QuantiFERON-TB Gold Plus Performance in Children: A Narrative Review

Area of Science:

• Infectious Diseases
• Pediatric Medicine
• Immunology

Background:

• Tuberculosis (TB) diagnosis in children presents unique challenges, particularly in distinguishing latent infection from active disease.
• Interferon-gamma release assays (IGRAs) like QuantiFERON-TB Gold Plus (QFT-Plus) are increasingly used, but their performance in pediatric populations requires thorough evaluation.
• The Bacillus Calmette-Guérin (BCG) vaccination and age can impact the accuracy of traditional diagnostic methods like the tuberculin skin test (TST).

Approach:

• A comprehensive literature search was conducted across PubMed, MEDLINE, and Embase databases from January 2017 to December 2021.
• Studies focusing on the performance of QFT-Plus for diagnosing Mycobacterium tuberculosis (Mtb) infection in children (≤18 years) were selected.
• A total of 14 studies involving 4646 subjects were analyzed, including children with Mtb infection, TB disease, and healthy children with TB contacts.

Key Points:

• Agreement between QFT-Plus and TST in children varied significantly, with kappa values ranging from -0.201 (no agreement) to 0.83 (almost perfect agreement).
• QFT-Plus demonstrated a sensitivity of 54.5%-87.3% for microbiologically confirmed TB disease, with no significant age-related differences observed in children under or over five years old.
• The rate of indeterminate QFT-Plus results in individuals ≤18 years was 0%-33.3%, with a lower rate of 2.6% reported in children under two years old.

Conclusions:

• QFT-Plus exhibits variable concordance with TST in pediatric populations, suggesting careful interpretation is needed.
• The QFT-Plus assay shows promising sensitivity for detecting TB disease in children, irrespective of age.
• IGRAs, including QFT-Plus, may offer a valuable alternative to TST, potentially overcoming limitations associated with BCG vaccination and age in young children.