Feng-yee Chang
National defense medical center, Department of medicine, Faculty Member
Research Interests: Microbiology, Biology, Medicine, Molecular Epidemiology, Humans, and 15 moreMultidrug Resistance, Taiwan, Clinical, DNA fingerprinting, Integron, Clinical Sciences, Integrons, Genotype, Bacteremia, Microbial Sensitivity Tests, Acinetobacter baumannii, Imipenem, Acinetobacter Infections, Beta Lactamases, and Multiple Drug Resistance
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Background and purpose: Vancomycin-resistant enterococci (VRE) have emerged as important nosocomial pathogens. This study was conducted to clarify the clinical features and outcome of patients with vancomycin-resistant enterococcal... more
Background and purpose: Vancomycin-resistant enterococci (VRE) have emerged as important nosocomial pathogens. This study was conducted to clarify the clinical features and outcome of patients with vancomycin-resistant enterococcal bacteremia. Methods: Patients with vancomycin-resistant enterococcal bacteremia treated at a medical center in northern Taiwan between November 1998 and July 2006 were reviewed. Clinical and bacteriological characteristics of Enterococcus faecium and Enterococcus faecalis were compared. Results: Twelve patients (6 males and 6 females) were included for analyses. The mean age was 69.3 years (range, 40 to 86 years), and 8 cases (66.7%) were older than 65 years. All patients had underlying disease. Two patients received total hip replacement before development of VRE bacteremia. Twelve patients had prior exposure to broad-spectrum antimicrobial therapy. Ten patients had prior intensive care unit stay and prior mechanical ventilation before VRE bacteremia. All of the patients (n = 12) had an intravascular catheter in place. Bacteremia was caused by E. faecalis in 4 patients and by E. faecium in eight. The portals of entry included urinary tract (8.3%), skin, soft tissue and bone (41.7%) and unknown sources (50.0%). E. faecium showed a higher rate of resistance to ampicillin and teicoplanin than E. faecalis (87.5% vs 0.0%, p=0.01). The 60-day mortality rate was higher in patients with E. faecium bacteremia than E. faecalis bacteremia (62.5% vs 0.0%), although statistical significance was not obtained (p=0.08). Conclusions: VRE bacteremia may have an impact on the mortality and morbidity of hospitalized patients. Patients with bacteremia caused by vancomycin-resistant E. faecium had a grave prognosis, especially immunosuppressed patients. The prudent use of antibiotics and strict enforcement of infection control may prevent further emergence and spread of VRE.
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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a pandemic. Additionally, several SARS-CoV-2 variants have continuously challenged diagnostic testing due to viral diversity in spike and nucleocapsid (N) protein... more
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a pandemic. Additionally, several SARS-CoV-2 variants have continuously challenged diagnostic testing due to viral diversity in spike and nucleocapsid (N) protein mutations. SARS-CoV-2-variant proliferation potentially affects N protein-targeted rapid antigen testing. We performed rapid antigen and reverse transcription polymerase chain reaction (RT-PCR) tests simultaneously in patients with suspected coronavirus disease 2019 (COVID-19). To determine the N protein variations, direct whole-genome sequencing was performed, and the viral assemblies were uploaded to GISAID. We compared their genomes with those of global virus strains from GISAID. These isolates belonged to the B.1.1.7 variant, exhibiting several amino acid substitutions, including D3L, R203K, G204R, and S235F N protein mutations. We also identified the T135I mutation in one variant case in which rapid antigen and RT-PCR tests were discordantly negative and positive, respectively. Our findings suggest that the variants undetected by the PanbioTM COVID-19 rapid antigen test may be due to N-protein T135I mutations, posing a potential diagnostic risk to commercially available antigen tests. Hence, we recommend concomitant paired rapid antigen tests and molecular diagnostic methods to detect SARS-CoV-2. False-negative results could be rapidly corrected using confirmatory RT-PCR results to prevent future COVID-19 outbreaks.
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Background and purpose: Pneumocystis jirovecii pneumonia is an opportunistic infection capable of causing life-threatening pneumonia in immunocompromised patients. To elucidate the clinical presentation and outcome of this disease in... more
Background and purpose: Pneumocystis jirovecii pneumonia is an opportunistic infection capable of causing life-threatening pneumonia in immunocompromised patients. To elucidate the clinical presentation and outcome of this disease in Taiwan, we analyzed the patients with P. jirovecii pneumonia during a 34-month period. Methods: We collected data retrospectively from patients with P. jirovecii pneumonia at a medical center in northern Taiwan between January 2004 and October 2006. The diagnosis was made by nested polymerase chain reaction (PCR) analysis of expectorated sputum. Demographics, clinical characteristics, laboratory findings, and outcomes were compared between patients with and without human immunodeficiency virus (HIV) infection. Results: Forty nine patients were included in this study. The most common underlying diseases were HIV and malignancies. The mean (+/- standard deviation) age of the 49 patients was 54 +/- 20.2 years (range, 5 to 96 years). The mean CD4+ T-lymphocyte count was 110 cells/microL (range, 0-670 cells/microL). Although the mean CD4+ T-lymphocyte count of the non-HIV group was higher than that of the HIV group (165 +/- 78 cells/microL vs 57.5 +/- 97 cells/microL), statistical significance was not obtained (p=0.087). Arterial oxygenation (ratio of arterial oxygenation to fraction of inspired oxygen) was less than 200 mm Hg in 28 patients. Lactate dehydrogenase levels were higher than the normal range in 15 patients. A significantly higher proportion of patients died in the group without HIV compared with the HIV-infected patients (17/34 [50.0%] vs 1/15 [6.7%]; p=0.004). Conclusion: P. jirovecii pneumonia remains a significant problem for immunocompromised patients. The mortality rate for patients without HIV infection was high (50%). Greater alertness with regard to early detection of P. jirovecii in HIV-negative immunosuppressed patients with the application of nested PCR may improve the clinical management and outcome.
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Background. The purpose of this prospective, randomized study was to compare the efficacy of single‐dose versus 1‐day cefazolin prophylaxis for the prevention of postoperative gynecologic infections.Methods. From June 2001 to January... more
Background. The purpose of this prospective, randomized study was to compare the efficacy of single‐dose versus 1‐day cefazolin prophylaxis for the prevention of postoperative gynecologic infections.Methods. From June 2001 to January 2003, 548 patients were randomized to receive either single‐dose (1 g of cefazolin intravenously before surgery, 273 patients) or 1‐day cefazolin (1 g intravenously before surgery and three more doses every 6 hr after surgery, 275 patients) prophylaxis.Results. A total of 531 (267 patients in the single‐dose group and 264 in the 1‐day group) completed the study. Only one of 267 (0.37%) patients in the single‐dose group developed a trocar wound infection and one of 264 (0.37%) patients in the 1‐day group developed a vaginal cuff infection. Had a single dose of prophylactic antibiotics been administered to all patients, the antibiotic cost would have been reduced by 75–80%.Conclusions. The use of single‐dose preoperative cefazolin prophylaxis was as effective as four doses of cefazolin for preventing serious infectious morbidity among our patients. Shortening the duration of antibiotics prophylaxis also reduced medical costs and microorganism resistance.
Research Interests: Surgery, Treatment Outcome, Medicine, Prospective studies, Humans, and 15 moreFemale, Anesthesia, Antibiotic Prophylaxis, Hysterectomy, Antibiotics, Middle Aged, Adult, Public health systems and services research, Randomized Controlled Trial, Cost Benefit Analysis, Ovarian cysts, Prospective Cohort Study, Surgical wound infection, Cefazolin, and Paediatrics and reproductive medicine
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Background and aims Immediate detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical for preventing the spread of coronavirus disease 2019 (COVID-19). The LabTurbo AIO 48 system is an automated platform that... more
Background and aims Immediate detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical for preventing the spread of coronavirus disease 2019 (COVID-19). The LabTurbo AIO 48 system is an automated platform that allows nucleic acid extraction and sample analysis on the same instrument, producing faster results without affecting their accuracy. We aimed to independently evaluate the LabTurbo AIO 48 (all-in-one system) for SARS-CoV-2 detection. Materials and methods Comparative limit of detection (LOD) was assessed on both the LabTurbo AIO 48 and current standard detection system based on real-time reverse transcriptase polymerase chain reaction (RT-PCR), using SARS-CoV-2 RNA control. Additional 125 primary clinical samples were assessed using both the protocols in parallel. Results The turnaround time from sample to results for 48 samples analyzed on LabTurbo AIO 48 was approximately 2.5 h, whereas that analyzed using the in-house RT-PCR protocol was 4.8 h. LabTurbo AIO 48 also demonstrated higher sensitivity than our reference RT-PCR assay, with a LOD of 9.4 copies/reaction. The overall percentage agreement between both the methods for 125 samples was 100%. Conclusion LabTurbo AIO 48 is a robust detection option for SARS-CoV-2, allowing faster results and, consequently, aiding in better control and prevention of COVID-19.
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This is the first nationwide study to examine the seroepidemiology of Klebsiella pneumoniae using blood culture isolates collected over a period of 20 years. The study found that the prevalence of serotypes remained consistent over the... more
This is the first nationwide study to examine the seroepidemiology of Klebsiella pneumoniae using blood culture isolates collected over a period of 20 years. The study found that the prevalence of serotypes remained consistent over the 20-year period, with high-prevalence serotypes associated with invasive types.
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The prevalence of community-acquired infection caused by methicillin-resistant Staphylococcus aureus (MRSA) in Taiwan has increased markedly in the past decade. This study investigated the risk factors for acquisition, the clinical... more
The prevalence of community-acquired infection caused by methicillin-resistant Staphylococcus aureus (MRSA) in Taiwan has increased markedly in the past decade. This study investigated the risk factors for acquisition, the clinical features, and the outcome of community-acquired MRSA bacteremia. Data were collected from records of 86 patients with community-acquired S. aureus bacteremia admitted to a tertiary teaching hospital in Taipei from January 1994 to December 1999. MRSA accounted for 26% (22/86) of isolated pathogens. Over 90% of patients with S. aureus bacteremia had one or more underlying diseases. Significantly more patients with MRSA bacteremia [vs methicillin-susceptible S. aureus (MSSA) bacteremia] had congenital and valvular heart diseases (18% vs 0%, p=0.004), an initial presentation of acute respiratory failure (32% vs 11%, p=0.022), an implant as a portal of entry (9% vs 0%, p=0.014), and mortality (41% vs 20%, p=0.05). Acute Physiology and Chronic Health Evaluation (APACHE) III score was significantly higher in patients who died than in patients who survived in both the MRSA and MSSA bacteremia groups. Inappropriate treatment was more frequent in patients with MRSA bacteremia than in MSSA bacteremia. When a Gram-positive coccemia is initially noted in a patient with high APACHE III score and/or acute respiratory failure, early and aggressive treatment including glycopeptide should be considered.
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Coronavirus Disease 2019 (COVID-19), caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), is an ongoing pandemic. Detection and vaccination are essential for disease control, but they are distinct and complex operations... more
Coronavirus Disease 2019 (COVID-19), caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), is an ongoing pandemic. Detection and vaccination are essential for disease control, but they are distinct and complex operations that require significant improvements. Here, we developed an integrated detection and vaccination system to greatly simplify these efforts. We constructed recombinant baculoviruses to separately display the nucleocapsid (N) and spike (S) proteins of SARS-CoV-2. Insect cells infected by the recombinant baculoviruses were used to generate a cell-based system to accurately detect patient serum. Notably, although well-recognized by our newly developed detection system in which S-displaying insect cells acted as antigen, anti-S antibodies from many patients were barely detectable by Western blot, evidencing that COVID-19 patients primarily produce conformation-dependent anti-S antibodies. Furthermore, the same baculovirus constructs can display N (N-Bac...
Research Interests: Virology, Medicine, Serology, Vaccination, Recombinant DNA, and 3 moreAntibody, Antigen, and Adjuvant
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The molecular epidemiology and resistance mechanisms of mcr -negative colistin-resistant E. coli are not well described. In this study, a total of 11 mcr -negative colistin-resistant E. coli isolates were selected from a nationwide... more
The molecular epidemiology and resistance mechanisms of mcr -negative colistin-resistant E. coli are not well described. In this study, a total of 11 mcr -negative colistin-resistant E. coli isolates were selected from a nationwide antimicrobial resistance surveillance program in Taiwan for further investigation.
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New variants of the influenza A(H1N1)pdm09 and A(H3N2) viruses were detected in Taiwan between 2012 and 2013. Some of these variants were not detected in clinical specimens using a common real-time reverse transcription-PCR (RT-PCR) assay... more
New variants of the influenza A(H1N1)pdm09 and A(H3N2) viruses were detected in Taiwan between 2012 and 2013. Some of these variants were not detected in clinical specimens using a common real-time reverse transcription-PCR (RT-PCR) assay that targeted the conserved regions of the viral matrix (M) genes. An analysis of the M gene sequences of the new variants revealed that several newly emerging mutations were located in the regions where the primers or probes of the real-time RT-PCR assay bind; these included three mutations (G225A, T228C, and G238A) in the A(H1N1)pdm09 virus, as well as one mutation (C163T) in the A(H3N2) virus. These accumulated mismatch mutations, together with the previously identified C154T mutation of the A(H1N1)pdm09 virus and the C153T and G189T mutations of the A(H3N2) virus, result in a reduced detection sensitivity for the real-time RT-PCR assay. To overcome the loss of assay sensitivity due to mismatch mutations, we established a real-time RT-PCR assay ...
Research Interests: Biology, Virology, Medicine, Clinical Microbiology, Biological Sciences, and 14 moreHumans, Mutation, Virus, Taiwan, Gene, influenza A virus, Molecular Diagnostic Techniques, Sensitivity and Specificity, Reverse Transcriptase, Molecular Sequence Data, real time polymerase chain reaction, reverse transcriptase polymerase chain reaction, Reverse transcription polymerase chain reaction, and Medical and Health Sciences
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Objectives : With the emergence of the B.1.1.7 lineage in the ongoing COVID-19 pandemic, Taiwan confronted a COVID-19 flare up in May 2021. Large-scale, accurate, affordable, and rapid diagnostic tests such as the lateral flow assay can... more
Objectives : With the emergence of the B.1.1.7 lineage in the ongoing COVID-19 pandemic, Taiwan confronted a COVID-19 flare up in May 2021. Large-scale, accurate, affordable, and rapid diagnostic tests such as the lateral flow assay can help prevent community transmission, but their performance characteristics in real-world conditions and relevant subpopulations remain unclear. Methods : The COVID-19 Antigen Rapid Test kit (Eternal Materials, New Taipei City, Taiwan) was used in a high-throughput community testing site; the paired reverse-transcription polymerase chain reaction (RT-PCR) results served as a reference for sensitivity and specificity calculations. Results : Of 2,096 specimens tested using the rapid antigen tests, 70 (3.33%) were positive and 2,026 (96.7%) were negative. This clinical performance was compared with the RT-PCR results. The sensitivity and specificity of the rapid SARS-CoV-2 antigen detection test were 76.39% (95% CI, 64.91–85.60%) and 99.26% (95% CI, 98.78–99.58%), respectively, with high sensitivity in subjects with threshold cycle ≤24. Further, the COVID-19 Antigen Rapid Test kit effectively detected the SARS-CoV-2 B.1.1.7 lineage. Conclusions : Considering the short turnaround times and lower costs, this simple SARS-CoV-2 antigen detection test for rapid screening combined with RT-PCR as a double confirmatory screening tool can facilitate the prevention of community transmission during COVID-19 emergencies.
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A total of 50 engineered strains with various resistance mechanisms from two fully susceptible strains, Acinetobacter baumannii KAB1544 and ATCC 17978, were constructed by in-frame deletion, site-directed mutagenesis and plasmid... more
A total of 50 engineered strains with various resistance mechanisms from two fully susceptible strains, Acinetobacter baumannii KAB1544 and ATCC 17978, were constructed by in-frame deletion, site-directed mutagenesis and plasmid transformation. These strains included 31 strains with chromosome-mediated resistance and 19 strains with plasmid-mediated resistance, and each of the 50 resistance mechanisms showed similar effects on the MICs for KAB1544 and ATCC 17978. Compared to the parental strains, the engineered strains related to some efflux pumps showed a significant (≥4-fold) difference in the MICs of β-lactams, quinolones, aminoglycosides, tetracyclines, folate pathway inhibitors and/or phenicols, while no significant (≥4-fold) effects on the MICs were found for the engineered strains lacking OmpA, CarO, Omp25, Omp33, OmpW or OprD. Mechanisms due to GyrA/ParC mutations, β-lactamase, aminoglycoside-modifying enzyme, 16S rRNA methylase and tet resistance gene contributed their corresponding resistance, as previously published. In conclusion, strains constructed in this study have clear resistance mechanisms and can be used to screen and assess compounds against specific resistance mechanisms for treating Acinetobacter. In addition to our previously published system for Enterobacteriaceae, the combination of these two systems could increase the coverage of bacterial types for drug assessment and facilitate the selection process of new candidates in the drug development against superbugs.
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Research Interests: Microbiology, Epidemiology, Biology, Medicine, Molecular Epidemiology, and 15 moreHumans, Infection Control, Polymerase Chain Reaction, Research article, multiplex PCR, Phenotype, Genotype, Enterococcus, Feces, Microbial Sensitivity Tests, Serotyping, Rectum, Cross Infection, multiplex polymerase chain reaction, and Population surveillance
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Research Interests: Adolescent, Medicine, Comorbidity, Biological Sciences, Humans, and 15 moreInternal Medicine, Hospitalization, Female, Pneumonia, Male, Etiology, Clinical Sciences, Chlamydia, Aged, Middle Aged, Adult, Community Acquired Pneumonia, Mycoplasma pneumoniae, Medical and Health Sciences, and Cardiovascular medicine and haematology
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Brain abscess is a life-threatening infection caused by spread from infected parameningeal or remote foci. Historically, streptococci have been the predominant organisms reported while brain abscess metastatic from liver abscess caused by... more
Brain abscess is a life-threatening infection caused by spread from infected parameningeal or remote foci. Historically, streptococci have been the predominant organisms reported while brain abscess metastatic from liver abscess caused by Klebsiella pneumoniae has been a more recent emerging problem. This study retrospectively analyzed the characteristics of community-acquired brain abscess admitted during an 11-year period. There were 17 men and 7 women with age from 20 to 82 years (median, 41 years). The most common source of infection was liver abscess, followed by otitic infection and sinusitis. The classic triad of fever, headache and focal neurologic deficit was noted in only 25% of cases. Spread of the abscess to multiple lobes was common (n = 6). The most commonly identified organisms were Streptococcus spp. (n = 7) and K. pneumoniae (n = 5). All 5 cases of K. pneumoniae brain abscess also had concomitant pyogenic liver abscess and 4 of them had diabetes mellitus. In this study, brain abscess was common in young patients and in patients with diabetes mellitus. In Taiwan, Streptococcus spp. and K. pneumoniae are leading etiologies for community-acquired brain abscess. Liver abscess is the most likely source of K. pneumoniae brain abscess.
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BACKGROUND/PURPOSE Outer membrane proteins (Omps) are a family of proteins that are highly conserved throughout the evolution of Enterobacteriaceae. Previous studies using sequence comparisons have found a high degree of sequence homology... more
BACKGROUND/PURPOSE Outer membrane proteins (Omps) are a family of proteins that are highly conserved throughout the evolution of Enterobacteriaceae. Previous studies using sequence comparisons have found a high degree of sequence homology between OmpK36 of Klebsiella pneumoniae and OmpC of Salmonella enterica serovar Typhi. Whether highly conserved OmpC can be directly extrapolated as a common vaccine candidate against K. pneumoniae or other Enterobacteriaceae remains to be verified. METHODS OmpK36 and OmpC were purified and used to immunize BALB/c mice. After immunization, five mice from each group were injected intraperitoneally with a cell suspension of K. pneumoniae or S. Typhi, and the mice were monitored daily for 14 days to measure the severity of illness and assess their survival. RESULTS Cross-reacting OmpK36 and OmpC antibodies were identified in the mice immunized with OmpK36 or OmpC. No cross-protection was observed in the mice immunized with OmpC in the presence of K. pneumoniae infection. CONCLUSION Although a high degree of similarity was observed for the amino acid sequences between OmpK36 and OmpC, our results suggested that no cross-protection occurred in the mice challenged with other species.
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COVID-19 has spread globally. SARS-CoV-2 variants of concern (VOCs) are leading the next waves of the COVID-19 pandemic.
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Background There is a global pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Information on viral genomics is crucial for understanding global dispersion and for providing insight into viral pathogenicity and... more
Background There is a global pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Information on viral genomics is crucial for understanding global dispersion and for providing insight into viral pathogenicity and transmission. Here, we characterized the SARS-CoV-2 genomes isolated from five travelers who returned to Taiwan from the United States of America (USA) between March and April 2020. Methods Haplotype network analysis was performed using genome-wide single-nucleotide variations to trace potential infection routes. To determine the genetic variations and evolutionary trajectory of the isolates, the genomes of isolates were compared to those of global virus strains from GISAID. Pharyngeal specimens were confirmed to be SARS-CoV-2-positive by RT-PCR. Direct whole-genome sequencing was performed, and viral assemblies were subsequently uploaded to GISAID. Comparative genome sequence and single-nucleotide variation analyses were performed. Results The D614G m...
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Background: Two different types of hypervirulent K. pneumoniae (HvKp), including MLST-11 or serotype K1/K2 strains, have been frequently described in recent studies. Although these two types of strains were described as HvKp, their... more
Background: Two different types of hypervirulent K. pneumoniae (HvKp), including MLST-11 or serotype K1/K2 strains, have been frequently described in recent studies. Although these two types of strains were described as HvKp, their virulence was not compared. In this study, an in vitro and in vivo approach was used to assess differences in virulence.Materials and Methods: A total of nine isolates, including one strain of serotype K1 isolate, two strains of serotype K2 isolates and six strains of ST11 isolates, were selected for this study. Phenotypic tests of virulence and associated genes were performed by string test, PCR, and in vitro models of serum resistance and phagocytosis.Results: Although serotype K2 strains and ST11 isolates had similar virulence gene profiles, the ST11 isolates showed less serum and phagocytic resistance than did serotype K1/K2 isolates. The mouse lethality test revealed that all 11 ST isolates were unable to cause lethality, even with > 107 CFU, whil...
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Actinomycosis is a chronic, suppurative, granulomatous diseases characterized by extensive necrosis and abscess formation. Both hepatic and pelvic actinomycosis are rare diseases. Tubo-ovarian actinomycosis complicated with hepatic... more
Actinomycosis is a chronic, suppurative, granulomatous diseases characterized by extensive necrosis and abscess formation. Both hepatic and pelvic actinomycosis are rare diseases. Tubo-ovarian actinomycosis complicated with hepatic abscess is rarely reported. We present a 47 year old woman with a history of an intrauterine device (IUD) implantation for about 18 years, who presented with epigastric pain for one month. A computed tomography (CT) scan of abdomen revealed a mass (13×10×9.6 cm) over the left lobe of the liver and a right-sided tubo-ovarian lesion (6.6×5.9 cm). Exploratory laparotomy confirmed liver and tubo-ovarian abscesses. Pathology of the liver and the tubo-ovarian lesions both revealed actinomycosis infection. The patient received a 4-week intravenous ampicillin treatment, followed by oral amoxicillin for 6 months. No recurrence was noted in the follow-up. Actinomycosis should be considered in concomitant liver and ovary abscesses. Detailed history taking, such as I...
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Background/Purpose Mass screening for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is important to prevent the spread of coronavirus disease 2019 (COVID-19). Pooling samples can increase the number of tests processed.... more
Background/Purpose Mass screening for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is important to prevent the spread of coronavirus disease 2019 (COVID-19). Pooling samples can increase the number of tests processed. LabTurbo AIO 48 is an automated platform that allows ribonucleic acid extraction and sample analysis on the same instrument. We created a novel pooling assay on this platform for SARS-CoV-2 detection and demonstrated that the pooling strategy increases testing capacity without affecting accuracy and sensitivity. Methods Comparative limit of detection (LoD) assessment was performed on the LabTurbo AIO 48 platform and the current standard detection system based on real-time reverse transcription polymerase chain reaction (rRT-PCR) using 55 clinically positive samples. An additional 330 primary clinical samples were assessed. Results Six samples pooled into one reaction tube were detected in approximately 2.5 h using the World Health Organization rRT-PCR protocol. LabTurbo AIO 48 also demonstrated a higher throughput than our reference rRT-PCR assay, with an LoD of 1000 copies/mL. The overall percentage agreement between the methods for the 330 samples was 100%. Conclusion We created a novel multi-specimen pooling assay using LabTurbo AIO 48 for the robust detection of SARS-CoV-2, allowing high-throughput results; this assay will aid in better control and prevention of COVID-19. The diagnostic assay was cost-effective and time-efficient; thus, the pooling strategy is a practical and effective method for diagnosing large quantities of specimens without compromising precision.
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Brain abscess is a life-threatening infection caused by spread from infected parameningeal or remote foci. Historically, streptococci have been the predominant organisms reported while brain abscess metastatic from liver abscess caused by... more
Brain abscess is a life-threatening infection caused by spread from infected parameningeal or remote foci. Historically, streptococci have been the predominant organisms reported while brain abscess metastatic from liver abscess caused by Klebsiella pneumoniae has been a more recent emerging problem. This study retrospectively analyzed the characteristics of community-acquired brain abscess admitted during an 11-year period. There were 17 men and 7 women with age from 20 to 82 years (median, 41 years). The most common source of infection was liver abscess, followed by otitic infection and sinusitis. The classic triad of fever, headache and focal neurologic deficit was noted in only 25% of cases. Spread of the abscess to multiple lobes was common (n = 6). The most commonly identified organisms were Streptococcus spp. (n = 7) and K. pneumoniae (n = 5). All 5 cases of K. pneumoniae brain abscess also had concomitant pyogenic liver abscess and 4 of them had diabetes mellitus. In this st...