Feasibility of the Interferon-γ Release Assay for the Diagnosis of Genitourinary Tuberculosis in an Endemic Area

Introduction: Brucellosis, caused by Brucella abortus (B. abortus), is an important zoonosis posing a great risk to both livestock and humans. Currently, most assays for clinical diagnosis of brucellosis have been developed based on serological principles; however, these assays have a number of limitations and disadvantages. Methodology: To address this concern, the aim of this study was to develop a gamma interferon (IFN-γ) release assay (IGRA) for the diagnosis of brucellosis. Towards this end, the stimulating effect induced by different somatic antigens of B. abortus on the secretion of IFN-γ was evaluated. Results: The best antigen candidate, B. abortus strain 2308, able to induce high levels of IFN-γ expression in peripheral blood (PB) cells from cattle, was used for the development of the IGRA. The optimal concentration for stimulation was determined as 1.0×107 CFU/mL. This study demonstrated that IFN-γ was detectable on day 5 post infection (p.i.) and peaked on day 14 p.i.. Finally, the IGRA developed was used for detection of B. abortus in clinical samples, and a higher level of IFN-γ was detected in Brucella-infected samples compared to vaccination samples and negative controls. Conclusions: The optimal somatic antigen for B. abortus was identified and used to establish a robust IGRA. The IGRA developed is suitable for clinical diagnosis of brucellosis, especially in the early stages of infection.

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Prediction of the risk of active tuberculosis in HIV-infection with an interferon-γ release assay

The Lancet ◽

10.1016/s0140-6736(13)62264-3 ◽

2013 ◽

Vol 382 ◽

pp. S16

Author(s):

Susan Shin-Jung Lee ◽

Hsi-Hsun Lin ◽

Hung-Chin Tsai ◽

Ih-Jen Su ◽

Cheng-Len Sy ◽

...

Keyword(s):

Hiv Infection ◽

Interferon Γ ◽

Active Tuberculosis ◽

Release Assay

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Abdominal tuberculosis with a Pseudo-Sister Mary Joseph nodule mimicking peritoneal carcinomatosis

BMJ Case Reports ◽

10.1136/bcr-2019-229624 ◽

2019 ◽

Vol 12 (6) ◽

pp. e229624 ◽

Cited By ~ 1

Author(s):

Amine Awad ◽

Tom Pampiglione ◽

Zaker Ullah

Keyword(s):

Transvaginal Ultrasound ◽

Positive Culture ◽

Ct Scanning ◽

Abdominal Tuberculosis ◽

Tumour Marker ◽

Interferon Γ ◽

Ca 125 ◽

Fluid Analysis ◽

Release Assay ◽

Sister Mary Joseph

A 46-year-old woman presented in severe abdominal pain on a background of 3 months of weight loss and intermittent vomiting. She had visited East Africa 6 months prior but reported no unwell contacts. On examination, she had generalised abdominal tenderness, distension and a painful paraumbilical swelling. CT scanning confirmed small bowel obstruction and revealed widespread peritoneal nodules, lymphadenopathy, ascites and a soft tissue paraumbilical mass. CA-125 tumour marker was elevated. However, transvaginal ultrasound scanning showed normal-appearing ovaries. She underwent a diagnostic laparoscopy for ascitic fluid analysis and biopsy of omental and peritoneal nodules, which revealed a lymphocytic exudate and caseating granulomas, respectively. Interferon-γ release assay and repeated stains for acid-fast bacilli were negative. She was commenced on antituberculous chemotherapy for a presumed diagnosis of abdominal tuberculosis. Positive culture results 2 weeks later confirmed Mycobacterium tuberculosis infection. The patient experienced a complete resolution of symptoms within 6 weeks of treatment.

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Host factors associated to false negative and indeterminate results in an interferon‐γ release assay in patients with active tuberculosis

Pulmonology ◽

10.1016/j.pulmoe.2019.11.001 ◽

2020 ◽

Vol 26 (6) ◽

pp. 353-362 ◽

Cited By ~ 1

Author(s):

J.A. Santos ◽

R. Duarte ◽

C. Nunes

Keyword(s):

False Negative ◽

Interferon Γ ◽

Active Tuberculosis ◽

Host Factors ◽

Factors Associated ◽

Release Assay

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A Semi-Automated Tuberculosis Testing Workflow Reduces Manual Hazardous Sample Handling and Hands-On Time: A Proof-of-Concept Study

SLAS TECHNOLOGY Translating Life Sciences Innovation ◽

10.1177/2472630319884519 ◽

2019 ◽

Vol 25 (3) ◽

pp. 253-257

Author(s):

Kevin W. P. Miller ◽

Neil Grossman ◽

Peter Haviernik ◽

John Wolff ◽

Chih-lung Fu ◽

...

Keyword(s):

Processing System ◽

Interferon Γ ◽

Sample Processing ◽

Diagnostic Laboratory ◽

Laboratory Staff ◽

Manual Intervention ◽

Automated Processing ◽

Release Assay ◽

Multiple Blood ◽

Repetitive Strain

A central tenet of good diagnostic laboratory practice is protecting laboratory staff from contact with sample-borne pathogens and dangerous chemicals. Automated sample-processing systems can reduce or eliminate the risk of exposure to infectious samples while providing results on par with, or better than, those from manually processed samples. In addition, hands-free automated processing may enable analysts to focus on higher order activities while eliminating the risk of repetitive strain injuries associated with manual pipetting. Here, we describe a semi-automated tuberculosis interferon-γ release assay (IGRA) workflow that includes an automated high-throughput sample-processing system. The system automates cap removal, automates sample mixing and aspiration of blood from lithium heparin collection tubes, and aliquots blood samples into multiple blood assay tubes for downstream testing without manual intervention. We show that automated results are comparable to manual methods without risk of analyst exposure or repetitive strain injury.

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