scholarly journals Laboratory diagnosis ofMycoplasma pneumoniaeinfection: 2. Comparison of methods for the direct detection of specific antigen or nucleic acid sequences in respiratory exudates

1988 ◽  
Vol 101 (3) ◽  
pp. 685-694 ◽  
Author(s):  
R. Harris ◽  
B. P. Marmion ◽  
G. Varkanis ◽  
T. Kok ◽  
B. Lunn ◽  
...  
Keyword(s):  
Mycoplasma Pneumoniae ◽  
Direct Detection ◽  
Cdna Probe ◽  
Specific Antigen ◽  
Diagnostic System ◽  
Laboratory Diagnosis ◽  
Mycoplasma Species ◽  
Rna Sequences ◽  
Current Infection ◽  
Probe Assay

SUMMARYThe efficiency of the direct detection ofMycoplasma pneumoniaein respiratory exudates by an antigen capture, indirect enzyme immunoassay (Ag-EIA), has been compared with its detection with a cDNA probe (‘Gen-Probe assay’) directed against the specific ribosomal RNA sequences of the organism (‘Mycoplasma pneumoniaeRapid Diagnostic System’, Gen-Probe, San Diego, California).Both assays showed excellent specificity against a range of mycoplasma species suspended in negative nasopharyngeal aspirates; onlyM. pneumoniaeandM. genitaliumreacted. In experiments with graded doses of viableM. pneumoniaecells suspended in negative nasopharyngeal aspirate, the Gen-Probe assay was more sensitive than Ag-EIA; detection limits were respectively 2 × 103 c.f.u./ml (3·2 × 105genomes) and 2·5 × 104c.f.u./ml (4 × 106genomes); detection levels 10–100 times less sensitive than culture.The two assays were also tested on nasopharyngeal aspirates or sputum specimens from 90 patients with respiratory infection; 67 of these were culture-or seronegative forM. pneumoniaeand 23 were culture-or seropositive. Ag-EIA detected 21 (91%) of the latter but the Gen-Probe assay detected only 5 (22%). Both assays were negative with the 67 culture-/sero-negatives; there were no Gen-Probe assay positive/Ag-EIA negatives.Overall, it is concluded that although Ag-EIA and the Gen-Probe assay are effective substitutes for culture as a diagnostic procedure, there is a significant problem with samples which are culture-negative and from patients who have good serological evidence of current infection. Possible reasons for the disparity between the two assays are advanced.

scholarly journals Laboratory diagnosis ofMycoplasma pneumoniaeinfection. 4. Antigen capture and PCR-gene amplification for detection of the mycoplasma: problems of clinical correlation

1992 ◽  
Vol 109 (3) ◽  
pp. 519-537 ◽  
Author(s):  
J. Williamson ◽  
B. P. Marmion ◽  
D. A. Worswick ◽  
T. -W. Kok ◽  
G. Tannock ◽  
...  
Keyword(s):  
Direct Detection ◽  
Pcr Amplification ◽  
Laboratory Diagnosis ◽  
Capture Assay ◽  
Antigen Capture ◽  
Specificity And Sensitivity ◽  
Antibody Assays ◽  
Clinical Episode ◽  
Previous Infection ◽  
Current Infection

SUMMARYDirect detection assays forMycoplasma pneumoniaewere established by PCR amplification of short sequences within the foot protein/adhesin (P1) gene and the 16S ribosomal RNA gene.Specificity and sensitivity was excellent, no hybridization was observed withM. genitaliumand other humanMycoplasmaspecies. In nose and throat washings from subjects with respiratory infection a pattern of high counts (c.f.u./ml) ofM. pneumoniae(deduced from the amount of amplified PCR product), and a positive antigen capture assay, was found in 83% of subjects with serological evidence of current infection withM. pneumoniae.A small proportion of subjects with serological patterns suggesting infection in the more distant past had positive PCR assays. This was considered to represent either persistence of the organism from a previous infection or perhaps transient carriage during a reinfection, without substantial change in antibody response.PCR-based assay ofM. pneumoniaeoffers a powerful, rapid, and sensitive substitute for culture of the mycoplasma. Antigen capture, while less sensitive than PCR, offers the advantage that it is more often positive with samples from current infection and requires less stringent laboratory organization to contain false positive results. We conclude however that the laboratory diagnosis of a chosen clinical episode should not rest on the PCR or Ag-EIA assays alone, but must also include antibody assays to confirm whether infection is current or represents persistence from past exposure.

scholarly journals Role of Serum Mycoplasma pneumoniae IgA, IgM, and IgG in the Diagnosis of Mycoplasma pneumoniae-Related Pneumonia in School-Age Children and Adolescents

2016 ◽  
Vol 24 (1) ◽  
Author(s):  
Wei-Ju Lee ◽  
Eng-Yen Huang ◽  
Chih-Min Tsai ◽  
Kuang-Che Kuo ◽  
Yi-Chuan Huang ◽  
...  
Keyword(s):  
Children And Adolescents ◽  
Mycoplasma Pneumoniae ◽  
Immunoglobulin A ◽  
Fold Increase ◽  
Laboratory Diagnosis ◽  
Diagnostic Value ◽  
Immunoglobulin M ◽  
School Age Children ◽  
School Age ◽  
Content Type

ABSTRACT Mycoplasma pneumoniae is an important causative pathogen of community-acquired pneumonia in children. Rapid and reliable laboratory diagnosis of M. pneumoniae infection is important so that appropriate antibiotic treatment can be initiated to reduce the misuse of drugs and resistance rates. Anti-M. pneumoniae immunoglobulin M (IgM) is an indicator of recent primary infection but can persist for several months after initial infection. It has been suggested that anti-M. pneumoniae immunoglobulin A (IgA) can be a reliable indicator for recent M. pneumoniae infection in adults. We investigated the clinical diagnostic value of M. pneumoniae IgA in school-age children and adolescents with M. pneumoniae-related pneumonia. Eighty children with pneumonia and seropositive for M. pneumoniae IgM or with a 4-fold increase of anti-M. pneumoniae immunoglobulin G (IgG) were enrolled from May 2015 to March 2016. The titers of M. pneumoniae IgA, IgM, and IgG, the clinical features, and laboratory examinations of blood, C-reactive protein, and liver enzymes were analyzed. The initial positivity rates for M. pneumoniae IgM and IgA upon admission to the hospital were 63.6 and 33.8%, respectively. One week after admission, the cumulative positivity rates for M. pneumoniae IgM and IgA increased to 97.5 and 56.3%, respectively. Detection of M. pneumoniae IgM was more sensitive than detection of M. pneumoniae IgA for the diagnosis of M. pneumoniae-related pneumonia in school-age children and adolescents; however, paired sera are necessary for a more accurate diagnosis.

scholarly journals Detection and Differentiation of Avian Mycoplasmas by Surface-Enhanced Raman Spectroscopy Based on a Silver Nanorod Array

2011 ◽  
Vol 78 (6) ◽  
pp. 1930-1935 ◽  
Author(s):  
Suzanne L. Hennigan ◽  
Jeremy D. Driskell ◽  
Naola Ferguson-Noel ◽  
Richard A. Dluhy ◽  
Yiping Zhao ◽  
...  
Keyword(s):  
Raman Spectroscopy ◽  
Sensitivity And Specificity ◽  
Limit Of Detection ◽  
Direct Detection ◽  
Nanorod Array ◽  
Surface Enhanced Raman Spectroscopy ◽  
Mycoplasma Species ◽  
Content Type ◽  
Surface Enhanced ◽  
Surface Enhanced Raman

ABSTRACTMycoplasma gallisepticumis a bacterial pathogen of poultry that is estimated to cause annual losses exceeding $780 million. The National Poultry Improvement Plan guidelines recommend regular surveillance and intervention strategies to containM. gallisepticuminfections and ensure mycoplasma-free avian stocks, but several factors make detection ofM. gallisepticumand diagnosis ofM. gallisepticuminfection a major challenge. Current techniques are laborious, require special expertise, and are typically plagued by false results. In this study, we describe a novel detection strategy which uses silver nanorod array–surface-enhanced Raman spectroscopy (NA-SERS) for direct detection of avian mycoplasmas. As a proof of concept for use in avian diagnostics, we used NA-SERS to detect and differentiate multiple strains of avian mycoplasma species, includingAcholeplasma laidlawii,Mycoplasma gallinarum,Mycoplasma gallinaceum,Mycoplasma synoviae, andM. gallisepticum, including vaccine strains 6/85, F, and ts-11. Chemometric multivariate analysis of spectral data was used to classify these species rapidly and accurately, with >93% sensitivity and specificity. Furthermore, NA-SERS had a lower limit of detection that was 100-fold greater than that of standard PCR and comparable to that of real-time quantitative PCR. Detection ofM. gallisepticumin choanal cleft swabs from experimentally infected birds yielded good sensitivity and specificity, suggesting that NA-SERS is applicable for clinical detection.

scholarly journals SynMyco transposon: engineering transposon vectors for efficient transformation of minimal genomes

DNA Research ◽  
2019 ◽  
Vol 26 (4) ◽  
pp. 327-339 ◽  
Author(s):  
Ariadna Montero-Blay ◽  
Samuel Miravet-Verde ◽  
Maria Lluch-Senar ◽  
Carlos Piñero-Lambea ◽  
Luis Serrano
Keyword(s):  
Antibiotic Resistance ◽  
Synthetic Biology ◽  
Genome Editing ◽  
Mycoplasma Pneumoniae ◽  
Mycoplasma Gallisepticum ◽  
Model Organisms ◽  
Mycoplasma Species ◽  
Resistance Marker ◽  
Antibiotic Resistance Marker ◽  
Reference Tool

Abstract Mycoplasmas are important model organisms for Systems and Synthetic Biology, and are pathogenic to a wide variety of species. Despite their relevance, many of the tools established for genome editing in other microorganisms are not available for Mycoplasmas. The Tn4001 transposon is the reference tool to work with these bacteria, but the transformation efficiencies (TEs) reported for the different species vary substantially. Here, we explore the mechanisms underlying these differences in four Mycoplasma species, Mycoplasma agalactiae, Mycoplasma feriruminatoris, Mycoplasma gallisepticum and Mycoplasma pneumoniae, selected for being representative members of each cluster of the Mycoplasma genus. We found that regulatory regions (RRs) driving the expression of the transposase and the antibiotic resistance marker have a major impact on the TEs. We then designed a synthetic RR termed SynMyco RR to control the expression of the key transposon vector elements. Using this synthetic RR, we were able to increase the TE for M. gallisepticum, M. feriruminatoris and M. agalactiae by 30-, 980- and 1036-fold, respectively. Finally, to illustrate the potential of this new transposon, we performed the first essentiality study in M. agalactiae, basing our study on more than 199,000 genome insertions.

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