skin-diseases-and-microbiology-2016_posters-abstracts

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Volume 4, Issue 7(Suppl) J Infect Dis Ther 2016
ISSN: 2332-0877, JIDT an open access journal
Page 58
Skin Diseases & Microbiology 2016
October 03-05, 2016
conferenceseries.com
October 03-05, 2016 Vancouver, Canada
International Conference on
Infectious Diseases, Diagnostic Microbiology &
Dermatologists Summit on Skin Infections
Direct application of loop mediated isothermal amplification assay for detection of Mycoplasma bovis in
mastitic milk
Aqeela Ashraf
University of Veterinary and Animal Sciences, Pakistan
Mycoplasma mastitis is always difficult to control due to lack of rapid and accurate diagnostic tool. The diagnostic methods
available are mostly time consuming due to laborious culturing requirement, expensive, non-specific and less sensitive like
biochemical tests and conventional PCR assay. A loop mediated isothermal amplification (LAMP) assay was developed for detection
of Mycoplasma bovis (M. bovis ) directly from clinical mastitic milk samples. The LAMP assay was developed and validated on clinical
samples obtained from M. bovis and other mastitis-causing pathogens detected by MALDI-TOF. 3 different sets of primers were
used targeting different gene regions of M. bovis. The genes selected were UvrC, 16S rRNA and GyrB region. LAMP conditions were
optimized for each of these and the efficiency, sensitivity and specificity of these LAMP primers were evaluated and compared. The
result of 16S rRNA primers was more sensitive while GyrB primers were more specific. To confirm the specificity of the developed
assay, other bacterial strains used were Mycoplasma agalactiae, Escherichia coli, Staphylococcus aureus, Streptococcus agalactiae,
Streptococcus dysgalactiae and Streptococcus uberis. No cross reactivity was observed in all of the primer sets. Results were also
compared to conventional PCR assay with primers chosen from the same genes and confirmed by sequencing. For the evaluation of
LAMP assay sensitivity, culture-positive milk samples were subjected to the assay. LAMP assay detected M. bovis in some of those
milk samples which were PCR negative. In the present study we have developed, validated and evaluated LAMP assay for detection
of M. bovis from mastitis milk samples. The assay is authentic, rapid and sensitive.
Novel T-cell assays for the discrimination of active and latent tuberculosis infection: The diagnostic value
of PPE family
Shima Mahmoudi, Setareh Mamishi and Babak Pourakbari
Tehran University of Medical Sciences, Iran
The diagnosis of active and latent tuberculosis remains a challenge. Although a new approach based on detecting Mycobacterium
tuberculosis-specific T-cells has been introduced, it cannot distinguish between latent infection and active disease. The aim of this
study was to evaluate the diagnostic potential of interleukin-2 (IL-2) as biomarker after specific antigen stimulation with PE35 and
PPE68 for the discrimination of active and latent tuberculosis infection (LTBI). The production of IL-2 was measured in the antigen-
stimulated whole-blood supernatants following stimulation with recombinant PE35 and PPE68. The discrimination performance
(assessed by the area under ROC curve) for IL-2 following stimulation with recombinant PE35 and PPE68 between LTBI and patients
with active TB were 0.837 [95% confidence interval (CI) 0.72-0.97] for LTBI diagnosis and 0.75 (95% CI 0.63-0.89) for active TB
diagnosis, respectively. Applying the 6.4 pg/mL cut-off for IL-2 induced by PE35 in the present study population resulted in sensitivity
of 78%, specificity of 83%, PPV of 83% and NPV of 78% for the discrimination of active TB and LTBI. In addition, a sensitivity of
81%, specificity of 71%, PPV of 68 and 83% of NPV was reported based on the 4.4 pg/mL cut-off for IL-2 induced by PPE68. This
study confirms IL-2 induced by PE35 and PPE68 as a sensitive and specific biomarker and highlights IL-2 as new promising adjunct
markers for discriminating of LTBI and active TB disease.
J Infect Dis Ther 2016, 4:7(Suppl)