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1.
Klin Lab Diagn ; 67(6): 350-354, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35749600

RESUMO

The results of evaluating the effectiveness of the use of liquid transport media at the preanalytical stage of bacteriological diagnosis of diphtheria infection are presented. A typical toxigenic strain of C. diphtheriae biovar gravis № 665 was used. The experiments were carried out using a laboratory-prepared medium based on GRM-broth (State research center for applied biotechnology and microbiology, Obolensk), a transport system with a fleecy probe swab (DELTALAB) and a transport system ∑-Transwab ® with a polyurethane Sigma-swab (Medical Wire & Equipment Co. (Bath) Ltd.). The tampons were pooled with a 24-hour bacterial culture of C. diphtheriae, then immediately seeded on Tellurite-containing blood agar. Storage conditions were simulated for 6-24 hours: at room conditions +(20-25)° C, in the refrigerator +(4-8)° C, in a thermostat +(37±1)° C. Storage of C. diphtheriae was most optimal on two liquid transport systems in a refrigerator +(4-8)° C for 6 and 24 hours; in room conditions +(20-25)° C - there was a decrease in seeding after 6 hours and loss of pathological material after 24 hours, more pronounced on a fleecy probe swab; under thermostat conditions +(37±1)° C on both transport systems, a decrease in seeding was noted after 6 hours and a complete loss of pathological material after 24 hours. The results obtained demonstrated the efficiency of using the Amies liquid transport medium and justify the need to develop a domestic analogue of the transport system based on the Amies liquid medium for the bacteriological diagnosis of diphtheria infection.


Assuntos
Corynebacterium diphtheriae , Difteria , Corynebacterium , Meios de Cultura , Difteria/diagnóstico , Humanos , Manejo de Espécimes
2.
J Clin Microbiol ; 59(5)2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33139423

RESUMO

In light of the present pandemic of novel coronavirus disease 2019 (COVID-19) and the unprecedented high demand for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) testing worldwide, there are shortages of established specimen collection devices for respiratory viral testing for diagnostic microbiology laboratories. This creates the need to validate unverified collection devices from manufacturers that may not be a registered supplier for medical devices. As clinical laboratories do not routinely perform quality control of established collection devices, there is a need to have a systematic, robust approach to the assessment of substitute unregistered collection swabs and viral transport media (VTM). A discussion of the aspects requiring consideration when determining the suitability and implementation of new collection devices is presented. These specific assessment criteria include an inspection of device integrity, determination of swab and VTM sterility and in vitro performance, VTM stability, and examination of the clinical performance of the device. This method was used in a front-line medical microbiology laboratory on swabs and VTM from an unregistered manufacturer, with suboptimal results that precluded implementation. As the pandemic continues, it will be important for diagnostic laboratories to adopt a flexible and streamlined approach to maintaining adequate supply chains for testing reagents and materials.


Assuntos
Teste para COVID-19/instrumentação , COVID-19/diagnóstico , Manejo de Espécimes/instrumentação , Técnicas de Laboratório Clínico , Humanos , Pandemias , SARS-CoV-2
3.
J Med Virol ; 93(5): 2774-2781, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33128389

RESUMO

The reduced availability of commercial swabs and transport media for testing and administrative demands for increased testing capacity during the coronavirus disease 2019 (COVID-19) public health emergency has seriously challenged national laboratory testing programs, forcing many to use nontraditional collection devices, often without typical analytical assessment of their suitability in testing. Five common transport media (four commercial and one in-house) were evaluated for their suitability in the collection of nasopharyngeal swab specimens for subsequent molecular detection of severe acute respiratory syndrome-associated coronavirus 2 (SARS-CoV-2). Results suggest that these transport media provide dependable temporal stability of the SARS-CoV-2 virus without significant analytical interference of molecular assays. These findings are not only important for addressing critical laboratory supply chain shortages of transport media in the current COVID-19 health crisis but also for future pandemic planning, when again supplies of commercially available transport media might be depleted.


Assuntos
Teste para COVID-19 , COVID-19/diagnóstico , SARS-CoV-2/isolamento & purificação , Manejo de Espécimes/métodos , Meios de Cultura , Humanos , Nasofaringe/virologia , Manejo de Espécimes/instrumentação
4.
Virol J ; 18(1): 53, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33691737

RESUMO

INTRODUCTION: The sudden arrival of the COVID-19 pandemic placed significant stresses on supply chains including viral transport medium (VTM). The VTM that was urgently required needed to support viral replication, as well as other routine diagnostic approaches. We describe the preparation and validation testing of VTM for rapidly expanding diagnostic testing, where the capacity of the VTM to preserve viral integrity, for culture, isolation and full sequence analysis, was maintained. METHODS: VTM was prepared using different methods of sterilization then 'spiked' with virus. The VTM was investigated using viral culture in Vero cells, and for nucleic acid detection by quantitative PCR. RESULTS: The best results were obtained by filter and autoclave-based sterilization. The VTM proved robust for culture-based analyses provided the inoculated VTM was stored at 4 °C, and tested within 48 h. The filtered VTM also supported PCR-based diagnosis for at least 5 days when the mock inoculated VTM was held at room temperature. DISCUSSION: The manual handling of VTM production, including filling and sterilization, was optimized. SARS-CoV-2 was spiked into VTM to assess different sterilization methods and measure the effects of storage time and temperature upon VTM performance. While most diagnostic protocols will not require replication competent virus, the use of high quality VTM will allow for the next phase of laboratory analysis in the COVID-19 pandemic, including drug and antibody susceptibility analysis of re-isolated SARS-CoV-2, and for the testing of vaccine escape mutants.


Assuntos
COVID-19/diagnóstico , SARS-CoV-2/crescimento & desenvolvimento , Manejo de Espécimes/métodos , Animais , Antibacterianos/farmacologia , Teste para COVID-19/métodos , Linhagem Celular , Chlorocebus aethiops , Meios de Cultura/química , Humanos , RNA Viral/análise , Células Vero
5.
J Clin Microbiol ; 58(8)2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32341141

RESUMO

The global coronavirus (CoV) disease 2019 (COVID-19) pandemic has resulted in a worldwide shortage of viral transport media and raised questions about specimen stability. The objective of this study was to determine the stability of severe acute respiratory syndrome CoV 2 (SARS-CoV-2) RNA in specimen transport media under various storage conditions. Transport media tested included UTM, UTM-RT, ESwab, M4, and saline (0.9% NaCl). Specimen types tested included nasopharyngeal/oropharyngeal swabs in the above-named transport media, bronchoalveolar lavage (BAL) fluid, and sputum. A high-titer SARS-CoV-2 remnant patient specimen was spiked into pooled SARS-CoV-2 RNA-negative specimen remnants for the various medium types. Aliquots of samples were stored at 18°C to 26°C, 2°C to 8°C, and -10°C to -30°C and then tested at time points up to 14 days. Specimens consistently yielded amplifiable RNA with mean cycle threshold differences of <3 over the various conditions assayed, thus supporting the use and transport of alternative collection media and specimen types under a variety of temperature storage conditions.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico/métodos , Infecções por Coronavirus/diagnóstico , Reagentes de Laboratório/química , Pneumonia Viral/diagnóstico , Manejo de Espécimes/métodos , COVID-19 , Teste para COVID-19 , Humanos , Pandemias , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , SARS-CoV-2 , Temperatura
6.
J Med Virol ; 90(12): 1793-1799, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29995342

RESUMO

PURPOSE: To evaluate the performance of Siriraj liquid-based solution for human papillomavirus (HPV) DNA testing compared with standard transport media. METHODS: This cross-sectional study enrolled 217 women aged 30 years or older who attended for cervical cancer screening or had abnormal cervical cytology, or were diagnosed with cervical cancer at the Department of Obstetrics-Gynecology, Siriraj Hospital from March 2015 to January 2016. We excluded patients with a history of any cervical procedures, hysterectomy, or previous treatment with pelvic irradiation or chemotherapy. Two cervical specimens were collected from each participant. The standard Cervi-Collect Specimen Collection Kit was used to preserve the first sample, and Siriraj liquid-based solution was used for the second one. All samples were sent for HPV DNA testing using the same standard high-risk HPV assay. HPV test results were recorded and statistically analyzed. RESULTS: The results showed agreement between standard transport media and Siriraj liquid-based solution for HPV DNA testing, at a kappa value of 0.935 (P < 0.001). We found no discorrelation for the detection of HPV 16, which accounts for approximately 50% of cervical cancers. The relative sensitivity of Siriraj liquid-based solution and standard transport media in patients with high-grade cervical intraepithelial neoplasia or worse (CIN2+) is 98% (50/51). The relative specificity of Siriraj liquid-based solution and standard transport media in patients with non-CIN2+ is 98.1% (102/104). CONCLUSION: Siriraj liquid-based solution showed almost perfect agreement with the standard transport media for HPV DNA testing. This solution, costing 2 to 3 times less than the commercially available standard media, may be an alternative option for HPV DNA testing.


Assuntos
Meios de Cultura/química , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/diagnóstico , Soluções , Manejo de Espécimes/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Papillomaviridae/classificação , Papillomaviridae/genética , Sensibilidade e Especificidade
7.
Dent Traumatol ; 34(2): 59-70, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29292570

RESUMO

BACKGROUND/AIMS: A wide variety of materials has been researched for their use as potential storage media for avulsed teeth, but it is essential to recognize the medium most recommended for improvement of the prognosis of avulsed teeth. The aim of this systematic review was to identify the most recommended medium to store and transport avulsed teeth based on the survival of periodontal ligament (PDL) cells as determined by in vitro studies. METHODS: Only laboratory-based experimental studies on PDL cells found on adult permanent teeth were included. Data were collected using PubMed, CINAHL plus (EBSCO host), and the Cochrane Library, along with Google Scholar and a hand search. The key terms employed were permutations of [avulsed permanent teeth* OR dental avulsion* OR knocked out teeth*] AND [storage media* OR transport media* OR biological transport* OR PDL cell viability* OR PDL cell survival*]. A customized data extraction pro forma was used to extract the data and to evaluate the quality and risk of bias. RESULTS: The initial search yielded 978 articles, but only 67 were selected. Milk was the most recommended individual medium followed by Hank's balanced salt solution. Among natural products other than milk, propolis and coconut water were most frequently recommended. Recommendations were based on maintenance of PDL cell viability followed by ease of availability, low cost, and long shelf life. CONCLUSIONS: Natural products are more effective in maintaining the PDL cell viability compared to synthetic products. Some storage media recommendations were also based upon practical aspects. Although natural products other than milk have more recommendations as a group, milk is the most recommended storage medium individually, based not only on PDL cell viability, but also practical considerations.


Assuntos
Soluções para Preservação de Órgãos , Ligamento Periodontal/citologia , Avulsão Dentária , Animais , Sobrevivência Celular , Cocos , Humanos , Leite , Própole
9.
J Med Virol ; 87(10): 1796-805, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26243168

RESUMO

The ability of a non-propagating microbial transport medium to maintain the viability of clinically relevant viruses was compared to a similar commercial medium to establish performance equivalence. Two dilutions of stock of test viruses, namely adenovirus (AdV), cytomegalovirus (CMV), echovirus Type 30 (EV), herpes simplex virus (HSV) types 1 and 2, influenza A, parainfluenza 3 (PIV), respiratory syncytial virus (RSV), and varicella zoster virus (VZV), were spiked into Puritan® Medical Products Company Universal Transport System (UniTranz-RT™) and BD(TM) Universal Viral Transport System (UVT) and incubated at 4 °C and room temperature (RT) for up to 72 hr. Post incubation assessment of recovery of AdV, EV, HSV-2, PIV, and VZV from UniTranz-RT™ and UVT using shell vial assays followed by immunofluorescence staining demonstrated statistically significant differences between both transport media. In general, significantly higher recoveries of AdV, EV, and VZV were found from UniTranz-RT™ than UVT whereas HSV-2 and PIV were recovered better from UVT than UniTranz-RT™, under specific test conditions. The recovery of HSV-1, influenza A, PIV, and RSV showed no significant differences between transport media. Sulforhodamine B-based assay analysis of UniTranz-RT™ lots prior to and at expiration exhibited no cytotoxicity. The overall results of the study validate the full performance of UniTranz-RT™ as a viral transport medium and establish its effectiveness on par with the UVT.


Assuntos
Viabilidade Microbiana , Manejo de Espécimes/métodos , Meios de Transporte/métodos , Adenoviridae/crescimento & desenvolvimento , Meios de Cultura , Citomegalovirus/crescimento & desenvolvimento , Herpesvirus Humano 1/crescimento & desenvolvimento , Herpesvirus Humano 2/crescimento & desenvolvimento , Herpesvirus Humano 3/crescimento & desenvolvimento , Humanos , Preservação Biológica/métodos , Vírus Sinciciais Respiratórios/crescimento & desenvolvimento , Meios de Transporte/normas , Vírus/crescimento & desenvolvimento
10.
Front Vet Sci ; 11: 1304022, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38515532

RESUMO

There is a critical need for an inactivation method that completely inactivates pathogens at the time of sample collection while maintaining the nucleic acid quality required for diagnostic PCR testing. This inactivation method is required to alleviate concerns about transmission potential, minimize shipping complications and cost, and enable testing in lower containment laboratories, thereby enhancing disease diagnostics through improved turn-around time. This study evaluated a panel of 10 surrogate viruses that represent highly pathogenic animal diseases. These results showed that a commercial PrimeStore® molecular transport media (PSMTM) completely inactivated all viruses tested by >99.99%, as determined by infectivity and serial passage assays. However, the detection of viral nucleic acid by qRT-PCR was comparable in PSMTM and control-treated conditions. These results were consistent when viruses were evaluated in the presence of biological material such as sera and cloacal swabs to mimic diagnostic sample conditions for non-avian and avian viruses, respectively. The results of this study may be utilized by diagnostic testing laboratories for highly pathogenic agents affecting animal and human populations. These results may be used to revise guidance for select agent diagnostic testing and the shipment of infectious substances.

11.
Front Microbiol ; 15: 1384991, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38800755

RESUMO

Introduction: Rapid identification of infected individuals through viral RNA or antigen detection followed by effective personal isolation is usually the most effective way to prevent the spread of a newly emerging virus. Large-scale detection involves mass specimen collection and transportation. For biosafety reasons, denaturing viral transport medium has been extensively used during the SARS-CoV-2 pandemic. However, the high concentrations of guanidinium isothiocyanate (GITC) in such media have raised issues around sufficient GITC supply and laboratory safety. Moreover, there is a lack of denaturing transport media compatible with SARS-CoV-2 RNA and antigen detection. Methods: Here, we tested whether supplementing media containing low concentrations of GITC with ammonium sulfate (AS) would affect the throat-swab detection of SARS-CoV-2 or a viral inactivation assay targeting coronavirus and other enveloped and non-enveloped viruses. The effect of adding AS to the media on RNA stability and its compatibility with SARS-CoV-2 antigen detection were also tested. Results and discussion: We found that adding AS to the denaturing transport media reduced the need for high levels of GITC, improved SARS-COV-2 RNA detection without compromising virus inactivation, and enabled the denaturing transport media compatible with SARS-CoV-2 antigen detection.

12.
Dermatopathology (Basel) ; 11(1): 52-61, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38390848

RESUMO

Direct immunofluorescence is a vital diagnostic test for assessing vesiculobullous disorders, vasculitides, and connective tissue diseases. It is a robust and valuable technique that offers essential diagnostic information for many critical dermatoses. Dermatopathologists depend heavily on the data obtained from direct immunofluorescence evaluation to confirm final diagnoses. Selecting the most appropriate biopsy site is necessary for maximizing diagnostic accuracy, and the best site may vary depending on the clinical differential diagnosis. Inaccurate biopsy site selection can significantly impact the accuracy of the results. To optimize the use of direct immunofluorescence studies, this review provides helpful guidelines and some practical tips for selecting the best biopsy site.

13.
J Clin Virol ; 159: 105356, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36608619

RESUMO

BACKGROUND: Mpox (formerly monkeypox) is an emerging zoonotic disease of public health concern that presents as a rash mimicking other common viral exanthems. Unlike traditional testing algorithms relying on several assays, the BioFire FilmArray meningitis/encephalitis (ME) panel simultaneously detects common viruses causing rashes; however, Biofire ME is only licensed for testing on cerebral spinal fluid. OBJECTIVES: This study evaluated use of the Biofire ME panel for detection and discrimination of herpes simplex virus types 1 and 2 (HSV-1 and HSV-2), varicella zoster virus (VZV), human herpesviruses type 6 (HHV-6), enteroviruses (EVs), and human paraechoviruses (HPeVs) from a dermal or mucocutaneous swabs collected in universal transport media (UTM). STUDY DESIGN: Results of the BioFire ME panel were compared against methods used during clinical testing. Ten-fold serial dilutions in UTM of cultured viruses were used to compare analytical sensitivity, and analytical specificity was assessed using panels of microorganisms in UTM. Clinical sensitivity and specificity were assessed using 20 positive specimens each for HHV-1, HHV-2, HHV-6, VZV, EVs, and HPeV, as well as 35 known negative specimens that included 15 mpox-positive specimens. RESULTS: Biofire ME was as sensitive as comparator methods, and correctly discriminated all HSV-1, HSV-2, VZV, HHV-6, EVs, and HPeVs from mpox and mpox-mimickers. Cross-reaction between EV and rhinoviruses A, B, and C were noted in the specificity panel. CONCLUSIONS: Swabs in UTM collected for mpox testing are suitable for use on the Biofire ME panel, allowing more streamlined diagnostic testing for viral exanthems in patients under investigation for mpox infection.


Assuntos
Encefalite , Herpesvirus Humano 1 , Herpesvirus Humano 6 , Meningite , Mpox , Viroses , Vírus , Humanos , Encefalite/etiologia , Herpesvirus Humano 2 , Herpesvirus Humano 3 , Viroses/diagnóstico
14.
MethodsX ; 8: 101433, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34226865

RESUMO

Precautionary measures of physical isolation, social distancing, and masks have all aided in controlling the spread of COVID-19. However, detection of the virus is crucial to implement isolation of infected individuals. This paper presents the innovative repurposing of lab materials, workspace, and personnel in response to the COVID-19-induced shutdown and consequential shortage of commercially made virus transport media (VTM). This method for VTM production highlights the ability of standard research labs to fulfill the needs of those affected by the pandemic and potential recurrence of outbreaks. Further, the collaboration of the various entities at The Ohio State University Wexner Medical Center (OSUWMC) allowed for efficient production and distribution of VTM tubes to facilitate mass COVID-19 testing. We propose that implementation of this process by university research labs would enable quicker interventions, potentially better outcomes, and prevention of further spread of disease.

15.
J Med Microbiol ; 70(3)2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33734960

RESUMO

Introduction. The COVID-19 pandemic, which began in 2020 is testing economic resilience and surge capacity of healthcare providers worldwide. At the time of writing, positive detection of the SARS-CoV-2 virus remains the only method for diagnosing COVID-19 infection. Rapid upscaling of national SARS-CoV-2 genome testing presented challenges: (1) Unpredictable supply chains of reagents and kits for virus inactivation, RNA extraction and PCR-detection of viral genomes. (2) Rapid time to result of <24 h is required in order to facilitate timely infection control measures.Hypothesis. Extraction-free sample processing would impact commercially available SARS-CoV-2 genome detection methods.Aim. We evaluated whether alternative commercially available kits provided sensitivity and accuracy of SARS-CoV-2 genome detection comparable to those used by regional National Healthcare Services (NHS).Methodology. We tested several detection methods and tested whether detection was altered by heat inactivation, an approach for rapid one-step viral inactivation and RNA extraction without chemicals or kits.Results. Using purified RNA, we found the CerTest VIASURE kit to be comparable to the Altona RealStar system currently in use, and further showed that both diagnostic kits performed similarly in the BioRad CFX96 and Roche LightCycler 480 II machines. Additionally, both kits were comparable to a third alternative using a combination of Quantabio qScript one-step Quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR) mix and Centre for Disease Control and Prevention (CDC)-accredited N1 and N2 primer/probes when looking specifically at borderline samples. Importantly, when using the kits in an extraction-free protocol, following heat inactivation, we saw differing results, with the combined Quantabio-CDC assay showing superior accuracy and sensitivity. In particular, detection using the CDC N2 probe following the extraction-free protocol was highly correlated to results generated with the same probe following RNA extraction and reported clinically (n=127; R2=0.9259).Conclusion. Our results demonstrate that sample treatment can greatly affect the downstream performance of SARS-CoV-2 diagnostic kits, with varying impact depending on the kit. We also showed that one-step heat-inactivation methods could reduce time from swab receipt to outcome of test result. Combined, these findings present alternatives to the protocols in use and can serve to alleviate any arising supply-chain issues at different points in the workflow, whilst accelerating testing, and reducing cost and environmental impact.


Assuntos
Teste de Ácido Nucleico para COVID-19 , COVID-19/diagnóstico , SARS-CoV-2/isolamento & purificação , Manejo de Espécimes/métodos , Meios de Cultura , Temperatura Alta , Humanos , RNA Viral/genética , RNA Viral/isolamento & purificação , Kit de Reagentes para Diagnóstico , SARS-CoV-2/genética , Sensibilidade e Especificidade , Inativação de Vírus
16.
J Med Microbiol ; 70(10)2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34665113

RESUMO

In recent years, metagenomics and then culturomics, which consists of the multiplication of media and culture conditions and the rapid identification of all bacterial colonies, have generated renewed interest in the human microbiota, and diseases associated with modifications in its composition in particular. The sample transport media included in diverse swab transport systems and the storage conditions are among the factors that influence the results of the culturomics. In this study, we compared the results of culturomics from paired skin, oral and rectal swabs from intensive care unit (ICU) patients using Culture Top sample transport medium as compared to our routine one. From 152 clinical samples, we were able to isolate and identify 45 600 colonies, belonging to 338 different bacterial species. The transport system Culture Top identified 282 different bacterial species, while 244 were identified by our routine system. Of these, 188 different bacterial species were commonly identified using both transport systems, while 94 (27.8 %) and 56 (16.5 %) were only identified using Culture Top and our routine system, respectively (P<0.001), but there was no significant difference in bacterial diversity at the genus or phylum level, or in terms of their type of respiration and cell wall. In conclusion, the Culture Top transport system appears to be complementary to our routine system, although it seems slightly superior in terms of isolated bacterial species.


Assuntos
Bactérias/isolamento & purificação , Meios de Cultura , Microbioma Gastrointestinal , Manejo de Espécimes/métodos , Humanos , Metagenômica/métodos
17.
Artigo em Inglês | MEDLINE | ID: mdl-34444305

RESUMO

The collection and storage of water-related matrices such as biofilm from collection to processing are critical for the detection of Legionella pneumophila by cultural and molecular tests. SRK™ is a liquid medium that acts both as an antimicrobial neutralizing agent and a transport medium for bacterial culture enumeration and is useful to maintain the stability of the sample from collection to analysis. The aims of this study were to evaluate Legionella pneumophila viability and bacterial nucleic acids' stability in SRK™ medium over time at different storage conditions. Artificial bacterial inoculates with an approximate concentration of 104, 103 and 102 CFU/mL were made using Legionella pneumophila certified reference material suspended in SRK™ medium. Bacteria recovery was analyzed by cultural and molecular methods at time 0, 24 and 48 h at room temperature and at 0, 24, 48 and 72 h at 2-8 °C, respectively. SRK™ medium supported Legionella pneumophila culture viability with CFU counts within the expected range. The recovery after 72 h at 2-8 °C was 83-100% and 75-95% after 48 h at room temperature. Real-time PCR appropriately detected Legionella pneumophila DNA at each temperature condition, dilution and time point. Results demonstrated a good performance of SRK™ medium for the reliable recovery of environmental Legionella.


Assuntos
Legionella pneumophila , Legionella , Meios de Cultura , Legionella/genética , Legionella pneumophila/genética , Reação em Cadeia da Polimerase em Tempo Real , Microbiologia da Água
18.
Front Med (Lausanne) ; 8: 661358, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33869258

RESUMO

The high infectivity of SARS-CoV-2 makes it essential to develop a rapid and accurate diagnostic test so that carriers can be isolated at an early stage. Viral RNA in nasopharyngeal samples by RT-PCR is currently considered the reference method although it is not recognized as a strong gold standard due to certain drawbacks. Here we develop a methodology combining the analysis of from human nasopharyngeal (NP) samples by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) with the use of machine learning (ML). A total of 236 NP samples collected in two different viral transport media were analyzed with minimal sample preparation and the subsequent mass spectra data was used to build different ML models with two different techniques. The best model showed high performance in terms of accuracy, sensitivity and specificity, in all cases reaching values higher than 90%. Our results suggest that the analysis of NP samples by MALDI-TOF MS and ML is a simple, safe, fast and economic diagnostic test for COVID-19.

19.
Lab Med ; 52(2): e39-e45, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33225352

RESUMO

OBJECTIVE: With the COVID-19 pandemic, there have been supply challenges necessitating that laboratories must prepare their own viral transport medium (VTM), which provides stability for clinical specimens for diagnostic viral testing. METHODS: Within a veteran affairs medical center clinical laboratory, VTM was prepared with a Hanks Balanced Salt Solution (HBSS) 500 mL bottle with phenol red, sterile heat-inactivated fetal bovine serum (FBS), gentamicin sulfate (50 mg/mL), and amphotericin B (250 µg/mL). An antimicrobial mixture was made of 50 mL each of amphotericin B and gentamicin sulfate. Ten mL of FBS and 2 mL of the antimicrobial mixture were mixed into the HBSS bottle, from which 3 mL aliquots were made. Sterility and efficacy check were assessed. These preparations were conducted at our VAMC's clinical laboratory to assure adequate VTM supply during the COVID-19 shortage. RESULTS: The VTM was successfully prepared in-house, supporting uninterrupted testing for the facility and other affiliated medical facilities/centers and community living centers. CONCLUSION: This quality assurance/improvement report represents the first published manuscript on feasible VTM preparation exclusively within a clinical microbiology laboratory during the COVID-19 pandemic.


Assuntos
COVID-19 , Meios de Cultura , SARS-CoV-2 , Humanos , Controle de Qualidade , Manejo de Espécimes
20.
Iran J Microbiol ; 12(3): 216-222, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32685118

RESUMO

BACKGROUND AND OBJECTIVES: Antimicrobial resistance of Neisseria gonorrhoeae is globally spread and threatening. Culturing of N. gonorrhoeae is the only method to collect live isolates for investigation antimicrobial resistance profile. Therefore, quality assessment of N. gonorrhoeae culture is essential for successful isolation of gonococci. This study was conducted to evaluate deferred and bedside culture of N. gonorrhoeae depending on the year season and temperature condition of transport media temporary storage. MATERIALS AND METHODS: Urogenital swabs from 46 symptomatic heterosexual patients with gonorrhoea and subculture of N. gonorrhoeae in 46 suspensions in concentrations 1.5 × 108 CFU/ml were subjected to the study. Non-nutritive transporting medium Amies Agar Gel Medium with charcoal (Copan Diagnostics Inc., Brescia, Italy) was used for deferred culture and selective Chocolate agar TM+PolyViteX VCAT3 (BioMérieux, Marcy-l'Étoile, France) for both tested methods of culture. RESULTS: The specificity of both bedside and deferred methods of culture was 100%. The sensitivity of deferred culture was higher than of bedside culture (82.6% vs 47.8%, p<0.0005). Deferred culture showed significantly higher sensitivity comparing to bedside culture in summer (100% vs 50%, p=0.003), and comparably the same as for bedside culture in autumn, winter and spring. CONCLUSION: The viability of N. gonorrhoeae subcultures was significantly higher in refrigerated samples from transport media than from ambient one after exposition from 48 to 96 hours. Optimal viability of N. gonorrhoeae was observed when transport swabs were kept refrigerated up to 48 h (73.9-93.5%) or ambiently - up to 24 h (87%). Updating laboratory guidelines regarding sampling and timely specimen processing might improve gonococcal culture performance.

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