isolates. Four of the S. epidermidis isolates had the G2576T mutation and the cfr gene. In four S. haemolyticus isolates, the mechanism could not be identified.