Utilization of a real-time PCR approach for Haemophilus influenzae serotype determination as an alternative to the slide agglutination test

2013 ◽  
Vol 27 (2) ◽  
pp. 86-89 ◽  
Author(s):  
Danielle Wroblewski ◽  
Tanya A. Halse ◽  
Jill Hayes ◽  
Donna Kohlerschmidt ◽  
Kimberlee A. Musser
Keyword(s):  
Haemophilus Influenzae ◽  
Real Time ◽  
Real Time Pcr ◽  
Agglutination Test ◽  
Slide Agglutination ◽  
Slide Agglutination Test

scholarly journals Methods for serotyping nasopharyngeal isolates of Haemophilus influenzae: slide agglutination, Quellung reaction, countercurrent immunoelectrophoresis, latex agglutination, and antiserum agar

1979 ◽  
Vol 9 (5) ◽  
pp. 570-574
Author(s):  
D L Ingram ◽  
A M Collier ◽  
E Pendergrass ◽  
S H King
Keyword(s):  
Haemophilus Influenzae ◽  
Latex Agglutination ◽  
Agglutination Test ◽  
Nasopharyngeal Swab ◽  
Immunofluorescence Test ◽  
Slide Agglutination ◽  
Slide Agglutination Test ◽  
Rapid Tests ◽  
Quellung Reaction ◽  
Multiple Samples

Nasopharyngeal isolates of H. influenzae were typed by the slide agglutination test, the Quelling reaction, the latex agglutination test, countercurrent immunoelectrophoresis, and the antiserum agar test. These tests gave essentially comparable results, with countercurrent immunoelectrophoresis and latex agglutination being slightly more sensitive. Cross-reactive problems encountered with latex agglutination and the expense of performing countercurrent immunoelectrophoresis or the antiserum agar test made these tests less practical than the slide agglutination test to identify single strains that were already isolated. The Quellung reaction and slide agglutination were the most rapid tests used to type an organism. For mass screening of multiple samples, countercurrent immunoelectrophoresis was the simplest technique. The antiserum agar test was slow but was the best technique to screen nasopharyngeal swab cultures to identify the presence of any encapsulated strains in the mixed flora. Whether any of the above techniques were as sensitive as the immunofluorescence test was not evaluated in this study.

scholarly journals Evaluation of Real-Time Polymerase Chain Reaction in Culture-Negative Cerebrospinal Fluid Samples of Bacterial meningitis Patients

2021 ◽  
pp. 96-101
Author(s):  
C. P. Khuntia ◽  
S. K. Kar ◽  
B. Dwibedi
Keyword(s):  
Streptococcus Pneumoniae ◽  
Bacterial Meningitis ◽  
Haemophilus Influenzae ◽  
Real Time ◽  
Real Time Pcr ◽  
Latex Agglutination ◽  
Agglutination Test ◽  
Chain Reaction ◽  
Polymerase Chain ◽  
Culture Negative

Background: Meningitis is a rigorous childhood disease with high morbidity and mortality. It is the main cause of under five mortality in India. Mainly three bacteria Streptococcus pneumoniae, Neisseria meningitidis, and Haemophilus influenzae are responsible. In low economic set up country like India, documented bacterial meningitis  mainly depend on gram staining, cerebrospinal fluid (CSF) culture results or latex agglutination test resulting in less number of positive due to the prior antimicrobial intake which affects culture and latex agglutination test results. This study was taken up rapid and accurate molecular method like RT PCR to diagnose bacterial meningitis in culture-negative CSF samples. Materials and Methods: Fifty culture-negative CSF samples from suspected cases of bacterial meningitis were examined by real-time polymerase chain reaction (real-time PCR) for the presence of lytA, bexA, and ctrA genes specific for Streptococcus pneumoniae, Haemophilus influenzae, and Neisseria meningitidis respectively. Results: Positive real-time PCR results for Streptococcus pneumoniae were detected in 36 (72%) of culture-negative CSF samples while 10% positive results for Haemophilus influenzae type b. Nine  (18%) samples were negative by real-time PCR for all tested organisms. Conclusion: The use of molecular techniques as real-time PCR can provide a valuable addition to the proportion of diagnosed cases of bacterial meningitis especially in settings with high rates of culture-negative results.

scholarly journals Haemophilus influenzae Meningitis Direct Diagnosis by Metagenomic Next-Generation Sequencing: A Case Report

Pathogens ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 461
Author(s):  
Madjid Morsli ◽  
Quentin Kerharo ◽  
Jeremy Delerce ◽  
Pierre-Hugues Roche ◽  
Lucas Troude ◽  
...  
Keyword(s):  
Next Generation Sequencing ◽  
Haemophilus Influenzae ◽  
Real Time ◽  
Real Time Pcr ◽  
Point Of Care ◽  
Next Generation ◽  
Oxford Nanopore ◽  
Sequence Encoding ◽  
Oxford Nanopore Technologies ◽  
Generation Sequencing

Current routine real-time PCR methods used for the point-of-care diagnosis of infectious meningitis do not allow for one-shot genotyping of the pathogen, as in the case of deadly Haemophilus influenzae meningitis. Real-time PCR diagnosed H. influenzae meningitis in a 22-year-old male patient, during his hospitalisation following a more than six-metre fall. Using an Oxford Nanopore Technologies real-time sequencing run in parallel to real-time PCR, we detected the H. influenzae genome directly from the cerebrospinal fluid sample in six hours. Furthermore, BLAST analysis of the sequence encoding for a partial DUF417 domain-containing protein diagnosed a non-b serotype, non-typeable H.influenzae belonging to lineage H. influenzae 22.1-21. The Oxford Nanopore metagenomic next-generation sequencing approach could be considered for the point-of-care diagnosis of infectious meningitis, by direct identification of pathogenic genomes and their genotypes/serotypes.

scholarly journals Antibodies produced by dogs successfully challenged with live Leptospira spp. did not cross-react to Brucella antigen in a commercial rapid slide agglutination test that detects antibodies to Brucella canis

2018 ◽  
Vol 31 (1) ◽  
pp. 83-85
Author(s):  
Matthew R. Krecic
Keyword(s):  
Cross Reactivity ◽  
Agglutination Test ◽  
Slide Agglutination ◽  
Serologic Tests ◽  
Experimental Infections ◽  
Negative Results ◽  
Brucella Canis ◽  
Slide Agglutination Test ◽  
Leptospira Spp ◽  
Canine Brucellosis

Brucella canis is a cause of canine infertility and abortion. Veterinarians and veterinary laboratorians screen for antibodies to B. canis with serologic tests including a rapid slide agglutination test (RSAT; D-Tec CB, Zoetis, San Diego, CA). False-positive results are possible because of cross-reactivity to antibodies to some gram-negative bacteria. Cross-reactivity has been reported between antibodies of Brucella abortus and Leptospira spp. with serologic tests for bovine brucellosis; however, this has not been documented with serologic tests for canine brucellosis, to the author’s knowledge. The RSAT was evaluated with the sera from dogs experimentally challenged with 1 of 4 serovars of Leptospira spp.: L. kirschneri serovar Grippotyphosa, or L. interrogans serovars Canicola, Icterohaemorrhagiae, or Pomona. Experimental infections were confirmed through results of microscopic agglutination testing and/or lateral flow immunochromatography testing. The sera of 32 dogs collected at day 0 and days 7, 10, and 14 yielded negative results with the RSAT. Antibodies produced through experimental infections to these 4 serovars of Leptospira spp. did not cross-react with Brucella antigen with the RSAT; therefore, cross-reactivity of anti-leptospiral antibodies may not be of concern for B. canis rapid slide agglutination testing of dogs.

scholarly journals A slide agglutination test for the exclusion and diagnosis of typhoid fever

1939 ◽  
Vol 39 (3) ◽  
pp. 294-297 ◽  
Author(s):  
F. M. Berger ◽  
G. Brecher
Keyword(s):  
Typhoid Fever ◽  
Positive Result ◽  
Agglutination Test ◽  
Serological Diagnosis ◽  
Agglutination Reaction ◽  
Negative Test ◽  
Slide Agglutination ◽  
Peculiar Behaviour ◽  
Slide Agglutination Test ◽  
Agglutination Method

A sensitive antigen suspension is described for use with a simple slide agglutination method which makes possible a serological diagnosis or exclusion of typhoid fever without recourse to a laboratory. The method has been tested on 414 sera sent to our laboratory; it detected all cases with a titre of 1: 80 or more, and most of those with a titre of 1: 40. The method was further tested on 130 clinically observed cases, in which it gave satisfactory results. The S. A. method gave a positive result with 98 out of 100 sera from patients with typhoid fever, whereas the classical Widal reaction gave a positive result with 68 of them only.The intensity and rapidity of the slide agglutination reaction provide a rough measure of the titre of a serum. A quick and distinct agglutination indicates a titre of 1: 80 or more and is diagnostic of typhoid fever. A slow and indistinct result is obtained when the titre of the serum is about 1: 40. A negative test indicates with great probablity that a diagnosis of typhoid fever may be excluded.We think the method succeeds because the nature of the suspension employed and the peculiar behaviour of slide agglutinations permit the detection of O agglutinins as well as H agglutinins.

scholarly journals Airway dysbiosis: Haemophilus influenzae and Tropheryma in poorly controlled asthma

2015 ◽  
Vol 47 (3) ◽  
pp. 792-800 ◽  
Author(s):  
Jodie L. Simpson ◽  
Joshua Daly ◽  
Katherine J. Baines ◽  
Ian A. Yang ◽  
John W. Upham ◽  
...  
Keyword(s):  
Haemophilus Influenzae ◽  
Bacterial Diversity ◽  
Real Time ◽  
Real Time Pcr ◽  
Bacterial Species ◽  
Inflammatory Disorder ◽  
Eosinophilic Asthma ◽  
Chronic Inflammatory Disorder ◽  
16S Rrna Pyrosequencing ◽  
Airway Microbiome

Asthma is a chronic inflammatory disorder of the airways where bacteria may act as protagonists of chronic inflammation. Little is known about the relation of airway inflammation to the presence of specific bacterial taxa. We sought to describe the sputum microbiome in adults with poorly controlled asthma.DNA was extracted from induced sputum and microbial communities were profiled using 16S rRNA pyrosequencing. Bacterial species were characterised, and the relationship between microbial populations, asthma inflammatory subtypes and other covariates was explored. Real-time PCR was used to identify Tropheryma whipplei and Haemophilus influenzae in sputum.Adults with neutrophilic asthma had reduced bacterial diversity and species richness. Tropheryma was identified and confirmed with real-time PCR in 12 (40%) participants. Haemophilus occurred most often in a group of younger atopic males with an increased proportion of neutrophils. PCR confirmed the presence of H. influenzae in 35 (76%) participants with poorly controlled asthma.There are phenotype-specific alterations to the airway microbiome in asthma. Reduced bacterial diversity combined with a high prevalence of H. influenzae was observed in neutrophilic asthma, whereas eosinophilic asthma had abundant T. whipplei.

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