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Clinical Microbiology and Infection :... Mar 2019Rhodococcus equi is a recognized cause of disease in humans, especially in individuals who are immunocompromised. Because diphtheroids are regarded as part of normal... (Review)
Review
BACKGROUND
Rhodococcus equi is a recognized cause of disease in humans, especially in individuals who are immunocompromised. Because diphtheroids are regarded as part of normal respiratory flora, the importance of R. equi as a pulmonary pathogen may not be fully appreciated and its prevalence may be underestimated. Most treatment recommendations for R. equi infection were established before antiretroviral drugs became available for human immunodeficiency virus/AIDS therapy, and therapeutic strategies may need to be updated.
OBJECTIVES
To review the role of R. equi as a cause of pulmonary infection; to highlight its importance for clinicians and microbiologists; and to challenge current approaches to treatment, whether in immunodeficient or immunocompetent individuals.
SOURCES
A PubMed search using combinations of the following terms: 'Rhodococcus (automatically including Corynebacterium) equi' AND 'pneumonia' OR 'pulmonary' infection, then cross-checking references in the resulting cases, case series and reviews.
CONTENT
We provide a review that details the challenges in the diagnosis, microbiology and pathogenesis of pulmonary infection caused by R. equi and the options for treatment.
IMPLICATIONS
Ten to 14 days of treatment may be effective for pneumonia due to R. equi. Our review suggests that longer courses of therapy are needed for cavitary lesions and lung masses. However, recommendations for excessively prolonged treatment of all pulmonary infections arose during a time when many cases occurred in individuals with AIDS and before effective antiretroviral therapy was available. We suggest that the rationale for prolonged therapy with multiple antibiotics needs to be re-evaluated.
Topics: AIDS-Related Opportunistic Infections; Actinomycetales Infections; Anti-Bacterial Agents; Disease Management; Humans; Immunocompromised Host; Lung; Pneumonia, Bacterial; Rhodococcus equi
PubMed: 29777923
DOI: 10.1016/j.cmi.2018.04.033 -
Microbiology Spectrum Oct 2017Pneumonia caused by remains an important cause of disease and death in foals. The combination of a macrolide (erythromycin, azithromycin, or clarithromycin) with... (Review)
Review
Pneumonia caused by remains an important cause of disease and death in foals. The combination of a macrolide (erythromycin, azithromycin, or clarithromycin) with rifampin has been the recommended treatment for foals with clinical signs of infection caused by since the early 1980s with, until recently, only rare reports of resistance. Resistance to macrolides and rifampin in isolates of cultured from horses is increasing, with isolates resistant to all macrolides and rifampin now being cultured from up to 40% of infected foals at some farms. This text reviews the available data regarding antimicrobial resistance in , with emphasis on the molecular mechanisms of the recent emergence of resistance to macrolides and rifampin in equine isolates of .
Topics: Animal Diseases; Animals; Anti-Bacterial Agents; Azithromycin; Clarithromycin; Drug Combinations; Drug Resistance, Bacterial; Erythromycin; Fluoroquinolones; Horses; Lincosamides; Macrolides; Microbial Sensitivity Tests; Rhodococcus equi; Rifampin; Streptogramin B
PubMed: 29052538
DOI: 10.1128/microbiolspec.ARBA-0004-2016 -
Veterinary Research 2004Rhodococcus equi is an important cause of subacute or chronic abscessating bronchopneumonia of foals up to 3-5 months of age. It shares the lipid-rich cell wall envelope... (Review)
Review
Rhodococcus equi is an important cause of subacute or chronic abscessating bronchopneumonia of foals up to 3-5 months of age. It shares the lipid-rich cell wall envelope characteristic of the mycolata, including Mycobacterium tuberculosis, as well as the ability of pathogenic members of this group to survive within macrophages. The possession of a large virulence plasmid in isolates recovered from pneumonic foals is crucial for virulence. The plasmid contains an 27 kb pathogenicity island (PI) that encodes seven related virulence-associated proteins (Vaps), including the immunodominant surface-expressed protein, VapA. Only PI genes are differentially expressed when the organism is grown in macrophages in vitro. Ten of the PI genes, including six Vap genes, have signal sequences, suggesting that they are exported from the cell to interact with the macrophage. Different PI genes are regulated by temperature, pH, iron, oxidative stress and probably also by magnesium, all environmental changes encountered after environmental R. equi are inhaled in dust and are ingested into macrophages in the lung. The basis of pathogenicity of R. equi is its ability to multiply in and eventually to destroy alveolar macrophages. Infectivity is largely or exclusively limited to cells of the monocyte-macrophage lineage. Current evidence suggests that infection of foals with virulent R. equi results in some foals in subversion of cell-mediated immunity and development of an ineffective and sometimes lethal Th2-based immune response. Significant progress has been made recently in the development of R. equi-E. coli shuttle vectors, transformation and random and site specific mutagenesis procedures, all of which will be important in molecular dissection of the mechanisms by which R. equi subverts normal macrophage killing mechanisms and cell-mediated immunity.
Topics: Actinomycetales Infections; Animals; Animals, Newborn; Bronchopneumonia; Horse Diseases; Horses; Rhodococcus equi
PubMed: 15236672
DOI: 10.1051/vetres:2004024 -
Pathogens (Basel, Switzerland) Sep 2021infection is commonly known in equine medicine to cause frequently fatal rhodococcosis. Infections in other species and people are also reported. Clinical manifestation...
BACKGROUND
infection is commonly known in equine medicine to cause frequently fatal rhodococcosis. Infections in other species and people are also reported. Clinical manifestation in goats is relatively similar to horses and humans, but data regarding bacterium prevalence are scarce. Thus, the study aimed to estimate the occurrence of in goats.
METHODS
During post mortem examination, submandibular, mediastinal, and mesenteric lymph nodes were collected. Standard methods were used for bacteria isolation and identification.
RESULTS
A total of 134 goats were examined, and 272 lymph node samples were collected. was isolated from four animals. All four isolates carried the gene, and one also had and pVAPN plasmid genes.
CONCLUSIONS
To the authors' best knowledge, this is the first report of occurrence and genetic diversity in goats. The results may help create a model for treating rhodococcosis in other animal species and assessing the role of meat contamination as a potential source of human infection. This research should be considered a pilot study for further application of the goat as a model of infection in horses and humans.
PubMed: 34578172
DOI: 10.3390/pathogens10091141 -
Microbiology and Molecular Biology... May 2021The development and spread of antimicrobial resistance are major concerns for human and animal health. The effects of the overuse of antimicrobials in domestic animals... (Review)
Review
The development and spread of antimicrobial resistance are major concerns for human and animal health. The effects of the overuse of antimicrobials in domestic animals on the dissemination of resistant microbes to humans and the environment are of concern worldwide. is an ideal model to illustrate the spread of antimicrobial resistance at the animal-human-environment interface because it is a natural soil saprophyte that is an intracellular zoonotic pathogen that produces severe bronchopneumonia in many animal species and humans. Globally, is most often recognized as causing severe pneumonia in foals that results in animal suffering and increased production costs for the many horse-breeding farms where the disease occurs. Because highly effective preventive measures for are lacking, thoracic ultrasonographic screening and antimicrobial chemotherapy of subclinically affected foals have been used for controlling this disease during the last 20 years. The resultant increase in antimicrobial use attributable to this "screen-and-treat" approach at farms where the disease is endemic has likely driven the emergence of multidrug-resistant (MDR) in foals and their environment. This review summarizes the factors that contributed to the development and spread of MDR , the molecular epidemiology of the emergence of MDR , the repercussions of MDR for veterinary and human medicine, and measures that might mitigate antimicrobial resistance at horse-breeding farms, such as alternative treatments to traditional antibiotics. Knowledge of the emergence and spread of MDR is of broad importance for understanding how antimicrobial use in domestic animals can impact the health of animals, their environment, and human beings.
Topics: Actinomycetales Infections; Animals; Anti-Bacterial Agents; Drug Resistance, Multiple; Humans; Rhodococcus equi; Soil
PubMed: 33853933
DOI: 10.1128/MMBR.00011-21 -
Journal of Veterinary Internal Medicine 2015Rhodococcus equi pneumonia is a major cause of morbidity and mortality in neonatal foals. Much effort has been made to identify preventative measures and new treatments... (Review)
Review
Rhodococcus equi pneumonia is a major cause of morbidity and mortality in neonatal foals. Much effort has been made to identify preventative measures and new treatments for R. equi with limited success. With a growing focus in the medical community on understanding the genetic basis of disease susceptibility, investigators have begun to evaluate the interaction of the genetics of the foal with R. equi. This review describes past efforts to understand the genetic basis underlying R. equi susceptibility and tolerance. It also highlights the genetic technology available to study horses and describes the use of this technology in investigating R. equi. This review provides readers with a foundational understanding of candidate gene approaches, single nucleotide polymorphism-based, and copy number variant-based genome-wide association studies, and next generation sequencing (both DNA and RNA).
Topics: Actinomycetales Infections; Animals; Genetic Predisposition to Disease; Horse Diseases; Horses; Rhodococcus equi
PubMed: 26340305
DOI: 10.1111/jvim.13616 -
Acta Biochimica Polonica 2014Rhodococcus equi is an important etiologic agent of respiratory- and non-respiratory tract infections, diseases of animals and humans. Therapy includes the use of... (Review)
Review
Rhodococcus equi is an important etiologic agent of respiratory- and non-respiratory tract infections, diseases of animals and humans. Therapy includes the use of various group of chemotherapeutic agents, however resistance acquirement is quite common. To date there is no preferred treatment protocol for infections caused by isolates resistant to macrolides and rifampicin. The resistance acquirement is a result of many molecular mechanisms, some of which include alterations in the cell envelope composition and structure, activity of the efflux pumps, enzymatic destruction or inactivation of antibiotics, and changes in the target site. This paper contains an overview of antimicrobial susceptibility of R. equi, and explains the possible molecular mechanisms responsible for antimicrobial resistance in this particular microorganism.
Topics: Animals; Anti-Infective Agents; Humans; Microbial Sensitivity Tests; Models, Biological; Rhodococcus equi
PubMed: 25371917
DOI: No ID Found -
Emerging Infectious Diseases Sep 2022A multidrug-resistant clone of the animal and human pathogen Rhodococcus equi, MDR-RE 2287, has been circulating among equine farms in the United States since the 2000s....
A multidrug-resistant clone of the animal and human pathogen Rhodococcus equi, MDR-RE 2287, has been circulating among equine farms in the United States since the 2000s. We report the detection of MDR-RE 2287 outside the United States. Our finding highlights the risk for MDR-RE spreading internationally with horse movements.
Topics: Actinomycetales Infections; Animals; Anti-Bacterial Agents; Drug Resistance, Bacterial; Horse Diseases; Horses; Humans; Macrolides; Rhodococcus equi; Rifampin; United States
PubMed: 35997496
DOI: 10.3201/eid2809.220222 -
Microorganisms Dec 2022Bisphenol A (BPA) pollution poses an increasingly serious problem. BPA has been detected in a variety of environmental media and human tissues. Microbial degradation is...
Bisphenol A (BPA) pollution poses an increasingly serious problem. BPA has been detected in a variety of environmental media and human tissues. Microbial degradation is an effective method of environmental BPA remediation. However, BPA is also biotoxic to microorganisms. In this study, DSSKP-R-001 (R-001) was used to degrade BPA, and the effects of BPA on the growth metabolism, gene expression patterns, and toxicity-resistance mechanisms of were analyzed. The results showed that R-001 degraded 51.2% of 5 mg/L BPA and that 40 mg/L BPA was the maximum BPA concentration tolerated by strain R-001. Cytochrome P450 monooxygenase and multicopper oxidases played key roles in BPA degradation. However, BPA was toxic to strain R-001, exhibiting nonlinear inhibitory effects on the growth and metabolism of this bacterium. R-001 bacterial biomass, total protein content, and ATP content exhibited V-shaped trends as BPA concentration increased. The toxic effects of BPA included the downregulation of R-001 genes related to glycolysis/gluconeogenesis, pentose phosphate metabolism, and glyoxylate and dicarboxylate metabolism. Genes involved in aspects of the BPA-resistance response, such as base excision repair, osmoprotectant transport, iron-complex transport, and some energy metabolisms, were upregulated to mitigate the loss of energy associated with BPA exposure. This study helped to clarify the bacterial mechanisms involved in BPA biodegradation and toxicity resistance, and our results provide a theoretical basis for the application of strain R-001 in BPA pollution treatments.
PubMed: 36677360
DOI: 10.3390/microorganisms11010067