Given the high rate of tuberculosis in the Île-de-France region and the lack of recent epidemiological data on this disease in prisons, the Interregional Epidemiology Unit conducted a study with several objectives: - to measure the prevalence of tuberculosis among the prison population in the Île-de-France region; - to examine the characteristics of tuberculosis cases, their management, and the prevention of secondary cases; - to evaluate screening of inmates arriving from the community. A prospective study was conducted over one year, from July 1, 2005, to June 30, 2006, in the region’s nine pretrial detention centers. The study population consisted of all inmates admitted during the study period, whether from the general community or from another pretrial detention center. For each tuberculosis case agreeing to participate in the study, a questionnaire was completed by physicians from the prison’s Outpatient Consultation and Care Unit (UCSA). The prevalence of tuberculosis among the incoming prison population—whether from the general population or following a transfer—was calculated. To evaluate screening, a questionnaire on general organization was completed by the physicians responsible for screening in each of the pretrial detention centers, and an assessment of the comprehensiveness and timing of screening was conducted. In total, 26 cases of tuberculosis were identified across all pretrial detention centers in the Île-de-France region during the study period. These cases were predominantly young men, often born outside France and in precarious circumstances prior to incarceration. Management of the disease was satisfactory during incarceration, but follow-up of cases and continuation of treatment after release were very difficult. The overall prevalence of tuberculosis in the incoming population was estimated at 106.9 cases of tuberculosis per 100,000 inmates, with significant disparities among detention centers (ranging from 0 to 230.3 per 100,000). Compared to data from a study conducted in 1994–1995 by the Île-de-France Regional Health Observatory, the incidence of tuberculosis in the prison population of the region’s pretrial detention centers was declining, but it remained higher than that in the general population and close to that observed in the most affected segments of the population. Screening procedures varied from one pretrial detention center to another. The average screening rate was 89% for all pretrial detention centers over the study period (ranging from 58% to 99% depending on the center). Only 53% of screened inmates (ranging from 0% to 96%) were screened within the regulatory timeframe (8 days or less between incarceration and the screening result). In conclusion, it is imperative to develop tailored strategies involving prison medical teams, tuberculosis control centers, and potentially social workers to improve medical care for released inmates with tuberculosis. This coordination should begin before the individuals are released. It is also necessary to strengthen resources to improve the comprehensiveness and timeliness of screening, and/or to consider new strategies, such as those recommended by the U.S. Centers for Disease Control and Prevention, which advocate identifying individuals at highest risk for tuberculosis during an initial medical examination and conducting screening only for these individuals. (R.A.)