[Epidemiology of tuberculosis]

To analyze the current epidemiological trend of childhood tuberculosis in Spain.

The annual reports from Tuberculosis and Respiratory Infections Group of the Spanish Society of Respiratory Disease and from the Multicenter Project for Tuberculosis Research Study Group (1996-1997) were used. The "mirror technique" was applied to detect interference in the interpretation of the tuberculin skin test in a tuberculin survey carried out in 51,877 schoolchildren (aged 418 years). The sensitivity, specificity, positive predictive value and negative predictive value of the test were evaluated.

The incidence rate in 13 Autonomous Communities was 12.79 per 100,000 inhabitants. In 1998 the prevalence of this infection was 0.53% at 6 years and 4.7% at 14 years. A cutoff point of 13 mm showed the highest sensitivity, specificity, positive predictive value and negative predictive value.

The trend in childhood tuberculosis during the last few years has been favorable. Interference by nontuberculous mycobacterial infection in the prevalence of the tuberculin skin test was detected. Consequently, use of the American Thoracic Society's guidelines for the interpretation of the tuberculin skin test, with some modifications, is recommended.