[Tuberculosis surveillance in the Balearic Islands and characteristics of unreported cases from 2005 to 2007].

We performed a descriptive study of tuberculosis cases detected by the Epidemiological Surveillance System in the Balearic Islands in the triennium 2005-2007. Our goal was to characterize underreported cases in sociodemographic terms and their contact with primary care. Overall, underreporting of tuberculosis was approximately 20%. Significant factors in multivariate analysis were social marginality (consisting of alcoholism, intravenous drug use or indigence) (aOR: 2.6 [1.2 to 5.3]), contact with primary care (aOR: 3.2 [1.4 to 7.1]), and extrapulmonary tuberculosis (aOR: 5.5[3.2-9.6]). We recommend strengthening notification by hospital specialists through the use of hospital electronic records. Our findings show that the information obtained from the primary care computerized history is helpful in improving the epidemiological surveillance of tuberculosis.