Multiplex PCR assay for detection of Actinobacillus pleuropneumoniae, Pasteurella multocida and Haemophilus parasuis in lungs of pigs from a slaughterhouse

The ability to distinguish among the subspecies of Pasteurella multocida isolates is important epidemiologically; however, classification at the subspecies level based on the results of conventional biochemical tests (fermentation of sorbitol and dulcitol) is reportedly not accurate in all cases. Therefore, we developed a rapid, multiplex PCR assay to differentiate among the 3 subspecies of P. multocida. The PCR assay includes the P. multocida species–specific primers KMT1SP6 and KMT1T7 as an internal amplification control, with a newly designed gatD (galactitol-1-phosphate-5-dehydrogenase)-specific primer pair (unique for subsp. gallicida), and primers targeting a 16S rRNA gene region specific for subsp. septica. The subspecies specificity of the PCR was demonstrated by applying the test to a collection of 70 P. multocida isolates, including the Heddleston serovar reference strains; all isolates and strains were assigned correctly. The PCR assay is a sensitive, specific, and highly effective method for the identification of P. multocida subspecies, and an alternative to biochemical test–based differentiation. A possible relationship was noticed between P. multocida subspecies and lipopolysaccharide (LPS) genotype; all but one of the subsp. gallicida strains were isolated only from avian hosts and represented L1 LPS genotype. Subsp. multocida and subsp. septica isolates were classified into 5 and 4 different LPS genotypes, respectively, of which L3 was the only LPS genotype shared between these 2 subspecies.

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Detection and Identification ofActinobacillus pleuropneumoniae Serotype 5 by Multiplex PCR

Journal of Clinical Microbiology ◽

10.1128/jcm.36.6.1704-1710.1998 ◽

1998 ◽

Vol 36 (6) ◽

pp. 1704-1710 ◽

Cited By ~ 38

Author(s):

Terry M. Lo ◽

Christine K. Ward ◽

Thomas J. Inzana

Keyword(s):

Early Detection ◽

Multiplex Pcr ◽

Sensitivity And Specificity ◽

Dna Sequences ◽

Capsular Polysaccharide ◽

Actinobacillus Pleuropneumoniae ◽

Pcr Assay ◽

Multiplex Pcr Assay ◽

Detection And Identification ◽

Serotype 5

Serotyping of Actinobacillus pleuropneumoniae is based on detection of the serotype-specific capsular antigen. However, not all isolates can be serotyped, and some may cross-react with multiple serotyping reagents. To improve sensitivity and specificity of serotyping and for early detection, a multiplex PCR assay was developed for detection of A. pleuropneumoniae and identification of serotype 5 isolates. DNA sequences specific to the conserved export and serotype-specific biosynthesis regions of the capsular polysaccharide of A. pleuropneumoniaeserotype 5 were used as primers to amplify 0.7- and 1.1-kb DNA fragments, respectively. The 0.7-kb fragment was amplified from all strains of A. pleuropneumoniae tested with the exception of serotype 4. The 0.7-kb fragment was not amplified from any heterologous species that are also common pathogens or commensals of swine. In contrast, the 1.1-kb fragment was amplified from all serotype 5 strains only. The assay was capable of amplifying DNA from less than 102 CFU. The A. pleuropneumoniaeserotype 5 capsular DNA products were readily amplified from lung tissues obtained from infected swine, although the 1.1-kb product was not amplified from some tissues stored frozen for 6 years. The multiplex PCR assay enabled us to detect A. pleuropneumoniae rapidly and to distinguish serotype 5 strains from other serotypes. The use of primers specific to the biosynthesis regions of other A. pleuropneumoniae serotypes would expand the diagnostic and epidemiologic capabilities of this assay.

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“Pathotyping” Multiplex PCR Assay for Haemophilus parasuis: a Tool for Prediction of Virulence

Journal of Clinical Microbiology ◽

10.1128/jcm.02464-16 ◽

2017 ◽

Vol 55 (9) ◽

pp. 2617-2628 ◽

Cited By ~ 8

Author(s):

Kate J. Howell ◽

Lucy A. Weinert ◽

Sarah E. Peters ◽

Jinhong Wang ◽

Juan Hernandez-Garcia ◽

...

Keyword(s):

Multiplex Pcr ◽

Generalized Linear Model ◽

Bacterial Species ◽

Haemophilus Parasuis ◽

Pcr Assay ◽

Current Standard ◽

Content Type ◽

The United Kingdom ◽

Multiplex Pcr Assay ◽

Upper Respiratory

ABSTRACTHaemophilus parasuisis a diverse bacterial species that is found in the upper respiratory tracts of pigs and can also cause Glässer's disease and pneumonia. A previous pangenome study ofH. parasuisidentified 48 genes that were associated with clinical disease. Here, we describe the development of a generalized linear model (termed a pathotyping model) to predict the potential virulence of isolates ofH. parasuisbased on a subset of 10 genes from the pangenome. A multiplex PCR (mPCR) was constructed based on these genes, the results of which were entered into the pathotyping model to yield a prediction of virulence. This new diagnostic mPCR was tested on 143 field isolates ofH. parasuisthat had previously been whole-genome sequenced and a further 84 isolates from the United Kingdom from cases ofH. parasuis-related disease in pigs collected between 2013 and 2014. The combination of the mPCR and the pathotyping model predicted the virulence of an isolate with 78% accuracy for the original isolate collection and 90% for the additional isolate collection, providing an overall accuracy of 83% (81% sensitivity and 93% specificity) compared with that of the “current standard” of detailed clinical metadata. This new pathotyping assay has the potential to aid surveillance and disease control in addition to serotyping data.

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Usefulness of a Multiplex PCR for Detection of Diarrheagenic Escherichia coli in a Diagnostic Microbiology Laboratory Setting

Bangladesh Journal of Medical Microbiology ◽

10.3329/bjmm.v1i2.21506 ◽

2016 ◽

Vol 1 (2) ◽

pp. 38-42 ◽

Cited By ~ 4

Author(s):

Khairun Nessa ◽

Dilruba Ahmed ◽

Johirul Islam ◽

FM Lutful Kabir ◽

M Anowar Hossain

Keyword(s):

Escherichia Coli ◽

Multiplex Pcr ◽

Clinical Laboratory ◽

Proteinase K ◽

Microbiology Laboratory ◽

Pcr Assay ◽

E Coli ◽

Diarrheagenic Escherichia Coli ◽

Multiplex Pcr Assay ◽

Diagnostic Microbiology

A multiplex PCR assay was evaluated for diagnosis of diarrheagenic Escherichia coli in stool samples of patients with diarrhoea submitted to a diagnostic microbiology laboratory. Two procedures of DNA template preparationproteinase K buffer method and the boiling method were evaluated to examine isolates of E. coli from 150 selected diarrhoeal cases. By proteinase K buffer method, 119 strains (79.3%) of E. coli were characterized to various categories by their genes that included 55.5% enteroaggregative E. coli (EAEC), 18.5% enterotoxigenic E. coli (ETEC), 1.7% enteropathogenic E. coli (EPEC), and 0.8% Shiga toxin-producing E. coli (STEC). Although boiling method was less time consuming (<24 hrs) and less costly (<8.0 US $/ per test) but was less efficient in typing E. coli compared to proteinase K method (41.3% vs. 79.3% ; p<0.001). The sensitivity and specificity of boiling method compared to proteinase K method was 48.7% and 87.1% while the positive and negative predictive value was 93.5% and 30.7%, respectively. The majority of pathogenic E. coli were detected in children (78.0%) under five years age with 53.3% under one year, and 68.7% of the children were male. Children under 5 years age were frequently infected with EAEC (71.6%) compared to ETEC (24.3%), EPEC (2.7%) and STEC (1.4%). The multiplex PCR assay could be effectively used as a rapid diagnostic tool for characterization of diarrheagenic E. coli using a single reaction tube in the clinical laboratory setting.Bangladesh J Med Microbiol 2007; 01 (02): 38-42

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