The risk factor of false‐negative and false‐positive for T‐SPOT.TB in active tuberculosis

• Published in: Journal of clinical laboratory analysis Vol. 32; no. 2
• Main Authors: Di, Li, Li, Yan
• Format: Journal Article
• Language: English
• Published: United States John Wiley & Sons, Inc 01.02.2018; John Wiley and Sons Inc
• Subjects: Adult; diagnosis; Diagnostic Errors - statistics & numerical data; Female; Humans; Interferon-gamma Release Tests - methods; Interferon-gamma Release Tests - statistics & numerical data; Male; Meningitis; Middle Aged; Morbidity; risk factor; Risk factors; Smoke; Tuberculosis; Tuberculosis - diagnosis; T‐SPOT; diagnosis; T-SPOT; risk factor; TB; tuberculosis
• ISSN: 0887-8013; 1098-2825; 1098-2825
• DOI: 10.1002/jcla.22273

Objectives T‐SPOT.TB is a promising diagnosis tool to identify both pulmonary tuberculosis and extrapulmonary tuberculosis, as well as latent tuberculosis; however, the factors that affect the results of T‐SPOT.TB remains unclear. In this study, we aim to figure out the risk factor of T‐SPOT.TB for active TB. Methods A total of 349 patients were recruited between January 1st, 2016 and January 22st, 2017 at Renmin Hospital of Wuhan University, including 98 subjects with TB and 251 subjects with non‐TB disease, and received T‐SPOT.TB (Oxford Immunotec Ltd). Statistics were analyzed by SPSS 19.0 using logistic regression. Results The overall specificity and sensitivity of the T‐SPOT.TB was 92.83% (233/251; 95%CI 0.8872‐0.9557) and 83.67% (82/98; 95%CI 0.7454‐0.9010), respectively. Patients with tuberculous meningitis were more likely to have false‐negative results (OR 17.4, 95%CI 3.068‐98.671; P<.001) while patients with cured TB tended to induce false‐positive results (OR 30.297; 95%CI 7.069‐129.849; P<.001). The results were not affected by sex, age, onset time, smoke, alcohol, treatment, allergic history, co‐morbidity, TB (exclude tuberculous meningitis) (P>.05). Conclusion Tuberculous meningitis was a risk factor of false‐negative for T‐SPOT.TB, while cured TB was a risk factor of false‐positive.