Effectiveness of Fosfomycin for the Treatment of Multidrug-Resistant Escherichia coli Bacteremic Urinary Tract Infections: A Randomized Clinical Trial

Effectiveness and tolerability of intravenous fosfomycin in treating complicated urinary tract infections caused by Escherichia coli: a prospective cohort study from the FOSFOMIC project

OBJECTIVES

The FOSFOMIC study assessed the clinical and microbiological effectiveness, and safety of intravenous fosfomycin in treating complicated urinary tract infections (cUTIs) caused by Escherichia coli, in comparison with other intravenous antimicrobials.

METHODS

A prospective, multinational matched cohorts study involving adults with community-acquired cUTIs and receiving targeted therapy with intravenous fosfomycin or other first-line drugs (beta-lactams or fluoroquinolones) was conducted from November 2019 to May 2023 in ten centres from Spain, Italy, and Türkiye. Matching criteria included type of infection acquisition, Charlson and Pitt scores. Endpoints were clinical and microbiological cure, mortality, recurrence, and adverse effects. Analyses used conditional logistic regression and desirability of outcome ranking (DOOR).

RESULTS

Overall, 155 matched pairs were included. Clinical and microbiological cure rates were 65.2% (101/155; 95% CI, 57.4-72.2) and 63.2% (98/155; 95% CI, 55.4-70.4) with fosfomycin and comparators, respectively (adjusted OR, 1.09; 95% CI, 0.68-1.73; p 0.73). Mortality rates were 1.9% (3/155; 95% CI, 0.7-5.5) and 5.8% (9/155; 95% CI, 3.1-10.7), respectively (p 0.11). Recurrence rates were 14.2% (22/155; 95% CI, 9.6-20.6) in the fosfomycin group vs. 10.3% (16/155; 95% CI, 6.1-16.1) (p 0.39). Severe adverse effects occurred in 1.9% (3/155; 95% CI, 0.7-5.5) of patients treated with fosfomycin vs. 0.6% (1/155; 95% CI, 0.0-3.3) in the control group (p 0.62). Non-severe adverse effects were more frequent with fosfomycin, affecting 23.3% (36/155; 95% CI, 17.0-30.7) compared with 7.7% (12/155; 95% CI, 4.1-13.1) in the control group (adjusted OR, 5.36; 95% CI, 2.04-14.1; p < 0.001). In DOOR analysis, fosfomycin demonstrated comparable effectiveness in treating pyelonephritis (probability of better DOOR, 54.0%; 95% CI, 48.5-59.6) and in comparison with ceftriaxone (50.3%; 95% CI, 44.7-55.8), without evidence of inferiority in bacteraemic urinary tract infections (DOOR, 47.3%; 95% CI, 41.7-52.8).

DISCUSSION

Fosfomycin is a viable option for treating cUTIs caused by E. coli, allowing for diversification in the treatment of these high-incidence infections.

Genetic basis of antibiotic resistance in bovine mastitis and its possible implications for human and ecological health

Bovine mastitis is a mammary gland inflammation that can occur due to infectious pathogens, Staphylococcus aureus and Escherichia coli, which are, respectively, the most prevalent Gram-positive and Gram-negative bacteria associated with this disease. Currently, antibiotic treatment has become more complicated due to the presence of resistant pathogens. This review, therefore, aims to identify the most common resistance genes reported for these strains in the last four years. During the review, it was noted that blaZ, blaSHV, blaTEM, and blaampC are the most reported genes for S. aureus and E. coli, associated with drug inactivation, mainly β-lactamases. They are characterized by generating bacterial resistance to β-lactam antibiotics, the most common treatment in animal and human bacterial treatments (penicillins and cephalosporins, among others). Genes associated with efflux systems were also present in the two strains and included norA, tetA, tetC, and tetK, which generate resistance to macrolide and tetracycline antibiotics. Additionally, the effects of spreading resistance between animals and humans through direct contact (such as consumption of contaminated milk) or indirect contact (through environmental contamination) has been deeply discussed, emphasizing the importance of having adequate sanitation and antibiotic control and administration protocols.

Molecular Pharmacology of the Antibiotic Fosfomycin, an Inhibitor of Peptidoglycan Biosynthesis

The antibiotic fosfomycin is an epoxy-phosphonate natural product with a broad spectrum of antibacterial activity and distinct mechanism of action that has been in clinical use for 50 years. Fosfomycin is an irreversible covalent inhibitor of UDP-GlcNAc enolpyruvyl transferase (MurA), which catalyzes the first committed step in bacterial peptidoglycan biosynthesis. Fosfomycin binds to the active site of MurA in competition with substrate phosphoenolpyruvate (PEP) and undergoes the ring-opening nucleophilic attack of an active-site cysteine. MurA and its related enolpyruvyl transferase, 5-enolpyruvyl-shikimate-3-phosphate (EPSP) synthase (AroA), are the only known enzymes to catalyze the unusual enolpyruvyl transfer from PEP, and each is the target of an important inhibitor. Specifically, MurA is inactivated by fosfomycin, and EPSP synthase (AroA) of the shikimate pathway is the target of the herbicide glyphosate. Commonalities and differences in enzymatic reaction mechanisms of MurA and EPSP synthase provide a molecular rationale for the specificity of their respective inhibitors. With its distinct mode of molecular action and clinical activity against multidrug-resistant bacteria, fosfomycin continues to motivate the discovery and development of novel inhibitors of MurA.

Intravenous Fosfomycin for Difficult-to-Treat Infections: A Real-Life Multicentric Study in Italy

Background: Fosfomycin, an old antibiotic attracting renewed interest, offers a broad spectrum of activity and unique synergy with other agents. While widely used in severe infections, real-world data on intravenous fosfomycin remain limited. Objectives: This study aimed to describe the clinical and microbiological characteristics of patients treated with intravenous fosfomycin and to analyze its administration modalities in a real-world setting. Methods: A multicenter retrospective cohort study was conducted across five Italian hospitals. Adult patients receiving intravenous fosfomycin between January 2020 and December 2023 were included. Results: We enrolled 393 patients. The median age was 69 years, with most patients (45%) admitted to Critical Care Units. Pneumonia (34%), bloodstream infections (22%), and urinary tract infections (21%) were the most common indications. Gram-negative bacteria, particularly E. coli and P. aeruginosa, were the predominant pathogens. Fosfomycin was used as empirical therapy in 55% of cases and was combined with other agents in almost all cases (99%). The most frequent partners were piperacillin/tazobactam (21%) and new beta-lactam/beta-lactamase inhibitor combinations (18%). The median treatment duration was seven days, with most subjects (65%) receiving a fosfomycin dosage regimen of 16 g/day. Minimum inhibitory concentrations (MICs) values for fosfomycin were available for 61 isolates (15%), with 78.7% (48/61) showing MIC ≤ 32 mg/L. C. difficile infection occurred in only 2% of patients. Mortality rates at 30, 60, and 90 days were 21.6%, 26.7%, and 29.3%, respectively. Conclusions: This study provides valuable insights into the real-world use of intravenous fosfomycin.

Genomic epidemiology of antimicrobial resistance determinants in Chinese swine farm Escherichia coli isolates

Introduction

The extensive use of antimicrobials in pig farming has led to a significant emergence of antimicrobial resistance (AMR) among microorganisms. Given China's prominent position as the leading global swine producer, AMR in pig farming has become a focal point of debates. However, limited research has comprehensively assessed the overall status of AMR in Chinese pig farms.

Methods

Samples were collected from 31 provinces in China. E. coli was identified and isolated using McConkey's selective medium and confirmed through PCR amplification. The MIC value was determined by BD Phoenix™ M50 Automated Identification and Susceptibility device. E. coli J53 (sodium azide-resistant) was used as the recipient in conjugation transfer experiment. The phenotypic and genotypic characteristics of the isolates were comprehensively analyzed using whole-genome sequencing.

Results

227 slurry samples were collected from 52 pig farms located across 31 provinces in seven geographical regions of China. 142 non-duplicate strains of E. coli were isolated, and their resistance phenotypes to 28 antimicrobials were systematically evaluated. ST10 and ST641 isolates were widespread sequence types with numerous antimicrobial resistance genes (ARGs) and virulence factor genes, including bla NDM-1, mcr-1.1, and bla OXA-10, among others. Multiple ARGs were co-located on a single plasmid, and an analysis of the genetic context revealed insertion sequences adjacent to ARGs containing various mobile genetic elements. Conjugation experiments provided additional evidence for the horizontal dissemination of these ARGs.

Discussion

The release of E. coli into the environment via farm slurry comprises a significant emerging contaminant and a potential hazard to public health. Consequently, there is an urgent need to establish universally recognized farm effluent standards for monitoring the dissemination of resistant bacteria and ARGs in China's pig farms.

The pharmacodynamics of fosfomycin in combination with meropenem against Klebsiella pneumoniae studied in an in vitro model of infection

BACKGROUND

Intravenous fosfomycin is used in combination with other antimicrobials for the management of severe and/or multidrug resistant Gram-negative infection. We used an in vitro pharmacokinetic model to study the combination of fosfomycin plus meropenem.

METHODS

Six Klebsiella pneumoniae fosfomycin MICs 8-1024 mg/L, meropenem MICs 0.06->1024 mg/L were employed. A dilutional pharmacokinetic model was used to generate fosfomycin exposure ranges up to a fAUC/MIC 500. Exposure-ranging experiments were repeated in the presence of meropenem at exposures associated with 2 g 8-hourly human dosing for strains with meropenem MICs ≥32 mg/L and at half the bacteriostatic fT > MIC for strains with MICs <32 mg/L. The log change in bacterial burden from the initial inoculum after 24 h drug exposure was taken as the primary endpoint and fAUC/MIC ratios for antibacterial effects were calculated. The risk of emergence of resistance was assessed by measurement of the population profiles.

RESULTS

Fosfomycin fAUC/MIC for bacteriostatic effect at 24 h were >500 for 5/6 K. pneumoniae strains. Meropenem fT > MIC for static effect were 16.6%-77.9% for the strains with meropenem MIC ≤ 64 mg/L. Strains with MICs of >1024 mg/L were not tested. Fosfomycin fAUC/MICs in the presence of meropenem were all reduced and for 5/6 strains the fAUC/MIC for static effect was <10 and <30 for a 2 log drop. Addition of meropenem suppressed changes in fosfomycin population profiles. There were no changes in meropenem population profiles exposed to the combination.

CONCLUSION

Addition of meropenem to fosfomycin had a dramatic impact on the fosfomycin fAUC/MIC exposures required for bacteriostatic and bactericidal effects and suppressed emergence of fosfomycin resistance.

Real-World Use, Effectiveness, and Safety of Intravenous Fosfomycin: The FORTRESS Study

INTRODUCTION

Intravenous fosfomycin (FOS) is a broad-spectrum antibiotic primarily used in combination therapy to treat severe infections caused by both Gram-positive (GP) and Gram-negative (GN) pathogens, including multi-drug resistant (MDR) bacteria. The aim of this study, the largest to date, was to evaluate the effectiveness, safety, usage patterns, and patient characteristics of FOS in a real-world setting.

METHODS

Interim analysis of an ongoing, prospective, non-interventional, multicentre study in five European countries, involving centres in Germany, Italy, the United Kingdom, Greece, and Austria.

RESULTS

A total of 716 patients were enrolled between January 2017 and November 2023 (mean age: 62.8 years, APACHE II: 18.3, SOFA: 6.7). Main indications for FOS were bacteraemia/sepsis (23.6%), complicated urinary tract infections (18.0%), and bone and joint infections (17.4%). Other indications included hospital-acquired/ventilator-associated pneumonia (11.0%), complicated skin and soft tissue infections (9.1%), bacterial meningitis/central nervous system (CNS) infections (7.8%), and infective endocarditis (6.4%). Most common pathogens identified were Staphylococcus aureus (31.4%, including methicillin-resistant S. aureus), Klebsiella spp. (including K. pneumoniae) (17.2%), Escherichia coli (14.2%), coagulase-negative staphylococci (12.9%), other Enterobacterales (10.9%), and Pseudomonas aeruginosa (8.4%). In 34.6% of patients, an MDR pathogen was involved. Carbapenem resistance (CR) was high in Klebsiella spp. infections (59/123, 48.0%). In most patients, FOS was used in combination therapy (90.2%). The median dose was 15 g/day. Overall, clinical success and clinical response were favourable with 75.3% and 83.4% at the end of FOS treatment. Clinical success rates in infections caused by MDR or CR pathogens were 78.0% and 81.8%, respectively. Microbiological cure was achieved in 82.4% of all patients. Electrolyte imbalances were the most frequently observed adverse drug reactions, while gastrointestinal disorders were rare.

CONCLUSION

The results from this study suggest that FOS is a safe and effective option as combination partner in the treatment of patients with severe infections caused by both GP and GN pathogens, including deep-seated infections and/or involvement of MDR bacteria.

TRIAL REGISTRATION

ClinicalTrials.gov identifier, NCT02979951.

Antimicrobial susceptibilities of clinical bacterial isolates from urinary tract infections to fosfomycin and comparator antibiotics determined by agar dilution method and automated micro broth dilution

Uncomplicated bacteremic urinary tract infections (bUTIs) are common, often caused by Escherichia coli, Klebsiella pneumoniae, and Enterococcus faecalis, with most encounters treated empirically. As rates of antimicrobial resistance increase, available antibiotic treatment options are dwindling. Novel antibiotics approved for treating bUTIs are limited, leading to a resurgence of interest in older antibiotics, including fosfomycin. Here, clinical urine samples from patients including military personnel, retirees, and their dependents diagnosed with bUTIs from a military hospital located in Bethesda, Maryland, were tested for susceptibility to fosfomycin and comparator antibiotics (levofloxacin, nitrofurantoin, and trimethoprim-sulfamethoxazole [TMS]). A total of 1,353 nonduplicate bacterial isolates were tested, including 605 non-ESBL and 285 ESBL E. coli, and 84 non-ESBL and 52 ESBL K. pneumoniae. Fosfomycin susceptibility rates were similar for non-ESBL and ESBL E. coli (95.9% vs 96.1%) and K. pneumoniae (38.1% vs 36.5%). Fosfomycin demonstrated high activity against other Enterobacterales and gram-positive organisms including Enterobacter faecalis and Staphylococcus aureus. Interestingly, most fosfomycin non-susceptible isolates were susceptible to other first-line bUTI treatment options, and most isolates that were non-susceptible to other first-line bUTI treatment option were susceptible to fosfomycin. ESBL K. pneumoniae isolates were the least susceptible to current first-line treatment options. Fosfomycin Etest demonstrated high sensitivity compared to agar dilution, making it a viable AST testing method especially in resource-limited areas. Overall, we demonstrated fosfomycin has high activity against common etiologies that cause bUTIs. Further clinical efficacy studies investigating the use of fosfomycin in treating non-E. coli bUTI pathogens, as single or combination therapy, are warranted.

IMPORTANCE

Uncomplicated bUTIs are often caused by Escherichia coli, Klebsiella pneumoniae, and Enterococcus faecalis. Fosfomycin is one of the recommended firstline antibiotics for the treatment of symptomatic, uncomplicated bUTIs. Fosfomycin susceptibility testing is complicated by the fact that although both CLSI and EUCAST recognize agar dilution (AD) as the reference method albeit being labor-intensive, breakpoints are different, and Etest is only approved by EUCAST. We investigated the susceptibility of bUTI clinical isolates to fosfomycin using AD and compared performance in a subset of isolates to Etest. Fosfomycin susceptibility profiles of bacterial isolates were compared to other firstline antibiotics. We found isolates were susceptible to fosfomycin at similar or higher rates compared to other firstline antibiotics. Importantly, fosfomycin was effective against isolates producing extended-spectrum beta-lactamases and those that were resistant to other firstline treatments. Furthermore, our data showed Etest was a viable option for susceptibility testing with 94% agreement to the AD.

Fosfomycin in bacteraemic urinary tract infection due to multidrug-resistant Escherichia coli: insights of post hoc DOOR analysis of the FOREST trial

PURPOSE

A post hoc analysis of data from a previously published clinical trial was conducted using the desirability of outcome ranking (DOOR) methodology with the aim provide additional information on the use of fosfomycin for the treatment of bacteraemic urinary tract infection (BUTI) caused by multi-drug-resistant (MDR) E. coli.

METHODS

Three DOOR systems with five, six and seven categories, respectively were developed. Safety and efficacy were prioritised in all rankings, but step down to oral therapy and exposure to antibiotics with lower ecological impact were also considered in DOOR-6 and DOOR-7. The probability that a patients assigned to fosfomycin was classified into a more desirable outcome category was calculated for the three DOOR definitions. Subgroups analyses and an ordinal logistic regression model were also performed.

RESULTS

Data from 143 participants were analysed. The probability of having a more desirable outcome after treatment with fosfomycin versus the comparators was 0.44 (95% CI 0.36 - 0.52) for DOOR-5; 0.50 (95% IC 0.42 - 0.58) using DOOR-6 and 0.61 (95% CI 0.53-0.69) with DOOR-7. In subgroups, the highest probability of having a better DOOR with fosfomycin was seen in the clinically evaluable population and among patients without chronic heart disease or renal insufficiency for the DOOR-7 definition.

CONCLUSIONS

DOOR analysis could be applied to the FOREST trial data; the results were somehow different for the different DOOR systems used. Overall, fosfomycin was favoured when oral step-down treatment and use of antibiotics with lower ecological impact were included.

Drug susceptibility of uropathogens isolated from patients treated at the Mazovian Specialized Hospital in Radom

Urinary tract infections (UTI) are a significant problem among populations worldwide. It is mainly associated with the increasing incidence of recurrence, complications and the increasing drug resistance of uropathogens. The aim of this study was to demonstrate the prevalence of resistance among pathogens causing urinary tract infections. The material for the study was data obtained from the Mazovian Specialized Hospital (M.S.H) in Radom over a period of 2 years. Urine was collected from hospitalized patients with UTI. Statistical calculations were performed using statistical software. During the study period, 3,917 patients underwent microbiological examination of urine, and almost 15% of them were found to be infected with UTI. Based on statistical analysis of drug susceptibility of the most common uropathogens, it was shown that urinary tract infections caused by Escherichia coli or Klebsiella pneumoniae, among others, often show high resistance to fluoroquinolones and β-lactam antibiotics. Proteus mirabilis strains have been shown to be more resistant to aminoglycosides and fluoroquinolones than to beta-lactams. In the case of Pseudomonas aeruginisa, resistance to fluoroquinolones predominates. On the other hand, UTI caused by Acientobacter baumannii should be treated based on the results of drug susceptibility testing due to the increasing prevalence of multidrug-resistant strains.

Effect of Inadequate Treatment in Adult Patients with Community-Acquired Acute Pyelonephritis Due to Enterobacterales Under Empirical Management with Cefazolin

Background/Objectives: First-generation cephalosporins are used in some countries, primarily in Latin America and other low-resource regions, as a first-line or alternative empirical treatment for patients with acute pyelonephritis (AP). This study aimed to evaluate the impact of inappropriate empirical therapy with cefazolin on the clinical outcomes of adult patients with community-acquired AP caused by resistant Enterobacterales, requiring hospitalization in two tertiary hospitals in Bogotá. Methods: This retrospective cohort study included hospitalized patients with community-acquired AP caused by Enterobacterales who received initial treatment with cefazolin at two tertiary-level institutions in Colombia (January 2013-2020). Inappropriate treatment was defined as a resistant isolate to cefazolin in the urine culture. Outcomes assessed included hospital stay, hospital mortality, and recurrence. Results: A total of 1031 patients were admitted, among whom 218 (21.1%) received inappropriate treatment. The mean length of stay was 4.8 (5.1) days, 996 (96.6%) survived to discharge, and 113 (11.0%) were admitted for a recurrence of AP. Inappropriate treatment had no impact on hospital stay (RRA 0.98, 95% CI 0.84-1.15) or hospital mortality (OR 1.02, 95% CI 0.47-2.19), although it was associated with a greater risk of admission because of recurrence (OR 3.7, 95% CI 2.4-5.8). Conclusions: We found that inadequate empirical treatment with cefazolin in adult patients with community-acquired acute pyelonephritis does not appear to change the length of hospital stay or in-hospital mortality in patients but is associated with an increased risk of readmission due to recurrence; this might favor the use of empirical narrow-spectrum antibiotics but with strategies that allow monitoring or early detection of microbiological non-eradication to prevent recurrence.

Could a Reduced Dose of 8 g of Continuous Infusion Fosfomycin Be Considered as Effective as and Safer than a Standard 16 g Dose When Combined with High-Dose Daptomycin in the Treatment of Staphylococcal osteoarticular Infections?

Background: Daptomycin plus fosfomycin combination therapy is a valuable strategy for treating staphylococcal osteoarticular infections (OIs), but hypernatremia and hypokalemia due to sodium overload are important issues. The aim of this study was to assess the likelihood of attaining a pharmacokinetic/pharmacodynamic (PK/PD) target of AUC/MIC > 66.6 and/or of 70%t > MIC with continuous infusion (CI) fosfomycin at the recommended vs. reduced dose in patients with OIs receiving combination therapy with high-dose daptomycin. Adverse events were also evaluated. Methods: Patients with OIs treated with 8-10 mg/kg daily daptomycin plus CI fosfomycin, and who had a ≥1 TDM assessment of CI fosfomycin, were retrospectively included in the high-dose (16 g daily) or reduced-dose (<16 g daily) groups. The attainment of the PK/PD targets of 70%t > MIC and AUC/MIC > 66.6 up to an MIC of 32 mg/L was calculated. A CART analysis was used to identify a cut-off of fosfomycin AUC that indicated occurrence of hypernatremia and/or hypokalemia. Results: A total of 44 and 39 patients were included in the high- and reduced-dose groups, respectively. The two groups did not differ in terms of demographic characteristics, underlying infectious diseases and microbiological isolates. No differences between groups in attaining both PK/PD targets up to an MIC of 32 mg/L and in C-reactive protein reduction at the end of treatment were observed. Fosfomycin AUC > 8245 mg × h/L and >8326 mg × h/L were associated with hypernatremia and hypokalemia, respectively. Conclusions: CI fosfomycin at 8 g daily may reach optimal PK/PD target attainment with better safety than the recommended 16 g daily dose in patients with preserved renal function. Targeting fosfomycin AUC at 2131-8326 mg × h/L or steady-state concentration at 88.8-347 mg/L may be adequate for optimizing drug pharmacodynamics up to an MIC of 32 mg/L and minimizing the risk of hypernatremia and hypokalemia.

Multidrug-resistant Gram-negative bacterial infections

Multidrug-resistant Gram-negative bacterial infections cause significant morbidity and mortality globally. These pathogens easily acquire antimicrobial resistance (AMR), further highlighting their clinical significance. Third-generation cephalosporin-resistant and carbapenem-resistant Enterobacterales (eg, Escherichia coli and Klebsiella spp), multidrug-resistant Pseudomonas aeruginosa, and carbapenem-resistant Acinetobacter baumannii are the most problematic and have been identified as priority pathogens. In response, several new diagnostic technologies aimed at rapidly detecting AMR have been developed, including biochemical, molecular, genomic, and proteomic techniques. The last decade has also seen the licensing of multiple antibiotics that have changed the treatment landscape for these challenging infections.

Efficacy of carbapenems and alternative antimicrobials for treating complicated urinary tract infections caused by third-generation cephalosporin-resistant gram-negative bacteria: A systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Specific data concerning the efficacy of alternative antibiotics for carbapenems against complicated urinary tract infections (cUTIs) attributed to antimicrobial-resistant (AMR) uropathogens are lacking.

OBJECTIVES

This study aimed to assess the efficacy of carbapenems and non-carbapenem antibiotics in the clinical outcomes of cUTIs caused by AMR uropathogens.

METHODS

In this systematic review and meta-analysis, databases, including MEDLINE/PubMed, the Cochrane Library, Embase and ClinicalTrials.gov, were searched. The study eligibility criteria were research articles conducted as randomised controlled trials that evaluated the composite outcomes of cUTIs. Participants were adult patients with cUTIs caused by gram-negative uropathogens resistant to third-generation cephalosporins. The intervention involved a non-carbapenem class of antimicrobial agents with in vitro activities against gram-negative uropathogens resistant to third-generation cephalosporins. Two independent researchers assessed the risk-of-bias using the second version of the Cochrane risk-of-bias tool for randomised trials. The treatment effects on each outcome were estimated as a risk ratio (RR) with a 95 % confidence interval (CI) using the random-effects model. Heterogeneity was assessed using the Cochrane Q-test and I2 statistics.

RESULTS

Through database searches, 955 articles were retrieved. After screening the titles and abstracts, 52 articles were screened in full text. Finally, 12 studies met the inclusion criteria. No significant differences in efficacy were observed between alternative antibiotics and carbapenems (composite outcome, RR, 0.96; 95 % CI, 0.63-1.49; I2 = 21 %; low certainty of evidence).

CONCLUSIONS

Alternative antibiotics had clinical efficacy similar to that of carbapenems for treating patients with cUTI caused by gram-negative uropathogens resistant to third-generation cephalosporins.

Combination therapy with IV fosfomycin for adult patients with serious Gram-negative infections: a review of the literature

Treatment of patients with serious infections due to resistant Gram-negative bacteria remains highly problematic and has prompted clinicians to use existing antimicrobial agents in innovative ways. One approach gaining increased therapeutic use is combination therapy with IV fosfomycin. This article reviews the preclinical pharmacokinetic/pharmacodynamic (PK/PD) infection model and clinical data surrounding the use of combination therapy with IV fosfomycin for the treatment of serious infections caused by resistant Gram-negative bacteria. Data from dynamic in vitro and animal infection model studies of highly resistant Enterobacterales and non-lactose fermenters are positive and suggest IV fosfomycin in combination with a β-lactam, polymyxin or aminoglycoside produces a synergistic effect that rivals or surpasses that of other aminoglycoside- or polymyxin-containing regimens. Clinical studies performed to date primarily have involved patients with pneumonia and/or bacteraemia due to Klebsiella pneumoniae, Pseudomonas aeruginosa or Acinetobacter baumannii. Overall, the observed success rates with fosfomycin combination regimens were consistent with those reported for other combination regimens commonly used to treat these patients. In studies in which direct treatment comparisons can be derived, the results suggest that patients who received fosfomycin combination therapy had similar or improved outcomes compared with other therapies and combinations, especially when it was used in combination with a β-lactam that (1) targets PBP-3 and (2) has exceptional stability in the presence of β-lactamases. Collectively, the data indicate that combination therapy with IV fosfomycin should be considered as a potential alternative to aminoglycoside or polymyxin combinations for patients with antibiotic-resistant Gram-negative infections when benefits outweigh risks.

Individual health insurance data of antibiotic delivery in previous months as a tool to predict bacterial resistance of urinary tract infection: A prospective cohort study

OBJECTIVES

We aimed to quantify the individual risk of antimicrobial resistance among patients with community-acquired Escherichia coli urinary tract infection (UTI) according to their antibiotic exposure over the previous 18 months.

PATIENTS AND METHODS

French patients were prospectively recruited in two centers in 2015-2017. Resistance of isolates to amoxicillin (AMX), amoxicillin-clavulanate (AMC), third-generation cephalosporins (3GC), trimethoprim-sulfamethoxazole (TMP-SMX), fluoroquinolones (FQ) and fosfomycin (FOS) was analysed according to previous intra-class and inter-class antibiotic exposure documented in health insurance files.

RESULTS

Previous antibiotic exposure was found in 588 (81.4 %) of the 722 UTI cases analysed (564 patients). Recent exposure (three months before UTI) was associated with stronger intra-class impact on E. coli resistance compared to remote exposure (18 months before UTI) for AMX, AMC, FQ and TMP-SMX, with respective adjusted odds ratios [95 % confidence interval] of 1.63 [1.20-2.21], 1.59 [1.02-2.48], 3.01 [1.90-4.77], and 2.60 [1.75-3.87]. AMX, FQ, and TMP-SMX also showed significant inter-class impact. Resistance to 3GC was not significantly associated with intraclass exposure (adjusted OR: 0.88 [0.41-1.90]). FOS resistance was remarkably low (0.4 %). Duration of the antibiotic-free period required for resistance risk to drop below 10 %, the threshold for empirical use in UTI, was modelled as < 1 month for 3GC, >18 months for AMX and TMP-SMX and uncertain for AMC (5.2 months [2.3 to > 18]) and FQ (17.4 months [7.4 to > 18]).

CONCLUSIONS

Resistance of E. coli causing UTI is partially predicted by previous personal antibiotic delivery.

Intravenous Fosfomycin as Adjunctive Therapy for Gram-Negative Bacteria Bloodstream Infections: A Propensity Score Adjusted Retrospective Cohort Study

BACKGROUND

The role of intravenous fosfomycin (iv-FOS) as a part of combination therapy for Gram-negative bacteria bloodstream infections (GNB-BSI) needs to be evaluated in clinical practice, as in vitro data show potential efficacy.

METHODS

All consecutive patients with a GNB-BSI from 01 January 2021 to 01 April 2023 were included. Primary outcome was 30-day mortality. A Cox regression analysis was used to identify predictors of mortality; an inverse-probability of treatment-weighting (IPTW) analysis was also performed.

RESULTS

Overall, 363 patients were enrolled: 211 (58%) males, with a median (q1-q3) age of 68 (57-78) years, and a median Charlson comorbidity index of 5 (3-7). At GNB-BSI onset, the median SOFA score was 5 (2-7) and 122 patients (34%) presented with septic shock. Pathogens were principally Klebsiella pneumoniae (42%), Escherichia coli (28%) and Pseudomonas aeruginosa (17%); of them, 36% were carbapenem-resistant. The therapy included carbapenems (40%), cephalosporins (37%) and beta-lactams/beta-lactamases-inhibitors (19%); a combination with iv-FOS was used in 98 (27%) cases at a median dosage of 16 (16-18) g/daily. The use of iv-FOS was not associated with reduced crude mortality (21% vs 29%, P = 0.147). However, on multivariable Cox-regression, combination therapy with iv-FOS resulted in protection for mortality (aHR 0.51, 95% CI 0.28-0.92), but not other combo-therapies (HR 0.69, 95% CI 0.44-1.16). This result was also confirmed with the IPTW-adjusted Cox model (aHR 0.52, 95% CI 0.31-0.91). Subgroup analysis suggested a benefit in severe infections (SOFA > 6, PITT ≥ 4) and when iv-FOS was initiated within 24 hours of GNB-BSI onset.

CONCLUSIONS

Fosfomycin in combination therapy for GNB-BSI may have a role in improving survival. These results justify the development of further clinical trials.

Guidelines for Antibiotics Prescription in Critically Ill Patients

How to cite this article: Khilnani GC, Tiwari P, Mittal S, Kulkarni AP, Chaudhry D, Zirpe KG, et al. Guidelines for Antibiotics Prescription in Critically Ill Patients. Indian J Crit Care Med 2024;28(S2):S104-S216.

Adverse events during intravenous fosfomycin therapy in a real-life scenario. Risk factors and the potential role of therapeutic drug monitoring

BACKGROUND

Intravenous fosfomycin (IVFOF) is gaining interest in severe infections. Its use may be limited by adverse events (AEs). Little experience exists on IVFOF therapeutic drug monitoring (TDM) in real-life setting.

PATIENTS AND METHODS

Retrospective study of patients receiving IVFOF for > 48 h at Policlinico Hospital (Milan, Italy) from 01/01/2019 to 01/01/2023. AEs associated to IVFOF graded CTCAE ≥ II were considered. Demographic and clinical risk factors for IVFOF-related AEs were analysed with simple and multivariable regression models. The determination of IVFOF TDM was made by a rapid ultraperformance liquid chromatography mass spectrometry method (LC-MS/MS) on plasma samples. The performance of TDM (trough levels (Cmin) in intermittent infusion, steady state levels (Css) in continuous infusion) in predicting AEs ≤ 5 days after its assessment was evaluated.

RESULTS

Two hundred and twenty-four patients were included. At IVFOF initiation, 81/224 (36.2%) patients were in ICU and 35/224 (15.7%) had septic shock. The most frequent infection site was the low respiratory tract (124/224, 55.4%). Ninety-five patients (42.4%) experienced ≥ 1AEs, with median time of 4.0 (2.0-7.0) days from IVFOF initiation. Hypernatremia was the most frequent AE (53/224, 23.7%). Therapy discontinuation due to AEs occurred in 38/224 (17.0%). ICU setting, low respiratory tract infections and septic shock resulted associated with AEs (RRadjusted 1.59 (95%CI:1.09-2.31), 1.46 (95%CI:1.03-2.07) and 1.73 (95%CI:1.27-2.37), respectively), while IVFOF daily dose did not. Of the 68 patients undergone IVFOF TDM, TDM values predicted overall AEs and hypernatremia with AUROC of 0.65 (95%CI:0.44-0.86) and 0.91 (95%CI:0.79-1.0) respectively for Cmin, 0.67 (95%CI:0.39-0.95) and 0.76 (95%CI:0.52-1.0) respectively for Css.

CONCLUSIONS

We provided real world data on the use of IVFOF-based regimens and associated AEs. IVFOF TDM deserves further research as it may represent a valid tool to predict AEs.

KEY POINTS

Real world data on intravenous fosfomycin for severe bacterial infections. AEs occurred in over 40% (therapy discontinuation in 17%) and were related to baseline clinical severity but not to fosfomycin dose. TDM showed promising results in predicting AEs.

Population pharmacokinetic/pharmacodynamic target attainment analysis of IV fosfomycin for the treatment of MDR Gram-negative bacterial infections

BACKGROUND

IV fosfomycin is used against MDR Gram-negative bacilli (GNB) but has dose-limiting side effects, especially in patients with impaired kidney function.

OBJECTIVES

To determine the optimal dosage of IV fosfomycin for patients with varying degrees of kidney function.

METHODS

Adult patients receiving IV fosfomycin for treatment of GNB were eligible. Five serial blood samples were collected after at least three doses of fosfomycin; plasma was assayed by LC-MS/MS and modelled by population pharmacokinetic analysis. The PTA for AUC24/MIC of 98.9 for Escherichia coli and Klebsiella pneumoniae, and 40.8 for Pseudomonas aeruginosa were computed by Monte Carlo simulations. Cumulative fractions of response (CFR) were analysed for each pathogen using EUCAST MIC distributions.

RESULTS

A total of 24 patients were included. Creatinine clearance (CLCR) and gender significantly influenced fosfomycin clearance. The kidney function-adjusted dosing regimens are proposed by using the lowest dose that can achieve ≥90% PTA for AUC24/MIC of 98.9 at an MIC of ≤32 mg/L (EUCAST v.13 susceptibility breakpoint for Enterobacterales). For patients with normal kidney function (CLCR 91-120 mL/min), a dosage of 15 g/day is suggested. This regimen achieved 97.1% CFR against E. coli, whereas CFR was 72.9% for K. pneumoniae and 76.7% for P. aeruginosa.

CONCLUSIONS

A fosfomycin dosage of 15 g/day with adjustment according to kidney function provided high PTA and CFR when treating E. coli. This dosage is lower than that used in current practice and may improve tolerability. Higher dosages may be needed for P. aeruginosa; however, safety data are limited.

Characterizing carbapenemase-producing Escherichia coli isolates from Spain: high genetic heterogeneity and wide geographical spread

Introduction

Carbapenemase-Producing Escherichia coli (CP-Eco) isolates, though less prevalent than other CP-Enterobacterales, have the capacity to rapidly disseminate antibiotic resistance genes (ARGs) and cause serious difficult-to-treat infections. The aim of this study is phenotypically and genotypically characterizing CP-Eco isolates collected from Spain to better understand their resistance mechanisms and population structure.

Methods

Ninety representative isolates received from 2015 to 2020 from 25 provinces and 59 hospitals Spanish hospitals were included. Antibiotic susceptibility was determined according to EUCAST guidelines and whole-genome sequencing was performed. Antibiotic resistance and virulence-associated genes, phylogeny and population structure, and carbapenemase genes-carrying plasmids were analyzed.

Results and discussion

The 90 CP-Eco isolates were highly polyclonal, where the most prevalent was ST131, detected in 14 (15.6%) of the isolates. The carbapenemase genes detected were bla OXA-48 (45.6%), bla VIM-1 (23.3%), bla NDM-1 (7.8%), bla KPC-3 (6.7%), and bla NDM-5 (6.7%). Forty (44.4%) were resistant to 6 or more antibiotic groups and the most active antibiotics were colistin (98.9%), plazomicin (92.2%) and cefiderocol (92.2%). Four of the seven cefiderocol-resistant isolates belonged to ST167 and six harbored bla NDM. Five of the plazomicin-resistant isolates harbored rmt. IncL plasmids were the most frequent (45.7%) and eight of these harbored bla VIM-1. bla OXA-48 was found in IncF plasmids in eight isolates. Metallo-β-lactamases were more frequent in isolates with resistance to six or more antibiotic groups, with their genes often present on the same plasmid/integron. ST131 isolates were associated with sat and pap virulence genes. This study highlights the genetic versatility of CP-Eco and its potential to disseminate ARGs and cause community and nosocomial infections.

Longitudinal analysis within one hospital in sub-Saharan Africa over 20 years reveals repeated replacements of dominant clones of Klebsiella pneumoniae and stresses the importance to include temporal patterns for vaccine design considerations

BACKGROUND

Infections caused by multidrug-resistant gram-negative bacteria present a severe threat to global public health. The WHO defines drug-resistant Klebsiella pneumoniae as a priority pathogen for which alternative treatments are needed given the limited treatment options and the rapid acquisition of novel resistance mechanisms by this species. Longitudinal descriptions of genomic epidemiology of Klebsiella pneumoniae can inform management strategies but data from sub-Saharan Africa are lacking.

METHODS

We present a longitudinal analysis of all invasive K. pneumoniae isolates from a single hospital in Blantyre, Malawi, southern Africa, from 1998 to 2020, combining clinical data with genome sequence analysis of the isolates.

RESULTS

We show that after a dramatic increase in the number of infections from 2016 K. pneumoniae becomes hyperendemic, driven by an increase in neonatal infections. Genomic data show repeated waves of clonal expansion of different, often ward-restricted, lineages, suggestive of hospital-associated transmission. We describe temporal trends in resistance and surface antigens, of relevance for vaccine development.

CONCLUSIONS

Our data highlight a clear need for new interventions to prevent rather than treat K. pneumoniae infections in our setting. Whilst one option may be a vaccine, the majority of cases could be avoided by an increased focus on and investment in infection prevention and control measures, which would reduce all healthcare-associated infections and not just one.

Intravenous fosfomycin in combination regimens as a treatment option for difficult-to-treat infections due to multi-drug-resistant Gram-negative organisms: A real-life experience

AIM

To investigate the efficacy of intravenous (IV) fosfomycin as combination therapy for treatment of difficult-to-treat (DTT) acute and subacute infections with multi-drug-resistant (MDR) Gram-negative bacteria (GNB), and risk factors associated with 90-day mortality.

METHODS

A retrospective, observational, monocentric study enrolled patients treated with IV fosfomycin in combination regimens (≥72 h) for proven DTT-MDR-GNB infection. Multi-variate regression analysis identified independent risk factors for 90-day mortality. A propensity score for receiving fosfomycin was performed to control for confounding factors.

RESULTS

In total, 70 patients were included in this study: 54.3% had carbapenem-resistant isolates, 31.4% had ceftazidime/avibactam-resistant isolates and 28.6% had ceftolozane/tazobactam-resistant isolates. The main pathogens were Pseudomonas aeruginosa (57.1%) and Klebsiella pneumoniae (22.9%). The most prevalent infections were nosocomial pneumonia (42.9%), osteomyelitis (17.1%) and intra-abdominal infections. All-cause 30- and 90-day mortality were 15.7% and 31.4%, respectively (18.9% and 50% considering acute DTT-MDR-GNB infections alone). Relapse at 30 days occurred in 22.9% of cases (29% with emergence of fosfomycin resistance). Mortality at 90 days was independently associated with septic shock and ceftolozane/tazobactam resistance. The relationship between resistance to ceftolozane/tazobactam and 90-day mortality was confirmed to be significant after adjustment by propensity score analysis (hazard ratio 5.84, 95% confidence interval 1.65-20.68; P=0.006).

CONCLUSIONS

Fosfomycin seems to be a promising salvage, combination treatment in DTT-MDR-GNB infections. Resistance to ceftolozane/tazobactam seems to be independently associated with treatment failure. Randomized clinical trials focusing on pathogen and infection sites are needed urgently to demonstrate the superiority of fosfomycin in combination with other agents for the resolution of DTT-MDR-GNB infections.

Pharmacokinetics/pharmacodynamics cut-off determination for fosfomycin using Monte Carlo simulation in healthy horses

Fosfomycin (FOM) is an approved veterinary medicinal product for large animals in Japan, but Clinical breakpoint (CBP) for antimicrobial susceptibility test (AST) is not defined for animals. This study aimed at conducting a pharmacokinetics/pharmacodynamics (PK/PD) analysis to determine the PK/PD cutoff for the CBP in horses. Drug concentrations following single intravenous administration (IV) of 20 mg/kg body weight (BW) FOM in nine horses were measured using liquid chromatography/mass spectrometry. The data were modelled using a nonlinear mixed-effects model, followed by Monte Carlo simulations. A 90% probability of target attainment for a PK/PD target of the ratio of Area Under the free plasma concentration-time curve divided by the minimal inhibitory concentration (MIC) >24 hr was set as PK/PD cut-off. The PK/PD cutoff for FOM 20 mg/kg BW q12 hr IV was estimated with the MIC value of ≤16.0 mg/L, and this regimen was considered effective against E. coli (MIC90; 16.0 mg/L) in healthy horses based on the MIC90 values of the wild population. Owing to the relevance of FOM to human health, veterinarians should use q 12 hr FOM 20 mg /kg against E. coli infections with an MIC <16 µg/mL, as suggested by our PK/PD cutoff after AST.

Comparison of three doses of amikacin on alternate days with a daily dose of meropenem during the same period for the treatment of urinary tract infection with E. coli: a double-blind clinical trial

OBJECTIVES

Urinary tract infections (UTIs) are very common infections in humans, and Escherichia coli (E. coli) is the commonest pathogen leading to UTIs. The generation of beta-lactamase enzymes in this bacterium results in its resistance against many antibiotics. This study compares three doses of amikacin on alternate days with a daily dose of meropenem in the same period for the treatment of UTIs with E. coli in a double-blind clinical trial.

METHODS

The current double-blind clinical trial compares three doses of amikacin on alternate days with a daily dose of meropenem in the same period for the treatment of UTIs with E. coli. The patients were assigned to two groups: Intervention (receiving a single dose of amikacin once a day at 48-h intervals for a week, three doses) and control (receiving meropenem for 1/TDS for a week).

RESULTS

The E. coli infection frequency was 61 (21 cases of non-ESBL and 40 cases of ESBL-positive infections) and the frequency of the other infections was 52 (46%). In the patients with ESBL E. coli infection, ciprofloxacin (21; 70%) showed the highest antibiotic resistance, and nitrofurantoin (33; 91.7%) showed the highest sensitivity. The baseline variables between the control and intervention groups indicated no significant difference (p > 0.05). The frequency of signs and symptoms showed no significant difference between the amikacin and meropenem groups in the first 24 h and the first week. In the second week of follow-up, no clinical signs or symptoms were observed in the two groups.

CONCLUSION

The results of this study showed that treatment with amikacin, 1 g q48h, for one week (three doses) has the same result as meropenem, 1 g q8h, for one week (21 doses). The results are the same for the treatment of UTIs with ESBL positive and ESBL negative. Amikacin can be used once every 48 h to treat UTIs, is less expensive and can be administered on an outpatient basis.

TRIAL REGISTRATION

This study was registered in the Iranian Registry of Clinical Trials (IRCT) with ID number: IRCT20170417033483N2 on the date 2018-02-13.

New Antimicrobials and New Therapy Strategies for Endocarditis: Weapons That Should Be Defended

The overall low-quality evidence concerning the clinical benefits of different antibiotic regimens for the treatment of infective endocarditis (IE), which has made it difficult to strongly support or reject any regimen of antibiotic therapy, has led to a discrepancy between the available guidelines and clinical practice. In this complex scenario, very recently published guidelines have attempted to fill this gap. Indeed, in recent years several antimicrobials have entered the market, including ceftobiprole, ceftaroline, and the long-acting lipoglycopeptides dalbavancin and oritavancin. Despite being approved for different indications, real-world data on their use for the treatment of IE, alone or in combination, has accumulated over time. Furthermore, an old antibiotic, fosfomycin, has gained renewed interest for the treatment of complicated infections such as IE. In this narrative review, we focused on new antimicrobials and therapeutic strategies that we believe may provide important contributions to the advancement of Gram-positive IE treatment, providing a summary of the current in vitro, in vivo, and clinical evidence supporting their use in clinical practice.

Carbapenem resistant Enterobacterales in the United Arab Emirates: a retrospective analysis from 2010 to 2021

BACKGROUND

Carbapenem-resistant Enterobacterales (CRE) are spreading in the United Arab Emirates (UAE) where their dissemination is facilitated by international travel, trade, and tourism. The objective of this study is to describe the longitudinal changes of CRE as reported by the national AMR surveillance system of the UAE.

METHODS

In this study, we retrospectively describe CRE isolated from 317 surveillance sites, including 87 hospitals and 230 centers/clinics from 2010 to 2021. The associated clinical, demographic, and microbiological characteristics are presented by relying on the UAE national AMR surveillance program. Data was analyzed using WHONET microbiology laboratory database software (http://www.whonet.org).

RESULTS

A total of 14,593 carbapenem resistant Enterobacterales were analyzed, of which 48.1% were carbapenem resistant Klebsiella pneumoniae (CRKp), 25.1% carbapenem resistant Escherichia coli (CREc), and 26.8% represented 72 other carbapenem resistant species. Carbapenem resistant strains were mostly associated with adults and isolated from urine samples (36.9% of CRKp and 66.6% of CREc) followed by respiratory samples (26.95% for CRKp) and soft tissue samples (19.5% for CRKp). Over the studied period carbapenem resistance rates remained high, especially in K. pneumoniae, and in 2021 were equivalent to 67.6% for imipenem, 76.2% for meropenem, and 91.6% for ertapenem. Nevertheless, there was a statistically significant decreasing trend for imipenem and meropenem resistance in Klebsiella species (p < 0.01) while the decrease in ertapenem resistance was non-significant. Concerning E. coli, there was a statistically significant decreasing trend for meropenem and imipenem resistance over the 12 years, while ertapenem resistance increased significantly with 83.8% of E. coli exhibiting ertapenem resistance in 2021. Resistance rates to ceftazidime and cefotaxime remained higher than 90% (in 2021) for CRKp and cefotaxime rates increased to 90.5% in 2021 for CREc. Starting 2014, resistance to colistin and tigecycline was observed in carbapenem resistant Enterobacterales. CRE were associated with a higher mortality (RR: 6.3), admission to ICU (RR 3.9), and increased length of stay (LOS; 10 excess inpatient days per CRE case).

CONCLUSION

This study supports the need to monitor CRE in the UAE and draws attention to the significant increase of ertapenem resistance in E. coli. Future surveillance analysis should include a genetic description of carbapenem resistance to provide new strategies.

Evaluation of Efficacy of Fosfomycin for the Treatment of Patients with Lower Urinary Tract Infections (UTIs)

Introduction: Until now, there have been few investigations on the efficacy of fosfomycin in the treatment of patients with uncomplicated urinary tract infections (UTIs). The present study is aimed to examine how fosfomycin affects females with lower UTIs. Methods:A total of 200 female patients who visited the women's clinic at Amir-Al-Momenin Hospital between 2020 and 2021 were examined in the present study. Patients were randomly divided into two groups of 100 people each, with one group receiving fosfomycin (a single 3 g dose) and the other one receiving cephalexin (a five-day regimen at 0.5 g four times daily). Then, one week and one month after treatment, the patients underwent a urine culture test. The data were collected and further analyzed in SPSS statistics software version 26. Results:According to the study findings, the mean age of females suffering from lower UTI was 25.45 ± 5.85 years. Besides, the collected data revealed that 85.5% of females diagnosed with lower UTI had E. coli. In addition, the frequency of females with Staphylococcus saprophyticus, Proteus spp and Klebsiella were 9%, 3% and 2.5%, respectively. Also, the frequency of women with UTI for E. coli, Staphylococcus saprophyticus, Proteus spp and Klebsiella were 85.5%, 9%, 3.2% and 2.5%, respectively. One month after treatment, urine culture showed positive results in 98% of patients who were treated with fosfomycin and 95% of those who received cephalexin. Conclusion:Fosfomycin can be administrated to treat uncomplicated UTIs in women with a high level of confidence, as an alternative to cephalexin.

A multicentre study to determine the in vitro efficacy of flomoxef against extended-spectrum beta-lactamase producing Escherichia coli in Malaysia

Background

The high burden of extended-spectrum beta-lactamase-producing (ESBL)-producing Enterobacterales worldwide, especially in the densely populated South East Asia poses a significant threat to the global transmission of antibiotic resistance. Molecular surveillance of ESBL-producing pathogens in this region is vital for understanding the local epidemiology, informing treatment choices, and addressing the regional and global implications of antibiotic resistance.

Methods

Therefore, an inventory surveillance of the ESBL-Escherichia coli (ESBL-EC) isolates responsible for infections in Malaysian hospitals was conducted. Additionally, the in vitro efficacy of flomoxef and other established antibiotics against ESBL-EC was evaluated.

Results

A total of 127 non-repetitive ESBL-EC strains isolated from clinical samples were collected during a multicentre study performed in five representative Malaysian hospitals. Of all the isolates, 33.9% were isolated from surgical site infections and 85.8% were hospital-acquired infections. High rates of resistance to cefotaxime (100%), cefepime (100%), aztreonam (100%) and trimethoprim-sulfamethoxazole (100%) were observed based on the broth microdilution test. Carbapenems remained the most effective antibiotics against the ESBL-EC, followed by flomoxef. Antibiotic resistance genes were identified by PCR. The blaCTX-M-1 was the most prevalent ESBL gene, with 28 isolates (22%) harbouring blaCTX-M-1 only, 27 isolates (21.3%) co-harbouring blaCTX-M-1 and blaTEM, and ten isolates (7.9%) co-harbouring blaCTX-M-1, blaTEM and blaSHV. A generalised linear model showed significant antibacterial activity of imipenem against different types of infection. Besides carbapenems, this study also demonstrated a satisfactory antibacterial activity of flomoxef (81.9%) on ESBL-EC, regardless of the types of ESBL genes.

Hospital-acquired bacterial pneumonia (HABP) and ventilator-associated bacterial pneumonia (VABP) in Canada: treatment update and the role of new IV antimicrobials

INTRODUCTION

Hospital-acquired bacterial pneumonia (HABP) and ventilator-associated bacterial pneumonia (VABP) continue to be common infections causing significant morbidity and mortality worldwide. The timely initiation of empiric antimicrobial therapy is essential. In this paper, we provide a focused expert opinion on the current and potential empiric antimicrobial treatment options in HABP and VABP in Canada influenced by antimicrobial resistance impacting the use of older agents as well as available new intravenous (IV) antimicrobials.

AREAS COVERED

The authors discuss treatment options for HABP and VABP in Canada. In addition, we focus on the potential role of new IV antimicrobials recently introduced to Canada. A literature search of HABP and VABP treatments was performed via PubMed (up to March 2023), using the following key words: monotherapy, combination therapy, aminoglycosides, carbapenems, cephalosporins, fluoroquinolones, penicillins as well as amoxicillin/clavulanate, ceftobiprole, ceftolozane/tazobactam, dalbavancin, and fosfomycin.

EXPERT OPINION

Empiric antimicrobial treatment for HABP and VABP in Canada continues to focus on both the severity of illness and the presence/absence of patient risk factors for antimicrobial resistance. The role of new IV antimicrobials in the empiric treatment for HABP and VABP depends on their antimicrobial activity and published data on efficacy and safety and influenced by Health Canada-approved indications.

Efficacy and safety of intravenous fosfomycin for the treatment of carbapenem-resistant Klebsiella pneumoniae

The aim of the study was to evaluate clinical and microbiological efficacy and safety of intravenous fosfomycin for the treatment of carbapenem-resistant K. pneumoniae infections. All adult inpatients receiving 48 h of intravenous fosfomycin, alone or combined with other antibiotics were included in the study. Overall favorable clinical response rate was 75.3% among 94 patients. Clinical response rates were 92.3%, 72.2% and 56.0% for urinary tract infections, bacteremia and pneumonia, respectively. Microbiological eradication was achieved in 55 of 86 patients. 30-day mortality was 33.0%. Adverse events were generally mild. Common adverse events were hypokalemia (37.2%) and hypernatremia (22.3%). Intravenous fosfomycin is an effective antibiotic option with a good safety profile for the treatment of carbapenem-resistant K. pneumoniae infections. The most favorable clinical and microbiological responses are obtained in urinary tract infections. The efficacy of the drug in more severe infections, such as pneumonia and bacteremia, is comparable to the literature.

Antibiotic management of urinary tract infections in the post-antibiotic era: a narrative review highlighting diagnostic and antimicrobial stewardship

BACKGROUND

As one of the most common indications for antimicrobial prescription in the community, the management of urinary tract infections (UTIs) is both complicated by, and a driver of, antimicrobial resistance.

OBJECTIVES

To highlight the key clinical decisions involved in the diagnosis and treatment of UTIs in adult women, focusing on clinical effectiveness and both diagnostic and antimicrobial stewardship as we approach the post-antimicrobial era.

SOURCES

Literature reviewed via directed PubMed searches and manual searching of the reference list for included studies to identify key references to respond to the objectives. A strict time limit was not applied. We prioritised recent publications, randomised trials, and systematic reviews (with or without meta-analyses) where available. Searches were limited to English language articles. A formal quality assessment was not performed; however, the strengths and limitations of each paper were reviewed by the authors throughout the preparation of this manuscript.

CONTENT

We discuss the management of UTIs in ambulatory adult women, with particular focus on uncomplicated infections. We address the diagnosis of UTIs, including the following: definition and categorisation; bedside assessments and point-of-care tests; and the indications for, and use of, laboratory tests. We then discuss the treatment of UTIs, including the following: indications for treatment, antimicrobial sparing approaches, key considerations when selecting a specific antimicrobial agent, specific treatment scenarios, and duration of treatment. We finally outline emerging areas of interest in this field.

IMPLICATIONS

The steady increase in antimicrobial resistance among common uropathogens has had a substantial affect on the management of UTIs. Regarding both diagnosis and treatment, the clinician must consider both the patient (clinical effectiveness and adverse effects, including collateral damage) and the community more broadly (population-level antimicrobial selection pressure).

Oral fosfomycin for treatment of acute bacterial prostatitis caused by multidrug-resistant Enterobacterales

To assess the feasibility of oral fosfomycin-tromethamine (FT) for the management of acute bacterial prostatitis (ABP) caused by multidrug-resistant (MDR) Enterobacterales. An observational study of adult patients diagnosed with ABP from Vall d'Hebron University Hospital (Barcelona, Spain), treated with oral FT. The primary outcome was clinical cure defined as symptom relief at the control visit, 2-4 weeks post-end of treatment. Secondary outcomes included microbiological cure, relapse, and adverse events related to the treatment. Eighteen patients with ABP caused by Enterobacterales (15 Escherichia coli and three Klebsiella pneumoniae) were included. Microorganisms were MDR bacteria [14 extended-spectrum beta-lactamase (ESBL) producers and two carbapenemase producing K. pneumoniae]. Patients received treatment with FT 3 g/48 hours during a median of 14 days (Q25-Q75, 12-17.75). Fifteen patients received a lead-in phase of intravenous suitable antimicrobial during a median of 7 days (Q25-Q75, 3.75-8). No patient had to stop treatment due to adverse events, and the only side effect reported in two patients was diarrhea. Clinical cure was achieved in all (18/18) patients and microbiological cure in 11/12 patients. After a median of follow-up of 5 months (Q25-Q75, 2-11), 2/18 patients relapsed with an orchitis and a new episode of ABP. FT is an attractive step-down therapy for ABP in patients with resistance or side effects to first-line drugs. The availability of oral treatment could reduce the use of the carbapenems, with a benefit in the quality of life of the patient, health costs, and an ecological impact. IMPORTANCE We present a brief but largest and interesting experience in which we use fosfomycin-tromethamine (FT) for the treatment of acute bacterial prostatitis (ABP) due to multiresistant bacteria. Our study provides new data that help to consider FT as a plausible alternative for treating ABP in patients with resistance or side effects to first-line drugs. The availability of an alternative oral treatment to avoid the use of the carbapenems could have important benefits in terms of quality of life of the patient, health costs, and an ecological impact.

Pivmecillinam with Amoxicillin/Clavulanic acid as step down oral therapy in febrile Urinary Tract Infections caused by ESBL-producing Enterobacterales (PACUTI)

BACKGROUND

Oral treatment alternatives for febrile urinary tract infections are limited in the era of increasing antimicrobial resistance. We aim to evaluate if the combination of pivmecillinam and amoxicillin/clavulanic acid is non-inferior to current alternatives for step-down therapy in adult patients with febrile urinary tract infection.

METHODS

We plan to perform an investigator-initiated non-inferiority trial. Adult hospitalised patients treated with 1-5 days of intravenous antibiotics for acute febrile urinary tract infection caused by extended spectrum beta-lactamase (ESBL) producing Enterobacterales will be randomised 1:1 to either control (7-10 days of either oral ciprofloxacin 500 mg twice daily or oral trimethoprim-sulfamethoxazole 800 mg/160 mg twice daily or intravenous ertapenem 1 g once daily, depending on sex, drug allergy, glomerular filtration rate and susceptibility testing) or intervention (10 days of pivmecillinam 400 mg three times daily and amoxicillin/clavulanic acid 500/125 mg three times daily). The primary outcome will be clinical cure 10 days (+/- 2 days) after antibiotic treatment completion. Clinical cure is defined as being alive with absence of fever and return to non-infected baseline of urinary tract symptoms without additional antibiotic treatment or re-hospitalisation (for urinary tract infection) based on a centralised allocation-blinded structured telephone interview. We plan to recruit 330 patients to achieve 90% power based on a sample size simulation analysis using a two-group comparison, one-sided alpha of 2.5%, an absolute non-inferiority margin of 10% and expecting 93% clinical cure rate and 10% loss to follow-up. The primary endpoint will be analysed using generalised estimated equations and reported as risk difference for both intention-to-treat and per protocol populations. Patients are planned to be recruited from at least 10 centres in Sweden from 2023 to 2026.

DISCUSSION

If the combination of pivmecillinam and amoxicillin/clavulanic acid is found to be non-inferior to the control drugs there are potential benefits in terms of tolerability, frequency of interactions, outpatient treatment, side effects, nosocomial infections and drive for further antimicrobial resistance compared to existing drugs.

TRIAL REGISTRATION

NCT05224401. Registered on February 4, 2022.

Effectiveness of fosfomycin trometamol as oral step-down therapy for bacteraemic urinary tract infections due to MDR Escherichia coli: a post hoc analysis of the FOREST randomized trial

BACKGROUND

Fosfomycin is a potentially attractive option as step-down therapy for bacteraemic urinary tract infections (BUTI), but available data are scarce. Our objective was to compare the effectiveness and safety of fosfomycin trometamol and other oral drugs as step-down therapy in patients with BUTI due to MDR Escherichia coli (MDR-Ec).

METHODS

Participants in the FOREST trial (comparing IV fosfomycin with ceftriaxone or meropenem for BUTI caused by MDR-Ec in 22 Spanish hospitals from June 2014 to December 2018) who were stepped-down to oral fosfomycin (3 g q48h) or other drugs were included. The primary endpoint was clinical and microbiological cure (CMC) 5-7 days after finalization of treatment. A multivariate analysis was performed using logistic regression to estimate the association of oral step-down with fosfomycin with CMC adjusted for confounders.

RESULTS

Overall, 61 patients switched to oral fosfomycin trometamol and 47 to other drugs (cefuroxime axetil, 28; amoxicillin/clavulanic acid and trimethoprim/sulfamethoxazole, 7 each; ciprofloxacin, 5) were included. CMC was reached by 48/61 patients (78.7%) treated with fosfomycin trometamol and 38/47 (80.9%) with other drugs (difference, -2.2; 95% CI: -17.5 to 13.1; P = 0.38). Subgroup analyses provided similar results. Relapses occurred in 9/61 (15.0%) and 2/47 (4.3%) of patients, respectively (P = 0.03). The adjusted OR for CMC was 1.11 (95% CI: 0.42-3.29, P = 0.75). No relevant differences in adverse events were seen.

CONCLUSIONS

Fosfomycin trometamol might be a reasonable option as step-down therapy in patients with BUTI due to MDR-Ec but the higher rate of relapses would need further assessment.

Definitions of Urinary Tract Infection in Current Research: A Systematic Review

Defining urinary tract infection (UTI) is complex, as numerous clinical and diagnostic parameters are involved. In this systematic review, we aimed to gain insight into how UTI is defined across current studies. We included 47 studies, published between January 2019 and May 2022, investigating therapeutic or prophylactic interventions in adult patients with UTI. Signs and symptoms, pyuria, and a positive urine culture were required in 85%, 28%, and 55% of study definitions, respectively. Five studies (11%) required all 3 categories for the diagnosis of UTI. Thresholds for significant bacteriuria varied from 103 to 105 colony-forming units/mL. None of the 12 studies including acute cystitis and 2 of 12 (17%) defining acute pyelonephritis used identical definitions. Complicated UTI was defined by both host factors and systemic involvement in 9 of 14 (64%) studies. In conclusion, UTI definitions are heterogeneous across recent studies, highlighting the need for a consensus-based, research reference standard for UTI.

Clinical Use of Intravenous Fosfomycin in Critical Care Patients in Taiwan

This retrospective study aimed to evaluate the clinical use and side effects of fosfomycin in critically ill patients in Taiwan. Forty-two patients (mean age, 69.9 years; female, 69%) who received fosfomycin were included from a teaching hospital in Taiwan from January 2021 to December 2021. We analyzed the prescription pattern of intravenous fosfomycin and evaluated patient safety profiles, clinical successes, and microbiological cure rates. The main indication was urinary tract infections (35.6%), and the most frequently identified pathogen was Escherichia coli (18.2%). The overall clinical success was 83.4%, with one multidrug-resistant pathogen isolated from eight patients (19.0%). The average dose of fosfomycin given was 11.1 ± 5.2 g/day. The average duration of therapy was 8.7 ± 5.9 days, with a median duration of 8 days, where fosfomycin was mostly (83.3%) given in combination. Fosfomycin was given 12 hourly to a maximum number (47.6%) of cases. The incidence rates of adverse drug reactions (hypernatremia and hypokalemia) were 33.33% (14/42) and 28.57% (12/42), respectively. The overall survival rate was 73.8%. Intravenous fosfomycin may be an effective and safe antibiotic to use in combination with other drugs for empirical broad-spectrum or highly suspected multidrug-resistant infections in critically ill patients.

Treatment options for multidrug-resistant Gram-negatives in urinary tract infections

PURPOSE OF REVIEW

Infections due to multidrug-resistant (MDR) Gram-negative bacteria are challenging to treat because of limited treatment options and potential side effects of less frequently used anti-infectives. In the past few years, several new antimicrobial agents effective against MDR Gram-negatives have become available. This review focuses on the treatment options for complicated urinary tract infections (cUTIs) caused by MDR Gram-negatives.

RECENT FINDINGS

The novel combinations, betalactam or carbapenem and betalactamase inhibitor, ceftazidime/avibactam and meropenem/vaborbactam, are effective for infections caused by KPC-carbapenemase-producing pathogens. Imipenem/relebactam, another carbapenem/betalactamase inhibitor combination, has been approved for the treatment of cUTI. However, data on the efficacy of imipenem/relebactam against carbapenem-resistant pathogens is still limited. Ceftolozane/tazobactam is mainly used for the treatment of MDR Pseudomonas aeruginosa infections. For the treatment of cUTI caused by extended-spectrum betalactamases producing Enterobacterales aminoglycosides or intravenous fosfomycin should be considered.

SUMMARY

To ensure prudent use and to avoid the development of resistance to novel anti-infective substances, an interdisciplinary approach, including urologists, microbiologists, and infectious disease physicians, is strongly advised.

Urinary Tract Infections: The Current Scenario and Future Prospects

Urinary tract infections (UTIs) are among the most common bacterial infections worldwide, occurring in both community and healthcare settings. Although the clinical symptoms of UTIs are heterogeneous and range from uncomplicated (uUTIs) to complicated (cUTIs), most UTIs are usually treated empirically. Bacteria are the main causative agents of these infections, although more rarely, other microorganisms, such as fungi and some viruses, have been reported to be responsible for UTIs. Uropathogenic Escherichia coli (UPEC) is the most common causative agent for both uUTIs and cUTIs, followed by other pathogenic microorganisms, such as Klebsiella pneumoniae, Proteus mirabilis, Enterococcus faecalis, and Staphylococcus spp. In addition, the incidence of UTIs caused by multidrug resistance (MDR) is increasing, resulting in a significant increase in the spread of antibiotic resistance and the economic burden of these infections. Here, we discuss the various factors associated with UTIs, including the mechanisms of pathogenicity related to the bacteria that cause UTIs and the emergence of increasing resistance in UTI pathogens.

Can fosfomycin be an alternative therapy for infections caused by E. coli harbouring dual resistance: NDM and four-amino acid insertion in PBP3?

NDM-expressing Escherichia coli infections are challenging to treat, due to limited treatment options. E. coli with four-amino acid inserts (YRIN/YRIK) are also common in India and it has been reported to reduce the susceptibility to aztreonam/avibactam and the clinically used triple combination ceftazidime/avibactam with aztreonam. Thus, there is a severe dearth of antibiotics to treat infections of NDM + PBP3 insert E. coli. In this study, we determined the susceptibility of E. coli with NDM and PBP3 insert to fosfomycin as an alternative option to treat serious infections. Non-duplicate well-characterized NDM-expressing (without or with co-expression of OXA-48-like) E. coli isolates (n = 213) subsequently carrying four-amino acid inserts in PBP3 were included in this study. MICs of fosfomycin were determined by the agar dilution method with glucose-6-phosphate supplementation, while for other comparators the broth microdilution method was used. Collectively, 98% of NDM-expressing E. coli isolates with PBP3 insert were susceptible to fosfomycin at the MIC of ≤32 mg/L. Resistance to aztreonam was noticed in 38% of the tested isolates. Putting together fosfomycin's in vitro activity, clinical efficacy and safety in randomized controlled trials, we conclude that fosfomycin could be considered as an alternative option to treat infections caused by E. coli harbouring NDM and PBP3 insert resistance mechanisms.

Treatment of severe infections caused by ESBL or carbapenemases-producing Enterobacteriaceae

Enterobacteriaceae are the most frequent pathogens in the Intensive Care Unit. Due to their safety and activity, β-Lactams (BL) and carbapenems represented the most common strategy adopted against these germs. The increasing exposure to these molecules led to the development of several types of antimicrobial resistance as the expression of extended-spectrum β-lactamases (ESBLs) and carbapenemases. Great molecular variability exists among these enzymes, with significant clinical impact. To limit morbidity and mortality, old antibiotics were tested and represent viable alternatives for specific types of infections, or once the spectrum of susceptibility of each germ has been determined. Alongside, new molecules have been specifically designed but enzyme molecular variability prevents the existence of one single antibiotic which fits for all. Therefore, a quicker identification of the molecular identity of each germ, together with the knowledge of the activity spectrum of each antibiotic is crucial to tailor the therapy and make it effective.

Current and Emerging Treatment Options for Multidrug Resistant Escherichia coli Urosepsis: A Review

Escherichia coli is a versatile commensal and pathogenic member of the human microflora. As the primary causative pathogen in urosepsis, E. coli places an immense burden on healthcare systems worldwide. To further exacerbate the issue, multi drug resistance (MDR) has spread rapidly through E. coli populations, making infections more troublesome and costlier to treat. This paper aimed to review the literature concerning the development of MDR in uropathogenic E. coli (UPEC) and explore the existing evidence of current and emerging treatment strategies. While some MDR strains maybe treated with β-lactam-β-lactamase inhibitor combinations as well as cephalosporins, cephamycin, temocillin and fosfomycin, current treatment strategies for many MDR UPEC strains are reliant on carbapenems. Carbapenem overreliance may contribute to the alarming dissemination of carbapenem-resistance amongst some UPEC communities, which has ushered in a new age of difficult to treat infections. Alternative treatment options for carbapenem resistant UPEC may include novel β-lactam-β-lactamase or carbapenemase inhibitor combinations, cefiderocol, polymyxins, tigecycline, aminoglycosides or fosfomycin. For metallo-β-lactamase producing strains (e.g., NDM, IMP-4), combinations of cefazidime-avibacam with aztreonam have been used. Additionally, the emergence of new antimicrobials brings new hope to the treatment of such infections. However, continued research is required to successfully bring these into the clinic for the treatment of MDR E. coli urosepsis.

Controversies over the management of infections caused by Amp-C- and ESBL-producing Enterobacterales : what questions remain for future studies?

PURPOSE OF REVIEW

The continuous rise in infections caused by third-generation cephalosporin-resistant Enterobacterales (e.g. extended-spectrum beta-lactamase- or AmpC-producing Enterobacterales ) is a major health concern. Carbapenems are regarded as the antibiotics of choice for the treatment of these infections. However, their indiscriminant use is not without consequences, and has contributed to the emergence of carbapenem-resistant Enterobacterales .In this review, we discuss the available evidence supporting the use of other betalactams, nonbetalactams and the new betalactams/beta-lactamase inhibitors (BLA/BLI) to treat these infections. We also analyze unresolved issues in this field.

RECENT FINDINGS

Piperacillin tazobactam (PTZ) was classically recommended as a carbapenem-sparing agent. However, data have emerged against its use and it is now a controversial recommendation. IDSA, European and British guidelines reject the empirical use of PTZ for these pathogens, reserving its use for rare clinical situations.Other issues that continue to generate debate are the use of extended infusion (3 h) PTZ, the use of older antibiotics, a shortened course of carbapenems and reserving the new BLA/BLI for these infections.

SUMMARY

New treatment strategies should be based on clinical evidence, local epidemiology and the microbiological activity of these drugs.

Determining the in vitro susceptibility of tebipenem, an oral carbapenem, against third-generation cephalosporin-resistant Escherichia coli and Klebsiella pneumoniae isolated from bloodstream infections

Background

Antimicrobials for bloodstream infections due to ESBL- and AmpC-producing Escherichia coli and Klebsiella pneumoniae are significantly limited due to widespread antimicrobial resistance. Tebipenem, an oral carbapenem, exhibits stability against these resistance mechanisms and may prove an attractive alternative.

Methods

The in vitro susceptibility of tebipenem was assessed against previously whole-genome sequenced ESBL- and AmpC-producing E. coli (274 isolates) and K. pneumoniae (42 isolates) derived from bloodstream infections using broth microdilution testing. Resulting tebipenem MICs were compared with those of other carbapenems previously tested against the isolate collection. Tebipenem activity was also compared against those isolates expressing co-resistance to the common oral antibiotics ciprofloxacin and trimethoprim/sulfamethoxazole.

Results

The tebipenem MIC₉₀ value was found to be 0.03 mg/L for E. coli and 0.125 mg/L for K. pneumoniae. For E. coli, the tebipenem MIC₉₀ value was equivalent to that of meropenem, 2-fold lower than that of doripenem, and 8-fold and 4-fold lower than that of imipenem and ertapenem, respectively. For K. pneumoniae, the tebipenem MIC₉₀ value was 2-fold higher than that of meropenem, equivalent to that of doripenem, and 4-fold and 2-fold lower than that of imipenem and ertapenem, respectively. Tebipenem MICs were also unaffected by the expression of co-resistance to ciprofloxacin and trimethoprim/sulfamethoxazole.

Conclusions

The in vitro activity of tebipenem was unaffected by the production of ESBL and AmpC enzymes. Tebipenem also retained its activity against those isolates expressing co-resistance to ciprofloxacin and trimethoprim/sulfamethoxazole. These findings therefore highlight tebipenem as a potential option for the treatment of invasive MDR infections.

Extended-spectrum β-lactamase-producing and carbapenem-resistant Enterobacterales bloodstream infection after solid organ transplantation: Recent trends in epidemiology and therapeutic approaches

Background

Infections caused by multidrug‐resistant gram‐negative bacilli (MDR GNB), in particular extended‐spectrum β‐lactamase‐producing (ESBL‐E) and carbapenem‐resistant Enterobacterales (CRE), pose a major threat in solid organ transplantation (SOT). Outcome prediction and therapy are challenging due to the scarcity of randomized clinical trials (RCTs) or well‐designed observational studies focused on this population.

Methods

Narrative review with a focus on the contributions provided by the ongoing multinational INCREMENT‐SOT consortium (ClinicalTrials identifier NCT02852902) in the fields of epidemiology and clinical management.

Results

The Spanish Society of Transplantation (SET), the Group for Study of Infection in Transplantation of the Spanish Society of Infectious Diseases and Clinical Microbiology (GESITRA‐SEIMC), and the Spanish Network for Research in Infectious Diseases (REIPI) recently published their recommendations for the management of MDR GNB infections in SOT recipients. We revisit the SET/GESITRA‐SEIMC/REIPI document taking into consideration new evidence that emerged on the molecular epidemiology, prognostic stratification, and treatment of post‐transplant ESBL‐E and CRE infections. Results derived from the INCREMENT‐SOT consortium may support the therapeutic approach to post‐transplant bloodstream infection (BSI). The initiatives devoted to sparing the use of carbapenems in low‐risk ESBL‐E BSI or to repurposing existing non‐β‐lactam antibiotics for CRE in both non‐transplant and transplant patients are reviewed, as well as the eventual positioning in the specific SOT setting of recently approved antibiotics.

Conclusion

Due to the clinical complexity and relative rarity of ESBL‐E and CRE infections in SOT recipients, multinational cooperative efforts such as the INCREMENT‐SOT Project should be encouraged. In addition, RCTs focused on post‐transplant serious infection remain urgently needed.