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2.
Int J Mol Sci ; 23(6)2022 Mar 18.
Article in English | MEDLINE | ID: covidwho-1765734

ABSTRACT

Corynebacterium diphtheriae, the etiological agent of diphtheria, is a re-emerging pathogen, responsible for several thousand deaths per year. In addition to diphtheria, systemic infections, often by non-toxigenic strains, are increasingly observed. This indicates that besides the well-studied and highly potent diphtheria toxin, various other virulence factors may influence the progression of the infection. This review focuses on the known components of C. diphtheriae responsible for adhesion, invasion, inflammation, and cell death, as well as on the cellular signaling pathways activated upon infection.


Subject(s)
Corynebacterium diphtheriae , Diphtheria , Corynebacterium , Diphtheria/microbiology , Diphtheria Toxin , Humans , Virulence Factors
3.
Jpn J Infect Dis ; 75(2): 202-204, 2022 Mar 24.
Article in English | MEDLINE | ID: covidwho-1761197

ABSTRACT

Many studies have been conducted on ventilator-associated complications (VACs) in patients with coronavirus 2019 (COVID-19). However, in these studies, the causative organisms were similar, and there were no reports on VAC corresponding with Corynebacteria. Coryneforms are frequently cultured in cases of polymicrobial infections and are usually considered contaminants in respiratory specimens. However, Corynebacterium pseudodiphtheriticum or C. striatum is known to be a pathogen in lower respiratory tract infections. We report three cases of VAC, probably due to C. pseudodiphtheriticum, in patients with COVID-19. If purulent lower respiratory tract specimens showed coryneform predominantly upon Gram staining, empirical therapy should be started. Furthermore, species identification and drug susceptibility testing should be performed.


Subject(s)
COVID-19 , Coinfection , Corynebacterium Infections , Mycobacterium tuberculosis , Coinfection/complications , Corynebacterium , Corynebacterium Infections/complications , Corynebacterium Infections/diagnosis , Humans , Microbial Sensitivity Tests , Respiration, Artificial/adverse effects
4.
Klin Lab Diagn ; 66(11): 673-677, 2021 Nov 29.
Article in English | MEDLINE | ID: covidwho-1626175

ABSTRACT

Corynebacterium spp. It is associated with inflammatory diseases of the respiratory tract (tracheitis, pharyngitis, rhinosinusitis, bronchitis, pneumonia, etc.). C. pseudodiphtheriticum can be the causative agent of bacterial coinfection in patients with a new coronavirus infection (COVID-19). The aim is to determine the pathogenic properties and resistance to antimicrobial drugs of Corynebacterium spp. strains to establish their etiological significance in the development of inflammatory diseases of the respiratory tract. Strains of Corynebacterium spp. isolated from patients with inflammatory diseases of the respiratory tract (43 pcs.) and practically healthy individuals (29 pcs.). Isolates were identified by mass spectrometric method (MALDI-TOF MS), their cytopathic effect in CHO-K1 cell culture, hemolytic, urease activity, antimicrobial drug resistance were determined. Strains of Corynebacterium spp. isolated from patients in the amount of 105 CFU/ml or more, practically healthy - 104 CFU/ml or less. Isolates of Corynebacterium spp. patients had a more pronounced cytopathic effect (83.7±11.1%) and were more often resistant to antimicrobial drugs than those isolated from practically healthy. To establish the etiological significance of Corynebacterium spp. isolates. in the development of inflammatory diseases of the respiratory tract, it is advisable to determine their amount in biological material (105 CFU/ml or more), the cytopathic effect on CHO-K1 cell culture, as well as the presence of multiple resistance to antimicrobial drugs. Differences in the characteristics of Corynebacterium spp. isolates. from patients with respiratory tract pathology and practically healthy individuals are associated with the strain, not the species, of corynebacteria.


Subject(s)
COVID-19 , Corynebacterium Infections , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Corynebacterium , Humans , Respiratory System , SARS-CoV-2
5.
Genome Med ; 13(1): 182, 2021 11 17.
Article in English | MEDLINE | ID: covidwho-1523323

ABSTRACT

BACKGROUND: Clinical metagenomics (CMg) has the potential to be translated from a research tool into routine service to improve antimicrobial treatment and infection control decisions. The SARS-CoV-2 pandemic provides added impetus to realise these benefits, given the increased risk of secondary infection and nosocomial transmission of multi-drug-resistant (MDR) pathogens linked with the expansion of critical care capacity. METHODS: CMg using nanopore sequencing was evaluated in a proof-of-concept study on 43 respiratory samples from 34 intubated patients across seven intensive care units (ICUs) over a 9-week period during the first COVID-19 pandemic wave. RESULTS: An 8-h CMg workflow was 92% sensitive (95% CI, 75-99%) and 82% specific (95% CI, 57-96%) for bacterial identification based on culture-positive and culture-negative samples, respectively. CMg sequencing reported the presence or absence of ß-lactam-resistant genes carried by Enterobacterales that would modify the initial guideline-recommended antibiotics in every case. CMg was also 100% concordant with quantitative PCR for detecting Aspergillus fumigatus from 4 positive and 39 negative samples. Molecular typing using 24-h sequencing data identified an MDR-K. pneumoniae ST307 outbreak involving 4 patients and an MDR-C. striatum outbreak involving 14 patients across three ICUs. CONCLUSION: CMg testing provides accurate pathogen detection and antibiotic resistance prediction in a same-day laboratory workflow, with assembled genomes available the next day for genomic surveillance. The provision of this technology in a service setting could fundamentally change the multi-disciplinary team approach to managing ICU infections. The potential to improve the initial targeted treatment and rapidly detect unsuspected outbreaks of MDR-pathogens justifies further expedited clinical assessment of CMg.


Subject(s)
COVID-19/pathology , Cross Infection/transmission , Metagenomics , Anti-Bacterial Agents/therapeutic use , COVID-19/virology , Coinfection/drug therapy , Coinfection/microbiology , Corynebacterium/genetics , Corynebacterium/isolation & purification , Cross Infection/microbiology , DNA, Bacterial/chemistry , DNA, Bacterial/metabolism , Drug Resistance, Multiple, Bacterial/genetics , Female , Humans , Intensive Care Units , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/isolation & purification , Male , Middle Aged , Polymorphism, Single Nucleotide , SARS-CoV-2/isolation & purification , Sequence Analysis, DNA , beta-Lactamases/genetics
8.
BMJ Case Rep ; 14(6)2021 Jun 11.
Article in English | MEDLINE | ID: covidwho-1266368

ABSTRACT

We describe a unique case of a patient with acute myeloid leukaemia (AML), with recurring infections during chemotherapy from chronic nasal carriage of non-diphtherial Corynebacterium, who was eventually diagnosed as she presented with neutropaenic sepsis. Identifying (often multiple) sources of infection in immunocompromised patients is crucial but deciding whether multiple organisms, which in health are considered as commensals, are actually pathogenic during vulnerable states-can be clinically difficult. Our case highlights the efforts to correctly identify the actual source of this rare organism and the recognition of its pathogenic potential when other illnesses present. We also review the literature of Corynebacteria in patients with haematological malignancies but believe this is the first case of AML to be infected with Corynebacterium presenting during the COVID-19 pandemic with a probable incidental positive swab for SARS-CoV-2.


Subject(s)
Bacteremia , COVID-19 , Bacteremia/diagnosis , Bacteremia/drug therapy , Corynebacterium , Female , Humans , Immunocompromised Host , Neoplasm Recurrence, Local , Pandemics , SARS-CoV-2
9.
A A Pract ; 14(9): e01287, 2020 Jul.
Article in English | MEDLINE | ID: covidwho-992616

ABSTRACT

Methemoglobinemia is a rare disorder of the blood in which there is an increase in methemoglobin, which occurs when hemoglobin is present in the oxidized form. Methemoglobin impairs hemoglobin's ability to transport oxygen, produces functional anemia, and leads to tissue hypoxia. We report the successful management of a case of refractory hypoxia due to acutely acquired methemoglobinemia in a patient undergoing treatment for coronavirus disease 2019 (COVID-19) pneumonia. The cause of methemoglobinemia in this patient remains unknown. Hypoxia and methemoglobinemia did not respond to methylene blue and required administration of packed red blood cell transfusions.


Subject(s)
Coronavirus Infections/complications , Hypoxia/etiology , Methemoglobinemia/complications , Pneumonia, Viral/complications , Respiratory Insufficiency/etiology , Acute Kidney Injury/complications , Acute Kidney Injury/therapy , Aged , Antibodies, Monoclonal, Humanized/therapeutic use , Antioxidants/therapeutic use , Ascorbic Acid/therapeutic use , Betacoronavirus , COVID-19 , Coronavirus Infections/drug therapy , Corynebacterium , Corynebacterium Infections/complications , Corynebacterium Infections/therapy , Cytokine Release Syndrome/complications , Enzyme Inhibitors/therapeutic use , Erythrocyte Transfusion , Hematinics/therapeutic use , Humans , Hydroxocobalamin/therapeutic use , Hydroxychloroquine/therapeutic use , Hypoxia/therapy , Male , Methemoglobinemia/therapy , Methylene Blue/therapeutic use , Pandemics , Pneumonia, Bacterial/complications , Pneumonia, Bacterial/therapy , Pneumonia, Viral/drug therapy , Renal Replacement Therapy , Respiratory Insufficiency/therapy , SARS-CoV-2 , Shock, Septic/complications
10.
Vaccine ; 38(48): 7581-7584, 2020 11 10.
Article in English | MEDLINE | ID: covidwho-845859

ABSTRACT

Today, Coronavirus Disease 2019 (COVID-19) is a global public health emergency and vaccination measures to counter its diffusion are deemed necessary. Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the etiological agent of the disease, unleashes a T-helper 2 immune response in those patients requiring intensive care. Here, we illustrate the immunological mechanism to train the immune system towards a more effective and less symptomatic T-helper 1 immune response, to be exploited against SARS-CoV-2.


Subject(s)
BCG Vaccine/administration & dosage , Bacterial Vaccines/administration & dosage , Betacoronavirus/immunology , Coronavirus Infections/prevention & control , Immunity, Innate/drug effects , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Propionibacteriaceae/immunology , Betacoronavirus/drug effects , Betacoronavirus/pathogenicity , COVID-19 , COVID-19 Vaccines , Coronavirus Infections/epidemiology , Coronavirus Infections/immunology , Coronavirus Infections/virology , Corynebacterium , Humans , Immunization Schedule , Immunogenicity, Vaccine , Interleukins/genetics , Interleukins/immunology , Patient Safety , Pneumonia, Viral/epidemiology , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , SARS-CoV-2 , Th1 Cells/drug effects , Th1 Cells/immunology , Th1 Cells/virology , Th1-Th2 Balance/drug effects , Th2 Cells/drug effects , Th2 Cells/immunology , Th2 Cells/virology , Vaccination , Viral Vaccines/administration & dosage , Viral Vaccines/biosynthesis
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