Frequency and Factors of Indeterminate QuantiFERON-TB Gold In-Tube and QuantiFERON-TB Gold PLUS Test Results in Rheumatic Diseases

Abstract

We compared the results and differences of indeterminate rates between the QuantiFERON-TB Gold In-Tube (QFT-GIT) and QuantiFERON-TB Gold PLUS (QFT-PLUS) tests in patients with rheumatic diseases and analyzed the associated factors. Data of patients with rheumatic diseases who had undergone the QFT-GIT or QFT-PLUS test were used, and information regarding patient demographics, primary diagnosis, laboratory results, and medications was collected. Furthermore, indeterminate result rates of the patient cohort and healthy controls were also compared. A total of 177 (43.4%) and 231 (56.6%) patients had undergone QFT-GIT and QFT-PLUS tests, respectively. Among them, four (2.3%) and seven (3.0%) patients had indeterminate results, which did not differ between the QFT-GIT and QFT-PLUS groups. Indeterminate results were significantly higher among patients with rheumatic diseases than in healthy controls (2.7% vs. 0.2%, p < 0.001). Multivariate logistic regression revealed that the lymphocyte count (hazard ratio (HR) 0.998, 95% confidence interval (CI) 0.997, 1.000; p = 0.012) and albumin level (HR 0.366, 95% CI 0.150, 0.890; p = 0.027) were predictive of indeterminate results. A lymphocyte count of ≤810/mm3 and an albumin level of ≤3.7 mg/dL were capable of discriminating between indeterminate and determinate results. The QFT-GIT and QFT-PLUS tests have comparable diagnostic performances in patients with rheumatic diseases. Decreased lymphocyte and albumin levels contribute to indeterminate results.

Comparison of diagnostic accuracy of QuantiFERON‐TB Gold Plus and T‐SPOT.TB in the diagnosis of active tuberculosis in febrile patients

“…As for QFT, in addition to factors associated with the experimental operation, it has been reported that malignancy, lymphopenia, HIV infection, hematologic malignancy, use of immunosuppressive agents, and severe tuberculosis may also be risk factors for ITRS of IGRAs due to the insufficient response to mitogen positive control. [16][17][18] In our study, QFT-Plus ITRS was observed in 8/240 tests (3.3%), 7 out of 8 subjects with QFT-Plus ITRS had diabetes or autoimmune disease and 1 had severe tuberculous pericarditis. ITRS was not observed in T-SPOT.TB in our study.…”

“…Others(16) Drug fever (5) Idiopathic constrictive pericarditis (2) Chronic granulomatous disease (3) Pulmonary embolism (1) Physiological fever (1) Pulmonary alveolus proteinosis (1) Metabolic myopathies (1) Organizing pneumonia (1) Kikuchi-Fujimoto disease (1) F I G U R E 1 Study flow chart TA B L E 3 Demographic characteristics and laboratory examination of the subjected patients Characteristics ATB (n = 80) Non-ATB (n = 160) Microbiologically confirmed (n = 58) Clinical diagnosed (n = 22)…”

Prevalence of indeterminate tuberculosis interferon‐gamma release assays in COVID‐19 patients: Systematic review and meta‐analysis

“…Several immunocompromising conditions, such as HIV infection, 30 advanced liver disease, 31 malnutrition, a low albumin level, 32,33 helminth infection, 34 and corticosteroid use 8,35,36 have been reported to be associated with indeterminate IGRA results.…”

“…Several immunocompromising conditions, such as HIV infection, 30 advanced liver disease, 31 malnutrition, a low albumin level, 32 , 33 helminth infection, 34 and corticosteroid use 8 , 35 , 36 have been reported to be associated with indeterminate IGRA results. Since corticosteroids and other immunosuppressive therapies could be prescribed in COVID‐19 patients, it is plausible to speculate that the elevated rates of indeterminate results may be related to their use.…”

Glucocorticoid use as a cause of non-cellular immune response to SARS-Cov2 Spike in patients with immune system diseases

“…Several parameters were previously demonstrated to influence the T cell response in the IGRA assay [ [13] , [14] , [15] ]. They included PMN and lymphocyte counts, a defective T cell capacity to respond to PHA stimulation (IGRA-PHA), GC dose, and serum albumin level.…”