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1.
Sex Transm Infect ; 100(2): 63-69, 2024 Feb 19.
Article in English | MEDLINE | ID: mdl-38071543

ABSTRACT

BACKGROUND AND OBJECTIVES: The diagnosis of neurosyphilis (NS) lacks a true 'gold standard', making the diagnosis challenging while consequences of a misdiagnosis are potentially severe. The aim of this study was to evaluate the diagnostic performance of measuring an antibody index (AI) for the intrathecal synthesis of specific anti-Treponema pallidum (T. pallidum) IgG for the diagnosis of NS. METHODS: Specific anti-T. pallidum IgG were measured simultaneously in paired cerebrospinal fluid (CSF)-serum samples collected retrospectively and prospectively between 2007 and 2022, from patients suspected of NS, in Switzerland. An AI was calculated to account for blood-brain barrier integrity. Area under the receiver operating characteristic curve, sensitivity/specificity and positive/negative predictive values of AI test were estimated. Two NS definitions were used: NS1 included patients with NS suspicion presenting with neurological symptoms and/or acute neurosensory signs, and positive T. Pallidum Hemagglutinations Assay (TPHA)/T. pallidum particle agglutination assay (TPPA) serology and CSF-TPHA/TPPA ≥320, and either CSF-leucocytes >5 cells/mm3 and/or CSF-protein >0.45 g/L and/or a reactive CSF-venereal disease research laboratory (VDRL)/rapid plasma reagin (RPR) test. NS2 included patients with suspected NS presenting with acute ocular and/or otologic symptoms, and positive TPHA/TPPA serology, and a favourable response to NS treatment. Controls were patients diagnosed with any other central nervous system (CNS) pathologies and with positive TPHA/TPPA serology. RESULTS: The study included 71 NS (43 NS1 and 28 NS2) and 110 controls. With a threshold of ≥1.7, sensitivity and specificity of the specific AI test were 90.7% (CI 77.7 to 97.4) and 100% (CI 96.7 to 100.0), respectively, for NS1 and 14.3% (CI 4 to 32.7) and 100% (CI 96.7 to 100.0) for NS2. In patients suspected of NS with a CNS involvement (NS1 group), NS could be confirmed by the positivity of this specific AI. CONCLUSIONS: Measurement of an intrathecal synthesis index of specific anti-T. pallidum IgG in patients with CSF inflammatory signs appears to be a valuable diagnostic test. However, in otic or ocular syphilis, presenting few CSF abnormalities, AI is not sufficient alone to confirm NS diagnosis. TRIAL REGISTRATION: Swiss Association of Research Ethics Committees number 2019-00232.


Subject(s)
Neurosyphilis , Syphilis , Humans , Case-Control Studies , Retrospective Studies , Globus Pallidus , Neurosyphilis/cerebrospinal fluid , Immunoglobulin G , Antibodies, Bacterial , Biomarkers
2.
Infection ; 52(3): 1165-1169, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38480644

ABSTRACT

In the last 10 years, an increase in tularemia cases has been observed in both humans and animals in Switzerland. In these, infection with Francisella tularensis, the causative agent of the zoonotic disease tularemia, can occur through arthropod vectors or contact to infected animals or exposure to contaminated environmental sources. Currently, we are only able to postulate potential aetiologies: (i) behavioral changes of humans with more exposure to endemic habitats of infected arthropod vectors; (ii) an increased rate of tularemia infected ticks; (iii) increasing number and geographical regions of tick biotopes; (iv) increasing and/or more diverse reservoir populations; (v) increasing presence of bacteria in the environment; (vi) raised awareness and increased testing among physicians; (vii) improved laboratory techniques including molecular testing. To approach these questions, a one-health strategy is necessary. A functioning collaboration between public health, human medicine, and diagnostic and veterinary units for the control of tularemia must be established. Furthermore, the public should be included within citizen-supported-science-projects.


Subject(s)
Francisella tularensis , One Health , Tularemia , Tularemia/epidemiology , Tularemia/transmission , Tularemia/diagnosis , Switzerland/epidemiology , Humans , Animals , Zoonoses/transmission , Zoonoses/epidemiology , Zoonoses/microbiology , Ticks/microbiology , Arthropod Vectors/microbiology
3.
Rev Med Suisse ; 18(777): 724-728, 2022 Apr 13.
Article in French | MEDLINE | ID: mdl-35417102

ABSTRACT

Since the introduction of antibiotics, successive waves of Staphylococcus aureus clones occurred, each one having characteristic susceptibility pattern to antibiotics and virulence factors. We report here the results of a molecular epidemiological surveillance of methicillin-resistant S. aureus (MRSA) in French-speaking Switzerland between 2006 and 2020 showing the emergence and disappearance of clones known for their international dissemination, and the sporadic appearance of other international clones. Since 2012, a marked decrease in the incidence of cases attributable to the biology of the clones and to the control measures taken in the hospitals has been observed. These results highlight the importance of continuous surveillance in order to better assess the burden of this multi-resistant pathogen in our region.


Depuis l'introduction des antibiotiques, des vagues successives de clones de Staphylococcus aureus sont apparues, chacun avec un profil de susceptibilité aux antibiotiques et de virulence caractéristique. Nous rapportons ici les résultats d'une surveillance épidémiologique moléculaire de S. aureus résistant à la méticilline (MRSA) en Suisse romande entre 2006 et 2020 montrant l'émergence et la disparition de clones connus pour leur dissémination internationale, ainsi que l'apparition sporadique d'autres clones internationaux. Depuis 2012, une diminution marquée de l'incidence des cas attribuable à la biologie des clones et aux mesures de contrôle prises dans les hôpitaux est observée. Ces résultats nous montrent l'importance d'une surveillance continue afin de mieux évaluer le fardeau que représente ce germe multirésistant dans notre région.


Subject(s)
Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Humans , Methicillin-Resistant Staphylococcus aureus/genetics , Microbial Sensitivity Tests , Molecular Epidemiology , Staphylococcal Infections/drug therapy , Staphylococcal Infections/epidemiology , Switzerland/epidemiology
4.
Int J Syst Evol Microbiol ; 70(5): 3577-3581, 2020 May.
Article in English | MEDLINE | ID: mdl-32320380

ABSTRACT

Rejection (nomen rejiciendum) of the name Borreliella and all new combinations therein is being requested on grounds of risk to human health and patient safety (Principle 1, subprinciple 2 and Rule 56a) and violation to aim for stability of names, to avoid useless creation of names (Principle 1, subprinciple 1 and 3) and that names should not be changed without sufficient reason (Principle 9 of the International Code of Nomenclature of Prokaryotes).


Subject(s)
Phylogeny , Spirochaetales/classification , Terminology as Topic
5.
Anaerobe ; 64: 102220, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32531434

ABSTRACT

Of 69 clinical isolates of Finegoldia magna tested, 36% presented high-level MICs of erythromycin (>256 µg/ml), harboring erm(A) (n = 20) or erm(B) (n=5). Of nine isolates exhibiting an inducible resistance phenotype to macrolides-lincosamides-streptogramins B, four (44%) were susceptible with a potential risk of treatment failure due to emergence of resistant mutants.


Subject(s)
Drug Resistance, Multiple, Bacterial/genetics , Firmicutes/drug effects , Firmicutes/genetics , Lincosamides/pharmacology , Macrolides/pharmacology , Methyltransferases/genetics , Streptogramins/pharmacology , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , DNA, Bacterial/genetics , Female , Firmicutes/isolation & purification , Gram-Positive Bacterial Infections/diagnosis , Gram-Positive Bacterial Infections/microbiology , Humans , Male , Middle Aged , RNA, Ribosomal, 23S/genetics , Young Adult
6.
J Infect Dis ; 219(7): 1138-1145, 2019 03 15.
Article in English | MEDLINE | ID: mdl-30325448

ABSTRACT

BACKGROUND: The increased prevalence of syphilis in Cuba prompted us to map the circulating Treponema pallidum subsp. pallidum allelic profiles in this geographic region. METHODS: Samples were collected from 2012 to 2017, from 83 male patients with ulcers or skin lesions, and were examined using multilocus sequence typing. Additionally, we analyzed the 23S rDNA and 16S rDNA regions for the presence of possible mutations leading to macrolide and tetracycline resistance. RESULTS: Among 94% of fully typed strains, we found 7 different allelic profiles, of which 4 had not been previously described. More than 87% of patients were infected with the T. pallidum SS14-like group and only 8.2% with T. pallidum Nichols-like group. As in other countries, the 1.3.1 allelic profile (ie, SS14-like) was the most common. In addition, 1 of the newly described allelic profiles represents T. pallidum strains that arose by recombination events between members of different T. pallidum subgroups. More than 90% of patients were infected with treponemes harboring the A2058G mutation. However, we found no potential tetracycline-resistant T. pallidum mutations. CONCLUSIONS: Our results suggest that, in Cuba, tetracycline antibiotics could be used to treat syphilis in penicillin-allergic patients instead of macrolides.


Subject(s)
Syphilis/microbiology , Treponema pallidum/classification , Treponema pallidum/genetics , Adult , Alleles , Anti-Bacterial Agents , Bacterial Typing Techniques , Cuba , Drug Resistance, Bacterial/genetics , Humans , Macrolides/therapeutic use , Male , Multilocus Sequence Typing , Mutation , Syphilis/drug therapy , Tetracycline/therapeutic use
7.
Rev Med Suisse ; 16(688): 629-634, 2020 Apr 01.
Article in French | MEDLINE | ID: mdl-32239836

ABSTRACT

Lyme borreliosis is a frequent disease in Switzerland. Due to the increasing number of symptoms attributed to this infection, the diagnostic is often controversy between different specialists and is often a subject of discussion. The diagnostic of Lyme disease lays particularly on the knowledge of cutaneous signs which are the only specific. Despite recent scientific progress, microbiological diagnostic is still delicate and serological tests currently used do not differentiate between an active infection versus a serological marker. Here we describe the different clinical presentations of Lyme disease diagnosis and management procedures according to stages of evolution.


La borréliose de Lyme est une maladie fréquente en Suisse. Elle a beaucoup fait parler d'elle ces dernières années en raison d'un nombre croissant de symptômes qui lui ont été attribués, faisant polémique auprès des spécialistes. Le diagnostic de la maladie de Lyme repose en grande partie sur la reconnaissance des signes cutanés qui seuls sont spécifiques. Malgré les progrès scientifiques, le diagnostic microbiologique reste toujours délicat, et les tests sérologiques utilisés actuellement ne permettent pas de faire la distinction entre une infection active et une cicatrice sérologique. Dans cet article, nous décrivons les différentes manifestations cliniques et la prise en charge diagnostique et thérapeutique selon les stades d'évolution de la maladie.


Subject(s)
Dermatology/methods , Lyme Disease/diagnosis , Lyme Disease/therapy , Humans , Lyme Disease/epidemiology , Serologic Tests , Switzerland/epidemiology
8.
Emerg Infect Dis ; 25(6): 1084-1092, 2019 06.
Article in English | MEDLINE | ID: mdl-31107229

ABSTRACT

A recent hospital outbreak related to premoistened gloves used to wash patients exposed the difficulties of defining Burkholderia species in clinical settings. The outbreak strain displayed key B. stabilis phenotypes, including the inability to grow at 42°C; we used whole-genome sequencing to confirm the pathogen was B. stabilis. The outbreak strain genome comprises 3 chromosomes and a plasmid, sharing an average nucleotide identity of 98.4% with B. stabilis ATCC27515 BAA-67, but with 13% novel coding sequences. The genome lacks identifiable virulence factors and has no apparent increase in encoded antimicrobial drug resistance, few insertion sequences, and few pseudogenes, suggesting this outbreak was an opportunistic infection by an environmental strain not adapted to human pathogenicity. The diversity among outbreak isolates (22 from patients and 16 from washing gloves) is only 6 single-nucleotide polymorphisms, although the genome remains plastic, with large elements stochastically lost from outbreak isolates.


Subject(s)
Burkholderia Infections/epidemiology , Burkholderia Infections/microbiology , Burkholderia/genetics , Genome, Bacterial , Burkholderia/cytology , Burkholderia/metabolism , Cross Infection/epidemiology , Cross Infection/microbiology , Fatty Acids/chemistry , Fatty Acids/metabolism , Humans , Switzerland/epidemiology
9.
Appl Environ Microbiol ; 85(3)2019 02 01.
Article in English | MEDLINE | ID: mdl-30478230

ABSTRACT

Using bacteria to transform reactive corrosion products into stable compounds represents an alternative to traditional methods employed in iron conservation. Two environmental Aeromonas strains (CA23 and CU5) were used to transform ferric iron corrosion products (goethite and lepidocrocite) into stable ferrous iron-bearing minerals (vivianite and siderite). A genomic and transcriptomic approach was used to analyze the metabolic traits of these strains and to evaluate their pathogenic potential. Although genes involved in solid-phase iron reduction were identified, key genes present in other environmental iron-reducing species are missing from the genome of CU5. Several pathogenicity factors were identified in the genomes of both strains, but none of these was expressed under iron reduction conditions. Additional in vivo tests showed hemolytic and cytotoxic activities for strain CA23 but not for strain CU5. Both strains were easily inactivated using ethanol and heat. Nonetheless, given a lesser potential for a pathogenic lifestyle, CU5 is the most promising candidate for the development of a bio-based iron conservation method stabilizing iron corrosion. Based on all the results, a prototype treatment was established using archaeological items. On those, the conversion of reactive corrosion products and the formation of a homogenous layer of biogenic iron minerals were achieved. This study shows how naturally occurring microorganisms and their metabolic capabilities can be used to develop bio-inspired solutions to the problem of metal corrosion.IMPORTANCE Microbiology can greatly help in the quest for a sustainable solution to the problem of iron corrosion, which causes important economic losses in a wide range of fields, including the protection of cultural heritage and building materials. Using bacteria to transform reactive and unstable corrosion products into more-stable compounds represents a promising approach. The overall aim of this study was to develop a method for the conservation and restoration of corroded iron items, starting from the isolation of iron-reducing bacteria from natural environments. This resulted in the identification of a suitable candidate (Aeromonas sp. strain CU5) that mediates the formation of desirable minerals at the surfaces of the objects. This led to the proof of concept of an application method on real objects.


Subject(s)
Aeromonas/metabolism , Ferric Compounds/metabolism , Iron Compounds/metabolism , Iron/metabolism , Minerals/metabolism , Aeromonas/genetics , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Biodegradation, Environmental , Corrosion , Genome, Bacterial , Iron/chemistry , Oxidation-Reduction
10.
J Clin Microbiol ; 53(8): 2703-5, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25994161

ABSTRACT

From 2008 to 2013, 39 Helcococcus kunzii strains were collected from human clinical specimens (79% from foot ulcers), and 85% of the 39 patients were infected. Matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry and molecular methods accurately identified all isolates. This large study of clinical observations confirms the potential pathogenic role of H. kunzii.


Subject(s)
Bacteriological Techniques/methods , Firmicutes/classification , Firmicutes/isolation & purification , Gram-Positive Bacterial Infections/epidemiology , Gram-Positive Bacterial Infections/microbiology , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Adult , Aged , Aged, 80 and over , Anti-Bacterial Agents/therapeutic use , Female , Firmicutes/chemistry , Gram-Positive Bacterial Infections/pathology , Humans , Male , Middle Aged , Young Adult
11.
Ann Emerg Med ; 66(1): 60-4, 2015 Jul.
Article in English | MEDLINE | ID: mdl-25728308

ABSTRACT

Nervous system involvement in Lyme disease often mimics other conditions and thus represents a diagnostic challenge, especially in an emergency department setting. We report a case of a female teenager presenting with sudden-onset aphasia and transient right-sided faciobrachial hemiplegia, along with headache and agitation. Ischemia, vasculitis, or another structural lesion was excluded by brain imaging. Toxicologic evaluation results were negative. Cerebral perfusion computed tomography and electroencephalography showed left parietotemporal brain dysfunction. Lumbar puncture result, although atypical, suggested bacterial infection and intravenous ceftriaxone was initiated. Finally, microbiological cerebrospinal fluid analysis revealed Lyme neuroborreliosis, showing specific intrathecal antibody production and high level of C-X-C motif chemokine 13. The patient rapidly recovered. To our knowledge, this report for the first time illustrates that acute-onset language and motor symptoms may be directly related to Lyme neuroborreliosis. Neuroborreliosis may mimic other acute neurologic events such as stroke and should be taken into diagnostic consideration even in the absence of classic symptoms and evolution.


Subject(s)
Aphasia/etiology , Lyme Neuroborreliosis/diagnosis , Paresis/etiology , Adolescent , Brain/diagnostic imaging , Brain/physiopathology , Diagnosis, Differential , Electroencephalography , Emergency Service, Hospital , Female , Humans , Lyme Neuroborreliosis/complications , Lyme Neuroborreliosis/diagnostic imaging , Lyme Neuroborreliosis/physiopathology , Neuroimaging , Tomography, X-Ray Computed
12.
J Antimicrob Chemother ; 69(8): 2056-60, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24710027

ABSTRACT

OBJECTIVES: Actinobaculum schaalii is a Gram-positive bacillus increasingly reported as a causative agent of urinary tract infections as well as invasive infections, mainly in the elderly and patients with underlying urological conditions. Since little is known about the molecular basis of antimicrobial resistance in A. schaalii, the aim of this study was to investigate resistance to macrolides, lincosamides and streptogramins (MLS) in this emerging pathogen. METHODS: A total of 32 A. schaalii clinical isolates from France and Switzerland were studied. MICs of erythromycin, spiramycin, lincomycin, clindamycin and quinupristin/dalfopristin were determined by the agar dilution method. Resistance genes erm(A), erm(B), erm(C), erm(F), erm(G), erm(X), msr(A) and mef(A) were screened by PCR. The genetic environment was determined by random cloning and PCR mapping. RESULTS: Out of 32 isolates tested, 21 were highly resistant to erythromycin, spiramycin, lincomycin and clindamycin (MICs >256 mg/L), whereas 11 exhibited low MICs (MICs < 0.12 mg/L). On the other hand, quinupristin/dalfopristin remained active against all the isolates. An inducible MLSB resistance phenotype was noted in all cases. The erm(X) gene was detected among all resistant strains, whereas none was detected in susceptible strains. Analysis of genetic support and environment revealed that erm(X) was probably part of the chromosome of A. schaalii. CONCLUSIONS: This study is the first molecular characterization of MLS resistance in A. schaalii. In all cases, it was due to the presence of erm(X), a methylase gene previously identified in other clinically relevant Gram-positive bacilli.


Subject(s)
Actinomycetaceae/drug effects , Anti-Bacterial Agents/pharmacology , Bacterial Proteins/genetics , Drug Resistance, Multiple, Bacterial/genetics , Methyltransferases/genetics , Actinomycetaceae/genetics , Actinomycetaceae/isolation & purification , Humans , Lincosamides/pharmacology , Macrolides/pharmacology , Microbial Sensitivity Tests , Molecular Sequence Data , Streptogramins/pharmacology , Urinary Tract Infections/drug therapy , Urinary Tract Infections/microbiology
13.
Int J Antimicrob Agents ; : 107241, 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38942247

ABSTRACT

BACKGROUND: Bacteroides fragilis is the most frequent cause of anaerobic bacteraemia. Although recent data suggest a rise in antimicrobial resistance (AMR) of this and other anaerobic bacteria, surveillance remains limited due to a lack of both data availability and comparability. However, a newly introduced standardised method for antimicrobial susceptibility testing (AST) of anaerobic bacteria has made larger scale surveillance possible for the first time. AIM: To investigate phenotypic AMR of Bacteroides fragilis isolates from bacteraemia across Europe in 2022. METHODS: In a multicentre approach, clinical microbiology laboratories in Europe were invited to contribute results of AST for Bacteroides fragilis blood culture isolates (including only the first isolate per patient and year). AST of a selection of four antibiotics was performed locally by participating laboratories in a prospective or retrospective manner, using the new EUCAST disc diffusion method on fastidious anaerobe agar (FAA-HB). RESULTS: A total of 16 European countries reported antimicrobial susceptibilities in 449 unique isolates of Bacteroides fragilis from blood cultures in 2022. Clindamycin demonstrated the highest resistance rates (20.9%, range 0 - 63.6%), followed by piperacillin-tazobactam (11.1%, 0 - 54.5%), meropenem (13.4%, 0 - 45.5%), and metronidazole (1.8%, 0 - 20.0%), all with wide variation between countries. CONCLUSION: Considering that the mean resistance rates across Europe were higher than expected for three of the four anti-anaerobic antibiotics under surveillance, both local AST of clinically relevant isolates of Bacteroides fragilis and continued surveillance on an international level is warranted.

16.
Clin Microbiol Infect ; 29(12): 1603.e1-1603.e4, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37611864

ABSTRACT

OBJECTIVES: Serological tests for syphilis detect mainly total Ig, IgM or IgG antibodies. We aimed to evaluate the specific IgA response in syphilis patients according to disease stage. METHODS: A serum IgA-enzyme immunoassay was developed using commercially available microplates coated with recombinant treponemal antigens and an anti-IgA-conjugate. To define a cut-off, we used 91 syphilis positive and 136 negative sera previously defined by the rapid plasma reagin and the Treponema pallidum particle agglutination results. Then we determined the intra- and inter-assay precisions, diagnostic sensitivity according to the clinical stage (in 66, 55 and 42 sera from primary, secondary and latent syphilis patients, respectively) and specificity (in 211 sera from people with conditions different to syphilis). IgA values were further measured in 71 sera from patients with previously treated syphilis. RESULTS: The newly developed IgA-enzyme immunoassay showed a good discrimination between negative and positive samples with intra- and inter-assay variation coefficients <20%. The sensitivity was 80.3% (95% CI, 70.0-90.6), 100.0% (95% CI, 99.1-100.0) and 95.2% (95% CI, 87.6-100.0) in primary, secondary and latent syphilis, respectively, and the specificity was 98.1% (95% CI, 96.0-100.0). Further, IgA values were negative in 61.3% (38/62) of patients with previously treated syphilis. DISCUSSION: Our findings suggest serum IgA as a sensitive and specific marker of syphilis and its detection could be used as a screening assay for active infection. Further evaluation is needed in prospective longitudinal field studies.


Subject(s)
Syphilis , Treponema pallidum , Humans , Prospective Studies , Syphilis Serodiagnosis , Immunoglobulin A , Antibodies, Bacterial , Sensitivity and Specificity
17.
J Virol Methods ; 322: 114831, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37838083

ABSTRACT

Vaccine-induced protection against tick-borne encephalitis virus (TBEV) is mediated by antibodies to the viral particle/envelope protein. The detection of non-structural protein 1 (NS1) specific antibodies has been suggested as a marker indicative of natural infections. However, recent work has shown that TBEV vaccines contain traces of NS1, and immunization of mice induced low amounts of NS1-specific antibodies. In this study, we investigated if vaccination induces TBEV NS1-specific antibodies in humans. Healthy army members (n = 898) were asked to fill in a questionnaire relating to flavivirus vaccination or infection, and blood samples were collected. In addition, samples of 71 suspected acute TBE cases were included. All samples were screened for the presence of TBEV NS1-specific IgG antibodies using an in-house developed ELISA. Antibodies were quantified as percent positivity in reference to a positive control. For qualitative evaluation, cut-off for positivity was defined based on the mean OD of the lower 95% of the vaccinated individuals + 3 SD. We found significantly higher NS1-specific IgG antibody titers (i.e., quantitative evaluation) in individuals having received 2, 3, or 4 or more vaccine doses than in non-vaccinated individuals. Similarly, the percentage of individuals with a positive test result (i.e., qualitative evaluation) was higher in individuals vaccinated against tick-borne encephalitis than in unvaccinated study participants. Although NS1-specific IgG titers remained at a relatively low level when compared to TBE patients, a clear distinction was not always possible. Establishing a clear cut-off point in detection systems is critical for NS1-specific antibodies to serve as a marker for distinguishing the immune response after vaccination and infection.


Subject(s)
Encephalitis Viruses, Tick-Borne , Encephalitis, Tick-Borne , Flavivirus Infections , Viral Vaccines , Humans , Antibodies, Viral , Antibody Formation , Encephalitis, Tick-Borne/prevention & control , Immunoglobulin G , Vaccination
18.
Diagnostics (Basel) ; 13(18)2023 Sep 11.
Article in English | MEDLINE | ID: mdl-37761277

ABSTRACT

IVDR regulation represents a major challenge for diagnostic microbiology laboratories. IVDR complicates a broad range of aspects and poses a risk given the high diversity of pathogens (including rare but highly virulent microbes) and the large variety of samples submitted for analysis. The regular emergence of new pathogens (including Echovirus E-11, Adenovirus 41, Monkeypox virus, Alongshan virus, and Enterovirus D68, as recent examples in Europe in the post SARS-CoV-2 era) is another factor that makes IVDR regulation risky, because its detrimental effect on production of in-house tests will negatively impact knowledge and expertise in the development of new diagnostic tests. Moreover, such regulations negatively impact the availability of diagnostic tests, especially for neglected pathogens, and has a detrimental effect on the overall costs of the tests. The increased regulatory burden of IVDR may thereby pose an important risk for public health. Taken together, it will have a negative impact on the financial balance of diagnostic microbiology laboratories (especially small ones). The already-high standards of quality management of all ISO-accredited and Swissmedic-authorized laboratories render IVDR law of little value, at least in Switzerland, while tremendously increasing the regulatory burden and associated costs. Eventually, patients will need to pay for diagnostic assays outside of the framework of their insurance in order to obtain a proper diagnostic assessment, which may result in social inequity. Thus, based on the risk assessment outlined above, the coordinated commission for clinical microbiology proposes adjusting the IvDO ordinance by (i) introducing an obligation to be ISO 15189 accredited and (ii) not implementing the IvDO 2028 milestone.

19.
Clin Microbiol Infect ; 29(2): 190-199, 2023 Feb.
Article in English | MEDLINE | ID: mdl-35623578

ABSTRACT

OBJECTIVES: Matrix assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) is a widely used method for bacterial species identification. Incomplete databases and mass spectral quality (MSQ) still represent major challenges. Important proxies for MSQ are the number of detected marker masses, reproducibility, and measurement precision. We aimed to assess MSQs across diagnostic laboratories and the potential of simple workflow adaptations to improve it. METHODS: For baseline MSQ assessment, 47 diverse bacterial strains, which are challenging to identify by MALDI-TOF MS, were routinely measured in 36 laboratories from 12 countries, and well-defined MSQ features were used. After an intervention consisting of detailed reported feedback and instructions on how to acquire MALDI-TOF mass spectra, measurements were repeated and MSQs were compared. RESULTS: At baseline, we observed heterogeneous MSQ between the devices, considering the median number of marker masses detected (range = [2-25]), reproducibility between technical replicates (range = [55%-86%]), and measurement error (range = [147 parts per million (ppm)-588 ppm]). As a general trend, the spectral quality was improved after the intervention for devices, which yielded low MSQs in the baseline assessment as follows: for four out of five devices with a high measurement error, the measurement precision was improved (p-values <0.001, paired Wilcoxon test); for six out of ten devices, which detected a low number of marker masses, the number of detected marker masses increased (p-values <0.001, paired Wilcoxon test). DISCUSSION: We have identified simple workflow adaptations, which, to some extent, improve MSQ of poorly performing devices and should be considered by laboratories yielding a low MSQ. Improving MALDI-TOF MSQ in routine diagnostics is essential for increasing the resolution of bacterial identification by MALDI-TOF MS, which is dependent on the reproducible detection of marker masses. The heterogeneity identified in this external quality assessment (EQA) requires further study.


Subject(s)
Bacteria , Laboratories , Humans , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Reproducibility of Results , Workflow
20.
Clin Microbiol Infect ; 28(8): 1099-1104, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35289297

ABSTRACT

OBJECTIVES: Urinary culture sensitivity after antibiotics administration is unknown. This study aimed to describe the diagnostic sensitivity of urine cultures from patients' first, second, and third micturition samples after a single dose of empirical antibiotics given for upper and/or febrile urinary tract infections, as well as searched for factors influencing diagnostic sensitivity over time. METHODS: We collected consecutive urine samples from adult patients with an upper or febrile urinary tract infection diagnosed at four secondary hospital emergency rooms. One sample was collected before a first dose of empirical antibiotic treatment and up to three samples were collected from consecutive postadministration micturition. The main outcome was the number of positive cultures growing uropathogens with ≥103 colony forming units (CFUs) for men and ≥104 for women. Identical analyses were performed for any identified CFU and ≥105 CFU cut-off points. Time between antibiotic administration and first negative urinary culture was noted, which could have been at the time of any of the three postantibiotic urine samples. We used a Cox regression analysis for age- and sex-adjusted analyses. RESULTS: A total of 86 of 87 patients' preantibiotic cultures (99%) were positive compared with 26 of 75 (35%; p < 0.001), 15 of 50 (30%; p < 0.001), and 1 of 15 (7%; p < 0.001) of the first, second, and third postantibiotic samples, respectively, and missing 14 of 21 (67%), 13 of 17 (76%), and 7 of 7 (100%) of uropathogens with antibiotic resistance, respectively. The times needed for 25%, 50%, and 75% of cultures to be negative were 1.5, 2.9, and 9 hours, respectively, after antibiotic administration. Older age, male sex, non-Escherichia coli pathogens, urinary tract disease, comorbidity burdens, and urinary catheters prolonged time to negative culture, but were not significantly associated after adjustment. Uropathogens were found at ≥105 CFU in 15 of 75 (20%), 7 of 50 (14%), and 0 of 15 (0%) of the three postantibiotic micturition samples, respectively, and in any identified CFU in 48 of 75 (64%), 23 of 50 (46%), and 1 of 15 (7%), respectively. CONCLUSION: Urinary culture sensitivity decreases rapidly after administering antibiotics.


Subject(s)
Anti-Bacterial Agents , Urinary Tract Infections , Adult , Anti-Bacterial Agents/therapeutic use , Female , Humans , Male , Prospective Studies , Urinalysis , Urinary Tract Infections/diagnosis , Urinary Tract Infections/drug therapy , Urinary Tract Infections/microbiology
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