24 results on '"Rangaraj Selvarangan"'
Search Results
2. Emergence of Parechovirus A3 as the Leading Cause of Central Nervous System Infection, Surpassing Any Single Enterovirus Type, in Children in Kansas City, Missouri, USA, from 2007 to 2016
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Christopher J. Harrison, Dithi Banerjee, Rangaraj Selvarangan, and Anjana Sasidharan
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Microbiology (medical) ,medicine.medical_specialty ,Picornavirus ,Routine testing ,Epidemiology ,Parechovirus ,medicine.disease_cause ,03 medical and health sciences ,0302 clinical medicine ,Central Nervous System Infections ,030225 pediatrics ,medicine ,Enterovirus Infections ,Humans ,030212 general & internal medicine ,Child ,Enterovirus ,Missouri ,Picornaviridae Infections ,biology ,Molecular epidemiology ,business.industry ,fungi ,Infant ,Kansas ,biology.organism_classification ,Virology ,business - Abstract
Picornaviruses, including Enterovirus species A to D (EV) and Parechovirus species A (PeV-A), are the leading reported causes of pediatric central nervous system infections in the United States. We investigated the molecular epidemiology of EV and PeV-A over 10 years in cerebrospinal fluid (CSF) collected from children seen at Children’s Mercy-Kansas City (CMKC) from 2007 through 2016. The overall prevalence for EV was 16% (862/5,362) and 7% (271/4,016) for PeV. Among all picornavirus CSF detections, EV was 76%, and PeV-A was 24%. Multiple EV types cocirculated each year, with a total of 31 EV types detected in the 10-year period; the majority belonged to EV-B species (96%). Two PeV-A types were detected; PeV-A3 was the dominant PeV-A type (95%). The top five picornaviruses (PeV-A3, 26%; E30, 11%; E6, 10%; E18, 9%; E9, 7%) in the CSF of infants accounted for two-thirds of all detections, and PeV-A3 was the leading picornavirus detected. Routine testing and reporting of PeV-A in addition to EV, especially in children under 6 months old with acute febrile illnesses, could reduce hospital stays and antibiotic usage.
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- 2020
3. Molecular Characterization of Mycoplasma pneumoniae Isolates in the United States from 2012 to 2018
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Thomas Prescott Atkinson, Rangaraj Selvarangan, Karen B. Fowler, M. Prichard, Donna M. Crabb, Steven D. Dallas, Y-W Tang, Li Xiao, Lynn B. Duffy, Emily Mixon, Edward G. Brooks, Tao Hong, Xiaotian Zheng, J. Dien Bard, Xuan Qin, Ken B. Waites, and Amy E. Ratliff
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0301 basic medicine ,Microbiology (medical) ,Mycoplasma pneumoniae ,Genotype ,030106 microbiology ,Antimicrobial susceptibility ,Multiple Loci VNTR Analysis ,Biology ,medicine.disease_cause ,03 medical and health sciences ,0302 clinical medicine ,Tandem repeat ,Drug Resistance, Bacterial ,Pneumonia, Mycoplasma ,medicine ,Humans ,030212 general & internal medicine ,Virology ,United States ,Subtyping ,Anti-Bacterial Agents ,Macrolide resistance ,Geographic regions ,Macrolides - Abstract
Mycoplasma pneumoniae is a major cause of community-acquired pneumonia. There are limited data in the United States on the molecular epidemiological characteristics of M. pneumoniae We collected 446 M. pneumoniae-positive specimens from 9 states between August 2012 and October 2018. Culture, antimicrobial susceptibility testing, P1 subtyping, and multilocus VNTR (variable-number tandem repeats) analysis (MLVA) were performed to characterize the isolates. Macrolide-resistant M. pneumoniae (MRMp) was detected in 37 (8.3%) specimens. P1 subtype 2 (P1-2) was the predominant P1 subtype (59.8%). P1 subtype distribution did not change significantly chronologically or geographically. The macrolide resistance rate in P1 subtype 1 (P1-1) samples was significantly higher than that in P1-2 (12.9% versus 5.5%). Six P1-2 variants were identified, including two novel types, and variant 2c was predominant (64.6%). P1-2 variants were distributed significantly differently among geographic regions. Classical P1-2 was more frequent in lower respiratory tract specimens and had longer p1 trinucleotide repeats. Classical P1-2 was most common in MRMp (35.7%), while variant 2c was most common in macrolide-susceptible M. pneumoniae (67.5%). Fifteen MLVA types were identified; 3-5-6-2 (41.7%), 4-5-7-2 (35.3%), and 3-6-6-2 (16.6%) were the major types, and four MLVA clusters were delineated. The distribution of MLVA types varied significantly over time and geographic location. The predominant MLVA type switched from 4-5-7-2 to 3-5-6-2 in 2015. MLVA type was associated with P1 subtypes and P1-2 variant types but not with macrolide resistance. To investigate the M. pneumoniae genotype shift and its impact on clinical presentations, additional surveillance programs targeting more diverse populations and prolonged sampling times are required.
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- 2020
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4. Multicenter Clinical Evaluation of the Revogene Strep A Molecular Assay for Detection of Streptococcus pyogenes from Throat Swab Specimens
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Bryan H. Schmitt, P. Lachance, Matthew L. Faron, Nathan A. Ledeboer, Jeff Michael, Rangaraj Selvarangan, Hossein Salimnia, Dithi Banerjee, Alice S. Weissfeld, N. Mhaissen, T. Aufderheide, and D. M. Goldfarb
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Adult ,0301 basic medicine ,Microbiology (medical) ,Canada ,medicine.medical_specialty ,Microbiological culture ,Streptococcus pyogenes ,030106 microbiology ,multicenter ,medicine.disease_cause ,Sensitivity and Specificity ,Gastroenterology ,03 medical and health sciences ,0302 clinical medicine ,stomatognathic system ,Streptococcal Infections ,030225 pediatrics ,Internal medicine ,medicine ,Humans ,Prospective Studies ,Child ,Prospective cohort study ,molecular assay ,Streptococcus ,business.industry ,group A streptococcus ,Quebec ,Pharyngitis ,Bacteriology ,clinical trial ,Assay sensitivity ,Throat swab ,Confidence interval ,Pharynx ,Sample collection ,business - Abstract
Group A streptococcus (GAS) species cause bacterial pharyngitis in both adults and children. Early and accurate diagnosis of GAS is important for appropriate antibiotic therapy to prevent GAS sequalae. The Revogene Strep A molecular assay (Meridian Bioscience Canada Inc, Quebec City, QC, Canada) is an automated real-time PCR assay for GAS detection from throat swab specimens within approximately 70 min. This multicenter prospective study evaluated the performance of the Revogene Strep A molecular assay compared to that of bacterial culture., Group A streptococcus (GAS) species cause bacterial pharyngitis in both adults and children. Early and accurate diagnosis of GAS is important for appropriate antibiotic therapy to prevent GAS sequalae. The Revogene Strep A molecular assay (Meridian Bioscience Canada Inc, Quebec City, QC, Canada) is an automated real-time PCR assay for GAS detection from throat swab specimens within approximately 70 min. This multicenter prospective study evaluated the performance of the Revogene Strep A molecular assay compared to that of bacterial culture. Dual throat swab specimens in either liquid Amies or Stuart medium were collected from eligible subjects (pediatric population and adults) enrolled across 7 sites (USA and Canada). Revogene Strep A and reference testing was performed within 7 days and 48 h of sample collection, respectively. Of the 604 evaluable specimens, GAS was detected in 154 (25.5%) samples by the reference method and in 175 (29%) samples by the Revogene Strep A assay. Revogene Strep A assay sensitivity and specificity were reported to be 98.1% (95% confidence interval [CI], 94.4 to 99.3) and 94.7% (95% CI, 92.2 to 96.4), respectively. The positive predictive value was 86.3% (95% CI, 80.4 to 90.6), negative predictive value was 99.3% (95% CI, 98.0 to 99.8) with a 1.0% invalid rate. Discrepant analysis with alternative PCR/bidirectional sequencing was performed for 24 false-positive (FP) and 3 false-negative (FN) specimens. Concordant results were reported for 17 (FP only) of 27 discordant specimens. The Revogene Strep A assay had high sensitivity and specificity for GAS detection and provides a faster alternative for GAS diagnosis.
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- 2020
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5. Evaluation of Commercial Molecular Diagnostic Methods for Detection and Determination of Macrolide Resistance in Mycoplasma pneumoniae
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Alvaro J. Benitez, Tao Hong, Sixto M. Leal, Li Xiao, Edward G. Brooks, Steve Dallas, Amy E. Ratliff, Jonas M. Winchell, T. Prescott Atkinson, Karen B. Fowler, Emily Mixon, Ken B. Waites, Jennifer Dien Bard, Xiaotian Zheng, Donna M. Crabb, Bernard J. Wolff, Y-W Tang, Rangaraj Selvarangan, Arthur H. Totten, Xuan Qin, Mark D. Gonzalez, Lynn B. Duffy, and Maureen H. Diaz
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Microbiology (medical) ,Mycoplasma pneumoniae ,business.industry ,Significant difference ,Molecular Diagnostic Method ,Respiratory Pathogen Panel ,Bacteriology ,Mycoplasma ,medicine.disease_cause ,medicine.disease ,Disease control ,Microbiology ,Anti-Bacterial Agents ,Macrolide resistance ,Community-acquired pneumonia ,Drug Resistance, Bacterial ,Pneumonia, Mycoplasma ,Medicine ,Humans ,Macrolides ,Pathology, Molecular ,business - Abstract
We evaluated six commercial molecular tests targeting Mycoplasma pneumoniae, namely, the BioFire FilmArray respiratory panel (RP), the Meridian Alethia Mycoplasma Direct, the GenMark ePlex respiratory pathogen panel (RPP), the Luminex NxTAG RPP, the ELITech ELITe InGenius Mycoplasma MGB research use only (RUO) PCR, and the SpeeDx Resistance Plus MP assays. Laboratory-developed PCR assays at the University of Alabama at Birmingham and the Centers for Disease Control and Prevention were used as reference standards. Among 428 specimens, 212 were designated confirmed positives for M. pneumoniae. The highest clinical sensitivities were found with the InGenius PCR (99.5%) and the FilmArray RP (98.1%). The Resistance Plus MP identified 93.3% of the confirmed-positive specimens, whereas 83.6, 64.6, and 55.7% were identified by the ePlex RPP, NxTAG RPP, and Mycoplasma Direct assays, respectively. There was no significant difference between the sensitivity of the reference methods and that of the FilmArray RP and InGenius assays, but the remaining four assays detected significantly fewer positive specimens (P
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- 2020
6. Comparison of the ID Now Influenza AB 2, Cobas Influenza A/B, and Xpert Xpress Flu Point-of-Care Nucleic Acid Amplification Tests for Influenza A/B Virus Detection in Children
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Jeffrey Michael, Kathryn Doran, Rangaraj Selvarangan, Neena Kanwar, and Emily J Montgomery
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Microbiology (medical) ,Male ,Adolescent ,Real-Time Polymerase Chain Reaction ,Sensitivity and Specificity ,Virus ,influenza detection ,children ,Nasopharynx ,Virology ,Influenza, Human ,Infection control ,Medicine ,Nucleic Acid Amplification Tests ,Humans ,Child ,Point of care ,medicine.diagnostic_test ,business.industry ,Infant, Newborn ,Nucleic acid test ,virus diseases ,Infant ,Influenza a ,Patient management ,Virus detection ,respiratory tract diseases ,Influenza B virus ,Early Diagnosis ,Influenza A virus ,Point-of-Care Testing ,Child, Preschool ,molecular diagnostic assays performance ,Female ,business ,Nucleic Acid Amplification Techniques - Abstract
Early diagnosis of influenza (Flu) is critical for patient management and infection control. The ID Now influenza A & B 2 (ID Now) assay (Abbott Laboratories), Cobas influenza A/B nucleic acid test (LIAT; Roche Molecular Systems, Inc.), and Xpert Xpress Flu (Xpert; Cepheid) are rapid, point-of-care molecular assays for Flu virus detection. The study aim was to compare the performances of these three commercially available Clinical Laboratory Improvement Amendments (CLIA)-waived Flu virus assays., Early diagnosis of influenza (Flu) is critical for patient management and infection control. The ID Now influenza A & B 2 (ID Now) assay (Abbott Laboratories), Cobas influenza A/B nucleic acid test (LIAT; Roche Molecular Systems, Inc.), and Xpert Xpress Flu (Xpert; Cepheid) are rapid, point-of-care molecular assays for Flu virus detection. The study aim was to compare the performances of these three commercially available Clinical Laboratory Improvement Amendments (CLIA)-waived Flu virus assays. We prospectively enrolled 201 children 97%. These molecular assays had higher sensitivity than did a historical standard-of-care test from the BD Veritor antigen test (Flu A virus, 79.5%; Flu B virus, 66.7%).
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- 2019
7. Macrolide-Resistant Mycoplasma pneumoniae in the United States as Determined from a National Surveillance Program
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Steven D. Dallas, Emily Mixon, Thomas Prescott Atkinson, Karen B. Fowler, Edward G. Brooks, Yi-Wei Tang, Lynn B. Duffy, Xiaotian Zheng, M. Prichard, Rangaraj Selvarangan, Li Xiao, Donna M. Crabb, Tao Hong, J. Dien Bard, Xuan Qin, Ken B. Waites, and Amy E. Ratliff
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0301 basic medicine ,Microbiology (medical) ,Adult ,Male ,medicine.medical_specialty ,Mycoplasma pneumoniae ,Adolescent ,Epidemiology ,030106 microbiology ,Microbial Sensitivity Tests ,medicine.disease_cause ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Antibiotic resistance ,23S ribosomal RNA ,Internal medicine ,Drug Resistance, Bacterial ,Pneumonia, Mycoplasma ,Prevalence ,Medicine ,Humans ,Clinical significance ,030212 general & internal medicine ,Child ,Immunodeficiency ,Aged ,Aged, 80 and over ,business.industry ,Incidence (epidemiology) ,Macrolide resistant ,Infant ,Middle Aged ,medicine.disease ,United States ,Anti-Bacterial Agents ,RNA, Ribosomal, 23S ,Macrolide resistance ,Child, Preschool ,Epidemiological Monitoring ,Mutation ,Female ,Macrolides ,business - Abstract
There are sparse data to indicate the extent that macrolide-resistant Mycoplasma pneumoniae (MRMp) occurs in the United States or its clinical significance. Between 2015 and 2018, hospitals in 8 states collected and stored respiratory specimens that tested positive for M. pneumoniae and sent them to the University of Alabama at Birmingham, where real-time PCR was performed for detection of 23S rRNA mutations known to confer macrolide resistance. MRMp was detected in 27 of 360 specimens (7.5%). MRMp prevalence was significantly higher in the South and East (18.3%) than in the West (2.1%). A2063G was the predominant 23S rRNA mutation detected. MICs for macrolide-susceptible M. pneumoniae (MSMp) were ≤0.008 μg/ml, whereas MICs for MRMp were 16 to 32 μg/ml. Patients with MRMp infection were more likely to have a history of immunodeficiency or malignancy. Otherwise, there were no other significant differences in the clinical features between patients infected with MRMp and those infected with MSMp, nor were there any differences in radiographic findings, hospitalization rates, viral coinfections, the mean duration of antimicrobial treatment, or clinical outcomes. There was no significant change in MRMp incidence over time or according to age, sex, race/ethnicity, or status as an inpatient or an outpatient. Patients with MRMp were more likely to have received a macrolide prior to presentation, and their treatment was more likely to have been changed to a fluoroquinolone after presentation. This is the first national surveillance program for M. pneumoniae in the United States. Additional surveillance is needed to assess the clinical significance of MRMp and to monitor changes in MRMp prevalence.
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- 2019
8. Emergence of Parechovirus A4 Central Nervous System Infections among Infants in Kansas City, Missouri, USA
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Christopher J. Harrison, Rangaraj Selvarangan, Anjana Sasidharan, and Dithi Banerjee
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0301 basic medicine ,Microbiology (medical) ,medicine.medical_specialty ,Fever ,Genotype ,Lymphocyte ,030106 microbiology ,Central nervous system ,Parechovirus ,Communicable Diseases, Emerging ,03 medical and health sciences ,0302 clinical medicine ,Cerebrospinal fluid ,Virology ,White blood cell ,Internal medicine ,medicine ,Humans ,030212 general & internal medicine ,Genotyping ,Phylogeny ,Maximum temperature ,Missouri ,Picornaviridae Infections ,biology ,business.industry ,fungi ,Infant, Newborn ,Infant ,Sequence Analysis, DNA ,biology.organism_classification ,medicine.anatomical_structure ,Central Nervous System Viral Diseases ,Seasons ,business - Abstract
Among known parechovirus (PeV) types infecting humans, PeV-A3 (formerly HPeV3) and PeV-A1 (formerly HPeV1) are associated with pediatric central nervous system (CNS) infections. The prevalence of PeV-A3 among hospitalized infants with sepsis-like illness and viral CNS infection is well described; however, the contribution of PeV-A4 to infant CNS infection is relatively unexplored. We report the first 11 U.S. cases of PeV-A4 CNS infections occurring in Kansas City infants during 2010 to 2016 and compare the clinical presentation with that of PeV-A3. PeV-positive cerebrospinal fluid (CSF) specimens from 2010 to 2016 underwent sequencing for genotyping. Among all PeV-CSF positives, PeV-A4 was detected in 11 CSF samples from 2010 to 2016. PeV-A4 was first detected in 2010 (n = 1/4), followed by detections in 2014 (n = 1/39), 2015 (n = 6/9), and 2016 (n = 3/33). The median age of PeV-A4-infected infants in weeks (median, 4; range, 1 to 8) was similar to that of infants infected with PeV-A3 (median, 4; range, 0.25 to 8). Clinical characteristics of PeV-A4 (n = 11) were compared with those of select PeV-A3-infected children (n = 34) with CNS infections and found to be mostly similar, although maximum temperature was higher (P = 0.017) and fever duration was shorter (P = 0.03) for PeV-A4 than for PeV-A3. Laboratory test results were also similar between genotypes, although they showed significantly lower peripheral white blood cell (P = 0.014) and absolute lymphocyte (P = 0.04) counts for PeV-A4 infants. Like PeV-A3, PeV-A4 caused summer-fall seasonal clusters of CNS infections in infants, with mostly similar presentations. Further surveillance is necessary to confirm potential differences in laboratory findings and in fever intensity/duration.
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- 2019
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9. Evaluation of BacterioScan 216Dx in Comparison to Urinalysis as a Screening Tool for Diagnosis of Urinary Tract Infections in Children
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Megan Gripka, Heather Bushnell, Ferdaus Hassan, Ashley Formanek, Caitlin Gibbs, Steve Hiraki, Connie Taggart, and Rangaraj Selvarangan
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Microbiology (medical) ,Male ,medicine.medical_specialty ,Time Factors ,Urinalysis ,Adolescent ,Urinary system ,Urine ,Sensitivity and Specificity ,03 medical and health sciences ,0302 clinical medicine ,Predictive Value of Tests ,030225 pediatrics ,Internal medicine ,Medicine ,Humans ,Mass Screening ,Screening tool ,030212 general & internal medicine ,Child ,Automation, Laboratory ,Bacteriological Techniques ,medicine.diagnostic_test ,business.industry ,Diagnostic Tests, Routine ,Infant, Newborn ,Infant ,Bacteriology ,Child, Preschool ,Urinary Tract Infections ,Female ,business - Abstract
Urinalysis (UA) has routinely been used as a screening tool prior to urine culture set up. BacterioScan 216Dx is an FDA-cleared semiautomated system to detect bacterial growth in urine. The aim of this study was to evaluate 216Dx in comparison to UA for diagnosis of urinary tract infection (UTI) in children. Clean-catch, unpreserved urine samples from children aged
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- 2019
10. Multicenter Clinical Evaluation of the Automated Aries Group A Strep PCR Assay from Throat Swabs
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Neena Kanwar, Ronald Dunn, C. Ulen, Timothy S. Uphoff, Jordan Crawford, A. Drain, Rangaraj Selvarangan, and J. Dien Bard
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Adult ,Male ,0301 basic medicine ,Microbiology (medical) ,medicine.medical_specialty ,Time Factors ,Adolescent ,Streptococcus pyogenes ,030106 microbiology ,medicine.disease_cause ,Polymerase Chain Reaction ,Sensitivity and Specificity ,Gastroenterology ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Streptococcal Infections ,Throat ,Internal medicine ,medicine ,Humans ,Prospective Studies ,030212 general & internal medicine ,Child ,Prospective cohort study ,Aged ,Aged, 80 and over ,Automation, Laboratory ,Streptococcus ,business.industry ,Infant ,Bacteriology ,Assay sensitivity ,Middle Aged ,United States ,Confidence interval ,Pharyngitis ,respiratory tract diseases ,medicine.anatomical_structure ,Molecular Diagnostic Techniques ,Child, Preschool ,Pharynx ,Female ,Sample collection ,medicine.symptom ,business - Abstract
Group A Streptococcus (GAS) is one of the leading causes of bacterial pharyngitis. Early GAS diagnosis is critical for appropriate antibiotic administration that reduces the risk of GAS sequelae and limits spread of the infection. The Aries Group A Strep (GAS) assay (Luminex, Austin, TX) is a fully automated PCR assay for direct detection of GAS in throat swab specimens in less than 2 h with minimum hands-on time. This multicenter prospective study evaluated the clinical performance of the Aries GAS assay compared to that of Streptococcus pyogenes culture. Subjects with symptoms consistent with pharyngitis were enrolled across four sites in the United States, and a throat swab in liquid Amies medium was obtained. Aries and reference testing was performed within 72 and 48 h after sample collection, respectively. Of 623 throat swab specimens from patients with pharyngitis (93.6%
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- 2019
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11. Comparison of Six Sample-to-Answer Influenza A/B and Respiratory Syncytial Virus Nucleic Acid Amplification Assays Using Respiratory Specimens from Children
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Dithi Banerjee, Neena Kanwar, Ferdaus Hassan, Cynthia Essmyer, and Rangaraj Selvarangan
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0301 basic medicine ,Microbiology (medical) ,030106 microbiology ,Respiratory Syncytial Virus Infections ,Biology ,medicine.disease_cause ,Sensitivity and Specificity ,Virus ,03 medical and health sciences ,Nasopharynx ,Virology ,parasitic diseases ,Influenza, Human ,Influenza A virus ,medicine ,Humans ,Respiratory system ,Child ,Retrospective Studies ,GeneXpert MTB/RIF ,virus diseases ,Infant ,Influenza a ,bacterial infections and mycoses ,Disease control ,Subtyping ,Influenza B virus ,Child, Preschool ,Respiratory Syncytial Virus, Human ,Nucleic acid ,Nucleic Acid Amplification Techniques - Abstract
The rapid and accurate detection of influenza A virus (FluA), influenza B virus (FluB), and respiratory syncytial virus (RSV) improves patient care. Sample-to-answer (STA) platforms based on nucleic acid amplification and detection of these viruses are simple, automated, and accurate. We compared six such platforms for the detection of FluA, FluB, and RSV: Cepheid GeneXpert Xpress Flu/RSV (Xpert), Hologic Panther Fusion Flu A/B/RSV (Fusion), Cobas influenza A/B & RSV (Liat), Luminex Aries Flu A/B & RSV (Aries), BioFire FilmArray respiratory panel (RP), and Diasorin Simplexa Flu A/B & RSV (Simplexa). Nasopharyngeal (NP) swab specimens (n = 225) from children previously tested by RP were assessed on these platforms. The results were compared to those of the Centers for Disease Control and Prevention (CDC)-developed real-time reverse transcription-PCR (rRT-PCR) assay for influenza A/B viruses and RSV. Subtyping for FluA and FluB was performed for discrepant analysis where applicable. The percent sensitivities/specificities for FluA detection were 100/100 (Fusion), 98.6/99.3 (Xpert), 100/100 (Liat), 98.6/100 (Aries), 98.6/100 (Simplexa), and 100/100 (RP). The percent sensitivities/specificities for FluB detection were 100/100 (Fusion), 97.9/99.4 (Xpert), 97.9/98.3 (Liat), 93.7/99.4 (Aries), 85.4/99.4 (Simplexa), and 95.8/97.7 (RP); and those for RSV detection were 98.1/99.4 (Xpert), 98.1/99.4 (Liat), 96.3/100 (Fusion), 94.4/100 (Aries), 87/94.4 (Simplexa), and 94.4/100 (RP). The 75 strains confirmed to be FluA included 29 pH1N1, 39 H3N2, 4 sH1N1, and 3 untyped strains. The 48 strains confirmed to be FluB included 33 strains of the Yamagata lineage, 13 of the Victoria lineage, 1 of both the Yamagata and Victoria lineages, and 1 of an unknown lineage. All six STA platforms demonstrated >95% sensitivity for FluA detection, while three platforms (Fusion, Xpert, and Liat) demonstrated >95% sensitivity for FluB and RSV detection.
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- 2018
12. Evaluation of the illumigene Mycoplasma Direct DNA Amplification Assay
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Donna Mayne, Rangaraj Selvarangan, Jeffrey Michael, Morgan A. Pence, and Neena Kanwar
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0301 basic medicine ,Microbiology (medical) ,Adult ,Male ,Mycoplasma pneumoniae ,In vitro test ,Adolescent ,030106 microbiology ,Loop-mediated isothermal amplification ,medicine.disease_cause ,Sensitivity and Specificity ,Microbiology ,03 medical and health sciences ,Young Adult ,Throat ,Pneumonia, Mycoplasma ,illumigene assay ,medicine ,Humans ,Prospective Studies ,Child ,Respiratory Tract Infections ,Aged ,Aged, 80 and over ,business.industry ,Diagnostic Tests, Routine ,LAMP technology ,Infant, Newborn ,Infant ,Bacteriology ,Mycoplasma ,Middle Aged ,Dna amplification ,DNA extraction ,United States ,medicine.anatomical_structure ,Multicenter study ,Molecular Diagnostic Techniques ,Child, Preschool ,Pharynx ,Female ,business ,Nucleic Acid Amplification Techniques - Abstract
Mycoplasma pneumoniae is a common cause of community-acquired pneumonia. The illumigene Mycoplasma Direct (iMD) DNA amplification assay is a qualitative in vitro test utilizing loop-mediated isothermal amplification (LAMP) technology for the direct detection of M. pneumoniae DNA in respiratory specimens. The iMD assay does not require the preextraction of nucleic acids from specimens, which is a prerequisite step for the previously approved illumigene Mycoplasma (iM) assay. The aim of this prospective multicenter study was to evaluate the performance characteristics of the newly developed iMD assay, compared with the iM assay. Subjects with symptoms of upper respiratory illnesses suggesting M. pneumoniae infection were enrolled at three sites in the United States. Respiratory specimens were obtained using dual throat swabs. One swab was tested with the iMD assay at each enrollment site. Reference testing with the iM assay was performed by the manufacturer. Among 456 specimens tested, the iM reference method detected M. pneumoniae in 25 specimens (5.5%), while the iMD assay identified 34 specimens (7.5%) as M. pneumoniae positive. There were 10 false-positive results and 1 false-negative result with the iMD assay. The overall positive and negative agreement rates were 96.0% (95% confidence interval [CI], 80.5 to 99.3%) and 97.7% (95% CI, 95.8 to 98.7%), respectively. The overall agreement rate was determined to be 97.6% (95% CI, 95.7 to 98.6%). We conclude that the iMD test results were comparable to the iM assay results. The removal of the DNA extraction step for the iMD assay simplifies testing, saves time, and reduces the costs of detecting M. pneumoniae from throat swabs, compared to the iM assay.
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- 2017
13. Evaluation of the Alere i Influenza A&B Nucleic Acid Amplification Test by Use of Respiratory Specimens Collected in Viral Transport Medium
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Jeremiah Bell and Rangaraj Selvarangan
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Male ,Microbiology (medical) ,Virus Cultivation ,Adolescent ,Biology ,medicine.disease_cause ,Sensitivity and Specificity ,Virus ,Specimen Handling ,Young Adult ,Virology ,Influenza, Human ,Influenza A virus ,medicine ,Humans ,Respiratory system ,Child ,Viral culture ,virus diseases ,Infant ,Nucleic acid amplification technique ,Influenza B virus ,Molecular Diagnostic Techniques ,Cell culture ,Child, Preschool ,Nucleic acid ,Female ,Sample collection ,Nucleic Acid Amplification Techniques - Abstract
The Alere i Influenza A&B assay is a newly developed rapid molecular assay which has the potential to generate results within 15 min from sample collection. In this study, we evaluated the Alere i Influenza A&B assay by using salvaged frozen respiratory specimens that were collected in viral transport medium from children ages 10 months to 19 years. Alere i Influenza A&B assay test results were compared with viral culture and ProFlu + real-time reverse transcription-PCR (RT-PCR) assay results. We found that the overall sensitivity and specificity of the Alere i Influenza A&B assay were 93.3% and 94.5% for the detection of influenza A virus and 100% and 100% for the detection of influenza B virus, respectively, compared to viral culture. In comparison to ProFlu + real-time RT-PCR, overall sensitivity and specificity of the Alere i Influenza A&B assay for the detection of influenza A virus were 88.8% and 98.3% and 100% and 100% for detecting influenza B virus. Overall, the Alere i Influenza A&B assay performed well compared to either virus cell culture or RT-PCR.
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- 2014
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14. Evaluation of Three Influenza A and B Real-Time Reverse Transcription-PCR Assays and a New 2009 H1N1 Assay for Detection of Influenza Viruses
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Suresh B. Selvaraju and Rangaraj Selvarangan
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Microbiology (medical) ,Reverse Transcriptase Polymerase Chain Reaction ,viruses ,Orthomyxoviridae ,virus diseases ,Influenza a ,Biology ,medicine.disease_cause ,biology.organism_classification ,Sensitivity and Specificity ,Virology ,Virus ,Seasonal influenza ,Reverse transcription polymerase chain reaction ,Influenza B virus ,Influenza A virus ,Influenza, Human ,medicine ,Humans ,Multiplex ,Reagent Kits, Diagnostic ,Viral disease - Abstract
The performance characteristics of three real-time influenza A/B virus reverse transcription-PCR (RT-PCR) assays and two real-time 2009 H1N1 RT-PCR assays were evaluated using previously characterized clinical specimens. A total of 150 respiratory specimens from children (30 influenza A/H1 virus-, 30 influenza A/H3 virus-, 30 2009 H1N1-, and 30 influenza B virus-positive specimens and 30 influenza virus-negative specimens) were tested with the CDC influenza A/B PCR (CDC), ProFlu + multiplex real-time RT-PCR assay (ProFlu + ), and MGB Alert Influenza A/B & RSV RUO (MGB) assays. A second set of 157 respiratory specimens (100 2009 H1N1-, 22 seasonal influenza A/H1-, and 15 seasonal influenza A/H3-positive specimens and 20 influenza-negative specimens) were tested with a new laboratory-developed 2009 H1N1 RT-PCR and the CDC 2009 H1N1 assay. The overall sensitivities of the CDC, ProFlu + , and MGB assays for detection of influenza A and B viruses were 100%, 98.3%, and 94%, respectively. The ProFlu + assay failed to detect one influenza A/H1 virus-positive specimen and yielded one unresolved result with another influenza A/H1 virus-positive specimen. The MGB assay detected 84/87 (96.5%) of influenza A and B viruses and 26/30 (86.6%) of 2009 H1N1 viruses. The new laboratory-developed 2009 H1N1 RT-PCR assay detected 100/100 (100%) 2009 H1N1 virus-positive specimens, while the CDC SW Inf A and SW H1 PCR assays failed to detect one and three low-positive 2009 H1N1-positive specimens, respectively. The CDC influenza A/B virus assay and the newly developed 2009 H1N1 RT-PCR assay with an internal control can be set up in two separate reactions in the same assay for routine clinical testing to detect influenza A and B viruses and to specifically identify the 2009 H1N1 influenza virus.
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- 2010
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15. Comparison of Molecular Characteristics of Mycoplasma pneumoniae Specimens Collected from the United States and China
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Xiaotian Zheng, Chao Yan, Yi-Wei Tang, Ken B. Waites, Stella Lee, Xuan Qin, Hongmei Sun, and Rangaraj Selvarangan
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Microbiology (medical) ,Adult ,Mycoplasma pneumoniae ,China ,Genotype ,Epidemiology ,Biology ,medicine.disease_cause ,Microbiology ,Drug Resistance, Bacterial ,Pneumonia, Mycoplasma ,medicine ,Prevalence ,Humans ,Child ,Infant, Newborn ,Genetic Variation ,Infant ,Mycoplasma ,Infant newborn ,United States ,Anti-Bacterial Agents ,Macrolide resistance ,Child, Preschool ,Lower prevalence ,Macrolides - Abstract
Mycoplasma pneumoniae -positive clinical specimens obtained from the United States and China during the same period were studied for their molecular characteristics. We found much more diverse genotypes and a lower prevalence of macrolide resistance in the U.S. specimens. Data from the study also showed an association of the resistance with certain genotypes.
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- 2015
16. Reply to 'new rapid diagnostic tests: a real improvement for clinical use?'
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Rangaraj Selvarangan and Ferdaus Hassan
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Microbiology (medical) ,Male ,medicine.medical_specialty ,Bodily Secretions ,business.industry ,Diagnostic Tests, Routine ,Respiratory System ,MEDLINE ,Diagnostic test ,Influenza a ,medicine.disease_cause ,Influenza B virus ,Influenza A virus ,Virology ,Immunology ,Influenza, Human ,medicine ,Humans ,In patient ,Female ,Intensive care medicine ,business ,Letters to the Editor ,Bodily secretions - Abstract
In the letter [“New rapid diagnostic tests: a real improvement for clinical use?”][1] by Fernandez-Santos et al. ([1][2]), concern is raised regarding use of rapid influenza detection tests (RIDTs) for detection of influenza A and B viruses in patients due to their varied sensitivities. A
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- 2015
17. Characterization of a Novel Group of Mycobacteria and Proposal of Mycobacterium sherrisii sp. nov
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Trang Nguyen, Rangaraj Selvarangan, Richard J. Wallace, La Donna C. Carlson, Brad T. Cookson, Sara L. Rassoulian Barrett, Yi-Ching Chen, Kenneth C. Jost, Jennifer L. Prentice, Whei Kuo Wu, Carolyn K. Wallis, Susan K. Stiglich, and Marie B. Coyle
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DNA, Bacterial ,Microbiology (medical) ,Chromatography, Gas ,Base Sequence ,Genotype ,Sequence analysis ,Fatty Acids ,Molecular Sequence Data ,Mycobacteriology and Aerobic Actinomycetes ,Ribosomal RNA ,Biology ,biology.organism_classification ,16S ribosomal RNA ,Mycobacterium ,Microbiology ,chemistry.chemical_compound ,genomic DNA ,Phenotype ,chemistry ,Gene ,Chromatography, High Pressure Liquid ,Phylogeny ,DNA - Abstract
We describe here the characterization of five isolates of Mycobacterium simiae -like organisms representing a novel group based on whole-cell fatty acid analysis and genotypic evaluation. Two of the five isolates in this study, W55 and W58, were previously considered to belong to M. simiae serotype 2. Analysis of cellular fatty acids by gas-liquid chromatography indicated a close clustering of this group, which was well differentiated from the other M. simiae -like species. Molecular characterization was performed by nucleic acid sequencing of the small subunit rRNA gene and the gene encoding the 65-kDa heat shock protein and genomic DNA hybridization. Sequence analysis of the entire 16S rRNA gene showed a unique sequence most closely related to those of M. triplex and M. simiae . The hsp65 partial gene sequence was identical for the five isolates, with 97% identity to the M. simiae type strain. However, qualitative whole genomic DNA hybridization analysis confirmed that this group is genetically distinct from M. simiae and M. triplex . Antimicrobial susceptibilities for this group resemble those of M. simiae and M. lentiflavum . We conclude that this group represents a unique Mycobacterium species for which we propose the name Mycobacterium sherrisii sp. nov.
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- 2004
- Full Text
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18. Rapid Identification of Commonly Encountered Candida Species Directly from Blood Culture Bottles
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Uyen Bui, Rangaraj Selvarangan, Brad T. Cookson, and Ajit P. Limaye
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Microbiology (medical) ,Candida glabrata ,Mycology ,Polymerase Chain Reaction ,Microbiology ,law.invention ,law ,Candida albicans ,medicine ,Humans ,Blood culture ,Internal transcribed spacer ,DNA, Fungal ,Polymerase chain reaction ,Candida ,DNA Primers ,Base Sequence ,biology ,medicine.diagnostic_test ,Hybridization probe ,Gene Amplification ,biology.organism_classification ,Molecular biology ,Corpus albicans ,Culture Media ,RRNA Operon ,Oligonucleotide Probes ,Algorithms - Abstract
We report a rapid-cycle, real-time PCR method for identifying six Candida spp. directly from BACTEC blood culture bottles. Target sequences in the noncoding internal transcribed spacer regions of the rRNA operon were simultaneously amplified and interrogated with fluorescent probes to identify Candida albicans , C. glabrata , C. parapsilosis , C. tropicalis , C. krusei , and C. lusitaniae ; these account for 88% of the yeast species isolated from positive blood cultures in our laboratory. Any of the first four species can be identified in a single reaction using two fluorescent hybridization probe sets. The antifungal-resistant species C. krusei and C. lusitaniae are detected in a second reaction, also with two probe sets. The assay was validated with DNA extracted from BACTEC blood culture bottles positive for yeasts ( n = 62) and was 100% concordant with culture identification based on biochemical and morphological features of C. albicans ( n = 22), C. parapsilosis ( n = 10), C. tropicalis ( n = 1) C. glabrata ( n = 22), C. krusei ( n = 2), and C. lusitaniae ( n = 1). No cross-reactivity was observed in blood culture samples growing yeasts other than the above-mentioned species ( n = 4), in those growing bacteria ( n = 12), or in the absence of microbial growth. Our assay allows rapid (≤2 h) and specific detection of the most common Candida spp. directly from positive blood cultures and may facilitate delivery of optimal antifungal therapy.
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- 2003
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19. Rapid Receptor-Clustering Assay To Detect Uropathogenic and Diarrheal Escherichia coli Isolates Bearing Adhesins of the Dr Family
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Rangaraj Selvarangan, K. Nguyen, Pawel Goluszko, Bogdan Nowicki, Stella Nowicki, Audrey Hart, and E. Pawelczyk
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Diarrhea ,Microbiology (medical) ,Time Factors ,Receptors, Cell Surface ,medicine.disease_cause ,Microbiology ,Pregnancy ,Escherichia coli ,medicine ,Humans ,Pregnancy Complications, Infectious ,Receptor ,Escherichia coli Infections ,Regulation of gene expression ,Adhesins, Escherichia coli ,CD55 Antigens ,Pyelonephritis ,biology ,Bacteriology ,biology.organism_classification ,Enterobacteriaceae ,Virology ,Bacterial adhesin ,Female ,Receptor clustering ,medicine.symptom ,Bacteria ,HeLa Cells - Abstract
Infections caused by Escherichia coli isolates expressing adhesins of the Dr family are associated with diarrhea and urinary tract infections, and these E. coli strains recognize the complement regulatory protein decay-accelerating factor (DAF) as their receptor. Clustering of the DAF receptor at the sites of bacterial adherence to epithelial cells is proposed as an alternative to PCR assay for rapid detection of Dr-positive E. coli .
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- 2001
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20. Characterization of AfaE Adhesins Produced by Extraintestinal and Intestinal Human Escherichia coli Isolates: PCR Assays for Detection of Afa Adhesins That Do or Do Not Recognize Dr Blood Group Antigens
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Laurence du Merle, Bogdan Nowicki, Saeid Bouzari, Antoine Andremont, Rangaraj Selvarangan, Mabel Jouve, Pierre Gounon, Lila Lalioui, Chantal Le Bouguénec, Pascale Courcoux, Yves Germani, and Marie-Isabelle Garcia
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Adult ,Microbiology (medical) ,Oligonucleotides ,Biology ,medicine.disease_cause ,Polymerase Chain Reaction ,law.invention ,Microbiology ,law ,Pathogenic Escherichia coli ,Operon ,parasitic diseases ,Escherichia coli ,medicine ,Animals ,Humans ,Diffusely Adherent Escherichia coli ,Child ,Gene ,Escherichia coli Infections ,Polymerase chain reaction ,Adhesins, Escherichia coli ,CD55 Antigens ,Infant, Newborn ,Infant ,Bacteriology ,biology.organism_classification ,Enterobacteriaceae ,Subtyping ,Bacterial adhesin ,Intestinal Diseases ,Blood Group Antigens ,HeLa Cells - Abstract
Operons of the afa family are expressed by pathogenic Escherichia coli strains associated with intestinal and extraintestinal infections in humans and animals. The recently demonstrated heterogeneity of these operons (L. Lalioui, M. Jouve, P. Gounon, and C. Le Bouguénec, Infect. Immun. 67:5048–5059, 1999) was used to develop a new PCR assay for detecting all the operons of the afa family with a single genetic tool. This PCR approach was validated by investigating three collections of human E. coli isolates originating from the stools of infants with diarrhea (88 strains), the urine of patients with pyelonephritis (97 strains), and the blood of cancer patients (115 strains). The results obtained with this single test and those previously obtained with several PCR assays were closely correlated. The AfaE adhesins encoded by the afa operons are variable, particularly with respect to the primary sequence encoded by the afaE gene. The receptor binding specificities have not been determined for all of these adhesins; some recognize the Dr blood group antigen (Afa/Dr + adhesins) on the human decay-accelerating factor (DAF) as a receptor, and others (Afa/Dr − adhesins) do not. Thus, the afa operons detected in this study were characterized by subtyping the afaE gene using specific PCRs. In addition, the DAF-binding capacities of as-yet-uncharacterized AfaE adhesins were tested by various cellular approaches. The afaE8 subtype (Afa/Dr − adhesin) was found to predominate in afa -positive isolates from sepsis patients (75%); it was frequent in afa -positive pyelonephritis E. coli (55.5%) and absent from diarrhea-associated strains. In contrast, Afa/Dr + strains (regardless of the afaE subtype) were associated with both diarrhea (100%) and extraintestinal infections (44 and 25% in afa -positive pyelonephritis and sepsis strains, respectively). These data suggest that there is an association between the subtype of AfaE adhesin and the physiological site of the infection caused by afa -positive strains.
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- 2001
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21. Optimization of a combined human parechovirus-enterovirus real-time reverse transcription-PCR assay and evaluation of a new parechovirus 3-specific assay for cerebrospinal fluid specimen testing
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Suresh B. Selvaraju, Rangaraj Selvarangan, W. Allan Nix, and M. Steven Oberste
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Microbiology (medical) ,Picornaviridae Infections ,biology ,Cerebrospinal fluid specimen ,Human parechovirus ,Parechovirus ,Reproducibility of Results ,medicine.disease_cause ,biology.organism_classification ,Real-Time Polymerase Chain Reaction ,Virology ,Sensitivity and Specificity ,Reverse transcription polymerase chain reaction ,Real-time polymerase chain reaction ,medicine ,Enterovirus Infections ,Enterovirus ,Humans ,Parallel detection ,Reagent Kits, Diagnostic ,Parechovirus 3 - Abstract
Human parechoviruses (HPeVs), particularly type 3 (HPeV3), are known central nervous system (CNS) pathogens, causing serious infections in infants similar to those caused by enteroviruses (EVs). The primary aim of this study was to combine and validate HPeV and EV real-time reverse transcription-PCR (RT-PCR) detection assays with the best available RT-PCR reagents and conditions for parallel detection of HPeV and EV on a single platform. The secondary aim was to develop and validate a newly developed HPeV3-specific real-time RT-PCR assay. Five commercially available RT-PCR kits were evaluated with the pan-HPeV and EV assays in one-step and two-step RT-PCRs. Two-step RT-PCR with the AgPath ID RT-PCR (AGP) kit performed best for both pan-HPeV and EV assays. The pan-HPeV-specific assay performed best with the AGP kit in a one-step RT-PCR. Frozen aliquots of 145 (for HPeV, n = 70; for EV, n = 75) previously characterized cerebrospinal fluid (CSF) specimens were tested by EV-, pan-HPeV-, and HPeV3-specific (HPeV specimens only) assays. The pan-HPeV and EV assays demonstrated 100% analytical sensitivity and specificity compared to historic results, while the HPeV3-specific assay demonstrated 97% sensitivity and 100% specificity. We propose a real-time pan-HPeV, EV two-step RT-PCR algorithm for simultaneous detection of HPeV and EV from CSF specimens on a single platform. The HPeV3-specific one-step RT-PCR assay can be used as a rapid and cost-effective assay to detect and identify HPeV3 in pan-HPeV RT-PCR assay-positive CSF specimens.
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- 2012
22. Human parechovirus in respiratory specimens from children in Kansas City, Missouri
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W. Allan Nix, Christopher J. Harrison, M. Steven Oberste, Rangaraj Selvarangan, Jeremiah Bell, and Justin Sharp
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Microbiology (medical) ,Male ,Pediatrics ,medicine.medical_specialty ,Prevalence ,Parechovirus ,Virology ,Medicine ,Humans ,In patient ,Respiratory system ,Respiratory Tract Infections ,Retrospective Studies ,Missouri ,Picornaviridae Infections ,biology ,business.industry ,Human parechovirus ,Recem nascido ,Infant, Newborn ,Infant ,biology.organism_classification ,Child, Preschool ,Female ,business - Abstract
We detected a 3% prevalence rate for human parechovirus (HPeV) in 720 respiratory specimens collected from 637 children seen in our hospital in 2009. Fifteen of 20 were HPeV-3 and two were HPeV-1. Only nonspecific, modest respiratory symptoms were evident in patients with detectable HPeV in respiratory specimens. Seven patients had concurrent respiratory and central nervous system (CNS) HPeV-3 infection, suggesting a possible respiratory route of acquisition.
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- 2012
23. A longitudinal case series description of meningitis due to Streptococcus gallolyticus subsp. pasteurianus in infants
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Denise Bratcher, J. Michael Klatte, Rangaraj Selvarangan, and Jill E. Clarridge
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Microbiology (medical) ,DNA, Bacterial ,Male ,Biology ,DNA, Ribosomal ,Microbiology ,Meningitis, Bacterial ,RNA, Ribosomal, 16S ,Streptococcal Infections ,medicine ,Cluster Analysis ,Humans ,Streptococcus gallolyticus ,Pathogen ,Phylogeny ,Infant, Newborn ,Bacteriology ,Sequence Analysis, DNA ,medicine.disease ,Streptococcus bovis ,biology.organism_classification ,Virology ,Anti-Bacterial Agents ,Streptococcus gallolyticus subsp. pasteurianus ,Bacteremia ,Etiology ,Bacterial meningitis ,Female ,Meningitis - Abstract
Streptococcus gallolyticus subsp. pasteurianus , previously known as Streptococcus bovis biotype II.2, is known to cause multiple infectious complications, including bacterial meningitis, in adults. Only sporadic individual case reports have identified this pathogen as a cause of meningitis in infants. This study is the first to longitudinally document S. gallolyticus subsp. pasteurianus as a cause of meningitis in four epidemiologically unrelated infants less than 2 weeks of age. The 16S rRNA gene sequences of all 4 isolates were identical, and further were identical to 3 central nervous system (CNS) strains (two adults and one child) reported in existing literature. S. gallolyticus subsp. pasteurianus is an increasingly recognized cause of meningitis and bacteremia in the newborn period, and it merits further study with respect to etiology of infection.
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- 2011
24. Rapid identification and differentiation of Candida albicans and Candida dubliniensis by capillary-based amplification and fluorescent probe hybridization
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Rangaraj Selvarangan, Ajit P. Limaye, and Brad T. Cookson
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Microbiology (medical) ,Time Factors ,Mycology ,Polymerase Chain Reaction ,Sensitivity and Specificity ,law.invention ,Candida tropicalis ,chemistry.chemical_compound ,law ,Candida albicans ,DNA, Ribosomal Spacer ,Humans ,DNA, Fungal ,Mycological Typing Techniques ,Polymerase chain reaction ,Candida ,Fluorescent Dyes ,biology ,Hybridization probe ,Candidiasis ,Temperature ,biology.organism_classification ,Molecular biology ,Corpus albicans ,chemistry ,Nucleic acid ,DNA Probes ,DNA ,Candida dubliniensis - Abstract
We developed a rapid genotypic assay to differentiate the germ tube-positive yeasts Candida albicans and Candida dubliniensis . Fluorescently labeled nucleic acid probe binding and subsequent denaturation from the target site in the PCR amplicons produced characteristic peak melting temperatures ( T m ) that identified each species. Peak T m s of C. albicans ( n = 69) and C. dubliniensis ( n = 28) isolates produced in the presence of their respective probes were 61.04 ± 0.64°C and 60.52 ± 1.01°C (averages ± standard deviations). No signal was generated when the C. albicans or C. dubliniensis probes were tested against DNA from their counterparts. Both probes reacted with Candida tropicalis DNA, but the T m was 51.85 ± 0.05°C with the C. albicans probe and 51.92 ± 0.10°C with the C. dubliniensis probe, differentiating C. tropicalis DNA from C. albicans and C. dubliniensis. A novel hybrid probe was designed to identify both species in a single reaction based on a 4°C difference in peak T m s. Our assay is rapid (≤2 h) and allows reliable detection and differentiation of the two germ tube-positive Candida spp.
- Published
- 2002
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