[Tuberculin sensitivity in old children with new-onset active tuberculosis]

Area of Science:

• Immunology
• Infectious Diseases
• Pediatrics

Background:

• The tuberculin skin test (TST) is a key tool for diagnosing tuberculosis (TB) infection.
• Recent observations suggest a diminished diagnostic efficacy of the 2 tuberculin units (TE) purified protein derivative (PPD-L) test.
• High rates of tuberculin positivity in certain age groups, like senior pupils and adolescents, pose diagnostic challenges.

Purpose of the Study:

• To investigate the reduced diagnostic value of the 2 TE PPD-L tuberculin test.
• To analyze factors influencing tuberculin sensitivity and their impact on tuberculosis diagnosis in children and adolescents.

Main Methods:

• The study assessed tuberculin test results in senior pupils and adolescents.
• Data analysis focused on the correlation between tuberculin sensitivity and confirmed tuberculosis cases.
• Investigated the influence of factors like contact with infectious individuals, comorbidity, and helminthic invasion on test outcomes.

Main Results:

• Tuberculin diagnosis only indicated suspicion of tuberculosis in 25.9% of senior pupils and 10.7% of adolescents.
• A high prevalence of tuberculin-positive individuals complicates diagnosis, particularly those with monotonous tuberculin sensitivity.
• Contact with infectious individuals did not significantly alter delayed hypersensitivity outcomes.
• Comorbidity and helminthic invasion showed no significant impact on tuberculin sensitivity in this study population.

Conclusions:

• The 2 TE PPD-L tuberculin test exhibits reduced diagnostic value in specific pediatric populations.
• Increased tuberculin positivity and monotonous sensitivity present significant challenges for accurate tuberculosis diagnosis.
• Further research is needed to understand immune system changes, such as those during reactivation, affecting tuberculin test interpretation.