High two-month mortality in Gabonese adults with and without tuberculosis: A prospective cohort study of patients with presumed pulmonary tuberculosis.

Objectives: Pulmonary tuberculosis (PTB) remains a leading cause of mortality in sub-Saharan Africa but often remains unconfirmed. Patient outcomes in unconfirmed TB or non-TB cases are rarely studied. We assessed 2-month outcomes and associated factors in presumed TB cases independent of TB status. Methods: Hospitalized adults with presumed PTB in Lambaréné, Gabon, were prospectively enrolled (September 2024-January 2025). Demographic data, including a socioeconomic status (SES) score, were collected. Laboratory analyses included HIV-test, GeneXpert and mycobacterial culture. Chest X-rays (CXR) were assessed for signs of TB and non-TB conditions. Diagnoses were categorized as Results: Of 103 participants, 30 of 102 (29%) were HIV positive. Median age was 44 years (interquartile range 28-57). PTB was confirmed in 34 of 103 (33%), clinically diagnosed in 5 of 103 (5%), and not diagnosed in 62 of 103 (62%). In the non-TB group, CXR findings were consistent with bacterial pneumonia (24/62, 39%) or malignancy (12/62, 19%). At follow-up, 81 of 100 (81%) reported improvement, whereas 19 of 100 (19%) did not, including 12 of 100 (12%) deaths. HIV infection, smoking, alcohol use, rural residence, and lower SES were associated with death, no difference was seen by TB status. Conclusion: High 2-month mortality, regardless of final TB status, highlights the need for improved access to diagnostics and better treatment algorithms in severe respiratory illness. Study registry: German Clinical Trials Register (DRKS00034074).