Background/Objectives: Tuberculosis (TB) remains a major global public health challenge. In Portugal, TB incidence remains heterogeneous, with higher rates and prolonged diagnostic delays in specific regions. TB-related stigma has been identified as a determinant of delayed diagnosis, barriers to healthcare access, and suboptimal treatment adherence. This study aimed to assess TB related stigma among patients, healthcare professionals, and high-risk contacts; identify factors associated with diagnostic delay; and explore experiences related to stigma in TB context.

Methods: A cross-sectional mixed-methods study was conducted between August and November 2025. The quantitative component included administration of the Tuberculosis Related Stigma Scale (TRSS) to TB patients, high-risk contacts, and healthcare professionals from Community Respiratory Centers of the Tâmega e Sousa Health Unit. Quantitative analyses assessed internal consistency, factor structure, and associations with sociodemographic characteristics and health-related behaviors. The qualitative component consisted of semi-structured questionnaires with open-ended questions applied to patients and healthcare professionals. Thematic analysis was performed to explore perceptions, experiences, and stigma-related factors influencing diagnostic delay and treatment adherence.

Results: The sample comprised 62 patients (mean age 54.3 years; 85.5% male), 75 high-risk contacts (mean age 53.1 years; 62.7% male), and 24 healthcare professionals (mean age 48.6 years; 66.7% female). The TRSS demonstrated good to excellent internal consistency (α = 0.79 in patients; α = 0.85 in contacts; α = 0.93 in professionals), with a factor structure consistent with social distance and avoidance dimensions. Qualitative findings highlighted experiences of stigma and discrimination, fragmented diagnostic pathways, fear of social exposure, barriers to healthcare access, socioeconomic constraints, and unmet psychosocial support needs, contributing to delayed diagnosis and treatment challenges.

Conclusions/Recommendations: TB-related stigma emerged as a cross-cutting determinant influencing timely diagnosis and treatment adherence. The integration of quantitative and qualitative methods enabled a comprehensive understanding of stigma and its epidemiological implications. These findings support the need for TB control strategies that incorporate stigma assessment, targeted health education, professional training, and improved access to care, particularly in high-incidence regions.

Funding: FCT-Fundação para a Ciência e Tecnologia, I.P. projects references UID/4750/2025 and LA/P/0064/2020 DOI identifiers https://doi.org/10.54499/UID/04750/2025 https://doi.org/10.54499/LA/P/0064/2020.