Divyadarshini Angamuthu, Sandhya Vivekanandan, Luke Elizabeth Hanna
{"title":"Experimental models for HIV latency and molecular tools for reservoir quantification-an update.","authors":"Divyadarshini Angamuthu, Sandhya Vivekanandan, Luke Elizabeth Hanna","doi":"10.1128/cmr.00013-23","DOIUrl":"10.1128/cmr.00013-23","url":null,"abstract":"<p><p>A major impediment for HIV cure is the ability of the virus to integrate its genome in the form of replication-competent proviral DNA into the cellular genome of the host and remain transcriptionally silent and hidden from the host's immune defense mechanisms in latent reservoir cells. These latent reservoirs are highly heterogeneous, long-lived cells that are capable of reactivating to restore the viremic stage in virally suppressed individuals upon treatment interruption, thus necessitating life-long antiretroviral treatment. Latency reversal has become one of the most explored therapeutic approaches for eliminating HIV reservoirs and effecting HIV cure. Various aspects governing the establishment, maintenance, and reversal of HIV latency continue to be an enigma and warrant further research. Quantifying the size of the latent reservoir pool is also a challenge as these cells are very few in number and cannot be easily differentiated from uninfected cells. This article provides a comprehensive review of the <i>in vitro</i> and <i>in vivo</i> models currently available for studying HIV latency as well as the recently developed molecular tools for detection and quantification of latent viral reservoirs.</p>","PeriodicalId":10378,"journal":{"name":"Clinical Microbiology Reviews","volume":" ","pages":"e0001323"},"PeriodicalIF":9.6,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10732067/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"107590423","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Invasive fusariosis.","authors":"Marcio Nucci, Elias Anaissie","doi":"10.1128/cmr.00159-22","DOIUrl":"10.1128/cmr.00159-22","url":null,"abstract":"<p><p>Invasive fusariosis is a serious invasive fungal disease, affecting immunocompetent and, more frequently, immunocompromised patients. Localized disease is the typical clinical form in immunocompetent patients. Immunocompromised hosts at elevated risk of developing invasive fusariosis are patients with acute leukemia receiving chemotherapeutic regimens for remission induction, and those undergoing allogeneic hematopoietic cell transplant. In this setting, the infection is usually disseminated with positive blood cultures, multiple painful metastatic skin lesions, and lung involvement. Currently available antifungal agents have poor <i>in vitro</i> activity against <i>Fusarium</i> species, but a clear-cut correlation between <i>in vitro</i> activity and clinical effectiveness does not exist. The outcome of invasive fusariosis is largely dependent on the resolution of immunosuppression, especially neutrophil recovery in neutropenic patients.</p>","PeriodicalId":10378,"journal":{"name":"Clinical Microbiology Reviews","volume":" ","pages":"e0015922"},"PeriodicalIF":19.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10732078/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71478800","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The potential for development of clinically relevant microbial resistance to rifaximin-α: a narrative review.","authors":"Herbert L DuPont","doi":"10.1128/cmr.00039-23","DOIUrl":"10.1128/cmr.00039-23","url":null,"abstract":"<p><p>Rifaximin-α is a gut-targeted antibiotic indicated for numerous gastrointestinal and liver diseases. Its multifaceted mechanism of action goes beyond direct antimicrobial effects, including alterations in bacterial virulence, cytoprotective effects on host epithelial cells, improvement of impaired intestinal permeability, and reduction of proinflammatory cytokine expression via activation of the pregnane X receptor. Rifaximin-α is virtually non-absorbed, with low systemic drug levels contributing to its excellent safety profile. While there are high concentrations of drug in the colon, low water solubility leads to low colonic drug bioavailability, protecting the gut microbiome. Rifaximin-α appears to be more active in the bile-rich small bowel. Its important biologic effects are largely at sub-inhibitory concentration. Although <i>in vitro</i> testing of clinical isolates from rifaximin recipients has revealed rifaximin-resistant strains in some studies, the risk of emergent rifaximin-α resistance appears to be lower than for many other antibiotics. Rifaximin-α has been used for many years for traveler's diarrhea with no apparent increase in resistance levels in causative pathogens. Further, rifaximin-α retains its efficacy after long-term and recurrent usage in chronic gastrointestinal disorders. There are numerous reasons why the risk of microbial resistance to rifaximin-α may be lower than that for other agents, including low intestinal bioavailability in the aqueous colon, the mechanisms of action of rifaximin-α not requiring inhibitory concentrations of drug, and the low risk of cross transmission of rifaximin-α resistance between bacterial species. Reported emergence of vancomycin-resistant <i>Enterococcus</i> in liver-disease patients maintained on rifaximin needs to be actively studied. Further studies are required to assess the possible correlation between <i>in vitro</i> resistance and rifaximin-α efficacy.</p>","PeriodicalId":10378,"journal":{"name":"Clinical Microbiology Reviews","volume":" ","pages":"e0003923"},"PeriodicalIF":9.6,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10732030/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136396637","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jhih-Hang Jiang, David R Cameron, Cara Nethercott, Marta Aires-de-Sousa, Anton Y Peleg
{"title":"Virulence attributes of successful methicillin-resistant <i>Staphylococcus aureus</i> lineages.","authors":"Jhih-Hang Jiang, David R Cameron, Cara Nethercott, Marta Aires-de-Sousa, Anton Y Peleg","doi":"10.1128/cmr.00148-22","DOIUrl":"10.1128/cmr.00148-22","url":null,"abstract":"<p><p>Methicillin-resistant <i>Staphylococcus aureus</i> (MRSA) is a leading cause of severe and often fatal infections. MRSA epidemics have occurred in waves, whereby a previously successful lineage has been replaced by a more fit and better adapted lineage. Selection pressures in both hospital and community settings are not uniform across the globe, which has resulted in geographically distinct epidemiology. This review focuses on the mechanisms that trigger the establishment and maintenance of current, dominant MRSA lineages across the globe. While the important role of antibiotic resistance will be mentioned throughout, factors which influence the capacity of <i>S. aureus</i> to colonize and cause disease within a host will be the primary focus of this review. We show that while MRSA possesses a diverse arsenal of toxins including alpha-toxin, the success of a lineage involves more than just producing toxins that damage the host. Success is often attributed to the acquisition or loss of genetic elements involved in colonization and niche adaptation such as the arginine catabolic mobile element, as well as the activity of regulatory systems, and shift metabolism accordingly (e.g., the accessory genome regulator, <i>agr</i>). Understanding exactly how specific MRSA clones cause prolonged epidemics may reveal targets for therapies, whereby both core (e.g., the alpha toxin) and acquired virulence factors (e.g., the Panton-Valentine leukocidin) may be nullified using anti-virulence strategies.</p>","PeriodicalId":10378,"journal":{"name":"Clinical Microbiology Reviews","volume":" ","pages":"e0014822"},"PeriodicalIF":19.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10732075/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138046323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Biofilm antimicrobial susceptibility testing: where are we and where could we be going?","authors":"Tom Coenye","doi":"10.1128/cmr.00024-23","DOIUrl":"10.1128/cmr.00024-23","url":null,"abstract":"<p><p>Our knowledge about the fundamental aspects of biofilm biology, including the mechanisms behind the reduced antimicrobial susceptibility of biofilms, has increased drastically over the last decades. However, this knowledge has so far not been translated into major changes in clinical practice. While the biofilm concept is increasingly on the radar of clinical microbiologists, physicians, and healthcare professionals in general, the standardized tools to study biofilms in the clinical microbiology laboratory are still lacking; one area in which this is particularly obvious is that of antimicrobial susceptibility testing (AST). It is generally accepted that the biofilm lifestyle has a tremendous impact on antibiotic susceptibility, yet AST is typically still carried out with planktonic cells. On top of that, the microenvironment at the site of infection is an important driver for microbial physiology and hence susceptibility; but this is poorly reflected in current AST methods. The goal of this review is to provide an overview of the state of the art concerning biofilm AST and highlight the knowledge gaps in this area. Subsequently, potential ways to improve biofilm-based AST will be discussed. Finally, bottlenecks currently preventing the use of biofilm AST in clinical practice, as well as the steps needed to get past these bottlenecks, will be discussed.</p>","PeriodicalId":10378,"journal":{"name":"Clinical Microbiology Reviews","volume":" ","pages":"e0002423"},"PeriodicalIF":19.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10732061/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41122197","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Changes in fungal taxonomy: mycological rationale and clinical implications.","authors":"Andrew M Borman, Elizabeth M Johnson","doi":"10.1128/cmr.00099-22","DOIUrl":"10.1128/cmr.00099-22","url":null,"abstract":"<p><p>Numerous fungal species of medical importance have been recently subjected to and will likely continue to undergo nomenclatural changes as a result of the application of molecular approaches to fungal classification together with abandonment of dual nomenclature. Here, we summarize those changes affecting key groups of fungi of medical importance, explaining the mycological (taxonomic) rationale that underpinned the changes and the clinical relevance/importance (where such exists) of the key nomenclatural revisions. Potential mechanisms to mitigate unnecessary taxonomic instability are suggested, together with approaches to raise awareness of important changes to minimize potential clinical confusion.</p>","PeriodicalId":10378,"journal":{"name":"Clinical Microbiology Reviews","volume":" ","pages":"e0009922"},"PeriodicalIF":19.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10732072/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71478798","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Li Ding, Siquan Shen, Jing Chen, Zhen Tian, Qingyu Shi, Renru Han, Yan Guo, Fupin Hu
{"title":"<i>Klebsiella pneumoniae</i> carbapenemase variants: the new threat to global public health.","authors":"Li Ding, Siquan Shen, Jing Chen, Zhen Tian, Qingyu Shi, Renru Han, Yan Guo, Fupin Hu","doi":"10.1128/cmr.00008-23","DOIUrl":"10.1128/cmr.00008-23","url":null,"abstract":"<p><p><i>Klebsiella pneumoniae</i> carbapenemase (KPC) variants, which refer to the substitution, insertion, or deletion of amino acid sequence compared to wild <i>bla</i><sub>KPC</sub> type, have reduced utility of ceftazidime-avibactam (CZA), a pioneer antimicrobial agent in treating carbapenem-resistant <i>Enterobacterales</i> infections. So far, more than 150 <i>bla</i><sub>KPC</sub> variants have been reported worldwide, and most of the new variants were discovered in the past 3 years, which calls for public alarm. The KPC variant protein enhances the affinity to ceftazidime and weakens the affinity to avibactam by changing the KPC structure, thereby mediating bacterial resistance to CZA. At present, there are still no guidelines or expert consensus to make recommendations for the diagnosis and treatment of infections caused by KPC variants. In addition, meropenem-vaborbactam, imipenem-relebactam, and other new β-lactam-β-lactamase inhibitor combinations have little discussion on KPC variants. This review aims to discuss the clinical characteristics, risk factors, epidemiological characteristics, antimicrobial susceptibility profiles, methods for detecting <i>bla</i><sub>KPC</sub> variants, treatment options, and future perspectives of <i>bla</i><sub>KPC</sub> variants worldwide to alert this new great public health threat.</p>","PeriodicalId":10378,"journal":{"name":"Clinical Microbiology Reviews","volume":" ","pages":"e0000823"},"PeriodicalIF":19.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10732083/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71478797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Muneyoshi Kimura, Sagar Kothari, Wajiha Gohir, Jose F Camargo, Shahid Husain
{"title":"MicroRNAs in infectious diseases: potential diagnostic biomarkers and therapeutic targets.","authors":"Muneyoshi Kimura, Sagar Kothari, Wajiha Gohir, Jose F Camargo, Shahid Husain","doi":"10.1128/cmr.00015-23","DOIUrl":"10.1128/cmr.00015-23","url":null,"abstract":"<p><p>MicroRNAs (miRNAs) are conserved, short, non-coding RNAs that play a crucial role in the post-transcriptional regulation of gene expression. They have been implicated in the pathogenesis of cancer and neurological, cardiovascular, and autoimmune diseases. Several recent studies have suggested that miRNAs are key players in regulating the differentiation, maturation, and activation of immune cells, thereby influencing the host immune response to infection. The resultant upregulation or downregulation of miRNAs from infection influences the protein expression of genes responsible for the immune response and can determine the risk of disease progression. Recently, miRNAs have been explored as diagnostic biomarkers and therapeutic targets in various infectious diseases. This review summarizes our current understanding of the role of miRNAs during viral, fungal, bacterial, and parasitic infections from a clinical perspective, including critical functional mechanisms and implications for their potential use as biomarkers and therapeutic targets.</p>","PeriodicalId":10378,"journal":{"name":"Clinical Microbiology Reviews","volume":" ","pages":"e0001523"},"PeriodicalIF":19.0,"publicationDate":"2023-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10732047/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71421299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}