QuantiFERON-TB GOLD ELISA assay for the detection ofMycobacterium tuberculosis-specific antigens in blood specimens of HIV-positive patients in a high-burden country

ABSTRACT Clonal complexity is increasingly accepted in Mycobacterium tuberculosis infection, including mixed infections by ≥2 strains, which usually occur in settings with a high burden of tuberculosis and/or a high risk of overexposure to infected patients. Mixed infections can hamper diagnostic procedures; obtaining an accurate antibiogram is difficult when the susceptibility patterns of the strains differ. Here, we show how mixed infections can also prove challenging for other diagnostic procedures, even outside settings where mixed infections are traditionally expected. We show how an unnoticed mixed infection in an HIV-positive patient diagnosed in Madrid, Spain, with differences in the representativeness of the coinfecting strains in different sputum samples, markedly complicated the resolution of a laboratory cross-contamination false positivity alert.

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OC 8405 IDENTIFICATION OF AN MTB-SPECIFIC SOLUBLE HOST SIGNATURE FOR RISK OF DEVELOPMENT OF ACTIVE TB IN HIV-POSITIVE MTB-EXPOSED CONTACTS

BMJ Global Health ◽

10.1136/bmjgh-2019-edc.10 ◽

2019 ◽

Vol 4 (Suppl 3) ◽

pp. A5.1-A5

Author(s):

Joseph Mendy ◽

Novel N Chegou ◽

Harriet Mayanja-Kizza ◽

Kim Stanley ◽

Bonnie Thiel ◽

...

Keyword(s):

At Risk ◽

Cost Effective ◽

Interventional Therapy ◽

Hiv Positive ◽

African Countries ◽

Makerere University ◽

Cost Effective Approach ◽

Specific Antigens ◽

Therapy Strategies ◽

Active Disease

BackgroundWith 2 billion people infected with Mycobacterium tuberculosis (Mtb) worldwide, identification of those most at-risk of progressing to active disease would provide a targeted, cost-effective approach for preventative therapy strategies. The GC6–74 project recruited Mtb-exposed HIV-positive (HIV+) contacts from 5 African countries with the aim of identifying molecular and protein signatures for identification of ‘at-risk’ subjects by comparing those who progressed to active disease (progressors) to those who remained asymptomatic (controls).MethodsFor this arm of the project, we analysed longitudinal samples from 12 HIV +progressors and 28 HIV +matched controls from Uganda (Makerere University, MAK) and South Africa (Stellenbosch University, SUN). Diluted whole blood was stimulated for 7 days with 7 Mtb-specific antigens plus controls. Supernatant was collected and a 38-plex multiplex assay performed following identification of confirmed progressors and controls.ResultsThe median time to progression to active disease was 510 days for SUN and 425 days for MAK participants. Baseline CD4 counts were 163 cells/µl for progressors and 154 cells/µl for controls. Baseline responses showed significantly lower IL-4 production in progressors following ESAT-6/CFP-10 (EC) stimulation (p=0.0309) and significantly higher macrophage-derived chemokine (MDC) following both Rv3019 and TB10.4 stimulation. For the time-point closest to progression, IL-10 production following EC stimulation and IFN-γ production following Rv3019 stimulation were significantly higher in progressors than controls (p=0.0024 and p=0.0028 respectively). A combination of 12 analytes following EC and TB10.4 stimulation gave 84.4% and 91.1% correct classification respectively.ConclusionWe have defined a soluble signature for detecting likely progression to active TB in HIV +subjects 1 year prior to progression. Following validation in other cohorts, this could be exploited for development of a field-friendly test for targeted interventional therapy.

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Rapid Extraction of DNA using Ion Exchange Resin for Early Detection ofMycobacterium tuberculosis by the Polymerase Chain Reaction

Tuberculosis and Respiratory Diseases ◽

10.4046/trd.1996.43.1.30 ◽

1996 ◽

Vol 43 (1) ◽

pp. 30

Author(s):

Cheol Min Kim ◽

Seung Kyu Park ◽

Mal Hyun Shon ◽

Young Kim ◽

Sun Dae Song ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Ion Exchange ◽

Early Detection ◽

Exchange Resin ◽

Ion Exchange Resin ◽

Chain Reaction ◽

Rapid Extraction ◽

Ofmycobacterium Tuberculosis ◽

Polymerase Chain ◽

Detection Ofmycobacterium Tuberculosis

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Lymphogranuloma venereum genovariants in men having sex with men in Italy

Sexually Transmitted Infections ◽

10.1136/sextrans-2020-054700 ◽

2020 ◽

pp. sextrans-2020-054700

Author(s):

Antonella Marangoni ◽

Claudio Foschi ◽

Federico Tartari ◽

Valeria Gaspari ◽

Maria Carla Re

Keyword(s):

Chlamydia Trachomatis ◽

Lymphogranuloma Venereum ◽

Hiv Positive ◽

Nucleotide Polymorphisms ◽

Single Nucleotide ◽

High Burden ◽

Total Prevalence ◽

Sex With Men ◽

Reference Strains ◽

Over Time

ObjectivesLymphogranuloma venereum (LGV) is an STI caused by Chlamydia trachomatis serovars L1-L3. In Europe, the current epidemic is caused mainly by L2b genovariant, although increasing cases associated with other L2 variants have been reported. Here, we assessed the distribution of rectal LGV genovariants among men having sex with men (MSM) in Italy.MethodsFrom 2016 to 2020, all the anorectal swabs collected from MSM attending the STI Clinic of St. Orsola-Malpighi Hospital in Bologna and positive for C. trachomatis were stored. LGV infection was confirmed by a pmpH PCR, and, subsequently, a fragment of the ompA gene was amplified and sequenced. Sequences were aligned to reference strains representing different LGV variants.ResultsLGV cases accounted for one-third of all chlamydial rectal infections with a total prevalence of 4.1% (76/1852). Total number of LGV cases per year remained constant. LGV was mainly found in symptomatic patients (>65%), older than 30 years, with a high burden of other STIs (63.7% HIV-positive, 35.5% with concurrent rectal gonorrhoea, 19.7% with early syphilis). A decreasing trend in HIV-LGV co-infection was noticed over time. Three main LGV genovariants were detected (L2f, 46.1%; L2b, 23.0%; L2-L2b/D-Da, 16.9%), together with other known L2b variants (mainly L2bV2 and L2bV4). Two novel L2b ompA variants with non-synonymous single-nucleotide polymorphisms were found. Over time, the percentage of L2f cases dropped gradually, with a significant increase in L2-L2b/D-Da cases (p=0.04).ConclusionsIn our area, LGV is endemic among MSM with different circulating genovariants. Active surveillance and genotyping programmes are needed to reduce re-establishing of LGV infection.

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P3.148 High Burden of Extra-GenitalNeisseria Gonorrhoeae, Chlamydia TrachomatisandMycoplasma GenitaliumInfections in Men Who Have Sex, Especially in HIV-Positive

Sexually Transmitted Infections ◽

10.1136/sextrans-2013-051184.0607 ◽

2013 ◽

Vol 89 (Suppl 1) ◽

pp. A194.1-A194 ◽

Cited By ~ 1

Author(s):

H Moi ◽

S Ringvik ◽

A Moghaddam ◽

N Reinton ◽

A O Olsen

Keyword(s):

Hiv Positive ◽

High Burden

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A Systematic Review of the Epidemiology, Immunopathogenesis, Diagnosis, and Treatment of Pleural TB in HIV- Infected Patients

Clinical and Developmental Immunology ◽

10.1155/2012/842045 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 9

Author(s):

A. Aljohaney ◽

K. Amjadi ◽

G. G. Alvarez

Keyword(s):

Systematic Review ◽

Interferon Gamma ◽

Literature Search ◽

Point Of Care ◽

Diagnosis And Treatment ◽

Hiv Positive ◽

Pleural Effusions ◽

Inclusion Criteria ◽

High Burden

Background. High HIV burden countries have experienced a high burden of pleural TB in HIV-infected patients.Objective. To review the epidemiology, immunopathogenesis, diagnosis, and treatment of pleural TB in HIV-infected patients.Methods. A literature search from 1950 to June 2011 in MEDLINE was conducted.Results. Two-hundred and ninety-nine studies were identified, of which 30 met the inclusion criteria. The immunopathogenesis as denoted by cells and cytokine profiles is distinctly different between HIV and HIV-uninfected pleural TB disease. Adenosine deaminase and interferon gamma are good markers of pleural TB disease even in HIV-infected patients. HIV-uninfected TB suspects with pleural effusions commonly have a low yield of TB organisms however the evidence suggests that in dually infected patients smear and cultures have a higher yield. The Gene Xpert MTB/RIF assay has significant potential to improve the diagnosis of pleural TB in HIV-positive patients.Conclusions. Pleural TB in HIV-infected patients has a different immunopathogenesis than HIV-uninfected pleural TB and these findings in part support the differences noted in this systematic review. Research should focus on developing an interferon gamma-based point of care diagnostic test and expansion of the role of Gene Xpert in the diagnosis of pleural TB.

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