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Digital PCR (dPCR) holds immense potential for precisely detecting nucleic acid markers essential for personalized medicine. However, its broader application is hindered by high consumable costs, complex procedures, and restricted multiplexing capabilities. To address these challenges, an all-in-one dPCR system is introduced that eliminates the need for microfabricated chips, offering fully automated operations and enhanced multiplexing capabilities. Using this innovative oscillation-induced droplet generation technique, OsciDrop, this system supports a comprehensive dPCR workflow, including precise liquid handling, pipette-based droplet printing, in situ thermocycling, multicolor fluorescence imaging, and machine learning-driven analysis. The system's reliability is demonstrated by quantifying reference materials and evaluating HER2 copy number variation in breast cancer. Its multiplexing capability is showcased with a quadruplex dPCR assay that detects key EGFR mutations, including 19Del, L858R, and T790M in lung cancer. Moreover, the digital stepwise melting analysis (dSMA) technique is introduced, enabling high-multiplex profiling of seven major EGFR variants spanning 35 subtypes. This innovative dPCR system presents a cost-effective and versatile alternative, overcoming existing limitations and paving the way for transformative advances in precision diagnostics.

Background and Objectives: Brucellosis, a zoonotic bacterial disease caused by Brucella, affects humans and domestic animals, leading to significant economic loss. This study examined suspected cases in North Khorasan, Iran, to understand the prevalence of infection and its characteristics in this region. Materials and Methods: Blood specimens were collected from 200 patients suspected of brucellosis after obtaining informed consent. Serum samples were tested using RBPT, Wright, and 2-ME agglutination tests. Blood samples were cultured on Brucella agar, and positive cultures underwent biotyping and PCR assays. A questionnaire identified correlated risk factors. Results: RBPT, Wright, and 2-ME tests showed 25% brucellosis seroprevalence in symptomatic patients. In contrast, the prevalence was 2.5% among those with positive blood cultures. Notably, all culture-positive patients were also serologically positive, with titers exceeding 1:320 in Wright and 2-ME tests. Most positive cases were in people in their 30s, with B. melitensis biovar 1 identified as the causative agent, and the results were confirmed by multiplex PCR. Significant risk factors include contact with livestock and consumption of raw milk (P < 0.0001). Conclusion: The findings highlighted the importance of comprehensive diagnostic approaches for accurate identification of brucellosis. Furthermore, education regarding close contact with animals and pasteurization of dairy products is essential for controlling human brucellosis. [ABSTRACT FROM AUTHOR]

Objective: Lower respiratory tract infections (LRTI) are among the major causes of mortality in children worldwide. Our study aimed to determine viral agents in children under five years of age who were followed up with acute LRTI. Methods: Nasopharyngeal swab samples were taken from children aged 1 month to 5 years who were diagnosed with LRTI at the Bezmialem Vakıf University pediatric emergency department between March 1, 2015 and January 31, 2016. Cases with underlying chronic diseases were excluded from the study. The presence of the agent was investigated in the samples taken using the real-time polymerase chain reaction method. The distribution of cases in which the agent was detected according to age groups and seasons was examined. The relationship between the agent and the clinical and laboratory findings was investigated. Results: Of the 95 patients included in the study, 51 (53.7%) were male, 44 (46.3%) were female, and the mean age was 26.2 months. The presence of viruses was shown in 50 cases (52.6%). The most frequently detected viruses were rhinovirus (28%), human bocavirus (HBoV) (26%) and respiratory syncytial virus (RSV) (24%). While RSV infections were more common in winter months, HBoV was observed to persist throughout the year. No significant relationship was found between the clinical and laboratory findings of the patients and the agents. Conclusion: Viral etiology was detected in 52.6% of the cases. Molecular tests are valuable in detecting more than one virus in the distribution of viruses among different age groups. [ABSTRACT FROM AUTHOR]

Objective: Lower respiratory tract infections (LRTI) are among the major causes of mortality in children worldwide. Our study aimed to determine viral agents in children under five years of age who were followed up with acute LRTI. Methods: Nasopharyngeal swab samples were taken from children aged 1 month to 5 years who were diagnosed with LRTI at the Bezmialem Vakıf University pediatric emergency department between March 1, 2015 and January 31, 2016. Cases with underlying chronic diseases were excluded from the study. The presence of the agent was investigated in the samples taken using the real-time polymerase chain reaction method. The distribution of cases in which the agent was detected according to age groups and seasons was examined. The relationship between the agent and the clinical and laboratory findings was investigated. Results: Of the 95 patients included in the study, 51 (53.7%) were male, 44 (46.3%) were female, and the mean age was 26.2 months. The presence of viruses was shown in 50 cases (52.6%). The most frequently detected viruses were rhinovirus (28%), human bocavirus (HBoV) (26%) and respiratory syncytial virus (RSV) (24%). While RSV infections were more common in winter months, HBoV was observed to persist throughout the year. No significant relationship was found between the clinical and laboratory findings of the patients and the agents. Conclusion: Viral etiology was detected in 52.6% of the cases. Molecular tests are valuable in detecting more than one virus in the distribution of viruses among different age groups.

BACKGROUND: Multiplex PCR amplifies numerous targets in a single tube reaction and is essential in molecular biology and clinical diagnostics. One of its most important applications is in the targeted sequencing of pathogens. Despite this importance, few tools are available for designing multiplex primers. RESULTS: We developed primerJinn, a tool that designs a set of multiplex primers and allows for the in silico PCR evaluation of primer sets against numerous input genomes. We used primerJinn to create a multiplex PCR for the sequencing of drug resistance-conferring gene regions from Mycobacterium tuberculosis, which were then successfully sequenced. CONCLUSIONS: primerJinn provides a user-friendly, efficient, and accurate method for designing multiplex PCR primers for targeted sequencing and performing in silico PCR. It can be used for various applications in molecular biology and bioinformatics research, including the design of assays for amplifying and sequencing drug-resistance-conferring regions in important pathogens.

Bacterial commensals of the human genitourinary tract, Mycoplasma hominis and Ureaplasma species (parvum and urealyticum) can be sexually transmitted, and may cause nongonococcal urethritis, pelvic inflammatory disease, and infertility. Mycoplasma hominis and Ureaplasma species may also cause severe invasive infections in immunocompromised patients. Current culture-based methods for Mycoplasma/Ureaplasma identification are costly and laborious, with a turnaround time between 1 and 2 weeks. We developed a high-throughput, real-time multiplex PCR assay for the rapid detection of M. hominis and Ureaplasma species in urine, genital swab, body fluid, and tissue. In total, 282 specimens were tested by PCR and compared with historic culture results; a molecular reference method was used to moderate discrepancies. Overall result agreement was 99% for M. hominis (97% positive percentage agreement and 100% negative percentage agreement) and 96% for Ureaplasma species (96% positive percentage agreement and 97% negative percentage agreement). Specimen stability was validated for up to 7 days at room temperature. This multiplex molecular assay was designed for implementation in a high-complexity clinical microbiology laboratory. With this method, >90 samples can be tested in one run, with a turnaround time of 4 to 5 hours from specimen extraction to reporting of results. This PCR test is also more labor effective and cheaper than the conventional culture-based test, thus improving laboratory efficiency and alleviating labor shortages.

Abstract Background The emergence of Streptococcus agalactiae infections in patients with bacteremia is increasing. It is crucial to investigate the epidemiology, molecular characteristics, biofilm status, and virulence analysis of Streptococcus agalactiae in these patients. Methods In this cross-sectional study, 61 S. agalactiae isolated from blood infection were subjected to characterization through antimicrobial susceptibility tests, biofilm formation, multilocus sequence typing (MLST), and PCR analysis for detecting resistance (tet and erm family) and virulence genes (alp2/3, alp4, bca, bac, eps, rib, lmb, cylE, and pilus island genes). Results Overall, 32.7% of the isolates demonstrated an inducible clindamycin resistance phenotype. The results showed that 49.2, 24.6, and 8.2% of confirmed Streptococcus agalactiae strains were classified as strong, intermediate, and weak biofilm-forming strains, respectively. tet(M) (57.1%) was recovered most, followed by tet(M) + tet(L) (14.3%), tet(S) + tet(K) (10.7%), tet(M) + tet(K) (8.9%), tet(M) + tet(K) + tet(O) (5.4%), and tet(S) + tet(L) + tet(O) (3.6%). Three virulence gene profiles of cylE, lmb, bca, rib (24.6%; 15/61), cylE, lmb, rib, alp3 (19.7%; 12/61), and cylE, lmb, bac, rib (16.4%; 10/61) were detected in approximately two-thirds of the isolates. MLST revealed that the 61 isolates belonged to six clonal complexes, including CC1 (49.2%), followed by CC12 (18%), CC19 (13.1%), CC22 (9.8%), CC17 (6.6%), and CC283 (3.3%), and 11 different sequence types (STs), including ST1 (24.6%), ST7 (14.8%), ST918 (13.1%), ST2118 (9.8%), ST19 (9.8%), ST48 (6.6%), ST1372 (4.9%), ST22 (4.9%), ST40 (4.9%), ST734 (3.3%), and ST283 (3.3%). Remarkably, all CC1 and CC12 isolates, three-fourths of CC19, and half of CC22 were confirmed as biofilm producers. Conversely, CC17 and CC28 isolates were found to be nonproducers. The occurrence of strong biofilm formation was limited to specific CCs, namely CC1 (34.4%), CC12 (8.2%), CC19 (3.3%), and CC22 (3.3%). Conclusion The high prevalence of CC1 and CC12 clones among S. agalactiae strains reflects the emergence of these lineages as successful clones in Iran, which is a serious concern and poses a potential threat to patients.

Abstract Background The burden and characteristics of respiratory viral infections in children hospitalized for acute respiratory tract infections (ARTIs) during the post-COVID-19 pandemic era are unclear. We analyzed the epidemiological and clinical characteristics of pediatric patients hospitalized with common respiratory virus infections before and after relaxation of non-pharmaceutical interventions in Hangzhou, China and evaluated the diagnostic value of the six-panel respiratory pathogen detection system. Methods Six types of respiratory viruses were detected in respiratory samples from children with suspected ARTIs by multiplex real-time quantitative polymerase chain reaction (RT-qPCR). Changes in virus detection rates and epidemiological and clinical characteristics, obtained from electronic health records, were analyzed. Binary logistic regression was used to identify respiratory tract infections risk factors. Multiplex RT-qPCR and targeted next-generation sequencing results were compared in random samples. Results Among the 11,056 pediatric samples, 3228 tested positive for one or more of six common respiratory pathogens. RSV and PIV-3 detection rates differed significantly across age groups (both P

Mantidis Ootheca (sangpiaoxiao), the egg case of the mantis, is a type of insect-derived traditional medicine widely used in East Asia. However, species identification based on egg morphology is challenging, leading to the distribution of counterfeit and adulterated products. The use of inauthentic ingredients can pose serious health risks to consumers. This study aimed to develop PCR markers that can rapidly and accurately differentiate between authentic and counterfeit Mantidis Ootheca. The mitochondrial cytochrome c oxidase I (COI) region was sequenced in thirteen samples from four mantis species: Tenodera angustipennis, Statilia maculata, Hierodula patellifera, and T. sinensis. Four sets of SCAR primers were designed based on species-specific nucleotide polymorphisms, and a multiplex SCAR assay was developed by combining all sets of the primers. The sequence-characterized amplified region (SCAR) primers successfully produced amplicons for each target species, even with low-DNA templates or templates containing DNA from multiple samples. No amplification was observed for nontarget species. This study presents a novel approach for identifying authentic Mantidis Ootheca species using DNA-based diagnostic marker assays, which enable rapid and precise species identification. The SCAR assays developed in this study will aid in maintaining quality control and promoting the standardization of commercial Mantidis Ootheca products. [ABSTRACT FROM AUTHOR]

With approximately half a billion events per year, lower respiratory tract infections (LRTIs) represent a major challenge for the global public health. Among LRTI cases, those caused by Gram-negative bacteria (GNB) are associated with a poorer prognostic. Standard-of-care etiologic diagnostics is lengthy and difficult to establish, with more than half of cases remaining microbiologically undocumented. Recently, syndromic molecular diagnostic panels became available, enabling simultaneous detection of tens of pathogen-related and antimicrobial-resistance genetic markers within a few hours. In this narrative review, we summarize the available data on the performance of molecular diagnostics in GNB pneumonia, highlighting the main strengths and limitations of these assays, as well as the main factors influencing their clinical utility. We searched MEDLINE and Web of Science databases for relevant English-language articles. Molecular assays have higher analytical sensitivity than cultural methods, and show good agreement with standard-of-care diagnostics regarding detection of respiratory pathogens, including GNB, and identification of frequent patterns of resistance to antibiotics. Clinical trials reported encouraging results on the usefulness of molecular assays in antibiotic stewardship. By providing early information on the presence of pathogens and their probable resistance phenotypes, these assays assist in the choice of targeted therapy, in shortening the time from sample collection to appropriate antimicrobial treatment, and in reducing unnecessary antibiotic use. [ABSTRACT FROM AUTHOR]

Prolonged positive polymerase chain reaction (PCR) results, irrespective of the transmission risk, can lead to prolonged restrictions on daily activities and infection precaution interventions. Studies evaluating the duration of PCR positivity for multiple pathogens in a single patient cohort are scarce. This study aimed to evaluate and compare the durations of PCR positivity for multiple respiratory viruses among children and adolescents. This retrospective study was conducted between April 2018 and March 2024 using a multiplex PCR respiratory panel for symptomatic children and adolescents who had at least two tests within 90 days of study period, with the first PCR test positive. The rate and likelihood of persistent PCR positivity were evaluated for multiple respiratory viruses. For 1325 positive results, repeat tests were conducted within 90 days. The persistent PCR positivity rate at repeat testing decreased over time (60.6%, Days 1–15 and 21.7%, Days 76–90, after the first test). In multivariate logistic regression analysis, an increased likelihood of persistent PCR positivity was observed for rhinovirus/enterovirus and adenovirus, whereas decreased likelihood of persistent positivity was seen in influenza and seasonal coronaviruses, compared with parainfluenza viruses. Persistent PCR positivity is common for multiple respiratory viruses in symptomatic children. [ABSTRACT FROM AUTHOR]

Background: The burden and characteristics of respiratory viral infections in children hospitalized for acute respiratory tract infections (ARTIs) during the post-COVID-19 pandemic era are unclear. We analyzed the epidemiological and clinical characteristics of pediatric patients hospitalized with common respiratory virus infections before and after relaxation of non-pharmaceutical interventions in Hangzhou, China and evaluated the diagnostic value of the six-panel respiratory pathogen detection system. Methods: Six types of respiratory viruses were detected in respiratory samples from children with suspected ARTIs by multiplex real-time quantitative polymerase chain reaction (RT-qPCR). Changes in virus detection rates and epidemiological and clinical characteristics, obtained from electronic health records, were analyzed. Binary logistic regression was used to identify respiratory tract infections risk factors. Multiplex RT-qPCR and targeted next-generation sequencing results were compared in random samples. Results: Among the 11,056 pediatric samples, 3228 tested positive for one or more of six common respiratory pathogens. RSV and PIV-3 detection rates differed significantly across age groups (both P < 0.001), and were more common in younger children. PIV-1 was more common in infants, toddlers, and preschoolers than in school-age children (P < 0.001). FluB was predominantly detected in school-age children (P < 0.001). RSV-, ADV-, and PIV-1-positivity rates were higher in 2022 than in 2023. Seasonal viral patterns differed across years. RSV (OR 9.156. 95% CI 5.905–14.195) and PIV-3 (OR 1.683, 95% CI 1.133–2.501) were risk factors for lower respiratory tract infections. RSV-positivity was associated with severe pneumonia (P = 0.044). PIV-3 (OR 0.391, 95% CI 0.170–0.899), summer season (OR 1.982, 95% CI 1.117–3.519), and younger age (OR 0.938, 95% CI 0.893–0.986) influenced pneumonia severity. Multiplex RT-qPCR showed good diagnostic performance. Conclusion: After changes in COVID-19 prevention and control strategies, six common respiratory viruses in children were prevalent in 2022–2023, with different seasonal epidemic characteristics and age proclivities. RSV and PIV-3 cause lower, and FluA, FluB, and ADV more typically cause upper respiratory tract infections. Infancy and summer season influence severe pneumonia risk. Multiplex RT-qPCR is valuable for accurate and timely detection of respiratory viruses in children, which facilitates management, treatment, and prevention of ARTIs. [ABSTRACT FROM AUTHOR]

Background and Objectives: Brucellosis, a zoonotic bacterial disease caused by Brucella, affects humans and domestic animals, leading to significant economic loss. This study examined suspected cases in North Khorasan, Iran, to understand the prevalence of infection and its characteristics in this region. Materials and Methods: Blood specimens were collected from 200 patients suspected of brucellosis after obtaining informed consent. Serum samples were tested using RBPT, Wright, and 2-ME agglutination tests. Blood samples were cultured on Brucella agar, and positive cultures underwent biotyping and PCR assays. A questionnaire identified correlated risk factors. Results: RBPT, Wright, and 2-ME tests showed 25% brucellosis seroprevalence in symptomatic patients. In contrast, the prevalence was 2.5% among those with positive blood cultures. Notably, all culture-positive patients were also serologically positive, with titers exceeding 1:320 in Wright and 2-ME tests. Most positive cases were in people in their 30s, with B. melitensis biovar 1 identified as the causative agent, and the results were confirmed by multiplex PCR. Significant risk factors include contact with livestock and consumption of raw milk (P < 0.0001). Conclusion: The findings highlighted the importance of comprehensive diagnostic approaches for accurate identification of brucellosis. Furthermore, education regarding close contact with animals and pasteurization of dairy products is essential for controlling human brucellosis.

The aim of this review is to provide practical guidance for the molecular diagnosis of parasitic diseases in Korea in 2024. Specifically, the prevalence of parasitic diseases, commercially available molecular diagnostic kits, and reference laboratories for molecular diagnosis are presented. It is based on the literature and the medical diagnosis device database of the Korea Disease Control and Prevention Agency. In Korea, molecular diagnostic kits are available for intestinal protozoa (Giardia lamblia, Entamoeba histolytica, Cryptosporidium hominis, and Cryptosporidium parvum), Trichomonas vaginalis, and malarial parasites. Molecular diagnosis of other parasites is also possible; however, there is no commercially available kit. Therefore, parasite samples or derivatives for molecular diagnosis should be sent to specific laboratories, the parasitology departments of medical schools, or the Division of Vectors and Parasitic Diseases, Bureau of Infectious Disease Diagnosis Control at the Korea Disease Control and Prevention Agency. In commercial diagnostic kits, multiplex real-time polymerase chain reaction (PCR) is used to rapidly and easily detect the amplified parasitic DNA. The loop-mediated isothermal amplification (LAMP) was developed to diagnose T. vaginalis and Acanthamoeba infections. Its merits are that it does not require a PCR machine and has a short test time of approximately 60 min. Although LAMP is not commercially available, it may be widely used to screen for parasitic diseases. Commercial molecular diagnostic kits for parasitic diseases are limited to the clinical setting in Korea. Available kits are used to diagnose certain intestinal protozoa, T. vaginalis, and to differentiate Plasmodium species using multiplex PCR.

Background: The optimal timing for applying the BioFire FilmArray Pneumonia Panel (FAPP) in intensive care unit (ICU) patients with hospital-acquired pneumonia (HAP) or ventilator-associated pneumonia (VAP) remains undefined, and there are limited data on its impact on antimicrobial stewardship. Methods: This retrospective study was conducted at a referral hospital in Taiwan from November 2019 to October 2022. Adult ICU patients with HAP/VAP who underwent FAPP testing were enrolled. Patient data, FAPP results, conventional microbiological testing results, and the real-world impact of FAPP results on antimicrobial therapy adjustments were assessed. Logistic regression was used to determine the predictive factors for bacterial detection by FAPP. Results: Among 592 respiratory specimens, including 564 (95.3%) endotracheal aspirate specimens, 19 (3.2%) expectorated sputum specimens and 9 (1.5%) bronchoalveolar lavage specimens, from 467 patients with HAP/VAP, FAPP testing yielded 368 (62.2%) positive results. Independent predictors for positive bacterial detection by FAPP included prolonged hospital stay (odds ratio [OR], 3.14), recent admissions (OR, 1.59), elevated C-reactive protein levels (OR, 1.85), Acute Physiology and Chronic Health Evaluation II scores (OR, 1.58), and septic shock (OR, 1.79). Approximately 50% of antimicrobial therapy for infections caused by Gram-negative bacteria and 58.4% for Gram-positive bacteria were adjusted or confirmed after obtaining FAPP results. Conclusions: This study identified several factors predicting bacterial detection by FAPP in critically ill patients with HAP/VAP. More than 50% real-world clinical practices were adjusted or confirmed based on the FAPP results. Clinical algorithms for the use of FAPP and antimicrobial stewardship guidelines may further enhance its benefits.

Tung Nguyen Thanh,1 Sang Trieu Tien,2 Phong Nguyen Van,2 Son Dang Thai,3 Thuc Luong Cong,4 Tuan Dinh Le,5 Son Tien Nguyen,5 Tuan Tran Van,1 Hoang Huy Duong,6 Tien Minh Bui,7 Kien Trung Nguyen7 1Military Institute of Clinical Embryology and Histology, Vietnam Military Medical University, Hanoi, 100000, Vietnam; 2Department of Biology and Medical Genetics, Vietnam Military Medical University, Hanoi, 100000, Vietnam; 3Institute of Biological and Food Technology, Hanoi Open University, Hanoi, 100000, Vietnam; 4Cardiovascular Center, Military Hospital 103, Vietnam Military Medical University, Hanoi, 100000, Vietnam; 5Department of Rheumatology and Endocrinology, Military Hospital 103, Vietnam Military Medical University, Hanoi, 100000, Vietnam; 6Department of Neurology, Thai Binh University of Medicine and Pharmacy, Thai Binh, 410000, Vietnam; 7Department of Obstetrics and Gynecology, Thai Binh University of Medicine and Pharmacy, Thai Binh, 410000, VietnamCorrespondence: Sang Trieu Tien, Department of Biology and Medical Genetics, Vietnam Military Medical University, Hanoi, 100000, Vietnam, Email trieusangk83@yahoo.com.vnBackground: To optimize the multiplex polymerase chain reaction (M-PCR) technique to diagnose microdeletions of azoospermia factors (AZF) on the Y chromosome and initially apply the technique to diagnose male patients with sperm density less than 5× 106 million sperm/mL was assigned to do a test to check for AZF microdeletions on the Y chromosome.Methods: Based on the positive control samples which belong to male subjects who have had 2 healthy children without any assisted reproductive technologies, the M-PCR method was developed to detect simultaneously and accurately AZF microdeletions on 32 male patients with sperm densities below 5× 106 million sperm/mL of semen at the Department of Biology and Medical Genetics – Vietnam Military Medical University.Results: Successful optimization of the M-PCR technique including 7 reactions arranged according to each AZFabc region using 24 STS/gene on the Y chromosome. Initial application to diagnose AZF deletion on 32 azoospermic and oligospermic men reveals that AZFa deletion accounts for 6.25% (2/32); deletion of all 3 regions AZFa,b,c with 18.75% (6/32 cases); The combined deletion rate of AZFb,c is highest, accounting for 56.24% (18/32 patients).Conclusion: Successfully optimized the M-PCR technique in identifying AZF microdeletions using 24 sequence tagged sites (STS)/gene for azoospermic and oligozoospermic men. The M-PCR technique has great potential in the application of AZF deletion diagnosis.Keywords: male infertility, azoospermia factors, AZF, multiplex polymerase chain reaction, M-PCR, sequence tagged sites, STS

Background and Objectives: During the coronavirus pandemic, the overuse of antibiotics to reduce coinfections and mortality may be contributing to the rise of antimicrobial resistance. In this study, we aim to investigate the antibiotic resistance changes of Acinetobacter baumannii post-COVID-19 pandemic in Northern Iran. Materials and Methods: The current study is a cross-sectional study. Between 2022 and 2023, 2190 clinical samples were collected from patients with healthcare-associated infections (HAIs) at four hospitals in Sari, which served as corona centers after the COVID-19 pandemic. Antimicrobial sensitivity was determined using standard broth macro-dilution, and resistance genes were detected using multiplex PCR. Results: Based on the results co-amoxiclav had a resistance rate of 100%, while piperacillin/tazobactam showed the least resistance rate of 29.82%. In terms of GM MIC values, colistin was the most potent against multi-drug resistant isolates. The frequency of bla OXA-51, ampC, aphA6, and bla NDM genes were 100%, 99.12%, 90.35%, and 69.30% respectively. Conclusion: Our study revealed high multi-drug resistance rates. Piperacillin/tazobactam recommended for treating multidrug resistant Acinetobacter baumannii infections in Northern Iran. [ABSTRACT FROM AUTHOR]

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Background: To optimize the multiplex polymerase chain reaction (M-PCR) technique to diagnose microdeletions of azoospermia factors (AZF) on the Y chromosome and initially apply the technique to diagnose male patients with sperm density less than 5× 106 million sperm/mL was assigned to do a test to check for AZF microdeletions on the Y chromosome. Methods: Based on the positive control samples which belong to male subjects who have had 2 healthy children without any assisted reproductive technologies, the M-PCR method was developed to detect simultaneously and accurately AZF microdeletions on 32 male patients with sperm densities below 5× 106 million sperm/mL of semen at the Department of Biology and Medical Genetics – Vietnam Military Medical University. Results: Successful optimization of the M-PCR technique including 7 reactions arranged according to each AZFabc region using 24 STS/gene on the Y chromosome. Initial application to diagnose AZF deletion on 32 azoospermic and oligospermic men reveals that AZFa deletion accounts for 6.25% (2/32); deletion of all 3 regions AZFa,b,c with 18.75% (6/32 cases); The combined deletion rate of AZFb,c is highest, accounting for 56.24% (18/32 patients). Conclusion: Successfully optimized the M-PCR technique in identifying AZF microdeletions using 24 sequence tagged sites (STS)/gene for azoospermic and oligozoospermic men. The M-PCR technique has great potential in the application of AZF deletion diagnosis. [ABSTRACT FROM AUTHOR]

ABSTRACT Seasonal increase of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza virus A/B (Flu A/B), and respiratory syncytial virus (RSV) require rapid diagnostic test methods for the management of respiratory tract infections. In this study, we compared the diagnostic accuracy of Savanna RVP4 (RVP4, QuidelOrtho) with Xpert Xpress Plus SARS-CoV-2/Flu/RSV (Xpert, Cepheid). Nasopharyngeal swabs from patients treated at a tertiary care hospital (Germany) were tested for SARS-CoV-2, Flu A/B, and RSV by RVP4 to assess diagnostic accuracy (reference standard: Xpert). The intra and inter assay precision of Ct-values was assessed by repeated test in triplicates (on day 1) and duplicates (days 2–3). All patients with a physician’s order for a multiplex test for SARS-CoV-2, Flu, and RSV test were included. Duplicate swabs from the same patient, samples with a total volume ≤1 mL, or inappropriate shipment/storage were excluded. In total, 229 swabs were included between September 2023 and February 2024. The concordance between both tests was 96.5% (SARS-CoV-2), 98.7% (Flu A), and 99.6% (RSV). Flu B was not detected by both tests. The RVP4 test had a sensitivity of 85%–95% and a specificity of 100% for the detection of SARS-CoV-2, Flu A, and RSV. The intra and inter assay precision of Ct-values from RVP4 was 3% and 2% (SARS-CoV-2), 5% and 4% (Flu A), and 0% and 3% (RSV), respectively. The Savanna RVP4 has a favorable diagnostic accuracy for the detection of SARS-CoV-2, Flu A, and RSV.IMPORTANCEWe assessed the diagnostic accuracy of a new point-of-care test for the rapid detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza virus A/B (Flu A/B), and respiratory syncytial virus (RSV). The new test has a concordance with the reference standard of 96.5% (SARS-CoV-2), 98.7% (Flu A), and 99.1% (RSV). The sensitivity of 85%–95% and specificity of 100% for the detection of SARS-CoV-2, Flu A, and RSV is comparable with similar nucleic acid amplification-based point of care tests but at lower costs.

Background: Amid the COVID-19 pandemic, the surge in hospital admissions and widespread use of broad-spectrum antibiotics have heightened the risk of hospital-acquired infections from multidrug-resistant (MDR) organisms, particularly Escherichia coli. It is imperative to implement stringent measures to curb the spread of antimicrobial resistance in hospitals and devise robust treatment strategies for patients grappling with such infections. To confront this challenge, a comprehensive study was undertaken to examine MDR extended-spectrum beta-lactamase (MDR-ESBL)-producing Escherichia coli isolates from patients with nosocomial infections following the COVID-19 pandemic in Northern Iran. Materials and Methods: The current study was conducted as a cross-sectional study. A total of 12,834 samples were collected from patients with healthcare-associated infections at four designated corona centers in Northern Iran, following the COVID-19 pandemic. Antimicrobial resistance was determined using standard broth micro-dilution, while resistance genes were accurately detected using the multiplex PCR method. Results: The results indicated that meropenem and ciprofloxacin had a resistance rate of 100% and 98.2%, respectively, while piperacillin-tazobactam showed the highest sensitivity rate at 54.4%. The frequency of specific genes, including blaIMP, blaTEM, AcrA, AcrB, blaCTX, blaOXA-58, aaclb, blaSHV, and aacla, were found to be 100%, 100%, 99.1%, 99.1%, 91.2%, 80.7%, 64.9%, 44.7%, and 37.7%, respectively. Conclusions: In the current study, over 50% of MDR-ESBL-producing Escherichia coli isolates exhibited resistance to antibiotics. A combination of antibiotics, including piperacillin-tazobactam and colistin, is recommended for treating extensively drug-resistant Escherichia coli infections.

Background Multiplex molecular diagnostic panels have greatly enhanced detection of gastrointestinal pathogens. However, data on the impact of these tests on clinical and patient-centered outcomes are limited. Methods We conducted a prospective, multicenter, stepped-wedge trial to determine the impact of multiplex molecular testing at 5 academic children's hospitals on children presenting to the emergency department with acute gastroenteritis. Caregivers were interviewed on enrollment and 7–10 days after enrollment to determine symptoms, risk factors, subsequent medical visits, and impact on family members. During the pre-intervention period, diagnostic testing was performed at the clinician's discretion. During the intervention period, multiplex molecular testing was performed on all children, with results available to clinicians. The primary outcome was return visits to a healthcare provider within 10 days of enrollment. Results Potential pathogens were identified by clinician-ordered tests in 19 of 571 (3.3%) in the pre-intervention period compared with 434 of 586 (74%) in the intervention period; clinically relevant pathogens were detected in 2.1% and 15%, respectively. In the multivariate model, the intervention was associated with a 21% reduction in the odds of any return visit (odds ratio, 0.79; 95% confidence interval,.70–.90) after adjusting for potential confounders. Appropriate treatment was prescribed in 11.3% compared with 19.6% during the intervention period (P =.22). Conclusions Routine molecular multiplex testing for all children who presented to the ED with acute gastroenteritis detected more clinically relevant pathogens and led to a 21% decrease in return visits. Additional research is needed to define patients most likely to benefit from testing. Clinical Trials Registration. NCT02248285. [ABSTRACT FROM AUTHOR]

Purpose: Diarrhea is one of the leading causes of mortality in children living in developing countries. The etiology of acute diarrhea in each healthcare center varies depending on place, time, and population. This study aimed to identify pathogen patterns in human immunodeficiency virus (HIV)-infected and non-HIV children suffering from acute diarrhea, using multiplex real time reverse transcriptase polymerase chain reaction (RT-PCR), in an Indonesian tertiary hospital. Methods: This cross-sectional study was conducted at Dr. Cipto Mangunkusumo National Hospital from March 2019 to April 2020. Results: The study showed that multiplex RT-PCR results were positive in 58.9% of the specimens, with more positive results in HIV-infected children than in non-HIV-infected children (70% vs. 54.7%). Altogether 72 enteropathogens were detected from all specimens. Enteropathogens in non-HIV children with acute diarrhea consisted of bacteria (70.6%) and viruses (29.4%) with a predominance of enteroaggregative Escherichia coli (25.4%), followed by Campylobacter spp. (11.8%), enteropathogenic E. coli (9.8%), Norovirus GII (7.8%), and Clostridium difficile (7.8%). Enteropathogens in HIV-infected children consisted of viruses (57.1%), bacteria (28.6%), and parasites (14.3%) comprising Norovirus GII (24%), Cryptosporidium spp. (14.3%), Campylobacter spp. (14.3%), Norovirus GI (14.3%), and Astrovirus (14.3%). Cryptosporidium spp. was the only parasite found in this study and was found only in HIV-infected children. In non-HIV children with acute diarrhea, most pathogens were invasive bacteria, while in HIV-infected children, more viral and parasite infections occurred, primarily caused by opportunistic pathogens. Conclusion: The pattern of enteropathogens can help clinicians determine further examinations and appropriate empirical antimicrobial therapy for the patient. [ABSTRACT FROM AUTHOR]

Various harmful microalgae coexist in the marine environment, seriously affecting the survival of aquatic animals, the sustainable development of fisheries, and pose a great threat to the safety of aquatic food. Consequently, monitoring these harmful microalgae in the marine aquaculture environment is an urgent issue that needs to be addressed. This paper focused on developing a multiplex polymerase chain reaction (MPCR) assay for the simultaneous detection of representative harmful microalgae commonly distributed in the aquaculture environment along the Chinese coast, including Karenia mikimotoi, Alexandrium tamarense, Chattonella marina, Prorocentrum minimum and Heterosigma akashiwo. First, the internal transcribed spacer and large subunit rDNA of target algal species were selected as target for the design of MPCR primers, the specificity of which was subsequently verified. Next, the MPCR system was established and the reaction conditions were optimized, including primer concentration, dNTP concentration, Mg2+ concentration, the concentration of Taq DNA polymerase, and annealing temperature. Specificity test showed that the established MPCR did not cross-react with all of the control algal species and thus can be used for specific detection of target algal species. The sensitivity test showed that the established MPCR could still detect all of the target algae when the concentration of genomic DNA was as low as 1 ng µL–1. Moreover, the MPCR could still detect K. mikimotoi when the concentration of genomic DNA was as low as 1 pg µL–1. The stability test indicated that the performance of the developed MPCR was not affected by the interfering algal species. In addition, the practicality of the established MPCR assay was evaluated using spiked water samples. The tests with the spiked samples indicated that the detection limit of MPCR for the all of the target algal species was approximately 4 cells mL−1, which can meet the requirement for the warning of HABs caused by them. In conclusion, the MPCR assay established here is characterized with strong specificity and good stability and is expected to be promising for daily monitoring of harmful microalgae in the aquaculture environment as an important alternative to traditional morphology-based methods. [ABSTRACT FROM AUTHOR]

Antibiotics are frequently prescribed to children with pneumonia, although viruses are responsible for most cases. We aimed to evaluate the impact of multiplex polymerase chain reaction (mPCR) on antibiotic use. We conducted a prospective study of children under 14 years of age admitted for suspected viral pneumonia, from October 2019 to June 2022 (except March–November 2020). A mPCR respiratory panel (FilmArray® 2plus, bioMérieux, Marcy-l'Étoile, France) was performed within 72 h of admission. Patients with positive reverse transcription PCR for respiratory syncytial virus, influenza, or SARS-CoV-2 were excluded. We compared the patients with historical controls (2017–2018) who had suspected viral pneumonia but did not undergo an aetiological study. We included 64 patients and 50 controls, with a median age of 26 months. The respiratory panel detected viral pathogens in 55 patients (88%), including 17 (31%) with co-infections. Rhinovirus/enterovirus (n = 26) and human metapneumovirus (n = 22) were the most common pathogens, followed by adenovirus and parainfluenza (n = 10). There were no statistically significant differences in the total antibiotic consumption (83% of cases and 86% of controls) or antibiotics given for ≥72 h (58% vs. 66%). Antibiotics were prescribed in 41% of the cases and 72% of the controls at discharge (p = 0.001). Ampicillin was the most commonly prescribed antibiotic among the patients (44% vs. 18% for controls, p = 0.004), while azithromycin was the most commonly prescribed among the controls (19% vs. 48% for patients and controls, respectively; p = 0.001). Our findings underscore the need for additional interventions alongside molecular diagnosis to reduce antibiotic usage in paediatric community-acquired pneumonia. [ABSTRACT FROM AUTHOR]

The objective of this study was to correlate recurrent vulvovaginitis and Sexually Transmitted Infections (STIs) and analyze the importance of adding the Polymerase Chain Reaction (PCR) test for STIs to the diagnostic work-up of recurrent vulvovaginitis. The descriptive, cross-sectional, observational and retrospective research method was adopted. The medical records of 115 patients treated at a gynecological office were evaluated, who had positive PCR tests for STIs with some microorganism from August 2021 to October 2023. A large number of these patients, corresponding to 26%, had repeated discharges and at least 50% of them were proven to be cured of these discharges after STI treatment. It appears that there may be a relationship between recur-rent vulvovaginitis and STIs, however, it is important to expand this research topic, as the study has limitations. [ABSTRACT FROM AUTHOR]

Background and Objectives: During the coronavirus pandemic, the overuse of antibiotics to reduce coinfections and mortality may be contributing to the rise of antimicrobial resistance. In this study, we aim to investigate the antibiotic resistance changes of Acinetobacter baumannii post-COVID-19 pandemic in Northern Iran. Materials and Methods: The current study is a cross-sectional study. Between 2022 and 2023, 2190 clinical samples were collected from patients with healthcare-associated infections (HAIs) at four hospitals in Sari, which served as corona centers after the COVID-19 pandemic. Antimicrobial sensitivity was determined using standard broth macro-dilution, and resistance genes were detected using multiplex PCR. Results: Based on the results co-amoxiclav had a resistance rate of 100%, while piperacillin/tazobactam showed the least resistance rate of 29.82%. In terms of GM MIC values, colistin was the most potent against multi-drug resistant isolates. The frequency of blaOXA-51, ampC, aphA6, and blaNDM genes were 100%, 99.12%, 90.35%, and 69.30% respectively. Conclusion: Our study revealed high multi-drug resistance rates. Piperacillin/tazobactam recommended for treating multidrug resistant Acinetobacter baumannii infections in Northern Iran.

Dakun Wang,1 Emery Haley,2 Natalie Luke,2 Mohit Mathur,3 Richard A Festa,3 Xinhua Zhao,4 Lori A Anderson,5 Jennifer L Allison,6 Kristen L Stebbins,6 Manuel Jose Diaz,6 David Baunoch7 1Department of Writing, Stat4Ward, Pittsburgh, PA, USA; 2Department of Clinical Research, Pathnostics, Irvine, CA, USA; 3Department of Medical Affairs, Pathnostics, Irvine, CA, USA; 4Department of Statistical Analysis, Stat4Ward, Pittsburgh, PA, USA; 5L. Anderson Diagnostic Market Access Consulting, San Diego, CA, USA; 6DispatchHealth, Denver, CO, USA; 7Pathnostics, Irvine, CA, 92618, USACorrespondence: David Baunoch, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA, 92618, USA, Tel +1 714-966-1221, Fax +1 714-966-1231, Email dbaunoch@pathnostics.comIntroduction: This study compared microbial compositions of midstream and catheter urine specimens from patients with suspected complicated urinary tract infections to determine if emerging and fastidious uropathogens are infecting the bladder or are contaminants.Methods: Urine was collected by in-and-out catheter (n = 1000) or midstream voiding (n = 1000) from 2000 adult patients (≥ 60 years of age) at 17 DispatchHealth sites across 11 states. The two groups were matched by age (mean 81 years), sex (62.1% female, 37.9% male), and ICD-10-CM codes. Microbial detection was performed with multiplex polymerase chain reaction (M-PCR) with a threshold for “positive detection” ≥ 10,000 cells/mL for bacteria or any detection for yeast. Results were divided by sex.Results: In females, 28 of 30 microorganisms/groups were found by both collection methods, while in males 26 of 30 were found by both. There were significant overlaps in the detection and densities of classical uropathogens including Escherichia coli, Enterococcus faecalis, and Klebsiella pneumoniae, as well as emerging uropathogens including Actinotignum schaalii and Aerococcus urinae. In females, detection rates were slightly higher in midstream voided compared to catheter-collected (p = 0.0005) urine samples, while males showed the opposite trend (p < 0.0001). More polymicrobial infections were detected in midstream voided compared to catheter-collected samples (64.4% vs 45.7%, p < 0.0001) in females but the opposite in males (35.6% vs 47.0%, p = 0.002).Discussion: In-and-out catheter-collected and midstream voided urine specimens shared significant similarities in microbial detections by M-PCR, with some differences found for a small subset of organisms and between sexes.Conclusion: Non-invasive midstream voided collection of urine specimens for microbial detection and identification in cases of presumed UTI does not result in significantly more contamination compared to in-and-out catheter-collected specimens. Additionally, organisms long regarded as contaminants should be reconsidered as potential uropathogens.Keywords: urinary tract infection, standard urine culture, diagnostic testing, multiplex polymerase chain reaction, catheter, midstream voided

Background: Multiplex polymerase chain reaction (M-PCR) has increased sensitivity for microbial detection compared with standard urine culture (SUC) in cases diagnosed as urinary tract infections (UTIs), leading to questions whether detected microbes are likely causative of UTIs or are incidental findings. Objective: To compare infection-associated biomarker levels against M-PCR and SUC results in symptomatic cases with a presumptive diagnosis of a UTI by a urologist. Design, setting, and participants: Participants were ≥60 yr old and presented to urology clinics between January and April 2023 with symptoms of UTIs (n = 583). Urine microbial detection was by M-PCR and SUC. Three infection-associated biomarkers (neutrophil gelatinase-associated lipocalin, interleukin-8, and interleukin-1β) were measured by enzyme-linked immunosorbent assay. Symptomatic cases with elevated biomarkers, detection of uropathogens, and a specialist clinical diagnosis of a UTI were considered definitive UTI cases. Outcome measurements and statistical analysis: Distributions were compared using two-sample Wilcoxon rank sum test, with two-tailed p values of

With approximately half a billion events per year, lower respiratory tract infections (LRTIs) represent a major challenge for the global public health. Among LRTI cases, those caused by Gram-negative bacteria (GNB) are associated with a poorer prognostic. Standard-of-care etiologic diagnostics is lengthy and difficult to establish, with more than half of cases remaining microbiologically undocumented. Recently, syndromic molecular diagnostic panels became available, enabling simultaneous detection of tens of pathogen-related and antimicrobial-resistance genetic markers within a few hours. In this narrative review, we summarize the available data on the performance of molecular diagnostics in GNB pneumonia, highlighting the main strengths and limitations of these assays, as well as the main factors influencing their clinical utility. We searched MEDLINE and Web of Science databases for relevant English-language articles. Molecular assays have higher analytical sensitivity than cultural methods, and show good agreement with standard-of-care diagnostics regarding detection of respiratory pathogens, including GNB, and identification of frequent patterns of resistance to antibiotics. Clinical trials reported encouraging results on the usefulness of molecular assays in antibiotic stewardship. By providing early information on the presence of pathogens and their probable resistance phenotypes, these assays assist in the choice of targeted therapy, in shortening the time from sample collection to appropriate antimicrobial treatment, and in reducing unnecessary antibiotic use.

Background and Aim: Bovine coccidiosis, caused by the protozoa Eimeria, is an important parasitic cattle disease that affects animal health and has economic impact worldwide. This study was conducted to report the first molecular prevalence and genetic diversity of Eimeria spp. in dairy cattle in Khon Kaen province, Thailand, and to identify the risk factors associated with Eimeria spp. infection. Materials and Methods: From July 2020 to October 2021, 296 fecal samples were collected from dairy cattle divided into three age groups, including 1-year-old cattle. Eimeria spp. were identified by multiplex polymerase chain reaction (PCR) amplifying 18S RNA gene and confirmed by DNA sequencing. Information regarding all associated risk factors was collected using questionnaires and analyzed using logistic regression tests in the Statistical Package for the Social Sciences program. Results: Polymerase chain reaction results showed that 104 (35.13%) of 296 samples were positive for Eimeria spp. The

We evaluated the impact of the FilmArray blood culture identification (BCID) panel on the time taken to administer effective antibiotics and the clinical outcomes of bloodstream infections. We retrospectively screened patients with bloodstream infections who underwent BCID testing and compared them to a historical control group that received conventional culture testing. A total of 144 and 214 patients who underwent BCID and conventional cultures, respectively, were compared. The 30-day mortality (BCID: 9.7% vs. conventional method: 10.7%, p = 0.755), time to effective antibiotic administration (3 h for both BCID and conventional method, p = 0.789), and time to appropriate antibiotic administration did not differ significantly between the groups. BCID was not significantly associated with 30-day mortality after adjusting for the Pitt bacteremia score and the Charlson comorbidity index (adjusted OR = 0.833, CI; 0.398–1.743). Compared with conventional methods, BCID reduced the time to administration of effective antibiotics in cases of carbapenem-resistant Enterobacterales (CRE) (39 h vs. 93 h, p = 0.012) and vancomycin-resistant enterococci (VRE) (50 h vs. 92 h, p < 0.001) bacteremia. BCID did not affect the clinical outcomes of overall bloodstream infections; however, it contributed to the early administration of effective antibiotics in cases of CRE and VRE bacteremia. [ABSTRACT FROM AUTHOR]

Background: Acute respiratory infections (ARIs) are an important cause of pediatric mortality–morbidity worldwide, the most common etiology being viral. This study aims to identify causative organisms for ARIs admitted in pediatric intensive care unit (PICU), when multiplex polymerase chain reaction (PCR) testing of respiratory secretions was sent; any seasonal trends detect microbiological correlation when co-infections. Subjects and Methods: This was a retrospective observational study, from July 2021 to December 2022, of children aged 1 month–18 years, whose multiplex PCR tests (nasopharyngeal, endotracheal [ET] secretion or bronchoscopic alveolar lavage [BAL]) were sent when admitted for ARI to tertiary care PICU. Results: In the study period, 372 of 1492 medical PICU admissions were ARI. Multiplex PCR of 81 respiratory secretions was sent, of which 69 (85%) were positive. Multiplex pcr sample positivity : 83% for nasopharyngeal aspirate, 78% for ET secretions, 100% for BAL samples. Forty-one percent of samples detected >1 organism. Respiratory syncytial virus (RSV)-A was the most common virus (18); other organisms included adenovirus (n = 5), influenza (n = 9), parainfluenza (n = 5), rhinovirus: 13, Pneumocystis Jerovecci (PCP): 4, Streptococcus pneumoniae: 17, pertussis: 1, and Haemophilus influenzae B: 9. ARIs were seen throughout the year with peaks in monsoon season and a peak in cases of ARI due to RSV from July to October. Of co-infections with bacteria in ET secretions and BAL samples via multiplex PCR, bacterial culture reports were sterile. Conclusions: Multiplex PCR detected organisms in 85% of ARI patients tested. Most of the ARIs getting admitted to PICU were viral in origin. RSV was the most common virus isolated showing peak from July to October, local monsoon season. With extended viral and bacterial PCR being available, mixed infections/colonization with uncertain significance are being detected. [ABSTRACT FROM AUTHOR]

Background and Objectives: Acinetobacter baumannii, an opportunistic pathogen, is related to hospital-acquired infections and increased mortality. This study aimed to develop the loop-mediated isothermal amplification (LAMP) test for the fast-detecting of A. baumannii isolates as well as determining genetic relatedness for these isolates via the REP-PCR technique. Materials and Methods: LAMP primers and multiplex PCR primers were designed for recognizing A. baumannii isolates harboring the blaSHV-1, blaPER-1, blaTEM-1, AMPC, qnr, and aac (6)-1 genes, were collected (October 2020 to February 2021) from Shahid Motahari Hospital, Tehran, Iran. Combination disc test (CDT) results were used to assess the phenotypic identification of isolates from ESBL producers. The sensitivity of the LAMP method was evaluated using a range of serial dilutions of genomic DNA. Results were compared between the LAMP technique, and multiplex PCR. The genetic diversity of clinical isolates was determined by REP-PCR. Results: Among one hundred A. baumannii samples and based on the combined disc test, 56% of isolates were ESBL producers. The sensitivity of the LAMP technique for the identification of A. baumannii was 4.06 ng/μl whilst the multiplex PCR was (16.2 ng/μl). Regarding multiplex PCR, (68%) of the isolates were blaSHV-1 positive, (40%) blaPER-1, (85%) aac (6)-1, AMPC (67%), blaTEM-1 (63%), and (15%) qnr respectively. While in LAMP, (69%) of isolates were bla positive, (86%) aac (6')-1, and (20%) qnr. The results of AMPC, blaTEM-1, and blaPER-1 genes showed 100% compatibility between multiplex PCR and LAMP assays. The results of REP-PCR indicated there were 17 clones, clone A at 14% was the most prevalent of the isolates. Conclusion: Wherever equipment and financial constraints are crucial, the LAMP test offers a better and more potent detection rate for the identification of A. baumannii isolates than multiplex PCR. Furthermore, the genetic diversity of A. baumannii in these clinical isolates showed frequent commonality of genotypes. [ABSTRACT FROM AUTHOR]

In this cohort study of 800 children attending a pediatric emergency department at Oulu University Hospital, Finland with fever or respiratory symptoms, the cycle threshold values of point-of-care multiplex polymerase chain reaction testing for respiratory viruses were not associated with hospitalization, respiratory support, or need for intensive care. [ABSTRACT FROM AUTHOR]

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Abstract Background Escherichia coli infections are common in Xinjiang, a major region of cattle and sheep breeding in China. Therefore, strategies are required to control E. coli. The aim of this study was to investigate the phylogenetic groups, virulence genes, and antibiotic resistance characteristics of E. coli isolates. Methods In this study, 116 tissue samples were collected from the organs of cattle and sheep that were suspected of having E. coli infections between 2015 and 2019. Bacteria in the samples were identified using a biochemical identification system and amplification of 16S rRNA, and the phylogenetic groupings of E. coli isolates were determined by multiplex polymerase chain reactions. In addition, PCR detection and analysis of virulence factors, antibiotic resistance genes, and drug‐resistant phenotypes of E. coli isolates were performed. Results A total of 116 pathogenic E. coli strains belonging to seven phylogenetic groups were isolated, with the majority of isolates in groups A and B1. Among the virulence genes, curli‐encoding crl had the highest detection rate of 97.4%, followed by hemolysin‐encoding hlyE with the detection rate of 94.82%. Antimicrobial susceptibility test results indicated that the isolates had the highest rates of resistance against streptomycin (81.9%). Conclusion These characteristics complicate the prevention and treatment of E. coli‐related diseases in Xinjiang.

Listeria monocytogenes is a rare cause of bacterial meningitis, particularly beyond the neonatal period. This article describes a 16-month-old girl who presented with a new-onset febrile status epilepticus, and subsequently developed altered mentality and lethargy. L. monocytogenes was detected on a point-of-care, multiplex polymerase chain reaction using the cerebrospinal fluid. On day 3, she developed a rapidly progressive hydrocephalus. Her consciousness improved after placement of an external ventricular drain. After 3-week antibiotic therapy, she was successfully discharged without residual complications.

To accurately identify the genes and pathways involved in the initiation of the Myxococcus xanthus multicellular developmental program, we have previously reported a method of growing vegetative populations as biofilms within a controllable environment. Using a modified approach to remove up to ~90% rRNAs, we report a comprehensive transcriptional analysis of the M. xanthus developmental cycle while comparing it with the vegetative biofilms grown in rich and poor nutrients. This study identified 1522 differentially regulated genes distributed within eight clusters during development. It also provided a comprehensive overview of genes expressed during a nutrient-stress response, specific development time points, and during development initiation and regulation. We identified several differentially expressed genes involved in key central metabolic pathways suggesting their role in regulating myxobacterial development. Overall, this study will prove an important resource for myxobacterial researchers to delineate the regulatory and functional pathways responsible for development from those of the general nutrient stress response.

Background: Community-Acquired Pneumonia (CAP) is the primary cause of hospitalization in the United States and the third leading cause of death in Brazil. The gold standard for diagnosing the etiology of CAP includes blood culture, Gram-stained sputum, and sputum culture. However, these methods have low sensitivity. No studies investigating the etiology of CAP have been conducted in Brazil in the last 20-years, and the empirical choice of antimicrobials is mainly based on the IDSA guidelines. This is the first national study with this aim, and as a result, there's potential for the Brazilian consensus to be impacted and possibly modify its guidelines rather than adhering strictly to the IDSA's recommendations. Methods: The aim of this study is to identify the main microorganisms implicated in CAP by employing a multiplex Polymerase Chain Reaction (mPCR) at the foremost public hospital in Brazil. All patients who were admitted to the emergency department and diagnosed with severe CAP underwent an mPCR panel using nasopharyngeal and oropharyngeal swabs, with the aim of detecting 13 bacterial and 21 viral pathogens. Results: A total of 169 patients were enrolled in the study. The mPCR panel identified an etiological agent in 61.5% of patients, with viruses being the most common (42.01%), led by Rhinovirus, followed by Influenza and Coronavirus (non-SARS-CoV-2). Bacterial agents were identified in 34.91% of patients, with S. pneumoniae being the most common, followed by H. influenzae, M. catarrhalis, and S. aureus. Additionally, we found that the prescription for 92.3% of patients could be modified, with most changes involving de-escalation of antibiotics and antiviral therapy. Conclusion: Our study revealed different etiological causes of CAP than those suggested by the Brazilian guidelines. Using molecular diagnostic tests, we were able to optimize treatment by using fewer antibiotics.

Background and Objectives: Acinetobacter baumannii, an opportunistic pathogen, is related to hospital-acquired infections and increased mortality. This study aimed to develop the loop-mediated isothermal amplification (LAMP) test for the fast-detecting of A. baumannii isolates as well as determining genetic relatedness for these isolates via the REP-PCR technique. Materials and Methods: LAMP primers and multiplex PCR primers were designed for recognizing A. baumannii isolates harboring the blaSHV-1, blaPER-1, blaTEM-1, AMPC, qnr, and aac (6)-1 genes, were collected (October 2020 to February 2021) from Shahid Motahari Hospital, Tehran, Iran. Combination disc test (CDT) results were used to assess the phenotypic identification of isolates from ESBL producers. The sensitivity of the LAMP method was evaluated using a range of serial dilutions of genomic DNA. Results were compared between the LAMP technique, and multiplex PCR. The genetic diversity of clinical isolates was determined by REP-PCR. Results: Among one hundred A. baumannii samples and based on the combined disc test, 56% of isolates were ESBL producers. The sensitivity of the LAMP technique for the identification of A. baumannii was 4.06 ng/μl whilst the multiplex PCR was (16.2 ng/μl). Regarding multiplex PCR, (68%) of the isolates were blaSHV-1 positive, (40%) blaPER-1, (85%) aac (6́)-1, AMPC (67%), blaTEM-1 (63%), and (15%) qnr respectively. While in LAMP, (69%) of isolates were blaSHV-1 positive, (86%) aac (6')-1, and (20%) qnr. The results of AMPC, blaTEM-1, and blaPER-1 genes showed 100% compatibility between multiplex PCR and LAMP assays. The results of REP-PCR indicated there were 17 clones, clone A at 14% was the most prevalent of the isolates. Conclusion: Wherever equipment and financial constraints are crucial, the LAMP test offers a better and more potent detection rate for the identification of A. baumannii isolates than multiplex PCR. Furthermore, the genetic diversity of A. baumannii in these clinical isolates showed frequent commonality of genotypes.

Background and Aim: Bovine coccidiosis, caused by the protozoa Eimeria, is an important parasitic cattle disease that affects animal health and has economic impact worldwide. This study was conducted to report the first molecular prevalence and genetic diversity of Eimeria spp. in dairy cattle in Khon Kaen province, Thailand, and to identify the risk factors associated with Eimeria spp. infection. Materials and Methods: From July 2020 to October 2021, 296 fecal samples were collected from dairy cattle divided into three age groups, including <3-month-old calves, 3-month-old to 1-year-old calves, and >1-year-old cattle. Eimeria spp. were identified by multiplex polymerase chain reaction (PCR) amplifying 18S RNA gene and confirmed by DNA sequencing. Information regarding all associated risk factors was collected using questionnaires and analyzed using logistic regression tests in the Statistical Package for the Social Sciences program. Results: Polymerase chain reaction results showed that 104 (35.13%) of 296 samples were positive for Eimeria spp. The <3-month-old calves (46.51%) had the highest infection rate. Moreover, multiplex PCR identified five species of Eimeria, namely, Eimeria bovis (32.69%), Eimeria zuernii (18.26%), Eimeria alabamensis (5.76%), Eimeria ellipsoidalis (3.84%), and Eimeria cylindrica (2.88%). An association was observed between risk factors and Eimeria spp. incidence (p < 0.05). DNA sequencing revealed the similarity of each Eimeria spp. with 91%-100% nucleotide identity. Phylogenetic tree analysis demonstrated the close relationships of clusters of E. bovis and E. zuernii, E. ellipsoidalis, and E. cylindrica and another cluster of E. alabamensis. Conclusion: The results confirm that Eimeria spp. are commonly found in dairy cattle, especially calves. The molecular test could be powerful for species identification. This study also provides epidemiological information for developing future strategies to control bovine coccidiosis. [ABSTRACT FROM AUTHOR]

Background: When children have a preoperative fever, anesthesiologists must help determine whether to postpone or proceed with surgery, as fever may be a sign of upper respiratory tract infection (URTI). Such infections are a known risk factor for perioperative respiratory adverse events (PRAEs), which are still one of the prime causes of anesthetic mortality and morbidity in pediatric patients. Since the COVID‐19 pandemic, preoperative assessments have become drastically more complex as hospitals strive to balance practicality and safety. In our facility, if pediatric patients presented with preoperative fever, we used the FilmArray® Respiratory Panel 2.1 to determine whether to postpone or proceed with surgery. Methods: This is a single‐center retrospective observational study evaluating the efficacy of the FilmArray® Respiratory Panel 2.1 as a preoperative screening test. This study included pediatric patients scheduled for elective surgeries between March 2021 and February 2022. FilmArray was used if a patient had a preoperative fever (determined by axillary temperature, ≥38°C for <1‐year‐old, ≥37.5°C for ≥1‐year‐old) between hospital admission and before surgery. We excluded patients if they had apparent symptoms of URTI. Results: In the FilmArray positive group, 11 of 25 (44%) cases developed subsequent symptoms after surgery was canceled. No patients in the negative group developed symptoms. The proportion of the development of subsequent symptoms between the FilmArray positive and negative groups was statistically significant (p <.001, odds ratio: 29.6, 95% confidence interval: [3.80–1356.01]). Conclusions: Our retrospective observational study revealed that 44% of the FilmArray positive group subsequently developed symptoms, and no PRAEs were observed in the FilmArray negative group. We suggest that FilmArray could be useful as a screening test for pediatric patients with preoperative fever. [ABSTRACT FROM AUTHOR]

We developed and assessed the performance of a new multiplex real-time PCR assay for the detection of all Chlamydia species and simultaneous differentiation of Chlamydia psittaci and Chlamydia pneumoniae--two important human respiratory pathogens--in human clinical specimens. Next-generation sequencing was used to identify unique targets to design real-time PCR assays targeting all Chlamydia species, C. psittaci, and C. pneumoniae. To validate the assay, we used a panel of 49 culture isolates comprising seven C. psittaci genotypes, eight C. pneumoniae isolates, seven other Chlamydia species, and 22 near-neighbor bacterial and viral isolates, along with 22 specimens from external quality assessment (EQA) panels and 34 nasopharyngeal and oropharyngeal swabs and cerebrospinal fluid, stool, and sputum specimens previously identified as positive or negative for C. psittaci or C. pneumoniae. The assays were 100% specific, with limits of detection of 7.64-9.02 fg/µL. The assay results matched with historical assay results for all specimens, except for one owing to the increased sensitivity of the new C. psittaci assay; the results of the EQA specimens were 100% accurate. This assay may improve the timely and accurate clinical diagnosis of Chlamydia infections and provide a greater understanding of the burden of disease caused by these agents. [ABSTRACT FROM AUTHOR]

Emulsions offer the means to miniaturize and parallelize high-throughput screening but require a robust method to localize activity-based fluorescent probes in each droplet. Multiplexing probes in droplets is impractical, though highly desirable for identifying library members that possess very specific activity. Here, we present multiplexed probe immobilization on library beads for emulsion screening. During library bead preparation, we quantitated ∼106 primers per bead by fluorescence in situ hybridization, however emulsion PCR yielded only ∼103 gene copies per bead. We leveraged the unextended bead-bound primers to hybridize complementary probe-oligonucleotide heteroconjugates to the library beads. The probe-hybridized bead libraries were then used to program emulsion in vitro transcription/translation reactions and analyzed by FACS to perform multiplexed activity-based screening of trypsin and chymotrypsin mutant libraries for novel proteolytic specificity. The approach's modularity should permit a high degree of probe multiplexing and appears extensible to other enzyme classes and library types.

Malaria antigen detection through rapid diagnostic tests (RDTs) is widely used to diagnose malaria and estimate prevalence. To support more sensitive next-generation RDT development and screen asymptomatic malaria, we developed and evaluated the Q-Plex™ Human Malaria Array (Quansys Biosciences, Logan, UT), which quantifies the antigens commonly used in RDTs-Plasmodium falciparum-specific histidine-rich protein 2 (HRP2), P. falciparum-specific lactate dehydrogenase (Pf LDH), Plasmodium vivax -specific LDH (Pv LDH), and Pan malaria lactate dehydrogenase (Pan LDH), and human C-reactive protein (CRP), a biomarker of severity in malaria. At threshold levels yielding 99.5% or more diagnostic specificity, diagnostic sensitivities against polymerase chain reaction-confirmed malaria for HRP2, Pf LDH, Pv LDH, and Pan LDH were 92.7%, 71.5%, 46.1%, and 83.8%, respectively. P. falciparum culture strains and samples from Peru indicated that HRP2 and Pf LDH combined improves detection of P. falciparum parasites with hrp2 and hrp3 deletions. This array can be used for antigen-based malaria screening and detecting hrp2/3 deletion mutants of P. falciparum.

A microbial imbalance called dysbiosis leads to inflammatory bowel disease (IBD), which can include ulcerative colitis (UC). Fecal microbiota transplantation (FMT), a novel therapy, has recently been successful in treating gut dysbiosis in UC patients. For the FMT technique to be successful, the gut microbiota of both the healthy donors and UC patients must be characterized. For decades, next-generation sequencing (NGS) has been used to analyze gut microbiota. Despite the popularity of NGS, the cost and time constraints make it difficult to use in emergency services and activities related to the periodic monitoring of microbiota profile alterations. Hence, in this study, we developed a multiplex TaqMan qPCR assay (MTq-PCR) with novel probes to simultaneously determine the relative proportions of the three dominant microbial phyla in the human gut: Bacteroidetes, Firmicutes, and Proteobacteria. The relative proportions of the three phyla in fecal samples of either healthy volunteers or UC patients were similar when assessed NGS and the MTq-PCR. Thus, our MTq-PCR assay could be a practical microbiota profiling alternative for diagnosing and monitoring gut dysbiosis in UC patients during emergency situations, and it could have a role in screening stool from potential FMT donors.

ObjectiveA growing body of evidence suggests that testing for influenza virus alone is more appropriate than multiplex respiratory viral panel (RVP) testing for general populations of patients with respiratory tract infections. We aimed to decrease the proportion of RVPs out of total respiratory viral testing ordered during influenza season.MethodsWe implemented two consecutive interventions: reflex testing for RVPs only after a negative influenza test, and noninterruptive clinical decision support (CDS) including modifications of the computerized physician order entry search behavior and cost display. We conducted an interrupted time series of RVPs and influenza polymerase chain reaction tests pre- and postintervention, and performed a mixed-effects logistic regression analysis with a primary outcome of proportion of RVPs out of total respiratory viral tests. The primary predictor was the intervention period, and covariates included the provider, clinical setting, associated diagnoses, and influenza incidence.ResultsFrom March 2013 to April 2019, there were 24,294 RVPs and 26,012 influenza tests (n = 50,306). Odds of ordering an RVP decreased during the reflex testing period (odds ratio: 0.432, 95% confidence interval: 0.397-0.469), and decreased more dramatically during the noninterruptive CDS period (odds ratio: 0.291, 95% confidence interval: 0.259-0.327).DiscussionThe odds of ordering an RVP were 71% less with the noninterruptive CDS intervention, which projected 4,773 fewer RVPs compared with baseline. Assuming a cost equal to Medicare reimbursement rates for RVPs and influenza tests, this would generate an estimated averted cost of $1,259,474 per year.ConclusionNoninterruptive CDS interventions are effective in reducing unnecessary and expensive testing, and avoid typical pitfalls such as alert fatigue.

In light of the current biodiversity crisis, molecular barcoding has developed into an irreplaceable tool. Barcoding has been considerably simplified by developments in high throughput sequencing technology, but still can be prohibitively expensive and laborious when community samples of thousands of specimens need to be processed. Here, we outline an Illumina amplicon sequencing approach to generate multilocus data from large collections of arthropods. We reduce cost and effort up to 50-fold, by combining multiplex PCRs and DNA extractions from pools of presorted and morphotyped specimens and using two levels of sample indexing. We test our protocol by generating a comprehensive, community wide dataset of barcode sequences for several thousand Hawaiian arthropods from 14 orders, which were collected across the archipelago using various trapping methods. We explore patterns of diversity across the Archipelago and compare the utility of different arthropod trapping methods for biodiversity explorations on Hawaii, highlighting undergrowth beating as highly efficient method. Moreover, we show the effects of barcode marker, taxonomy and relative biomass of the targeted specimens and sequencing coverage on taxon recovery. Our protocol enables rapid and inexpensive explorations of diversity patterns and the generation of multilocus barcode reference libraries across whole ecosystems.