Clinical evaluation of QuantiFERON®-TB Gold Plus directly compared with QuantiFERON®-TB Gold In-Tube and T-Spot®.TB for active pulmonary tuberculosis in the elderly.

Abstract

BACKGROUND:

Reduced sensitivity of tuberculosis (TB) interferon-γ release assays (IGRAs) among the elderly has been reported, which is presumably due to diminished immune function. We evaluated the clinical performance of QuantiFERON®-TB Gold plus (QFT-Plus) compared with QuantiFERON®-TB Gold In-Tube (QFT-GIT) and T-Spot®.TB (T-SPOT) in the elderly.

METHODS:

Blood samples for all three IGRAs were drawn at the same time from all the participants. Both CD4 and CD8 T-cell counts in patients' peripheral blood were also measured.

RESULTS:

A total of 142 active pulmonary TB patients (median age: 84, interquartile range; 76-89 years) were recruited. The sensitivities of the tested IGRAs (excluding invalid/indeterminate cases) were as follows: QFT-Plus, 93.6%; QFT-GIT, 91.4%; and T-SPOT 68.1%. QFT-Plus displayed significantly higher sensitivity than T-SPOT (p < 0.00001). All three IGRAs exhibited the same specificity (100%), as assessed using blood samples from healthy, low TB-risk individuals (n = 118; median age: 39, IQR; 32-47 years). Positivity in 43 active TB patients with CD4 T-cell counts <200/μL, 39 of whom were ≥80 years of age, was as follows: QFT-Plus, 83.7%; QFT-GIT, 74.4%; and T-SPOT, 58.1%. The difference between TB2-TB1 of the QFT-Plus assay was statistically correlated with CD8 but not CD4 T-cell counts in blood (r = 0.193, p = 0.0298).

CONCLUSIONS:

QFT-Plus showed high performance in the detection of TB infection in patients irrespective of their advanced age (≥80 years) or lower CD4 counts. QFT-Plus can be useful for the diagnosis of TB infection in all patients, including those who are elderly and/or immunocompromised.

• Authors: Kiyoyasu Fukushima, Toru Kubo, Kazumasa Akagi, Ritsuko Miyashita, Akira Kondo, Naomi Ehara, Takahiro Takazono, Noriho Sakamoto, Hiroshi Mukae
• Journal: Journal of infection and chemotherapy : official journal of the Japan Society of Chemotherapy (J Infect Chemother) Vol. 27 Issue 12 Pg. 1716-1722 (Dec 2021) ISSN: 1437-7780 [Electronic] Netherlands
• PMID: 34412981 (Publication Type: Journal Article)
• Copyright: Copyright © 2021 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Topics

• Adult
• Aged
• Aged, 80 and over
• CD8-Positive T-Lymphocytes
• Humans
• Interferon-gamma Release Tests
• Latent Tuberculosis
• Tuberculin Test
• Tuberculosis
• Tuberculosis, Pulmonary (diagnosis)