Carbapenem-Resistant Enterobacteriaceae Posing a Dilemma in Effective Healthcare Delivery

Broad-spectrum antibiotic prophylaxis in tumor and infected orthopedic surgery-the prospective-randomized, microbiologist-blinded, stratified, superiority trials: BAPTIST Trials

BACKGROUND

The perioperative antibiotic prophylaxis with 1st or 2nd generation cephalosporins is evidence-based in orthopedic surgery. There are, however, situations with a high risk of prophylaxis-resistant surgical site infections (SSI).

METHODS

We perform a superiority randomized controlled trial with a 10% margin and a power of 90% in favor of the broad-spectrum prophylaxis. We will randomize orthopedic interventions with a high risk for SSI due to selection of resistant pathogens (open fractures, surgery under therapeutic antibiotics, orthopedic tumor surgery, spine surgery with American Society of Anesthesiologists (ASA) score ≥ 3 points) in a prospective-alternating scheme (1:1, standard prophylaxis with cefuroxime versus a broad-spectrum prophylaxis of a combined single-shot of vancomycin 1 g and gentamicin 5 mg/kg parenterally). The primary outcome is "remission" at 6 weeks for most orthopedic surgeries or at 1 year for surgeries with implant. Secondary outcomes are the risk for prophylaxis-resistant SSI pathogens, revision surgery for any reason, change of antibiotic therapy during the treatment of infection, adverse events, and the postoperative healthcare-associated infections other than SSI within 6 weeks (e.g., urine infections or pneumonia). With event-free surgeries to 95% in the broad-spectrum versus 85% in the standard prophylaxis arm, we need 2 × 207 orthopedic surgeries.

DISCUSSION

In selected patients with a high risk for infections due to selection of prophylaxis-resistant SSI, a broad-spectrum combination with vancomycin and gentamycin might prevent SSIs (and other postoperative infections) better than the prophylaxis with cefuroxime.

TRIAL REGISTRATION

ClinicalTrial.gov NCT05502380. Registered on 12 August 2022. Protocol version: 2 (3 June 2022).

Molecular characterization of IncFII plasmid carrying blaNDM-5 in a Salmonella enterica serovar Typhimurium ST34 clinical isolate in China

IMPORTANCE

In this study, an IncFII plasmid pIncFII-NDM5 carrying blaNDM-5 was found in carbapenem-resistant Salmonella enterica serovar Typhimurium (S. enterica serovar Typhimurium), which has conjugative transferability and carried blaNDM-5, bleMBL, mph(A), and blaTEM-1 four resistance genes that can mediate resistance to multiple antibiotics including cephalosporins, beta-lactamase inhibitor combinations, carbapenems, and macrolides. Phylogenetic analysis showed that 1104-65 and 1104-75 were closely related to other S. enterica serovar Typhimurium in this area. The above-mentioned S. enterica serovar Typhimurium chromosome carries blaCTX-M-55, qnrS1, and tet(A) genes, so the antibiotic resistance of isolates will be further enhanced after obtaining the pIncFII_NDM5-like plasmid. Meanwhile, we discovered a novel genetic structure of blaNDM-5 mediated by the IS26 composite transposon, which will expand our understanding of the emergence and spread of carbapenem-resistance genes. Altogether, the presence of the IncFII plasmid pIncFII-NDM5 further underscores the need for vigilant surveillance and appropriate infection control measures to mitigate the impact of carbapenem-resistant S. enterica serovar Typhimurium in clinical settings.

In Vitro Activity of New β-Lactamase Inhibitor Combinations against blaNDM, blaKPC, and ESBL-Producing Enterobacteriales Uropathogens

Antibiotic resistance in uropathogens has increased substantially and severely affected treatment of urinary tract infections (UTIs). Lately, some new formulations, including meropenem/vaborbactam (MEV), ceftazidime/avibactam (CZA), and ceftolozane/tazobactam (C/T) have been introduced to treat infections caused by drug-resistant pathogens. This study was designed to screen Enterobacteriales isolates from UTI patients and to assess their antimicrobial resistance pattern, particularly against the mentioned (new) antibiotics. Phenotypic screening of extended-spectrum β-lactamase (ESBL) and carbapenem resistance was followed by inhibitor-based assays to detect K. pneumoniae carbapenemase (KPC), metallo-β-lactamase (MBL), and class D oxacillinases (OXA). Among 289 Enterobacteriales, E. coli (66.4%) was the most predominant pathogen, followed by K. pneumoniae (13.8%) and P. mirabilis (8.3%). The isolates showed higher resistance to penicillins and cephalosporins (70-87%) than to non-β-lactam antimicrobials (33.2-41.5%). NDM production was a common feature among carbapenem-resistant (CR) isolates, followed by KPC and OXA. ESBL producers were susceptible to the tested new antibiotics, but NDM-positive isolates appeared resistant to these combinations. KPC-producers showed resistance to only C/T. ESBLs and carbapenemase encoding genes were located on plasmids and most of the genes were successfully transferred to recipient cells. This study revealed that MEV and CZA had significant activity against ESBL and KPC producers.

Review and analysis of the overlapping threats of carbapenem and polymyxin resistant E. coli and Klebsiella in Africa

BACKGROUND

Carbapenem-resistant Enterobacterales are among the most serious antimicrobial resistance (AMR) threats. Emerging resistance to polymyxins raises the specter of untreatable infections. These resistant organisms have spread globally but, as indicated in WHO reports, the surveillance needed to identify and track them is insufficient, particularly in less resourced countries. This study employs comprehensive search strategies with data extraction, meta-analysis and mapping to help address gaps in the understanding of the risks of carbapenem and polymyxin resistance in the nations of Africa.

METHODS

Three comprehensive Boolean searches were constructed and utilized to query scientific and medical databases as well as grey literature sources through the end of 2019. Search results were screened to exclude irrelevant results and remaining studies were examined for relevant information regarding carbapenem and/or polymyxin(s) susceptibility and/or resistance amongst E. coli and Klebsiella isolates from humans. Such data and study characteristics were extracted and coded, and the resulting data was analyzed and geographically mapped.

RESULTS

Our analysis yielded 1341 reports documenting carbapenem resistance in 40 of 54 nations. Resistance among E. coli was estimated as high (> 5%) in 3, moderate (1-5%) in 8 and low (< 1%) in 14 nations with at least 100 representative isolates from 2010 to 2019, while present in 9 others with insufficient isolates to support estimates. Carbapenem resistance was generally higher among Klebsiella: high in 10 nations, moderate in 6, low in 6, and present in 11 with insufficient isolates for estimates. While much less information was available concerning polymyxins, we found 341 reports from 33 of 54 nations, documenting resistance in 23. Resistance among E. coli was high in 2 nations, moderate in 1 and low in 6, while present in 10 with insufficient isolates for estimates. Among Klebsiella, resistance was low in 8 nations and present in 8 with insufficient isolates for estimates. The most widespread associated genotypes were, for carbapenems, blaOXA-48, blaNDM-1 and blaOXA-181 and, for polymyxins, mcr-1, mgrB, and phoPQ/pmrAB. Overlapping carbapenem and polymyxin resistance was documented in 23 nations.

CONCLUSIONS

While numerous data gaps remain, these data show that significant carbapenem resistance is widespread in Africa and polymyxin resistance is also widely distributed, indicating the need to support robust AMR surveillance, antimicrobial stewardship and infection control in a manner that also addresses broader animal and environmental health dimensions.

A systematic review of the current status of carbapenem resistance in Nigeria: Its public health implication for national intervention

Carbapenem antibiotics are considered one of the most effective and the last-resort antibiotics for the treatment of infections caused by multidrug-resistant Gram-negative bacteria. However, with the advent of carbapenem resistance, it becomes obvious that quality health-care delivery will be hampered if adequate measure is not put in place. This review assessed the prevalence of carbapenem-resistant Gram-negative bacteria (CR-GNB) and also provided an up-to-date position on carbapenem resistance (CR) in Nigeria. Three electronic databases (Google Scholar, PubMed and African Journal online) were searched for relevant literatures, and 38 articles published between January 2013 and June 2022 that met the criteria for inclusion were recruited into the study. The mean prevalence of CR in Nigeria stands at 21.3%, with the southern and northern regions documenting a mean prevalence of 22.0% and 20.9%, respectively. Most of the reviewed articles were from clinical settings (81.6%), with urine samples (38.7%) constituting the most prevalent clinical sample in which CR-GNB were detected. The preponderance of phenotypic methods (55.3%) over molecular method (44.7%), particularly the use of disk diffusion test breakpoint and Modified Hodge test was documented. The most prevalent carbapenem-resistant bacteria were Escherichia coli (50.0%) and Klebsiella pneumoniae (26.3%). The blaNDM and blaVIM were the major reported carbapenemase-encoded genes, particularly among E. coli, K. pneumoniae and Pseudomonas species. This systematic review revealed a mean prevalence of CR-GNB in Nigeria that required urgent attention. Furthermore, the detection of clinically and epidemiologically important carbapenemase coding genes is of public health importance.

Risk of polymyxin B-induced acute kidney injury with a non adjusted dose versus adjusted dose based on renal function

Aim: To observe the difference in the risk of polymyxin B (PMB)-induced acute kidney injury (AKI) with or without dose adjustment based on the patients renal function. Materials & methods: This retrospective cohort analysis was carried out in 115 patients treated with PMB from November 2018 to October 2019. Results: No significant difference in the incidence of AKI as well as secondary outcomes was observed between these two groups (47.5 vs 37.14%; p = 0.304). Conclusion: Dosing adjustment based on renal function does not significantly lower the risk of PMB-induced AKI. A non adjusted dosing strategy for PMB is recommended in patients exhibiting various levels of renal impairment.

Evaluating antimicrobial prescribing in a Tertiary Healthcare Institution in Nigeria

Background

Regular evaluation of antimicrobials prescriptions is important for optimal use.

Objective

This study determined the prescription patterns, class and costs of antimicrobials in the adult out-patient pharmacy of a Teaching Hospital in Nigeria.

Methods

A 1-year retrospective study from 1st January to 31st December 2018. The data, which included identification code, age, sex, antibiotics prescribed, number of antibiotics per prescription, number of medicines per prescription, dosage form, generic prescribing, drug on the essential drug list, and cost, were used in the analysis. The Chi-square test and Analysis of Variance were used to compare our data with the WHO–developed antimicrobial prescription Guidelines for Anatomical Therapeutic Chemical and Defined Daily Dose assignment of 2019.

Results

From 450 patient records, significantly more females (70%) were prescribed with antimicrobials (P = 0.0038). The prescription pattern showed that antimicrobials selection by class was significantly different (P < 0.0001) (top three being Amino-penicillin > Nitroimidazoles > Fluoroquinolone). In addition, age differed significantly (P < 0.0001) with 46–50 as the highest class. Dosage forms profile showed that the percentage of encounter with injections prescribed (1.8%) was less than WHO recommendation (13.4–24.1%). Most of the prescriptions (84.22%) were from the Essential Drug List. The average cost of prescriptions with two antimicrobials was the highest ($14.0807), then three ($10.7949), and one ($6.39858). The average number of drugs per prescription that had one (4.28), two (4.46), and three (5.55) antimicrobials, respectively, were more than double the average (2) recommended by WHO.

Conclusion

The study showed that most of the patterns are within limit, however, highlights the need for frequent evaluation.

Dissemination of Carbapenemases (OXA-48, NDM and VIM) Producing Enterobacteriaceae Isolated from the Mohamed VI University Hospital in Marrakech, Morocco

The emergence and spread of carbapenem-resistant Enterobacteriaceae (CRE) represent a major clinical problem and raise serious health concerns. The present study aimed to investigate and ascertain the occurrence of CRE among hospitalized patients of Mohamed VI University Hospital, Marrakech, Morocco. Biological samples were collected over a one-year period (2018). The bacterial isolates were identified by MALDI-TOF-MS. Antibiotic susceptibility testing was performed using disc diffusion and Etest. The modified Hodge test and combined disc diffusion test were used for phenotypic detection. CRE hydrolyzing enzyme encoding genes: blaOXA-48, blaKPC, blaIMP, blaVIM, and blaNDM were characterized by PCR and DNA sequencing. In total, 131 non-duplicate CRE clinical strains resistant to Ertapenem were isolated out of 1603 initial Enterobacteriaceae. Klebsiella pneumoniae was the most common species (59%), followed by Enterobacter cloacae (24%), E. coli (10%), Citrobacter freundii (3%), Klebsiellaoxycota (2%), Serratia marcescens (1%), and Citrobacter braakii (1%). Of these, 56.49%, 21.37%, 15.27%, 3.38%, and 3.05% were collected from blood, urine, pus, catheters and respiratory samples, respectively. Approximately 85.5% (112/131) of the isolates were carbapenemase producers (40 blaOXA-48, 27 blaNDM, 38 blaOXA-48 + blaNDM and 7 blaVIM). All metallo-β-lactamases isolates were NDM-1 and VIM-1 producers. This is the first documentation of blaOXA-48 genes from C. freundii and C. braakii in Morocco.

Secondary metabolites of endophytic fungi from Newbouldia laevis and Cassia tora leaves: prospecting for new antimicrobial agents

AIM

This study tries to prospect for new antimicrobial agents using some Nigerian plants Background: Antimicrobial compounds from fungi endophytes have shown great promise in mitigating the threats of resistant pathogens.

OBJECTIVE

The study evaluated the in vitro antimicrobial property of secondary metabolites of endophytic fungi isolated from Newbouldia laevis and Cassia tora leaves.

METHODS

Ten endophytic fungi were isolated from the two plants' leaves and later fermented on local rice for 21 days. Thereafter, their secondary metabolites were extracted using ethyl acetate. The antibacterial activity of the extracts on the test organisms were determined using agar diffusion and agar dilution methods, while the bioactive constituents were identified using High performance liquid chromatography coupled to diode array detector.

RESULTS

Nine of the crude extracts (NL1, NL3, NL6, NL10, NL12, CT2, CT7, CT9 and CT10) of the fungi isolates inhibited at least one of the microorganisms studied with maximum and minimum Inhibition-Zone-Diameter of 14 mm and 2 mm respectively while CT1 did not inhibit any of the tested microorganisms at tested concentrations. The extracts exhibited good antifungal activity, inhibiting the growth of both C. albicans and Trichophyton tested with an InhibitionZone-Diameter ranging between 4-8 mm and 7-14 mm respectively. The endophytic fungi extracts- CT2 and NL1- exhibited the best antimicrobial activity, inhibiting most of the tested microorganisms. HPLC-DAD analysis of the endophytic fungal extracts identified some classes of compounds such as catechin derivatives, benzoic acid derivatives and apigenin, which were previously reported to have antimicrobial potentials.

CONCLUSION

Newbouldia laevis and Cassia tora leaves house endophytic fungi capable of yielding secondary metabolites with potential as anti-infective agents.

Pharmaceutical Quality of Selected Metronidazole and Ciprofloxacin Infusions Marketed in South Eastern Nigeria

Background

Pharmaceutical products need to be of good quality and it is even more critical when it comes to life saving medicaments like infusions.

Objective

This research surveyed the quality fitness of some ciprofloxacin and metronidazole infusion samples marketed in South-eastern of Nigeria.

Methods

Using Official Compendial methods, microbiological quality, active pharmaceutical ingredients quantitation, pH and particle count tests were evaluated on eighty infusion bottles (from eight pharmaceutical companies) of each of the two drugs.

Results

Out of the sixteen brands tested, 2 metronidazole brands and 1 ciprofloxacin brand (representing 18.75% of the total 16 brands/makes) were contaminated while the remaining 13 brands (81.25%) were found sterile. The active pharmaceutical ingredients quantitative assay showed that all the brands of ciprofloxacin infusion were between the 95% and 105% limit of label claim while one metronidazole brand has <95–110% limit label claim. Six brands each of the two drugs evaluated fall below the acceptable pH range [ciprofloxacin (3.5–4.6) and metronidazole (4.8–5.2)], while the other two brands of both drugs passed the test. In the antibacterial study, Pseudomonas aeruginosa and Escherichia coli were susceptible to the ciprofloxacin (5 µg). However, Salmonella typhi recorded inhibition zone diameters within resistant and intermediate range. Peptostrepococcus spp was susceptible (at minimum inhibitory concentrations of 100 µg/mL) to all the brands of metronidazole, while none of the brands were effective on Lactobacillus spp. All the brands passed the test for particulate contamination. The particles size range was <10µm.

Conclusion

About eighty-one percent (81.25%) of the infusions have acceptable good microbiological quality. However, 18.75% that failed the tests is a concern knowing that these are lifesaving products.

Immunoinformatics and Vaccine Development: An Overview

The use of vaccines have resulted in a remarkable improvement in global health. It has saved several lives, reduced treatment costs and raised the quality of animal and human lives. Current traditional vaccines came empirically with either vague or completely no knowledge of how they modulate our immune system. Even at the face of potential vaccine design advance, immune-related concerns (as seen with specific vulnerable populations, cases of emerging/re-emerging infectious disease, pathogens with complex lifecycle and antigenic variability, need for personalized vaccinations, and concerns for vaccines' immunological safety -specifically vaccine likelihood to trigger non-antigen-specific responses that may cause autoimmunity and vaccine allergy) are being raised. And these concerns have driven immunologists toward research for a better approach to vaccine design that will consider these challenges. Currently, immunoinformatics has paved the way for a better understanding of some infectious disease pathogenesis, diagnosis, immune system response and computational vaccinology. The importance of this immunoinformatics in the study of infectious diseases is diverse in terms of computational approaches used, but is united by common qualities related to host–pathogen relationship. Bioinformatics methods are also used to assign functions to uncharacterized genes which can be targeted as a candidate in vaccine design and can be a better approach toward the inclusion of women that are pregnant into vaccine trials and programs. The essence of this review is to give insight into the need to focus on novel computational, experimental and computation-driven experimental approaches for studying of host–pathogen interactions and thus making a case for its use in vaccine development.

Multi-Antibiotic Resistance and Factors Affecting Carriage of Extended Spectrum β-Lactamase-Producing Enterobacteriaceae in Pediatric Population of Enugu Metropolis, Nigeria

Extended-spectrum β-lactamase (ESBL)-producing organisms have become a serious challenge in healthcare delivery globally. The prevalence of ESBL carriage in healthy and sick children in Enugu, Nigeria, was bacteriologically investigated in this study. Four hundred and twenty-two biological samples (mid-stream urine and feces) were bacteriologically analyzed. The isolates were screened for ESBL production using Clinical and Laboratory Standards Institute (CLSI) breakpoints. The suspected ESBL producers were confirmed using double disc synergy test method. Out of the 162 isolates screened, 32 (19.8%) were confirmed as ESBL positive, with a prevalence of 25.32% among sick children in Enugu State University Teaching Hospital (ESUTH), Parklane, Enugu and 13.89% in apparently healthy children in a community setting. Klebsiella spp. and Escherichia coli had the highest prevalence of 34.6% and 28.6%, respectively; Citrobacter spp. and Enterobacter spp. were 18.2% and 16.7%, respectively. The ESBL positive isolates were resistant to sulfamethoxazole/trimethoprim (100%), tetracycline (100%), kanamycin (96.9%), nitrofurantoin (84.4%), ciprofloxacin (68.6%), and chloramphenicol (62.5%) but susceptible to meropenem (100%), colistin (56.3%), and gentamicin (50%). Klebsiella spp. had the highest ESBL occurrence among sick children while E. coli had the highest ESBL occurrence among healthy children in Enugu. All ESBL-positive isolates were multiply resistant to conventional antibiotics. The emergence and spread of β-lactamase-producing Enterobacteriaceae in hospital and community environments highlight the possibility for an infection outbreak if not checked.