Multimodal Interventions to Prevent and Control Carbapenem-Resistant Enterobacteriaceae and Extended-Spectrum β-Lactamase Producer-Associated Infections at a Tertiary Care Hospital in Egypt

Effectiveness of Pre-Transplant Screening for High-Priority Multidrug-Resistant Pathogens on Pre-Engraftment Infections After Hematopoietic Stem Cell Transplantation

Objective

Owing to the rising incidence of multidrug-resistant organisms (MDRO) and the high mortality rates associated with such bacterial infections post-hematopoietic stem cell transplantation (HSCT), we investigated the MDRO colonization rate prior to transplantation using an active surveillance approach and determined its impact on subsequent infection during the pre-engraftment period.

Methods

A single-center observational study was conducted, and surveillance cultures from multiple body sites, including the rectum, nasal cavity, and groin, were performed at admission to determine MDRO colonization. Serological tests were used to detect certain viruses and toxoplasmosis before HSCT.

Results

In the pre-transplant setting, 59 MDRO were recovered from the 40 HSCT recipients. Of the 59 isolates recovered from one or more body sites, 29 were positive for methicillin-resistant Staphylococcus aureus (MRSA), 7 for carbapenem-resistant Enterobacterales (CRE), and 23 were positive for extended-spectrum β-lactamase (ESBLs). Serological assessment before HSCT revealed active or reactivation of latent infection with cytomegalovirus (7.5%), Epstein-Barr virus (EBV; 5%), and Toxoplasma gondii (2.5%) among HSCT patients. In terms of factors associated with pre-engraftment infections, the type of transplant (p=0.04) was statistically significant, whereas other factors, such as age, sex, and underlying conditions, were not. In post-transplant settings, bloodstream infections (BSIs) were documented in 2 allogeneic HSCT patients (5%), and the isolated microorganisms were ESBL-producing E. coli and non-MDR Acinetobacter baumannii.

Conclusion

Active screening cultures are a helpful tool for identifying patients colonized by MDRO or relevant viruses before HSCT, and for predicting those at risk of developing subsequent pre-engraftment infections. Additionally, active screening may aid in predicting those who are likely to develop subsequent pre-engraftment infections Our findings highlight the importance of pre-transplant screening for high-priority multidrug-resistant pathogens and the application of infection control interventions after HSCT.

Comparative performance of biofire pneumonia panel and standard culture-based methods for diagnosing pneumonia in critically ill patients: Impact on antibiotic stewardship

INTRODUCTION

Lower respiratory tract infections (LRTIs) are a common cause of morbidity and mortality worldwide. Accurate identification of the pathogens causing LRTIs is crucial for ensuring of diagnostic and antibiotic stewardship. The Biofire Pneumonia Panel (BFPP) is a molecular diagnostic test that allows rapid detection of various bacterial and viral pathogens. In this study, we compared the performance of BFPP with standard culture methods for the detection of pathogens.

MATERIALS AND METHODS

Respiratory samples from 70 patient with suspected LRTIs were tested using both BFPP and standard culture methods. The distribution of isolated bacterial pathogens was analyzed, and the sensitivity and specificity of BFPP were calculated. Additionally, the performance of BFPP in detecting antimicrobial resistance genes was evaluated. The results were compared with those obtained from VITEK-2 antimicrobial susceptibility testing and culture-based methods.

RESULTS

Among the suspected LRTI cases, BFPP identified a single pathogen in 32.8% of cases and multiple pathogens in 40% of cases. The standard culture method detected a single pathogen in 47.1% of cases. BFPP showed a sensitivity of 93.9% and a specificity of 45.9% for the total sample. The performance of BFPP in detecting antimicrobial resistance genes varied for different pathogens with overall sensitivity of 40.1% and specificity of 95.9%.

CONCLUSION

The Biofire Pneumonia Panel (BFPP) demonstrated high sensitivity for several bacterial pathogens, indicating its potential as a rapid diagnostic tool. However, its performance varied for different microorganisms, and it had limitations in detecting certain pathogens and antimicrobial resistance genes for which still required more further studies to explore different resistance gene mechanism that can be incorporated in this panel in future. The BFPP can complement standard culture methods as a rapid tool in the diagnosis of LRTIs.

Detection of phylogrouping, adhesin, and extended spectrum β-lactamases genes in hospital acquired uropathogenic Escherichia coli isolates

BACKGROUND

It has been interesting to compare the levels of antimicrobial resistance and the virulence characteristics of uropathogenic Escherichia coli (UPEC) strains of certain phylogenetic groups. The purpose of this study was to identify the frequency of phylogenetic groups, adhesin genes, antibiotic sensitivity patterns, and extended spectrum-lactamases (ESBLs) genes in hospital-acquired UPEC.

METHODS

After UPEC isolation, the disc diffusion method was used to assess its susceptibility to antibiotics. Combination disc testing confirmed the existence of ESBL producers. Polymerase chain reaction (PCR) was used to detect genes for adhesin and ESBLs.

RESULTS

One hundred and twenty-eight E. coli were isolated which had the highest resistance to tetracycline (96%) followed by cefoxitin (93%), cefepime (92%), ceftazidime (79%), aztreonam (77%) and sulfamethoxazole -trimethoprim (75%). About 57% of isolates were phenotypically ESBLs positive and they were confirmed by PCR. B2 phylogroup (41%) was the most frequent in E. coli isolates then group D (30%), group A (18%), and lastly group B1 (11%). ESBLs genes were more significantly prevalent in phylogroups B2 and D than other phylogroups (P < 0.001). Regarding adhesin genes, both fim H and afa were more significantly associated with group B2 than other groups (P < 0.009, < 0.032), respectively. In ESBL-positive isolates, both genes were more significantly detected compared to negative ones (P < 0.001).

CONCLUSION

Phylogroups B2 and D of UPEC are important reservoirs of antimicrobial resistance and adhesion genes. Detection of ESBL-producing E. coli is important for appropriate treatment as well as for effective infection control in hospitals.

Propranolol restores susceptibility of XDR Gram-negative pathogens to meropenem and Meropenem combination has been evaluated with either tigecycline or amikacin

BACKGROUND

Infection with extensive-drug-resistant (XDR) carbapenem-resistant (CR) Gram-negative bacteria (GNB) are viewed as a serious threat to human health because of the limited therapeutic options. This imposes the urgent need to find agents that could be used as adjuvants or combined with carbapenems to enhance or restore the susceptibility of XDR CR- GNB. Therefore, this study aimed to examine the effect of propranolol (PR) in combination with Meropenem (MEM) on the susceptibility profile of XDR CR-GNB recovered from severely infected patients as well as to evaluate combining MEM with either tigecycline (TGC) or amikacin (AK).

METHODS

A total of 59 non-duplicate CR- GNB were investigated for carbapenemase production by the major phenotypic methods. Molecular identification of five major carbapenemase-coding genes was carried out using polymerase chain reactions (PCR). Antimicrobial susceptibility tests were carried out using standard methods. Phenotypic and genotypic relatedness was carried out using the heatmap and ERIC PCR analysis. PR, 0.5 -1 mg/mL against the resulting non-clonal XDR CR-GNB pathogens were evaluated by calculating the MIC decrease factor (MDF). A combination of MEM with either AK or TGC was performed using the checkerboard assay.

RESULTS

A total of 21 (35.6%) and 38 (64.4%) CR-GNB isolates were identified as enterobacterial isolates (including 16 (27.1%) Klebsiella Pneumoniae and 5 (8.5%) Escherichia coli) and non-fermentative bacilli (including, 23 (39%), Acinetobacter baumannii, and 15 (25.4%) Pseudomonas aeruginosa). The heatmap and ERIC PCR analysis resulted in non-clonal 28 XDR CR isolates. PR, at a concentration of 0.5 mg /ml, decreased MICs values of the tested XDR CR isolates (28; 100%) and restored susceptibility of only 4 (14.3%) isolates. However, PR (1 mg/mL) when combined with MEM has completely (28; 100%) restored the susceptibility of the tested XDR CR- GNB to MEM. The MEM + AK and MEM + TGC combination showed mostly additive effects (92.8% and 71.4%, respectively).

CONCLUSION

PR at a concentration of 1 mg/mL restored the susceptibility of XDR CR- GNB to MEM which is considered a promising result that should be clinically investigated to reveal its suitability for clinical use in patients suffering from these life-threatening pathogens.

Next-Generation Polymyxin Class of Antibiotics: A Ray of Hope Illuminating a Dark Road

Although new-generation antimicrobials, in particular β-lactam/β-lactamase inhibitors, have largely replaced polymyxins in carbapenem-resistant Gram-negative bacterial infections, polymyxins are still needed for carbapanem-resistant Acinetobacter baumannii infections and in settings where novel agents are not readily available. Despite their potent in vitro activity, the clinical utility of polymyxins is significantly limited by their pharmacokinetic properties and nephrotoxicity risk. There is significant interest, therefore, in developing next-generation polymyxins with activity against colistin-resistant strains and lower toxicity than existing polymyxins. In this review, we aim to present the antibacterial activity mechanisms, in vitro and in vivo efficacy data, and toxicity profiles of new-generation polymyxins, including SPR206, MRX-8, and QPX9003, as well as the general characteristics of old polymyxins. Considering the emergence of colistin-resistant strains particularly in endemic regions, the restoration of the antimicrobial activity of polymyxins via PBT2 is also described in this review.

Extended-Spectrum Beta-Lactamase and Carbapenem-Resistant Gram-Negative Pathogens in Makkah, Saudi Arabia

Background

This study aimed to determine the prevalence of extended-spectrum-beta-lactamase (ESBL) and carbapenem-resistant gram-negative bacteria (GNB) isolated from patients at the King Faisal Hospital in Makkah, Saudi Arabia.

Methods

In this cross-sectional study, a total of 298 patients admitted to the intensive care unit for 48 hours and who had a central venous catheter were selected using a census sampling method. Only patients with ESBL and carbapenem-resistant GNB-isolated organisms (175 patients) were included. The susceptibility test of GNB was carried out according to the standard recommendations. The identified strains were tested in-vitro against several antimicrobial drugs. Statistical analysis was performed using SPSS version 24.

Results

36(20.6%) of samples were ESBL-producing GNB, whereas 139(79.4%) were carbapenem-resistant GNB. The pooled proportional estimates of ESBL-producing GNB Escherichia coli, Klebsiella pneumoniae, and other GNB were 44.4%, 41.6%, and 14.0%, respectively; the pooled proportional estimates of carbapenem resistance GNB Klebsiella pneumoniae, Acinetobacter baumannii complex/hemolyticus and other GNB were 82.8%, 10.8%, and 6.4%, respectively. All ESBL-producing GNB and carbapenem-resistance GNB were multidrug-resistant pathogens. The highest carbapenem resistance GNB 139(100%) was to ampicillin, and the lowest 122(87.7%) was to Amoxicillin/clavulanic acid (Amox/clav). All ESBL-producing GNB 36 (100%) were resistant to cefotaxime, and 35 (97.2%) were resistant to ampicillin, cefuroxime, cefepime, and ceftazidime. Additionally, the effective antibiotic against ESBL-producing GNB was imipenem.

Conclusion

Antibiotic utilization measures appear to contribute to the control of the emergence of multidrug-resistant pathogens such as ESBL and carbapenem-resistant GNB. Strict adherence to well-accepted infection control guidelines along with caution in using broad-spectrum antimicrobial agents represents the best strategy for preventing the emergence and spread of multidrug-resistant pathogens.

Impact of Antimicrobial Stewardship Interventions to Improve Antibiotic Prescribing for Hospital Inpatients in Africa: A Systematic Review and Meta-analysis

BACKGROUND

Antimicrobial stewardship (AMS) interventions to improve antibiotic use are being implemented in Africa, but their impact is not fully known.

AIM

To estimate the effectiveness of interventions to improve antibiotic prescribing for hospital inpatients.

METHODS

Systematically searched for studies from PubMed, Embase, African Journals online and Google scholar from January 2010 to July 2022. Studies were included if they reported the impact of AMS interventions on outcomes of interest for hospital inpatients in Africa. Risk of bias was evaluated using the Cochrane Effective Practice and Organization of Care guidelines and the National Heart, Lung and Blood Institute tool. Findings were summarized in tables and meta-analyses were performed using random-effects models.

FINDINGS

Twenty-eight studies were included, 89% being uncontrolled before and after studies. Most interventions employed were multifaceted and found to be effective, evidenced by increased compliance, reduction in antibiotic utilization and cost, and slight reduction or no difference in mortality and length of hospital stay (LOS). Meta-analysis generated a relative risk of 0.82 (95% CI: 0.70∼0.97) for mortality, and a standard mean difference of -0.30 (95% CI: -0.41∼-0.19) for LOS. Generally, a decrease in resistance to most microorganisms was observed. Despite an increase in the number of AMS studies conducted in Africa, the studies lack in most quality design features for AMS studies.

CONCLUSION

Antimicrobial stewardship interventions are likely to be effective, however efforts are still required to align the study design with the quality design features required for validity and to inform practice.

Febrile illness of bacterial etiology in a public fever hospital in Egypt: High burden of multidrug resistance and WHO priority Gram negative pathogens

INTRODUCTION

Contemporary emergence of multidrug resistance (MDR) urges regular updates on circulating pathogens and their antimicrobial resistance profiles. We aimed to identify the burden of MDR and World Health Organization (WHO) priority Gram negative pathogens among patients admitted with febrile illness to Abbassia Fever Hospital, a major Public Fever Hospital in Egypt. The carbapenemase- and extended spectrum beta-lactamases (ESBLs)-encoding genes carried by the isolates were also identified.

METHODS

A total of 9602 clinical specimens were collected from febrile patients during 2018 and 2019. The recovered bacterial isolates were examined for antimicrobial susceptibility using disk diffusion test. Susceptibility to colistin was tested using E-test. ESBLs production was phenotypically and genotypically analyzed.

RESULTS

A total of 790 bacterial isolates (612 Gram negative and 178 Gram positive) were recovered. A percentage of 77.6%, and 62.9% of the Gram negative and positive isolates showed MDR phenotype, respectively. WHO priority pathogens were abundant, including carbapenem-resistant (CR) Enterobacterales (105/187; 56.1%) and CR glucose non-fermenters (82/187; 43.8%) such as: A. baumannii (55; 29.4%), P. aeruginosa (27; 14.4%). Carbapenemase- and ESBLs-encoding genes were detected in 56.1% and 30.8% of Enterobacterales and in 43.8% and 46.3% of glucose non-fermenters, respectively. Antimicrobials such as fosfomycin and chloramphenicol retained good activities against MDR Gram negative pathogens.

CONCLUSIONS

This study highlights the regional burden of MDR and priority Gram negative pathogens. The obtained data are of relevant medical importance for implementation of evidence-based antimicrobial stewardship programs and for tailoring the existing empirical treatment guidelines.

Evaluation of the BioFire FilmArray Pneumonia Panel Plus to the Conventional Diagnostic Methods in Determining the Microbiological Etiology of Hospital-Acquired Pneumonia

Hospital-acquired pneumonia (HAP) is a substantial public health issue that is associated with high mortality rates and is complicated by an arsenal of microbial etiologies, expressing multidrug-resistant phenotypes, rendering relatively limited therapeutic options. BioFire FilmArray Pneumonia Panel plus (BFPP) is a simple multiplexed PCR system that integrates sample preparation, nucleic acid extraction, amplification, and analysis of microbial etiology, with a turnaround time of about one hour. In comparison to standard culture methods, BFPP is simpler, easier to perform, and can simultaneously detect the most common pathogens involved in lower respiratory tract infections (34 targets). Accordingly, we evaluated the diagnostic performance of the multiplexed BFPP for the rapid detection of 27 clinically relevant respiratory pathogens and 7 genetic markers among 50 HAP cases admitted to the intensive care unit (ICU), who submitted mini-bronchoalveolar (mBAL) specimens. In comparison to standard culture methods, BFPP showed an overall sensitivity of 100% [95% CI; 90-100] and overall specificity of 90% [95% CI; 87.4-92.5] among all the tested bacterial targets. BFPP identified 11 viral targets (22%) among the tested specimens. The BFPP semi-quantitative analysis showed a concordance rate of 47.4% among positive culture specimens. For the investigation of the antibiotic resistance genes, BFPP showed a positive percent agreement (PPA), a negative percent agreement (NPA), and an overall percent agreement (OPA), reaching 97% [95% CI; 90-100], 95% [95% CI; 91.5-97], and 95% [95% CI; 93-97], respectively, with standard antibiotic sensitivity testing. In conclusion, BFPP has the potential to enhance the rapid microbiological diagnosis of HAP cases, and could aid in tailoring appropriate antibiotic therapies.

The Role of Colistin in the Era of New β-Lactam/β-Lactamase Inhibitor Combinations

With the current crisis related to the emergence of carbapenem-resistant Gram-negative bacteria (CR-GNB), classical treatment approaches with so-called “old-fashion antibiotics” are generally unsatisfactory. Newly approved β-lactam/β-lactamase inhibitors (BLBLIs) should be considered as the first-line treatment options for carbapenem-resistant Enterobacterales (CRE) and carbapenem-resistant Pseudomonas aeruginosa (CRPA) infections. However, colistin can be prescribed for uncomplicated lower urinary tract infections caused by CR-GNB by relying on its pharmacokinetic and pharmacodynamic properties. Similarly, colistin can still be regarded as an alternative therapy for infections caused by carbapenem-resistant Acinetobacter baumannii (CRAB) until new and effective agents are approved. Using colistin in combination regimens (i.e., including at least two in vitro active agents) can be considered in CRAB infections, and CRE infections with high risk of mortality. In conclusion, new BLBLIs have largely replaced colistin for the treatment of CR-GNB infections. Nevertheless, colistin may be needed for the treatment of CRAB infections and in the setting where the new BLBLIs are currently unavailable. In addition, with the advent of rapid diagnostic methods and novel antimicrobials, the application of personalized medicine has gained significant importance in the treatment of CRE infections.