General principles of antimicrobial therapy

Effect of probiotics on urinary tract infections in children: A systematic review and meta-analysis

BACKGROUND

Urinary tract infections (UTIs) are the most prevalent bacterial infections that occur in children worldwide.

OBJECTIVE

This meta-analysis aims to investigate the utility of probiotics as preventive therapy in children with a UTI.

METHODS

The Web of Science, PubMed, and Scopus were searched for articles that investigated the relationship between probiotic consumption and the risk of UTIs. The quality of the articles was evaluated using the Jadad scale. The pooled odds ratio (OR) and 95% confidence interval (CI) were calculated using a random-effects model. Subgroup analyses and sensitivity analyses were also conducted. The Cochran Q test and the statistic I2 were used to evaluate heterogeneity. To determine any potential publication bias, the Egger's and Begg's tests were used.

RESULTS

In total, eleven studies were selected for systematic review and meta-analysis. Compared to children who did not receive probiotics, the OR of developing or having a recurring urinary tract infection in those who received probiotics was 0.94 (95% CI; 0.88-0.999; p-value=0.046). The Begg's and Egger's tests showed no evidence of publication bias between probiotics and the risk of developing new or recurring urinary tract infections.

CONCLUSION

Based on this systematic review and meta-analysis, probiotics could be an alternative therapy for children who are at risk of developing a UTI. They are non-pharmaceutical options and could be used as natural prophylaxis for UTIs. However, the currently published evidence does not irrefutably confirm that probiotics provide a protective effect against urinary bacterial infections. Therefore, there need to be large-scale randomized clinical trials undertaken to investigate the possible prophylaxis of probiotics.

Evolution of the murine gut resistome following broad-spectrum antibiotic treatment

The emergence and spread of antimicrobial resistance (AMR) represent an ever-growing healthcare challenge worldwide. Nevertheless, the mechanisms and timescales shaping this resistome remain elusive. Using an antibiotic cocktail administered to a murine model along with a longitudinal sampling strategy, we identify the mechanisms by which gut commensals acquire antimicrobial resistance genes (ARGs) after a single antibiotic course. While most of the resident bacterial populations are depleted due to the treatment, Akkermansia muciniphila and members of the Enterobacteriaceae, Enterococcaceae, and Lactobacillaceae families acquire resistance and remain recalcitrant. We identify specific genes conferring resistance against the antibiotics in the corresponding metagenome-assembled genomes (MAGs) and trace their origins within each genome. Here we show that, while mobile genetic elements (MGEs), including bacteriophages and plasmids, contribute to the spread of ARGs, integrons represent key factors mediating AMR in the antibiotic-treated mice. Our findings suggest that a single course of antibiotics alone may act as the selective sweep driving ARG acquisition and incidence in gut commensals over a single mammalian lifespan.

Antimicrobial resistance represents an ongoing silent pandemic. Here, de Nies et al. show that a single antibiotic treatment leads to resistance in bacteria such as Akkermansia muciniphila and that integrons play a key role in mediating this resistance.

Antibiotics non-adherence and its associated factors among households in southern Ethiopia

Objectives:

This study aimed at assessing the prevalence of antibiotics non-adherence and its associated factor among households in southern Ethiopia.

Methods:

A community-based cross-sectional study was conducted among 323 randomly selected households in Wenago town. To collect the data, structured questionnaire was used. Categorical variables were represented by frequency and percentage. For continuous variables, the mean value and standard deviation were used. Bivariate and multivariate logistic regression analyses were used to identify factors related to antibiotic non-adherence. Finally, for significant factors with p-values less than 0.05, the adjusted odds ratio with 95% confidence interval was calculated and evaluated.

Results:

The prevalence of antibiotic non-adherence in the household was 194 (60.1%) (95% confidence interval = 55.1–65.6). Remission of symptoms (63%) is one of the top reasons for antibiotic non-adherence in the home. Male sex (adjusted odds ratio = 1.77, 95% confidence interval = 1.03–3.08), lower educational status (adjusted odds ratio = 3.42, 95% confidence interval = 1.51–7.75; adjusted odds ratio = 2.37, confidence interval = 1.12–5.02), poor attitude toward antibiotics use (adjusted odds ratio = 1.89; 95% confidence interval = 1.23–3.04), poor knowledge about antibiotics use (adjusted odds ratio = 1.34; 95% confidence interval = 1.11–2.39), and no-prescription information from pharmacy (adjusted odds ratio = 2.02, 95% confidence interval = 1.09–3.72) were all associated with non-adherence. While no medication discomfort (adjusted odds ratio = 0.31, 95% confidence interval = 0.178–0.56) had a negative effect on non-adherence.

Conclusion:

In this study, antibiotic non-adherence was considerably high among the participants. Being male, lower educational status, poor attitude, poor knowledge, no-prescription information from pharmacy/druggist, and medication discomfort were related with antibiotic non-adherence. As a result, community service providers must provide relevant prescription information as well as appropriate counseling to antibiotic non-adherent patients.

Microbiology laboratories involved in disease and antimicrobial resistance surveillance: Strengths and challenges of the central African states

Laboratory systems have been largely neglected on the margins of health systems in Africa. However, since the 2000s, many African countries have benefited from massive investments to strengthen laboratory capacities through projects fighting priority diseases (HIV/AIDS, tuberculosis, malaria). This review examined the laboratory capacities of the Economic Community of Central African States (ECCAS). Online research using specific terms was carried out. Studies published between 2000 and 2021 on the role of the laboratory in disease and antimicrobial resistance surveillance in the 11 ECCAS countries were considered. The number of human and animal health laboratories meeting international standards was very low in the sub-region. There were only seven International Organization for Standardization (ISO) 15189-accredited human health laboratories, with five in Cameroon and two in Rwanda. There were five high biosafety level (BSL) laboratories (one BSL3 laboratory each in Cameroon, the Central African Republic, Democratic Republic of Congo and the Republic of Congo, and one BSL4 laboratory in Gabon) and three ISO 17025-accredited laboratories in the ECCAS sub-region. Only six countries currently have whole-genome sequencing devices, which is insufficient for a sub-region as large and populous as ECCAS. Yet, a plethora of pathogens, particularly haemorrhagic viruses, are endemic in these countries. The need for laboratory capacity strengthening following a One Health approach is imperative. Since emerging and re-emerging zoonotic infectious diseases are projected to triple in frequency over the next 50 years and given the inextricable link between human and animal health, actors in the two health sectors must collaborate to preserve world health.

Systemic Antibiotic Prophylaxis in Maxillofacial Trauma: A Scoping Review and Critical Appraisal

Infection after maxillofacial trauma remains an important complication, with a significant socio-economic impact. While consensus exists that systemic antibiotic prophylaxis reduces the risk of infection in the management of maxillofacial fractures, the type, and duration remain controversial. Therefore, the purpose of this scoping review was to provide an overview of the current evidence that supports the use of prophylactic antibiotics in the treatment of maxillofacial fractures. A comprehensive literature search on 1 January 2022, in PubMed, Web of Science, Embase, and Cochrane, revealed 16 articles. Most studies focused on the duration of systemic antibiotic prophylaxis and compared a one-day to a five-day regimen. Included studies showed considerable variability in design and research aims, which rendered them difficult to compare. Furthermore, a variety of antibiotic regimens were used, and most studies had a short follow-up period and unclear outcome parameters. This scoping review demonstrates the lack of well-constructed studies investigating the type and duration of systemic antibiotic prophylaxis in the treatment of maxillofacial trauma. Based on the included articles, prolonging antibiotic prophylaxis over 24 h for surgically treated fractures does not appear to be beneficial. Furthermore, there is no evidence for its use in conservatively treated fractures. These results should be interpreted with caution since all included studies had limitations.

A Review: Antimicrobial Therapy for Human Pythiosis

Human pythiosis is associated with poor prognosis with significant mortality caused by Pythium insidiosum. Antimicrobials’ in vitro and in vivo results against P. insidiosum are inconsistent. Although antimicrobials are clinically useful, they are not likely to achieve therapeutic success alone without surgery and immunotherapy. New therapeutic options are therefore needed. This non-exhaustive review discusses the rationale antimicrobial therapy, minimum inhibitory concentrations, and efficacy of antibacterial and antifungal agents against P. insidiosum. This review further provides insight into the immunomodulating effects of antimicrobials that can enhance the immune response to infections. Current data support using antimicrobial combination therapy for the pharmacotherapeutic management of human pythiosis. Also, the success or failure of antimicrobial treatment in human pythiosis might depend on the immunomodulatory effects of drugs. The repurposing of existing drugs is a safe strategy for anti-P. insidiosum drug discovery. To improve patient outcomes in pythiosis, we suggest further research and a deeper understanding of P. insidiosum virulence factors, host immune response, and host immune system modification by antimicrobials.

In Vitro Fiber-Probe-Based Identification of Pathogens in Biofilms by Raman Spectroscopy

Biofilms are the preferred habitat of microorganisms on living and artificial surfaces. Biofilm-related infections, such as infections of medical implants, are difficult to treat, and due to a reduced cultivability of the included bacteria, difficult to diagnose. Therefore, it is highly important to rapidly identify and investigate biofilms on implant surfaces, e.g., during surgery. In this study, we present fiber-probe-based Raman spectroscopy with an excitation wavelength of 785 nm, which was applied to investigate six different pathogen species involved in biofilm-related infections. Biofilms were cultivated in a drip flow reactor, which can model a biofilm growth environment. The signals collected from a fiber probe allowed us to collect Raman spectra not only from the embedded bacterial and yeast cells but also the surrounding extracellular polymeric substance matrix. This information was used in a classification model. The model consists of a principal component analysis in combination with linear discriminant analysis and was examined by applying a leave-one-batch-out cross-validation. This model achieved a classification accuracy of 93.8%. In addition, the identification accuracy increased up to 97.5% when clinical strains were used for identification. A fiber-probe-based Raman spectroscopy method combined with a chemometric analysis might therefore serve as a fast, accurate, and portable strategy for the species identification of biofilm-related infections, e.g., during surgical procedures.

Emerging nanotechnologies for targeting antimicrobial resistance

Antimicrobial resistance is a leading cause of mortality worldwide. Without newly approved antibiotics and antifungals being brought to the market, resistance is being developed to the ones currently available to clinicians. The reason is the applied evolutionary pressure to bacterial and fungal species due to the wide overuse of common antibiotics and antifungals in clinical practice and agriculture. Biofilms harbour antimicrobial-resistant subpopulations, which make their antimicrobial treatment even more challenging. Nanoparticle-based technologies have recently been shown to successfully overcome antimicrobial resistance in both planktonic and biofilms phenotypes. This results from the combination of novel nanomaterial research and classic antimicrobial therapies which promise to deliver a whole new generation of high-performance active nanocarrier systems. This review discusses the latest developments of promising nanotechnologies with applications against resistant pathogens and evaluates their potential and feasibility for use in novel antimicrobial therapies.

Dose Selection for Phase III Clinical Evaluation of Gepotidacin (GSK2140944) in the Treatment of Uncomplicated Urinary Tract Infections

Antibiotics are the current standard-of-care treatment for uncomplicated urinary tract infections (uUTIs). However, increasing rates of bacterial antibiotic resistance necessitate novel therapeutic options. Gepotidacin is a first-in-class triazaacenaphthylene antibiotic that selectively inhibits bacterial DNA replication by interaction with the bacterial subunits of DNA gyrase (GyrA) and topoisomerase IV (ParC). Gepotidacin is currently in clinical development for the treatment of uUTIs and other infections. In this article, we review data for gepotidacin from nonclinical studies, including in vitro activity, in vivo animal efficacy, and pharmacokinetic (PK) and pharmacokinetic/pharmacodynamic (PK/PD) models that informed dose selection for phase III clinical evaluation of gepotidacin. Based on this translational package of data, a gepotidacin 1,500-mg oral dose twice daily for 5 days was selected for two ongoing, randomized, multicenter, parallel-group, double-blind, double-dummy, active-comparator phase III clinical studies evaluating the safety and efficacy of gepotidacin in adolescent and adult female participants with uUTIs (ClinicalTrials.gov identifiers NCT04020341 and NCT04187144).

The Use of Antibody-Antibiotic Conjugates to Fight Bacterial Infections

The emergence of antimicrobial resistance (AMR) is rapidly increasing and it is one of the significant twenty-first century's healthcare challenges. Unfortunately, the development of effective antimicrobial agents is a much slower and complex process compared to the spread of AMR. Consequently, the current options in the treatment of AMR are limited. One of the main alternatives to conventional antibiotics is the use of antibody-antibiotic conjugates (AACs). These innovative bioengineered agents take advantage of the selectivity, favorable pharmacokinetic (PK), and safety of antibodies, allowing the administration of more potent antibiotics with less off-target effects. Although AACs' development is challenging due to the complexity of the three components, namely, the antibody, the antibiotic, and the linker, some successful examples are currently under clinical studies.

Mass Spectrometry-Based Detection of Beta Lactam Hydrolysis Enables Rapid Detection of Beta Lactamase Mediated Antibiotic Resistance

OBJECTIVE

Antibiotic resistance by beta lactamase expression is a serious and growing threat. We aimed to determine whether beta-lactamase activity is detectable in urine specimens to enable faster identification of resistance.

METHODS

Urine specimens from patients with extended spectrum beta lactamase (ESBL)-expressing urinary infections were incubated with beta lactam antibiotics. Beta lactam hydrolysis was determined by mass spectrometry methods.

RESULTS

Ceftriaxone hydrolysis was observed in 45 of 45 ESBL-containing specimens from patients not treated with a beta lactamase inhibitor before specimen collection. Ceftriaxone hydrolysis was not observed in 108 of 108 non-ESBL-containing specimens. Spiking studies show that beta lactam hydrolysis can be observed within 30 minutes. Beta lactam hydrolysis is evidenced by mass spectrometry preceded by either liquid chromatography or matrix-assisted laser desorption ionization specimen processing methods.

CONCLUSION

Clinically significant beta lactamase activity is detectable directly from urine specimens. The described methods would enable the detection of beta lactam resistance 24 to 48 hours sooner than culture based methods.

Optimizing Nanopore Sequencing for Rapid Detection of Microbial Species and Antimicrobial Resistance in Patients at Risk of Surgical Site Infections

Surgical site infections (SSI) are a significant burden to patients and health care systems. We evaluated the use of Nanopore sequencing (NS) to rapidly detect microbial species and antimicrobial resistance (AMR) genes present in intraoperative bile aspirates. Bile aspirates from 42 patients undergoing pancreatic head resection were included. Three methods of DNA extraction using mechanical cell lysis or protease cell lysis were compared to determine the optimum method of DNA extraction. The impact of host DNA depletion, sequence run duration, and use of different AMR gene databases was also assessed. To determine clinical value, NS results were compared to standard culture (SC) results. NS identified microbial species in all culture positive samples. Mechanical lysis improved NS detection of cultured species from 60% to 76%, enabled detection of fungal species, and increased AMR predictions. Host DNA depletion improved detection of streptococcal species and AMR correlation with SC. Selection of AMR database influenced the number of AMR hits and resistance profile of 13 antibiotics. AMR prediction using CARD and ResFinder 4.1 correctly predicted 79% and 81% of the bile antibiogram, respectively. Sequence run duration positively correlated with detection of AMR genes. A minimum of 6 h was required to characterize the biliary microbes, resulting in a turnaround time of 14 h. Rapid identification of microbial species and AMR genes can be achieved by NS. NS results correlated with SC, suggesting that NS may be useful in guiding early antimicrobial therapy postsurgery. IMPORTANCE Surgical site infections (SSI) are a significant burden to patients and health care systems. They increase mortality rates, length of hospital stays, and associated health care costs. To reduce the risk of SSI, surgical patients are administered broad-spectrum antibiotics that are later adapted to target microbial species detected at the site of surgical incision. Use of broad-spectrum antibiotics can be harmful to the patient. We wanted to develop a rapid method of detecting microbial species and their antimicrobial resistance phenotypes. We developed a method of detecting microbial species and predicting resistance phenotypes using Nanopore sequencing. Results generated using Nanopore sequencing were similar to current methods of detection but were obtained in a significantly shorter amount of time. This suggests that Nanopore sequencing could be used to tailor antibiotics in surgical patients and reduce use of broad-spectrum antibiotics.

Rapid Antimicrobial Susceptibility Testing by Stimulated Raman Scattering Imaging of Deuterium Incorporation in a Single Bacterium

To slow and prevent the spread of antimicrobial resistant infections, rapid antimicrobial susceptibility testing (AST) is in urgent need to quantitatively determine the antimicrobial effects on pathogens. It typically takes days to complete the AST by conventional methods based on the long-time culture, and they do not work directly for clinical samples. Here, we report a rapid AST method enabled by stimulated Raman scattering (SRS) imaging of deuterium oxide (D2O) metabolic incorporation. Metabolic incorporation of D2O into biomass and the metabolic activity inhibition upon exposure to antibiotics at the single bacterium level are monitored by SRS imaging. The single-cell metabolism inactivation concentration (SC-MIC) of bacteria upon exposure to antibiotics can be obtained after a total of 2.5 h of sample preparation and detection. Furthermore, this rapid AST method is directly applicable to bacterial samples in complex biological environments, such as urine or whole blood. SRS metabolic imaging of deuterium incorporation is transformative for rapid single-cell phenotypic AST in the clinic.

Diagnosis and Treatment of Helicobacter pylori Infection

The last 5 years have seen major shifts in defining whom to test and how to treat Helicobacter pylori infection. Peptic ulcer has changed from a chronic disease to a one-off condition, and countries with a high incidence of gastric cancer have begun implementing population-wide screening and treatment. A proactive approach to testing and treatment of H. pylori is now recommended, including outreach to family members of individuals diagnosed with active infection as well as high-risk local populations such as immigrants from high-risk countries. Increasing antimicrobial resistance has resulted in an overall decline in treatment success, causing a rethinking of the approach to development of treatment guidelines as well as the need to adopt the principles of antibiotic usage and antimicrobial stewardship. Required changes include abandoning empiric use of clarithromycin, metronidazole, and levofloxacin triple therapies. Here, we discuss these transformations and give guidance regarding testing and use of therapies that are effective when given empirically.

Prescribing practices for presumptive TB among private general practitioners in South Africa: a cross-sectional, standardised patient study

Introduction

Medicine prescribing practices are integral to quality of care for leading infectious diseases such as tuberculosis (TB). We describe prescribing practices in South Africa’s private health sector, where an estimated third of people with TB symptoms first seek care.

Methods

Sixteen standardised patients (SPs) presented one of three cases during unannounced visits to private general practitioners (GPs) in Durban and Cape Town: TB symptoms, HIV-positive; TB symptoms, a positive molecular test for TB, HIV-negative; and TB symptoms, history of incomplete TB treatment, HIV-positive. Prescribing practices were recorded in standardised exit interviews and analysed based on their potential to contribute to negative outcomes, including increased healthcare expenditures, antibiotic overuse or misuse, and TB diagnostic delay. Factors associated with antibiotic use were assessed using Poisson regression with a robust variance estimator.

Results

Between August 2018 and July 2019, 511 SP visits were completed with 212 GPs. In 88.5% (95% CI 85.2% to 91.1%) of visits, at least one medicine (median 3) was dispensed or prescribed and most (93%) were directly dispensed. Antibiotics, which can contribute to TB diagnostic delay, were the most common medicine (76.5%, 95% CI 71.7% to 80.7% of all visits). A majority (86.1%, 95% CI 82.9% to 88.5%) belonged to the WHO Access group; fluoroquinolones made up 8.8% (95% CI 6.3% to 12.3%). Factors associated with antibiotic use included if the SP was asked to follow-up if symptoms persisted (RR 1.14, 95% CI 1.04 to 1.25) and if the SP presented as HIV-positive (RR 1.11, 95% CI 1.01 to 1.23). An injection was offered in 31.9% (95% CI 27.0% to 37.2%) of visits; 92% were unexplained. Most (61.8%, 95% CI 60.2% to 63.3%) medicines were not listed on the South African Primary Healthcare Essential Medicines List.

Conclusion

Prescribing practices among private GPs for persons presenting with TB-like symptoms in South Africa raise concern about inappropriate antimicrobial use, private healthcare costs and TB diagnostic delay.

Prevalence and characterization of antimicrobial resistance among gram-negative bacteria isolated from febrile hospitalized patients in central Ethiopia

BACKGROUND

Infectious diseases are among the leading causes of death in many low-income countries, such as Ethiopia. Without reliable local data concerning causative pathogens and antimicrobial resistance, empiric treatment is suboptimal. The objective of this study was to characterize gram-negative bacteria (GNB) as pathogens and their resistance pattern in hospitalized patients with infections in central Ethiopia.

METHODS

Patients ≥ 1 year of age with fever admitted to the Asella Referral and Teaching Hospital from April 2016 to June 2018 were included. Blood and other appropriate clinical specimens were collected and cultured on appropriate media. Antibiotic susceptibility testing (AST) was performed using the Kirby-Bauer method and VITEK® 2. Species identification and detection of resistance genes were conducted using MALDI-ToF MS (VITEK® MS) and PCR, respectively.

RESULTS

Among the 684 study participants, 54.2% were male, and the median age was 22.0 (IQR: 14-35) years. Blood cultures were positive in 5.4% (n = 37) of cases. Among other clinical samples, 60.6% (20/33), 20.8% (5/24), and 37.5% (3/8) of swabs/pus, urine and other body fluid cultures, respectively, were positive. Among 66 pathogenic isolates, 57.6% (n = 38) were GNB, 39.4% (n = 26) were gram-positive, and 3.0% (n = 2) were Candida species. Among the isolated GNB, 42.1% (16/38) were Escherichia coli, 23.7% (9/38) Klebsiella pneumoniae and 10.5% (4/38) Pseudomonas aeruginosa. In total, 27/38 gram-negative isolates were available for further analysis. Resistance rates were as follows: ampicillin/sulbactam, 92.6% (n = 25); cefotaxime, 88.9% (n = 24); ceftazidime, 74.1% (n = 20); cefepime, 74.1% (n = 20); gentamicin, 55.6% (n = 15); piperacillin/tazobactam, 48.1% (n = 13); meropenem, 7.4% (n = 2); and amikacin, 3.7% (n = 1). The bla_NDM-1 gene was detected in one K. pneumoniae and one Acinetobacter baumannii isolate, which carried an additional bla_OXA-51 gene. The ESBL enzymes were detected in 81.5% (n = 22) of isolates as follows: TEM, 77.2% (n = 17); CTX-M-1 group, 68.2% (n = 15); SHV group, 27.3% (n = 6); and CTX-M-9 group, 9.1% (n = 2). Based on the in vitro antimicrobial susceptibility results, empiric treatment initiated in 13 of 18 (72.2%) patients was likely ineffective.

CONCLUSION

We report a high prevalence of ESBL-producing bacteria (81.5%) and carbapenem resistance (7.4%), with more than half of GNB carrying two or more ESBL enzymes resulting in suboptimal empiric antibiotic therapy. These findings indicate a need for local and national antimicrobial resistance surveillance and the strengthening of antimicrobial stewardship programs.

Isolation and characterisation of antibacterial and anti-inflammatory compounds from Gnaphalium polycaulon

ETHNO-PHARMACOLOGICAL RELEVANCE

Gnaphalium polycaulon commonly known as "cudweed" has been used throughout South America as an infusion to treat colds, bronchitis, fever or pneumonia.

AIM OF THE STUDY

This study aimed to determine the antibacterial and anti-inflammatory activities of the aqueous extract of Gnaphalium polycaulon and identify the related compounds.

MATERIALS AND METHODS

A bio-guided isolation of the active compounds of Gnaphalium polycaulon was carried out, selecting the fractions depending on their antibacterial, anti-inflammatory and cytotoxic activities. The antibacterial effect was studied against Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus and Streptococcus pneumoniae; and the anti-inflammatory study was performed by measuring the inhibition of NF-κB in BEAS-2B and IMR-90 cell cultures.

RESULTS

Three compounds were obtained and characterised by nuclear magnetic resonance and mass spectrometry. These compounds are 2-(4-(1-H-tetrazol-1-yl) phenyl)-2-aminopropanoic acid (1), N-phenyl-4-(3-phenyl-1,2,4-thiadiazol-5-yl) piperazine-1-carboxamide (2) and N-(4-ethoxyphenyl)-4-(2-methylimidazo-[1,2-α] pyridine-3-yl) thiazol-2-amine (3). All compounds showed antibacterial activity with MIC values of 44.80-44.85, 0.017-0.021 and 0.0077-0.0079 μM, respectively, in the Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus and Streptococcus pneumoniae strains, while the positive control, Ofloxacin, had a MIC value of 27.64-27.67 μM. This was corroborated through a zone inhibition assay, where compound 3 (11.36-11.67 mm) was much more active than the positive control (Ofloxacin, 23.41-24.12 mm), while compounds 2 (26.47-27.64 mm) and 1 (28.39-29.76 mm) displayed similar antibacterial potential to the positive control. Finally, all the compounds presented NF-κB inhibitory activity, compounds 3 (IC₅₀ = 0.0071-0.0073 μM) and 2 (IC₅₀ = 0.016-0.019 μM) being the most promising. Compound 1 (IC₅₀ = 44.24-44.26 μM) had less anti-inflammatory potential, being also the closest to the values displayed by the positive control (Celastrol, IC₅₀ = 7.41 μM).

CONCLUSION

In the present study, three compounds were isolated for the first time from the aqueous extract of Gnaphalium polycaulon. Their antibacterial and anti-inflammatory potential was tested and showcased.

Mesenchymal Stem Cell-Derived Exosome Therapy of Microbial Diseases: From Bench to Bed

Microbial diseases are a global health threat, leading to tremendous casualties and economic losses. The strategy to treat microbial diseases falls into two broad categories: pathogen-directed therapy (PDT) and host-directed therapy (HDT). As the typical PDT, antibiotics or antiviral drugs directly attack bacteria or viruses through discerning specific molecules. However, drug abuse could result in antimicrobial resistance and increase infectious disease morbidity. Recently, the exosome therapy, as a HDT, has attracted extensive attentions for its potential in limiting infectious complications and targeted drug delivery. Mesenchymal stem cell-derived exosomes (MSC-Exos) are the most broadly investigated. In this review, we mainly focus on the development and recent advances of the application of MSC-Exos on microbial diseases. The review starts with the difficulties and current strategies in antimicrobial treatments, followed by a comprehensive overview of exosomes in aspect of isolation, identification, contents, and applications. Then, the underlying mechanisms of the MSC-Exo therapy in microbial diseases are discussed in depth, mainly including immunomodulation, repression of excessive inflammation, and promotion of tissue regeneration. In addition, we highlight the latest progress in the clinical translation of the MSC-Exo therapy, by summarizing related clinical trials, routes of administration, and exosome modifications. This review will provide fundamental insights and future perspectives on MSC-Exo therapy in microbial diseases from bench to bedside.

Mapping of New Pharmacological Alternatives in the Face of the Emergence of Antibiotic Resistance in COVID-19 Patents Treated for Opportunistic Respiratory Bacterial Pathogens

BACKGROUND

The increase in bacterial resistance against antibiotics is thought to be another type of pandemic after COVID-19. Emergency treatment based on antibiotics is a major influence in increasing this resistance. Bacteria, such as Klebsiella pneumoniae, are the most affected by the indiscriminate use of antibiotics, since they are resistant to most antibiotics currently available on the market.

OBJECTIVE

This review aimed to evaluate patents of new drugs and formulations, for the treatment of infections caused by Klebsiella pneumoniae.

METHODS

The present patent review was carried out through a specialized search database Espacenet. The selection was based on the criteria of patents published from 2010 to May 2021, in any language, and containing the keywords in title or abstract. Also, a research was performed on the PubMed database, using the inclusion criteria.

RESULTS

Twenty-two patents were selected for the analysis according to the aim of the study. The advance of new patents has been mostly observed in the World Intellectual Property Organization, China, and United States. The results showed that the main approach was the drug association, followed by drug carriers, new isolated products, and vaccines.

CONCLUSION

It has been observed that few studies use new drug alternatives for the treatment, probably due to the higher cost of the development and lack of investments. The effectiveness and safety of these therapies depend on the acceptance, the correct prescription, and rational use of medicines. Therefore, this review can further develop new treatments as alternatives against Klebsiella pneumoniae and pneumonia caused by it.

Patterns of Antimicrobial Use in an Outpatient Hemodialysis Unit

BACKGROUND

Patients receiving hemodialysis (HD) are at high risk of infections, including those caused by multidrug-resistant organisms. Given that antimicrobial exposure is a major risk factor for the emergence of these resistant organisms, minimizing inappropriate use is imperative. To optimize use, it is important to understand patterns of antimicrobial prescribing in this setting.

OBJECTIVES

To measure antimicrobial use and to describe prescribing patterns among patients receiving outpatient HD.

METHODS

A retrospective observational case series study was performed in an outpatient HD unit from February to April 2017. Adults for whom at least 1 antimicrobial was prescribed were included. The primary outcome was total antimicrobial days of therapy (DOT) per 1000 patient-days. Secondary outcomes were the characteristics of the antimicrobial prescriptions, in terms of antimicrobial class, indication, purpose, route, and prescriber group.

RESULTS

Antimicrobials were prescribed for 53 (16%) of the 330 patients treated in the HD unit during the study period; the total number of prescriptions was 75. Antimicrobial use was 27.5 DOTs/1000 patient-days. Fluoroquinolones were the most frequently prescribed type of antimicrobial (n = 17, 23%), whereas the second most frequently prescribed were first-generation cephalosporins (n = 16, 21%). The most common indication was skin or soft-tissue infection (n = 14, 19%), followed by bloodstream infection (n = 13, 17%). Of the 75 antimicrobials, 48 (64%) were prescribed for empiric therapy, 19 (25%) for targeted therapy, and 8 (11%) for prophylaxis. Two-thirds of the antimicrobials prescribed (n = 50, 67%) were oral medications, and most (n = 72, 96%) were ordered by hospital prescribers.

CONCLUSIONS

Antimicrobial use was common in this study setting, with 1 in 6 HD patients receiving this type of medication. The findings of this study create opportunities to standardize antimicrobial prescribing at the local level for common infections that occur in patients receiving outpatient HD.

Antimicrobial Sensitivity Pattern from Hospitalized Pneumonia Patients in National Referral Infectious Disease Hospital in Indonesia

BACKGROUND

Pneumonia is still a major global problem with high morbidity and mortality. The increasing number of pneumonia cases caused by bacteria, especially multidrug-resistant pathogens, increasing age of the population, patients with chronic disease (comorbid), and inappropriate antimicrobial therapy at initial administration make the treatment become less effective. These issues finally contribute to higher morbidity and mortality in cases of hospitalized pneumonia patients. Therefore, it is crucial to know the microbial pattern and select the therapy according to local antimicrobial sensitivity patterns.

METHOD

A cross-sectional study was conducted for hospitalized pneumonia patients between January 2015 and December 2016 in Indonesia National Referral Infectious Disease Hospital. Data were collected from medical records to show patient characteristics, antimicrobial treatment data, culture examination, and bacterial sensitivity.

RESULTS

A total of 99 pneumonia patients required hospitalization and underwent sputum culture examination. The patients were mostly above 65 years old (32.3%) and male (57.6%). The most common comorbidities were pulmonary tuberculosis (21%), and the others were heart failure, chronic obstructive pulmonary disease (COPD), and HIV/AIDS. Based on the sputum culture, fungi were identified in most specimens (56%), while the bacteria identified were Klebsiella pneumoniae (14%), Acinetobacter sp. (12%), and Pseudomonas sp. (8%). Third-generation cephalosporin, such as ceftriaxone (50%), was commonly used as an antibiotic for pneumonia treatment.

CONCLUSION

Most common bacteria isolated from sputum culture were Klebsiella pneumoniae which were more sensitive to the beta-lactam and aminoglycoside groups. The higher risk factors were age above 65 years old, being male, and having tuberculosis.

The war against bacteria, from the past to present and beyond

INTRODUCTION

The human defense against microorganisms dates back to the ancient civilizations, with attempts to use substances from vegetal, animal, or inorganic origin to fight infections. Today, the emerging threat of multidrug-resistant bacteria highlights the consequences of antibiotics inappropriate use, and the urgent need for novel effective molecules.

METHODS AND MATERIALS

We extensively researched on more recent data within PubMed, Medline, Web of Science, Elsevier's EMBASE, Cochrane Review for the modern pharmacology in between 1987 - 2021. The historical evolution included a detailed analysis of past studies on the significance of medical applications in the ancient therapeutic field.

AREAS COVERED

We examined the history of antibiotics development and discovery, the most relevant biochemical aspects of their mode of action, and the biomolecular mechanisms conferring bacterial resistance to antibiotics.

EXPERT OPINION

The list of pathogens showing low sensitivity or full resistance to most currently available antibiotics is growing worldwide. Long after the 'golden age' of antibiotic discovery, the most novel molecules should be carefully reserved to treat serious bacterial infections of susceptible bacteria. A correct diagnostic and therapeutic procedure can slow down the spreading of nosocomial and community infections sustained by multidrug-resistant bacterial strains.

Prevalence and Antimicrobial Resistance of Enterococcus Species: A Retrospective Cohort Study in Italy

Antimicrobial resistance represents one of the main threats to healthy ecosystems. In recent years, among the multidrug-resistant microorganisms responsible for nosocomial infections, the Enterococcus species have received much attention. Indeed, Enterococcus have peculiar skills in their ability to acquire resistance genes and to cause severe diseases, such as endocarditis. This study showed the prevalence and antimicrobial resistance rate of Enterococcus spp. isolated from clinical samples, from January 2015 to December 2019 at the University Hospital "San Giovanni di Dio e Ruggi d'Aragona" in Salerno, Italy. A total of 3236 isolates of Enterococcus faecalis (82.2%) and Enterococcus faecium (17.8%) were collected from urine cultures, blood cultures, catheters, respiratory tract, and other samples. Bacterial identification and antibiotic susceptibility were performed with VITEK 2. E. faecium showed a high resistance rate against ampicillin (84.5%), ampicillin/sulbactam (82.7%), and imipenem (86.7%), while E. faecalis showed the highest resistance rate against gentamicin and streptomycin high level, but both were highly sensitive to such antibiotics as tigecycline and vancomycin. Studies of surveillance are an important tool to detect changes in the resistance profiles of the main pathogens. These antimicrobial susceptibility patterns are necessary to improve the empirical treatment guideline of infections.

Melt-extrusion 3D printing of resorbable levofloxacin-loaded meshes: Emerging strategy for urogynaecological applications

Current surgical strategies for the treatment of pelvic floor dysfunctions involve the placement of a polypropylene mesh into the pelvic cavity. However, polypropylene meshes have proven to have inadequate mechanical properties and have been associated to the arising of severe complications, such as infections. Furthermore, currently employed manufacturing strategies are unable to produce compliant and customisable devices. In this work, polycaprolactone has been used to produce resorbable levofloxacin-loaded meshes in two different designs (90° and 45°) via melt-extrusion 3D printing. Drug-loaded meshes were produced using a levofloxacin concentration of 0.5% w/w. Drug loaded meshes were successfully produced with highly reproducible mechanical and physico-chemical properties. Tensile test results showed that drug-loaded 45° meshes possessed a mechanical behaviour close to that of the vaginal tissue (E ≃ 8.32 ± 1.85 MPa), even after 4 weeks of accelerated degradation. Meshes released 80% of the loaded levofloxacin in the first 3 days and were capable of producing an inhibitory effect against S. Aureus and E. coli bacterial strains with an inhibition zone equal to 12.8 ± 0.45 mm and 15.8 ± 0.45 mm respectively. Thus, the strategy adopted in this work holds great promise for the manufacturing of custom-made surgical meshes with antibacterial properties.

Phage therapeutics: from promises to practices and prospectives

The rise in multi-drug resistant bacteria and the inability to develop novel antibacterial agents limits our arsenal against infectious diseases. Antibiotic resistance is a global issue requiring an immediate solution, including the development of new antibiotic molecules and other alternative modes of therapy. This article highlights the mechanism of bacteriophage treatment that makes it a real solution for multidrug-resistant infectious diseases. Several case reports identified phage therapy as a potential solution to the emerging challenge of multi-drug resistance. Bacteriophages, unlike antibiotics, have special features, such as host specificity and do not impact other commensals. A new outlook has also arisen with recent advancements in the understanding of phage immunobiology, where phages are repurposed against both bacterial and viral infections. Thus, the potential possibility of phages in COVID-19 patients with secondary bacterial infections has been briefly elucidated. However, significant obstacles that need to be addressed are to design better clinical studies that may contribute to the widespread use of bacteriophage therapy against multi-drug resistant pathogens. In conclusion, antibacterial agents can be used with bacteriophages, i.e. bacteriophage-antibiotic combination therapy, or they can be administered alone in cases when antibiotics are ineffective.Key points• AMR, a consequence of antibiotic generated menace globally, has led to the resurgence of phage therapy as an effective and sustainable solution without any side effects and high specificity against refractory MDR bacterial infections.• Bacteriophages have fewer adverse reactions and can thus be used as monotherapy as well as in conjunction with antibiotics.• In the context of the COVID-19 pandemic, phage therapy may be a viable option.

Prevention, Diagnosis and Management of Post-Surgical Mediastinitis in Adults Consensus Guidelines of the Spanish Society of Cardiovascular Infections (SEICAV), the Spanish Society of Thoracic and Cardiovascular Surgery (SECTCV) and the Biomedical Research Centre Network for Respiratory Diseases (CIBERES)

This is a consensus document of the Spanish Society of Cardiovascular Infections (SEICAV), the Spanish Society of Thoracic and Cardiovascular Surgery (SECTCV) and the Biomedical Research Centre Network for Respiratory Diseases (CIBERES). These three entities have brought together a multidisciplinary group of experts that includes anaesthesiologists, cardiac and cardiothoracic surgeons, clinical microbiologists, infectious diseases and intensive care specialists, internal medicine doctors and radiologists. Despite the clinical and economic consequences of sternal wound infections, to date, there are no specific guidelines for the prevention, diagnosis and management of mediastinitis based on a multidisciplinary consensus. The purpose of the present document is to provide evidence-based guidance on the most effective diagnosis and management of patients who have experienced or are at risk of developing a post-surgical mediastinitis infection in order to optimise patient outcomes and the process of care. The intended users of the document are health care providers who help patients make decisions regarding their treatment, aiming to optimise the benefits and minimise any harm as well as the workload.

Membrane bioreactors for hospital wastewater treatment: recent advancements in membranes and processes

Discharged hospital wastewater contains various pathogenic microorganisms, antibiotic groups, toxic organic compounds, radioactive elements, and ionic pollutants. These contaminants harm the environment and human health causing the spread of disease. Thus, effective treatment of hospital wastewater is an urgent task for sustainable development. Membranes, with controllable porous and nonporous structures, have been rapidly developed for molecular separations. In particular, membrane bioreactor (MBR) technology demonstrated high removal efficiency toward organic compounds and low waste sludge production. To further enhance the separation efficiency and achieve material recovery from hospital waste streams, novel concepts of MBRs and their applications are rapidly evolved through hybridizing novel membranes (non hydrophilic ultrafiltration/microfiltration) into the MBR units (hybrid MBRs) or the MBR as a pretreatment step and integrating other membrane processes as subsequent secondary purification step (integrated MBR-membrane systems). However, there is a lack of reviews on the latest advancement in MBR technologies for hospital wastewater treatment, and analysis on its major challenges and future trends. This review started with an overview of main pollutants in common hospital waste-water, followed by an understanding on the key performance indicators/criteria in MBR membranes (i.e., solute selectivity) and processes (e.g., fouling). Then, an in-depth analysis was provided into the recent development of hybrid MBR and integrated MBR-membrane system concepts, and applications correlated with wastewater sources, with a particular focus on hospital wastewaters. It is anticipated that this review will shed light on the knowledge gaps in the field, highlighting the potential contribution of hybrid MBRs and integrated MBR-membrane systems toward global epidemic prevention.

PBPK Modeling and Simulation and Therapeutic Drug Monitoring: Possible Ways for Antibiotic Dose Adjustment

Pharmacokinetics (PK) is a branch of pharmacology present and of vital importance for the research and development (R&D) of new drugs, post-market monitoring, and continued optimizations in clinical contexts. Ultimately, pharmacokinetics can contribute to improving patients’ clinical outcomes, helping enhance the efficacy of treatments, and reducing possible adverse side effects while also contributing to precision medicine. This article discusses the methods used to predict and study human pharmacokinetics and their evolution to the current physiologically based pharmacokinetic (PBPK) modeling and simulation methods. The importance of therapeutic drug monitoring (TDM) and PBPK as valuable tools for Model-Informed Precision Dosing (MIPD) are highlighted, with particular emphasis on antibiotic therapy since dosage adjustment of antibiotics can be vital to ensure successful clinical outcomes and to prevent the spread of resistant bacterial strains.

Friends or Foes? Rapid Determination of Dissimilar Colistin and Ciprofloxacin Antagonism of Pseudomonas aeruginosa Phages

Phage therapy is a century-old technique employing viruses (phages) to treat bacterial infections, and in the clinic it is often used in combination with antibiotics. Antibiotics, however, interfere with critical bacterial metabolic activities that can be required by phages. Explicit testing of antibiotic antagonism of phage infection activities, though, is not a common feature of phage therapy studies. Here we use optical density-based 'lysis-profile' assays to assess the impact of two antibiotics, colistin and ciprofloxacin, on the bactericidal, bacteriolytic, and new-virion-production activities of three Pseudomonas aeruginosa phages. Though phages and antibiotics in combination are more potent in killing P. aeruginosa than either acting alone, colistin nevertheless substantially interferes with phage bacteriolytic and virion-production activities even at its minimum inhibitory concentration (1× MIC). Ciprofloxacin, by contrast, has little anti-phage impact at 1× or 3× MIC. We corroborate these results with more traditional measures, particularly colony-forming units, plaque-forming units, and one-step growth experiments. Our results suggest that ciprofloxacin could be useful as a concurrent phage therapy co-treatment especially when phage replication is required for treatment success. Lysis-profile assays also appear to be useful, fast, and high-throughput means of assessing antibiotic antagonism of phage infection activities.

Effect of Obesity on Clinical Outcomes of Patients Treated With Cefepime

Background: As the prevalence of obesity climbs, dosing of antimicrobials, particularly cephalosporins, is becoming a greater challenge for clinicians. Data are lacking for appropriate dosing of cefepime, an anti-pseudomonal cephalosporin that is widely used as an empiric anti-pseudomonal agent. Objective: The purpose of this study was to determine the rate of clinical treatment failure in obese patients compared with nonobese patients receiving cefepime as definitive monotherapy. Methods: Adult inpatients treated with cefepime monotherapy for ≥72 hours were included. Patients were excluded if they (1) were not able to achieve culture clearance within 72 hours and (2) had polymicrobial infections requiring more than one antibiotic for definitive therapy. Results: Fifty-eight obese patients and 56 nonobese patients were included. Pseudomonas aeruginosa, Escherichia coli, and Enterobacter spp were the most prevalent organisms isolated. Most organisms had a minimum inhibitory concentration of ≤1 µg/mL to cefepime with no differences in minimum inhibitory concentration distributions between groups. Definitively, 60% of patients received cefepime 1 g, while almost 40% received cefepime 2 g. Clinical failure occurred in 52% of patients (67% obese vs 36% nonobese; P = .001), with study group (odds ratio = 1.057, 95% confidence interval = 1.008-1.109) and respiratory source (odds ratio = 3.251, 95% confidence interval = 1.378-7.667) being independent predictors of failure. There were no differences in hospital length of stay, all-cause mortality, or 30-day readmissions. Conclusions: Obese patients treated with cefepime are more likely to experience treatment failure than nonobese patients. Larger trials examining the reasons for clinical failure in obese patients treated with cefepime are needed to confirm the findings from this preliminary work.

Carbon Nanomaterials Modified Biomimetic Dental Implants for Diabetic Patients

Dental implants are used broadly in dental clinics as the most natural-looking restoration option for replacing missing or highly diseased teeth. However, dental implant failure is a crucial issue for diabetic patients in need of dentition restoration, particularly when a lack of osseointegration and immunoregulatory incompetency occur during the healing phase, resulting in infection and fibrous encapsulation. Bio-inspired or biomimetic materials, which can mimic the characteristics of natural elements, are being investigated for use in the implant industry. This review discusses different biomimetic dental implants in terms of structural changes that enable antibacterial properties, drug delivery, immunomodulation, and osseointegration. We subsequently summarize the modification of dental implants for diabetes patients utilizing carbon nanomaterials, which have been recently found to improve the characteristics of biomimetic dental implants, including through antibacterial and anti-inflammatory capabilities, and by offering drug delivery properties that are essential for the success of dental implants.

Comparison of Culture With Antibiogram to Next-Generation Sequencing Using Bacterial Isolates and Formalin-Fixed, Paraffin-Embedded Gastric Biopsies

BACKGROUND & AIMS

The decline in Helicobacter pylori cure rates emphasizes the need for readily available methods to determine antimicrobial susceptibility. Our aim was to compare targeted next-generation sequencing (NGS) and culture-based H pylori susceptibility testing using clinical isolates and paired formalin-fixed, paraffin-embedded (FFPE) gastric biopsies.

METHODS

H pylori isolates and FFPE tissues were tested for susceptibility to amoxicillin, clarithromycin, metronidazole, levofloxacin, tetracycline, and rifabutin using agar dilution and NGS targeted to 23S rRNA, gyrA, 16S rRNA, pbp1, rpoB and rdxA. Agreement was quantified using κ statistics.

RESULTS

Paired comparisons included 170 isolates and FFPE tissue for amoxicillin, clarithromycin, metronidazole, and rifabutin and 57 isolates and FFPE tissue for levofloxacin and tetracycline. Agreement between agar dilution and NGS from culture isolates was very good for clarithromycin (κ = 0.90012), good for levofloxacin (κ = 0.78161) and fair for metronidazole (κ = 0.55880), and amoxicillin (κ = 0.21400). Only 1 isolate was resistant to tetracycline (culture) and 1 to rifabutin (NGS). Comparison of NGS from tissue blocks and agar dilution from isolates from the same stomachs demonstrated good accuracy to predict resistance for clarithromycin (94.1%), amoxicillin (95.9%), metronidazole (77%), levofloxacin (87.7%), and tetracycline (98.2%). Lack of resistance precluded comparisons for tetracycline and rifabutin.

CONCLUSIONS

Compared with agar dilution, NGS reliably determined resistance to clarithromycin, levofloxacin, rifabutin, and tetracycline from clinical isolates and formalin-fixed gastric tissue. Consistency was fair for metronidazole and amoxicillin. Culture-based testing can predict treatment outcomes with clarithromycin and levofloxacin. Studies are needed to compare the relative ability of both methods to predict treatment outcomes for other antibiotics.

PBPK Modeling and Simulation of Antibiotics Amikacin, Gentamicin, Tobramycin, and Vancomycin Used in Hospital Practice

The importance of closely observing patients receiving antibiotic therapy, performing therapeutic drug monitoring (TDM), and regularly adjusting dosing regimens has been extensively demonstrated. Additionally, antibiotic resistance is a contemporary concerningly dangerous issue. Optimizing the use of antibiotics is crucial to ensure treatment efficacy and prevent toxicity caused by overdosing, as well as to combat the prevalence and wide spread of resistant strains. Some antibiotics have been selected and reserved for the treatment of severe infections, including amikacin, gentamicin, tobramycin, and vancomycin. Critically ill patients often require long treatments, hospitalization, and require particular attention regarding TDM and dosing adjustments. As these antibiotics are eliminated by the kidneys, critical deterioration of renal function and toxic effects must be prevented. In this work, clinical data from a Portuguese cohort of 82 inpatients was analyzed and physiologically based pharmacokinetic (PBPK) modeling and simulation was used to study the influence of different therapeutic regimens and parameters as biological sex, body weight, and renal function on the biodistribution and pharmacokinetic (PK) profile of these four antibiotics. Renal function demonstrated the greatest impact on plasma concentration of these antibiotics, and vancomycin had the most considerable accumulation in plasma over time, particularly in patients with impaired renal function. Thus, through a PBPK study, it is possible to understand which pharmacokinetic parameters will have the greatest variation in a given population receiving antibiotic administrations in hospital context.

Acute gastroenteritis and the usage pattern of antibiotics and traditional herbal medications for its management in a Nigerian community

Acute gastroenteritis (AGE) is the highest cause of mortality worldwide in children under the age of 5 years, with the highest mortalities occurring in low-to-middle income countries. Treatment can involve use of unregulated herbal medication and antibiotics. A cross sectional study was carried out to investigate the use of antibiotics and traditional herbal medications in the management of AGE among Yòrùbá-speaking communities in Kwara State, Nigeria. Our findings suggest habitual use of antibiotics (54.6%) and herbal medication (42.5%) in the management of AGE with high levels of self-prescription of antibiotics (21.7%) and herbal medications (36.2%) within the community. Ethanolic extracts of selected herbal plants reported (i.e. Aristolochia ringens, Azadirachta indica, Chromolaena odorata, Etanda Africana, Ficus capensis, Ficus vogelii, Mangifera indica, Momordica charantia, Ocimum gratisimum, Senna alata, Sorghum bicolor and Vernonia amygdalina) were investigated for antibacterial properties, using bacteria known to be causative agents of AGE. Our findings showed that, with exception of Ficus vogelii, which enhanced bacterial growth, the plant extracts reported all showed some antibacterial activity. We further discuss our findings within a regulatory context, with the aim to guide the use of traditional and herbal medication in low-to medium income countries (LMICs) and reduce the potential risks associated with the development of antimicrobial resistance.

A systematic review from basics to omics on bacteriophage applications in poultry production and processing

The growing human population is currently facing an unprecedented challenge on global food production and sustainability. Despite recognizing poultry as one of the most successful and rapidly growing food industries to address this challenge; poultry health and safety remain major issues that entail immediate attention. Bacterial diseases including colibacillosis, salmonellosis, and necrotic enteritis have become increasingly prevalent during poultry production. Likewise, outbreaks caused by consumption of undercooked poultry products contaminated with zoonotic bacterial pathogens such as Salmonella, Campylobacter and Listeria, are a serious public health concern. With antimicrobial resistance problem and restricted use of antibiotics in food producing animals, bacteriophages are increasingly recognized as an attractive natural antibacterial alternative. Bacteriophages have recently shown promising results to treat diseases in poultry, reduce contamination of carcasses, and enhance the safety of poultry products. Omics technologies have been successfully employed to accurately characterize bacteriophages and their genes/proteins important for interaction with bacterial hosts. In this review, the potential of using lytic bacteriophages to mitigate the risk of major poultry-associated bacterial pathogens are explored. This study also explores challenges associated with the adoption of this technology by industries. Furthermore, the impact of omics approaches on studying bacteriophages, their host interaction and applications is discussed.

Management of Infections Caused by Multidrug-resistant Gram-negative Pathogens: Recent Advances and Future Directions

During the last decades, the isolation of multidrug-resistant Gram-negative (MDR-GN) bacteria has dramatically increased worldwide and has been associated with significant delays in the administration of adequate antibiotic treatment, resulting in increased morbidity and mortality rates. Given specific challenges to effective therapy with old antibiotics, there is the need to establish adequate clinical and therapeutic recommendations for antibiotic treatment of MDR-GN pathogens. Herein, we will review risk factors for harbouring infections due to MDR-GN bacteria, proposing an algorithm for the choice of empirical treatment when a MDR-GN pathogen is suspected. In addition, we will report our recommendations regarding the first- and second-line treatment options for hospitalized patients with serious infections caused by extended-spectrum β-lactamases producing Enterobacterales, carbapenem-resistant Enterobacterales, MDR Pseudomonas aeruginosa and MDR Acinetobacter baumannii. Recommendations have been specially focused, for each pathogen, on bloodstream infections, nosocomial pneumonia, and urinary tract infections.

Isolation and Characterization of the Polyhexamethylene Biguanide Hydrochloride-Resistant Fungus, Purpureocillium lilacinum

We isolated a fungus from a 20% (= 200,000 µg/mL) aqueous solution of polyhexamethylene biguanide hydrochloride (PHMB), a widely used antimicrobial and examined its morphology and drug resistance profile. Based on the sequence of the internal transcribed spacer region of ribosomal DNA, the fungus was identified as Purpureocillium lilacinum. Although the P. lilacinum type and resistant strains showed similar morphology, the latter had extremely low PHMB susceptibility and was able to grow in 20% aqueous solution of PHMB, which eliminated the type strain. The minimum inhibitory concentration (MIC) of PHMB for the resistant strain was significantly higher than that of the type strain and other pathogenic filamentous fungi and yeasts. The susceptibility to antimicrobial agents and antifungal agents other than PHMB was similar to that of the type strain, therefore the drug resistance of the isolate was specific to PHMB. Furthermore, we sequenced the genome of the isolate to predict PHMB resistance-related genes. Despite its high resistance to PHMB, no well-known genes homologous to fungal PHMB-resistant genes were detected in the genome of the resistant strain. In summary, P. lilacinum was found to be significantly more resistant to PHMB than previously reported, via an unidentified mechanism of drug resistance.

Antimicrobial Peptides and Their Applications in Biomedical Sector

In a report by WHO (2014), it was stated that antimicrobial resistance is an arising challenge that needs to be resolved. This resistance is a critical issue in terms of disease or infection treatment and is usually caused due to mutation, gene transfer, long-term usage or inadequate use of antimicrobials, survival of microbes after consumption of antimicrobials, and the presence of antimicrobials in agricultural feeds. One of the solutions to this problem is antimicrobial peptides (AMPs), which are ubiquitously present in the environment. These peptides are of concern due to their special mode of action against a wide spectrum of infections and health-related problems. The biomedical field has the highest need of AMPs as it possesses prominent desirable activity against HIV-1, skin cancer, breast cancer, in Behcet's disease treatment, as well as in reducing the release of inflammatory cells such as TNFα, IL-8, and IL-1β, enhancing the production of anti-inflammatory cytokines such as IL-10 and GM-CSF, and in wound healing properties. This review has highlighted all the major functions and applications of AMPs in the biomedical field and concludes the future potential of AMPs.

Best Practices: CT-Guided Percutaneous Sampling of Vertebral Discitis-Osteomyelitis and Technical Factors Maximizing Biopsy Yield

Vertebral discitis-osteomyelitis is an infection of the intervertebral disk and vertebral bodies that may extend to adjacent paraspinal and epidural soft tissues. Its incidence is increasing, likely because of improved treatments and increased life expectancy for patients with predisposing chronic disease and increased rates of IV drug use and intravascular intervention. Because blood cultures are frequently negative in patients with vertebral discitis-osteomyelitis, biopsy is often indicated to identify a causative microorganism for targeted antimicrobial therapy. The reported yield of CT-guided percutaneous sampling is 31-91%, which is lower than the reported yield of open biopsy of 76-91%. However, the less invasive approach may be favored given its relative safety and low cost. If paravertebral fluid collections are present, CT-guided aspiration should be performed. If aspiration is unsuccessful or no paravertebral fluid collections are present, CT-guided percutaneous biopsy should be performed, considering technical factors (e.g., anatomic approach, needle selection, and needle angulation) that may improve microbiologic yield. Although antimicrobial therapy should be withheld for 1-2 weeks before biopsy if clinically feasible, biopsy may still be performed without stopping antimicrobial therapy if needed. Because of the importance of targeted antimicrobial therapy, repeat biopsy should be considered after 72 hours if initial biopsy does not identify a pathogen.

Epidemiology of Newcastle disease in Africa with emphasis on Côte d'Ivoire: A review

For decades, Newcastle disease (ND) has long been recognized as a frontline viral disease that constrains poultry production throughout Africa. The need to update on the epidemiology of the disease is rife, due to the increasing importance of poultry farming. In addition, poultry farming serves as the top animal food source globally. However, in Africa, the greater population of poultry is reared under traditional and conventional husbandry methods. This hugely impedes the ability of management practices to be correctly embraced in limiting or excluding viral pathogens in the poultry production chain. We conducted this review to consolidate recently published studies in the field and provide an overview of the disease. We reviewed original studies conducted on ND, the current taxonomic classification of the virus, clinical signs of the disease, and laboratory diagnostic methods available for virus detection and typing. This review additionally examined the control methods currently used, including available or circulating vaccines, vaccinations, recent vaccine findings, and the main variants of the virus present in West Africa. More specifically, we present a review of the current status and available information on the disease in Côte d’Ivoire. The lack of up-to-date and relevant information on the current prevalence, socio-economic impact, and ethnoveterinary medicine used against ND is probably the main limitation for appropriate and effective decision-making for better control of this disease in Côte d’Ivoire.

Antimicrobial stewardship program in pediatric medicine

The rising threats from antimicrobial resistance due to inappropriate utilization of antimicrobial agents in health care including the pediatric population has been a topic of concern at the global level for the last several decades. The antimicrobial stewardship program (ASP) is a multidisciplinary institutional initiative focusing primarily on the improvement of antimicrobial prescribing practices and limiting inappropriate use. ASPs play an important role in the implementation of healthcare strategies in pediatrics worldwide to reduce antimicrobial resistance. Many published reports demonstrate how adapted ASPs in pediatrics result in improvement of unnecessary antimicrobial utilization, decreasing drug resistance and treatment failure, minimization of adverse clinical outcomes, decreasing healthcare costs and hospital length of stay, and optimization of diagnostic strategies. However, some barriers in pediatric ASP still exist. This narrative review describes core elements of ASP, the impact of implemented ASPs on pediatric healthcare, and challenges of pediatric ASP as seen by the authors.

Quorum-sensing regulation of virulence factors in bacterial biofilm

Chronic polymicrobial wound infections are often characterized by the presence of bacterial biofilms. They show considerable structural and functional heterogeneity, which influences the choice of antimicrobial therapy and wound healing dynamics. The hallmarks of biofilm-associated bacterial infections include elevated antibiotic resistance and extreme pathogenicity. Biofilm helps bacteria to evade the host defense mechanisms and persist longer in the host. Quorum-sensing (QS)-mediated cell signaling primarily regulates biofilm formation in chronic infections and plays a major role in eliciting virulence. This review focuses on the QS mechanisms of two major bacterial pathogens, Staphylococcus aureus and Pseudomonas aeruginosa and explains how they interact in the wound microenvironment to regulate biofilm development and virulence. The review also provides an insight into the treatment modalities aimed at eradicating polymicrobial biofilms. This information will help us develop better diagnostic modalities and devise effective treatment regimens to successfully manage and overcome severe life-threatening bacterial infections.

An in vitro model for the cultivation of polymicrobial biofilms under continuous-flow conditions

The airways of people with cystic fibrosis (CF) are often chronically colonised with a diverse array of bacterial and fungal species. However, little is known about the relative partitioning of species between the planktonic and biofilm modes of growth in the airways. Existing in vivo and in vitro models of CF airway infection are ill-suited for the long-term recapitulation of mixed microbial communities. Here we describe a simple, in vitro continuous-flow model for the cultivation of polymicrobial biofilms and planktonic cultures on different substrata. Our data provide evidence for inter-species antagonism and synergism in biofilm ecology. We further show that the type of substratum on which the biofilms grow has a profound influence on their species composition. This happens without any major alteration in the composition of the surrounding steady-state planktonic community. Our experimentally-tractable model enables the systematic study of planktonic and biofilm communities under conditions that are nutritionally reminiscent of the CF airway microenvironment, something not possible using any existing in vivo models of CF airway infection.

Impacts of Pharmacy Intervention on Appropriateness of Antibiotics Use in Pneumonia Patients

AIM: This study analyzed the impact of pharmacy intervention on appropriateness of antibiotics use in the treatment of inpatients with pneumonia admitted to Universitas Sumatera Utara (USU) Hospital, Medan, Indonesia. METHODS: This cohort study analyzed appropriateness of antibiotic use in the treatment of in-patients with pneumonia without interventions or baseline group (n = 33) admitted to USU Hospital year 2018 and 3-month period admission with pharmacy intervention (n = 42) year 2019. Characteristics of the patients and antibiotics provided to both groups were descriptively analyzed. The appropriateness of antibiotics use in both groups was analyzed based on their medical conditions, culture and sensitivity tests, and trustable literatures, and then categorized applying Gyssens method regarding dose, intervals, routes, length of provision, effectivity, and costs. The significant difference in inappropriate use of antibiotics between groups with and without interventions was analyzed applying unpaired t-test (p < 0.05 was considered statistically significant). RESULTS: Most of the pneumonia patients in both groups were male. Mean age of the patients (years) in group: without intervention, 60.20 ± 15.48; with intervention, 60.48 ± 14.76. The three most widely provided antibiotics were ceftriaxone, meropenem, and ciprofloxacin. Incidence of inappropriate use of antibiotics per patient in group: without intervention, 0.66; with intervention, 0.33. The inappropriate use of antibiotics reduced significantly in group with intervention, p = 0.049. CONCLUSIONS: Pharmacy intervention is crucial to reduce the inappropriate use of antibiotics in the treatment of pneumonia.