Latent Tuberculosis Infection

This retrospective observational single-center study aims to evaluate the medical and occupational relevance of systematic screening for latent tuberculosis infection using QuantiFERON-TB Gold Plus during pre-employment occupational health assessment among hospital workers at the University Hospital of Nice. Data will be collected retrospectively from occupational health medical records, immunology laboratory results and, when necessary, data from specialized follow-up by the tuberculosis control center. The primary objective is to determine the proportion of positive QuantiFERON-TB Gold Plus tests at pre-employment screening. Secondary objectives are to identify factors associated with a positive test, to describe the practical consequences of screening, including chest X-ray, diagnosis of latent tuberculosis infection and initiation of preventive treatment, and to estimate the cost of systematic screening.

This observational cross-sectional study aims to determine the prevalence of latent tuberculosis infection (LTBI) among patients undergoing regular hemodialysis at Sohag University Hospital, using the tuberculin skin test (TST). Identifying the burden of LTBI in this high-risk population will help guide early detection and preventive strategies

The goal of this observational study is to investigate the proportion of Mycobacterium tuberculosis (MTB) infection in school contacts of active tuberculosis (ATB) patients. The main questions it aims to answer are: * the proportion of MTB infection among school contacts of ATB patients * risk factors related to tuberculosis (TB) infection * health economic evaluation of screening strategy