Features of indeterminate results of QuantiFERON-TB Gold In-Tube test in patients with haematological malignancies

Chen-Cheng Huang; Chieh-Lin Jerry Teng; Ming-Feng Wu; Ching-Hsiao Lee; Hui-Chen Chen; Wei-Chang Huang

doi:10.1177/20406207211028437

Features of indeterminate results of QuantiFERON-TB Gold In-Tube test in patients with haematological malignancies

Ther Adv Hematol. 2021 Jul 6:12:20406207211028437. doi: 10.1177/20406207211028437. eCollection 2021.

Authors

Chen-Cheng Huang¹, Chieh-Lin Jerry Teng², Ming-Feng Wu³, Ching-Hsiao Lee⁴, Hui-Chen Chen³, Wei-Chang Huang⁵

Affiliations

¹ Institute of Molecular Biology, College of Life Sciences, National Chung Hsing University, Taichung.
² Division of Haematology/Medical Oncology, Department of Medicine, Taichung Veterans General Hospital.
³ Division of Chest Medicine, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung.
⁴ Department of Medical Technology, Jen-Teh Junior College of Medicine, Nursing and Management, Miaoli.
⁵ School of Medicine, Chung Shan Medical University, Taichung.

Abstract

Background and aims: The application of QuantiFERON-TB Gold in-Tube (QFT-GIT) in patients with haematological malignancies (HMs) has not been well studied. Therefore, we aimed to investigate the features of patients with HMs whose QFT-GIT results were indeterminate.

Methods: This study enrolled patients with HMs for the analysis of QFT-GIT tests and additional 2-year follow-up. The characteristics and predictors of QFT-GIT indeterminate results were identified. Mycobacterium tuberculosis (TB) incidence rate (IR) and incidence rate ratio (IRR) were also investigated.

Results: Of 89 participants, 27 (30.3%) had QFT-GIT indeterminate results. The QFT-GIT indeterminate patients were characterized with the diagnosis of leukaemia (63.0% versus 32.3%, p = 0.044), abnormal white blood count (WBC) (88.9% versus 14.5%, p = 0.001), abnormal lymphocyte percentage (81.5% versus 14.5%, p = 0.001) and lower lymphocyte count (×10⁹/l) (0.5 versus 2.2, p = 0.000) when compared with those with determinate results. Meanwhile, abnormal WBC [odds ratios (OR): 15.18, p = 0.003] and lymphocyte percentage (OR: 6.90, p = 0.033) were predictors of indeterminate results. One patient with the QFT-GIT indeterminate status and high interferon-γ level of negative control result developed active TB with a TB IR of 18.5 per 1000 person-years and an IRR of 0.1 (95% confidence interval, 0.01-0.71) when compared with positive QFT-GIT patients without prophylaxis treatment.

Conclusion: Abnormal ranges of WBC and lymphocyte differential count percentage were independent predictors useful to determine the optimal timing of implementing QFT-GIT test in patients with HMs.

Keywords: QuantiFERON-TB Gold in-Tube; haematological malignancy; indeterminate.