-
Nature Reviews. Microbiology Jul 2023Streptococcus pyogenes (Group A Streptococcus; GAS) is exquisitely adapted to the human host, resulting in asymptomatic infection, pharyngitis, pyoderma, scarlet fever... (Review)
Review
Streptococcus pyogenes (Group A Streptococcus; GAS) is exquisitely adapted to the human host, resulting in asymptomatic infection, pharyngitis, pyoderma, scarlet fever or invasive diseases, with potential for triggering post-infection immune sequelae. GAS deploys a range of virulence determinants to allow colonization, dissemination within the host and transmission, disrupting both innate and adaptive immune responses to infection. Fluctuating global GAS epidemiology is characterized by the emergence of new GAS clones, often associated with the acquisition of new virulence or antimicrobial determinants that are better adapted to the infection niche or averting host immunity. The recent identification of clinical GAS isolates with reduced penicillin sensitivity and increasing macrolide resistance threatens both frontline and penicillin-adjunctive antibiotic treatment. The World Health Organization (WHO) has developed a GAS research and technology road map and has outlined preferred vaccine characteristics, stimulating renewed interest in the development of safe and effective GAS vaccines.
Topics: Humans; Anti-Bacterial Agents; Macrolides; Drug Resistance, Bacterial; Streptococcal Infections; Streptococcus pyogenes; Penicillins
PubMed: 36894668
DOI: 10.1038/s41579-023-00865-7 -
European Respiratory Review : An... Jun 2023Bronchiectasis is a common progressive respiratory disease with recognisable radiological abnormalities and a clinical syndrome of cough, sputum production and recurrent...
Bronchiectasis is a common progressive respiratory disease with recognisable radiological abnormalities and a clinical syndrome of cough, sputum production and recurrent respiratory infections. Inflammatory cell infiltration into the lung, in particular neutrophils, is central to the pathophysiology of bronchiectasis. Herein we explore the roles and relationships between infection, inflammation and mucociliary clearance dysfunction in the establishment and progression of bronchiectasis. Microbial and host-mediated damage are important processes underpinning bronchiectasis and the relative contribution of proteases, cytokines and inflammatory mediators to the propagation of inflammation is presented. We also discuss the emerging concept of inflammatory endotypes, defined by the presence of neutrophilic and eosinophilic inflammation, and explore the role of inflammation as a treatable trait. Current treatment for bronchiectasis focuses on treatment of underlying causes, enhancing mucociliary clearance, controlling infection and preventing and treating complications. Data on airway clearance approaches exercise and mucoactive drugs, pharmacotherapy with macrolides to decrease exacerbations and the usefulness of inhaled antibiotics and bronchodilators are discussed, finishing with a look to the future where new therapies targeting host-mediated immune dysfunction hold promise.
Topics: Humans; Adult; Bronchiectasis; Inflammation; Cough; Anti-Bacterial Agents; Macrolides
PubMed: 37286220
DOI: 10.1183/16000617.0015-2023 -
International Journal of Molecular... Jul 2023Despite innovative advances in anti-infective therapies and vaccine development technologies, community-acquired pneumonia (CAP) remains the most persistent cause of... (Review)
Review
The Global Burden of Community-Acquired Pneumonia in Adults, Encompassing Invasive Pneumococcal Disease and the Prevalence of Its Associated Cardiovascular Events, with a Focus on Pneumolysin and Macrolide Antibiotics in Pathogenesis and Therapy.
Despite innovative advances in anti-infective therapies and vaccine development technologies, community-acquired pneumonia (CAP) remains the most persistent cause of infection-related mortality globally. Confronting the ongoing threat posed by (the pneumococcus), the most common bacterial cause of CAP, particularly to the non-immune elderly, remains challenging due to the propensity of the elderly to develop invasive pneumococcal disease (IPD), together with the predilection of the pathogen for the heart. The resultant development of often fatal cardiovascular events (CVEs), particularly during the first seven days of acute infection, is now recognized as a relatively common complication of IPD. The current review represents an update on the prevalence and types of CVEs associated with acute bacterial CAP, particularly IPD. In addition, it is focused on recent insights into the involvement of the pneumococcal pore-forming toxin, pneumolysin (Ply), in subverting host immune defenses, particularly the protective functions of the alveolar macrophage during early-stage disease. This, in turn, enables extra-pulmonary dissemination of the pathogen, leading to cardiac invasion, cardiotoxicity and myocardial dysfunction. The review concludes with an overview of the current status of macrolide antibiotics in the treatment of bacterial CAP in general, as well as severe pneumococcal CAP, including a consideration of the mechanisms by which these agents inhibit the production of Ply by macrolide-resistant strains of the pathogen.
Topics: Adult; Humans; Aged; Pneumonia, Pneumococcal; Prevalence; Pneumococcal Infections; Streptococcus pneumoniae; Anti-Bacterial Agents; Macrolides; Community-Acquired Infections; Cardiovascular Diseases
PubMed: 37446214
DOI: 10.3390/ijms241311038 -
Indian Journal of Medical Microbiology 2023Mycoplasmas are the smallest prokaryotic microorganisms found in nature. Mycoplasma pneumoniae (M. pneumoniae) is the most commonly studied among human mycoplasmas. (Review)
Review
BACKGROUND
Mycoplasmas are the smallest prokaryotic microorganisms found in nature. Mycoplasma pneumoniae (M. pneumoniae) is the most commonly studied among human mycoplasmas.
OBJECTIVES
In this review, we briefly focus on the recent developments that have enhanced our understanding of M. pneumoniae, one of the smallest pathogenic bacteria of great clinical importance in children.
CONTENT
M. pneumoniae infections may involve either upper or lower respiratory tract or both of them. Extrapulmonary manifestations have been reported in almost every organ, including the skin and the hematologic, cardiovascular, musculoskeletal, and nervous system due to direct local effects, after dissemination of bacteria or indirect effects. The correct identification of M. pneumoniae infections is vital for prescription of the appropriate therapy.There are scarce specific findings of clinical laboratory results for the diagnosis of M. pneumoniae infection. Detection of M. pneumoniae infections can be achieved using culture, serology, or molecular-based methods. Culture is time-consuming, laborious, and expensive. The major types of serological tests for M. pneumoniae include the microtiter plate enzyme immunoassay (EIA), the membrane EIA, indirect immunofluorescence, and particle agglutination. Nucleic acid amplification tests (NAATs) include traditional PCR, nested PCR, real-time quantitative PCR, nucleic acid sequence-based amplification (NASBA), loop-mediated isothermal amplification (LAMP) technology, and RNA simultaneous amplification and testing (SAT). Macrolides have been the drug of choice for treating M. pneumoniae infection in past years. Clinically significant acquired macrolide-resistant M. pneumoniae (MRMP)has emerged worldwide which may be associated with more extrapulmonary complications, and severe clinical and radiological features. Since molecular-based assays can detect M. pnueumoniae in clinical specimens, there is a need for real point of care testing for fast detection of M. pneumoniae or its DNA and mutations in macrolide resistance gene. It is necessary to develop safe vaccines that provide protective immunity against M.pneumoniae infection.
Topics: Child; Humans; Mycoplasma pneumoniae; Anti-Bacterial Agents; Pneumonia, Mycoplasma; Clinical Relevance; Macrolides; Drug Resistance, Bacterial; Real-Time Polymerase Chain Reaction
PubMed: 37741157
DOI: 10.1016/j.ijmmb.2023.100480 -
Open-Label Trial of Amikacin Liposome Inhalation Suspension in Mycobacterium abscessus Lung Disease.Chest Oct 2023Mycobacterium abscessus is the second most common nontuberculous mycobacterium respiratory pathogen and shows in vitro resistance to nearly all oral antimicrobials. M...
BACKGROUND
Mycobacterium abscessus is the second most common nontuberculous mycobacterium respiratory pathogen and shows in vitro resistance to nearly all oral antimicrobials. M abscessus treatment success is low in the presence of macrolide resistance.
RESEARCH QUESTION
Does treatment with amikacin liposome inhalation suspension (ALIS) improve culture conversion in patients with M abscessus pulmonary disease who are treatment naive or who have treatment-refractory disease?
STUDY DESIGN AND METHODS
In an open-label protocol, patients were given ALIS (590 mg) added to background multidrug therapy for 12 months. The primary outcome was sputum culture conversion defined as three consecutive monthly sputum cultures showing negative results. The secondary end point included development of amikacin resistance.
RESULTS
Of 33 patients (36 isolates) who started ALIS with a mean age of 64 years (range, 14-81 years), 24 patients (73%) were female, 10 patients (30%) had cystic fibrosis, and nine patients (27%) had cavitary disease. Three patients (9%) could not be evaluated for the microbiologic end point because of early withdrawal. All pretreatment isolates were amikacin susceptible and only six isolates (17%) were macrolide susceptible. Eleven patients (33%) were given parenteral antibiotics. Twelve patients (40%) received clofazimine with or without azithromycin as companion therapy. Fifteen patients (50%) with evaluable longitudinal microbiologic data demonstrated culture conversion, and 10 patients (67%) sustained conversion through month 12. Six of the 33 patients (18%) demonstrated mutational amikacin resistance. All were patients using clofazimine or clofazimine plus azithromycin as companion medication(s). Few serious adverse events occurred for ALIS users; however, reduction of dosing to three times weekly was common (52%).
INTERPRETATION
In a cohort of patients primarily with macrolide-resistant M abscessus, one-half of the patients using ALIS showed sputum culture conversion to negative findings. The emergence of mutational amikacin resistance was not uncommon and occurred with the use of clofazimine monotherapy.
TRIAL REGISTRY
ClinicalTrials.gov; No.: NCT03038178; URL: www.
CLINICALTRIALS
gov.
Topics: Humans; Female; Middle Aged; Male; Amikacin; Anti-Bacterial Agents; Mycobacterium abscessus; Liposomes; Clofazimine; Azithromycin; Macrolides; Drug Resistance, Bacterial; Leprostatic Agents; Cystic Fibrosis; Mycobacterium Infections, Nontuberculous; Microbial Sensitivity Tests
PubMed: 37419144
DOI: 10.1016/j.chest.2023.05.036 -
Pharmacotherapy Sep 2023To investigate risk of aortic aneurysm or dissection in patients using oral fluoroquinolones compared to those using macrolides in real-world clinical practice among a...
STUDY OBJECTIVE
To investigate risk of aortic aneurysm or dissection in patients using oral fluoroquinolones compared to those using macrolides in real-world clinical practice among a large US general population.
DESIGN
Retrospective cohort study design.
DATA SOURCE
MarketScan commercial and Medicare supplemental databases.
PATIENTS
Adults patients with at least one prescription fill for fluoroquinolone or macrolide antibiotics.
INTERVENTION
Fluoroquinolone or macrolide antibiotics.
MEASUREMENTS AND MAIN RESULTS
The primary outcome was estimated incidence of aortic aneurysm or dissection associated with the use of fluoroquinolones compared with macrolides during a 60-day follow-up period in a 1:1 propensity score-matched cohort. We identified 3,174,620 patients (1,587,310 in each group) after 1:1 propensity score matching. Crude incidence of aortic aneurysm or dissection was 1.9 cases per 1000 person-years among fluoroquinolone users and 1.2 cases per 1000 person-years among macrolide users. In multivariable Cox regression, compared with macrolides, the use of fluoroquinolones was associated with an increased risk of aortic aneurysm or dissection (aHR: 1.34; 95% CI: 1.17-1.54). The association was primarily driven by a high incidence of aortic aneurysm cases (95.8%). Results of sensitivity (e.g., fluoroquinolone exposure ranging from 7 to 14 days (aHR: 1.47; 95% CI: 1.26-1.71)) and subgroup analyses (e.g., ciprofloxacin (aHR: 1.26; 95% CI: 1.07-1.49) and levofloxacin (aHR: 1.44; 95% CI: 1.19-1.52)) remained consistent with main findings.
CONCLUSIONS
Fluoroquinolone use was associated with a 34% increased risk of aortic aneurysm or dissection compared with macrolide use among a general US population.
Topics: Adult; Humans; Aged; United States; Fluoroquinolones; Cohort Studies; Propensity Score; Retrospective Studies; Aortic Dissection; Medicare; Aortic Aneurysm; Anti-Bacterial Agents; Macrolides
PubMed: 37381584
DOI: 10.1002/phar.2841 -
Transplant International : Official... 2023
Topics: Humans; Immunosuppressive Agents; Tacrolimus
PubMed: 38149082
DOI: 10.3389/ti.2023.12423 -
International Journal of Antimicrobial... Sep 2023Guidelines recommend respiratory fluoroquinolone monotherapy or β-lactam plus macrolide combination therapy as first-line options for hospitalized adults with... (Meta-Analysis)
Meta-Analysis Review
Respiratory fluoroquinolone monotherapy vs. β-lactam plus macrolide combination therapy for hospitalized adults with community-acquired pneumonia: A systematic review and meta-analysis of randomized controlled trials.
INTRODUCTION
Guidelines recommend respiratory fluoroquinolone monotherapy or β-lactam plus macrolide combination therapy as first-line options for hospitalized adults with mild-to-moderate community-acquired pneumonia (CAP). Efficacy of these regimens has not been adequately evaluated.
METHODS
A systematic review of randomized controlled trials (RCTs) comparing respiratory fluoroquinolone monotherapy and β-lactam plus macrolide combination therapy in hospitalised adults with CAP was performed. A meta-analysis was performed using a random effects model. The primary outcome was clinical cure rate. Quality of evidence (QoE) was evaluated using GRADE methodology.
RESULTS
A total of 4140 participants in 18 RCTs were included. Levofloxacin (11 trials) or moxifloxacin (6 trials) were the predominant respiratory fluoroquinolones evaluated, and the β-lactam plus macrolide group used ceftriaxone plus a macrolide (10 trials), cefuroxime plus azithromycin (5 trials), and amoxicillin/clavulanate plus a macrolide (2 trials). Patients receiving respiratory fluoroquinolone monotherapy had a significantly higher clinical cure rate (86.5% vs. 81.5%; odds ratio [OR] 1.47; 95% confidence interval [95% CI: 1.17-1.83]; P = 0.0008; I = 0%; 17 RCTs; moderate QoE) and microbiological eradication rate (86.0% vs. 81.0%; OR 1.51 [95% CI: 1.00-2.26]; P = 0.05; I = 0%; 15 RCTs; moderate QoE) than patients receiving β-lactam plus macrolide combination therapy. All-cause mortality (7.2% vs. 7.7%; OR 0.88 [95% CI: 0.67-1.17]; I = 0%; low QoE) and adverse events (24.8% vs. 28.1%; OR 0.87 [95% CI: 0.69-1.09]; I = 0%; low QoE] were similar in the two groups.
CONCLUSION
Respiratory fluoroquinolone monotherapy demonstrated an advantage in clinical cure and microbiological eradication; however, it did not impact mortality.
Topics: Adult; Humans; beta-Lactams; Fluoroquinolones; Macrolides; Pneumonia, Bacterial; Drug Therapy, Combination; Randomized Controlled Trials as Topic; Anti-Bacterial Agents; Community-Acquired Infections
PubMed: 37385561
DOI: 10.1016/j.ijantimicag.2023.106905 -
American Journal of Obstetrics &... Jul 2023Various prophylactic antibiotic regimens are used in the management of preterm premature rupture of membranes. We investigated the efficacy and safety of these regimens... (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
Various prophylactic antibiotic regimens are used in the management of preterm premature rupture of membranes. We investigated the efficacy and safety of these regimens in terms of maternal and neonatal outcomes.
DATA SOURCES
We searched PubMed, Embase, and the Cochrane Central Register of Controlled Trials from inception to July 20, 2021.
STUDY ELIGIBILITY CRITERIA
We included randomized controlled trials involving pregnant women with preterm premature rupture of membranes before 37 weeks of gestation and a comparison of ≥2 of the following 10 antibiotic regimens: control/placebo, erythromycin, clindamycin, clindamycin plus gentamicin, penicillins, cephalosporins, co-amoxiclav, co-amoxiclav plus erythromycin, aminopenicillins plus macrolides, and cephalosporins plus macrolides.
METHODS
Two investigators independently extracted published data and assessed the risk of bias with a standard procedure following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Network meta-analysis was conducted using the random-effects model.
RESULTS
A total of 23 studies that recruited a total of 7671 pregnant women were included. Only penicillins (odds ratio, 0.46; 95% confidence interval, 0.27-0.77) had significantly superior effectiveness for maternal chorioamnionitis. Clindamycin plus gentamicin reduced the risk of clinical chorioamnionitis, with borderline significance (odds ratio, 0.16; 95% confidence interval, 0.03-1.00). By contrast, clindamycin alone increased the risk of maternal infection. For cesarean delivery, no significant differences were noted among these regimens.
CONCLUSION
Penicillins remain the recommended antibiotic regimen for reducing maternal clinical chorioamnionitis. The alternative regimen includes clindamycin plus gentamicin. Clindamycin should not be used alone.
Topics: Infant, Newborn; Pregnancy; Female; Humans; Clindamycin; Chorioamnionitis; Amoxicillin-Potassium Clavulanate Combination; Network Meta-Analysis; Anti-Bacterial Agents; Premature Birth; Erythromycin; Macrolides; Gentamicins; Cephalosporins
PubMed: 37094635
DOI: 10.1016/j.ajogmf.2023.100978 -
Molecular Cell Jul 2023The spliceosome is a staggeringly complex machine, comprising, in humans, 5 snRNAs and >150 proteins. We scaled haploid CRISPR-Cas9 base editing to target the entire...
The spliceosome is a staggeringly complex machine, comprising, in humans, 5 snRNAs and >150 proteins. We scaled haploid CRISPR-Cas9 base editing to target the entire human spliceosome and investigated the mutants using the U2 snRNP/SF3b inhibitor, pladienolide B. Hypersensitive substitutions define functional sites in the U1/U2-containing A complex but also in components that act as late as the second chemical step after SF3b is dissociated. Viable resistance substitutions map not only to the pladienolide B-binding site but also to the G-patch domain of SUGP1, which lacks orthologs in yeast. We used these mutants and biochemical approaches to identify the spliceosomal disassemblase DHX15/hPrp43 as the ATPase ligand for SUGP1. These and other data support a model in which SUGP1 promotes splicing fidelity by triggering early spliceosome disassembly in response to kinetic blocks. Our approach provides a template for the analysis of essential cellular machines in humans.
Topics: Humans; Spliceosomes; Epoxy Compounds; Macrolides; RNA Splicing; Saccharomyces cerevisiae; Mutagenesis
PubMed: 37402368
DOI: 10.1016/j.molcel.2023.06.003