Kwang-Sook Woo1, Jae-Lim Choi1, Bo-Ram Kim1, Ji-Eun Kim1, Byoung-Gwon Kim2, Hyuck Lee3, Kyeong-Hee Kim4. 1. Department of Laboratory Medicine, Dong-A University College of Medicine, Busan, Republic of Korea. 2. Department of Preventive Medicine, Dong-A University College of Medicine, Busan, Republic of Korea. 3. Department of Internal Medicine, Dong-A University College of Medicine, Busan, Republic of Korea. 4. Department of Laboratory Medicine, Dong-A University College of Medicine, Busan, Republic of Korea. Electronic address: progreen@dau.ac.kr.
Abstract
BACKGROUND: Clinical data of serial interferon-γ release assay (IGRA) testing in routine laboratory practice are limited. IFN-γ response to mitogen is used as a positive control in IGRA. We assessed the association between IFN-γ response to nil, mitogen, tuberculosis (TB) mycobacterial antigens, and the variations from the results of the serial testing. METHOD: A total of 299 patients with serial QuantiFERON-TB Gold In-Tube (QFT-GIT) were enrolled. The medical records of patients were reviewed for demographic information, status of Mycobacterium tuberculosis infection, treatment of tuberculosis, and the quantitative response to nil, mitogen, and TB antigen. RESULTS: The initial QFT-GIT result was positive in 142 patients (47.5%), negative in 139 (46.5%), and indeterminate in 18 (6.0%). Of total, 79.6% showed concordant results in serial testing. The discordance in serial tests was significantly high in patients with a low mitogen response (≤ 3.93 IU/ml) (p<0.0001). Quantitative TB responses around the cut-off point in serial QFT-GIT were associated with an increased conversion and reversion rates (p = 0.01, p = 0.0005), respectively. CONCLUSION: Because IGRAs are dynamic assays, integrated interpretation of quantitative TB response with mitogen and nil response would be helpful in serial QFT-GIT. Recommendations for the interpretation of results of serial testing for active TB will be required.
BACKGROUND: Clinical data of serial interferon-γ release assay (IGRA) testing in routine laboratory practice are limited. IFN-γ response to mitogen is used as a positive control in IGRA. We assessed the association between IFN-γ response to nil, mitogen, tuberculosis (TB) mycobacterial antigens, and the variations from the results of the serial testing. METHOD: A total of 299 patients with serial QuantiFERON-TB Gold In-Tube (QFT-GIT) were enrolled. The medical records of patients were reviewed for demographic information, status of Mycobacterium tuberculosis infection, treatment of tuberculosis, and the quantitative response to nil, mitogen, and TB antigen. RESULTS: The initial QFT-GIT result was positive in 142 patients (47.5%), negative in 139 (46.5%), and indeterminate in 18 (6.0%). Of total, 79.6% showed concordant results in serial testing. The discordance in serial tests was significantly high in patients with a low mitogen response (≤ 3.93 IU/ml) (p<0.0001). Quantitative TB responses around the cut-off point in serial QFT-GIT were associated with an increased conversion and reversion rates (p = 0.01, p = 0.0005), respectively. CONCLUSION: Because IGRAs are dynamic assays, integrated interpretation of quantitative TB response with mitogen and nil response would be helpful in serial QFT-GIT. Recommendations for the interpretation of results of serial testing for active TB will be required.
Authors: Joel Monárrez-Espino; José Antonio Enciso-Moreno; Lucie Laflamme; Carmen J Serrano Journal: Mem Inst Oswaldo Cruz Date: 2014-11 Impact factor: 2.743
Authors: Vanessa Lucília Silveira de Medeiros; Fabiana Cristina Fulco Santos; Lílian Maria Lapa Montenegro; Maria da Conceição Silva; Valdênia Maria Oliveira de Souza; Reginaldo Gonçalvez de Lima Neto; Líbia Cristina Rocha Vilela Moura; Vera Magalhães Journal: PLoS One Date: 2020-12-03 Impact factor: 3.240