The QuantiFERON-TB Gold test is an interferon-gamma release assay (IGRA) used to detect Mycobacterium tuberculosis infection. A result indicating infection when the individual is not actually infected is termed a false positive. This outcome can occur due to various factors such as laboratory error, recent vaccination with BCG (in some cases), or cross-reactivity with other mycobacterial species. For example, an individual might receive a result suggesting latent tuberculosis infection despite having no actual exposure to the tuberculosis bacteria, leading to unnecessary anxiety and treatment.
Understanding the potential for these erroneous outcomes is crucial for effective tuberculosis control. The possibility influences clinical decision-making, particularly in low-prevalence settings where the likelihood of a true positive result is lower. Historically, relying solely on tuberculin skin tests posed challenges due to its subjectivity and cross-reactivity with BCG. The development of IGRAs like QuantiFERON-TB Gold aimed to improve specificity. However, awareness of the possibility of incorrect positive results remains essential for appropriate test interpretation and patient management.
