Symptomatic (STB) and Asymptomatic (ATB) tuberculosis in Italy: Results from a multicenter retrospective study

Objective: Asymptomatic tuberculosis (ATB) represents a significant proportion of tuberculosis (TB) cases. This study aimed to compare ATB and symptomatic TB (STB) cases in terms of demographic and clinical characteristics, adverse events, hospital length of stay, and treatment outcomes. Methods: This multicenter retrospective study included 510 microbiologically confirmed pulmonary TB patients across ten Italian hospitals between 2018 and 2023. STB cases presented with at least one symptom such as cough, fever, chest pain, hemoptysis, dyspnea, night sweats or weight loss. ATB cases presented with no symptoms. The endpoints included adverse events, length of hospital stay, and incompleteness of the treatment. Results: ATB accounted for 36.4 % of cases (184/510). STB was significantly associated with diabetes (p = 0.03), hepatitis B/C infections (p < 0.0001), and history of TB (p = 0.01). Adjusting for clinically relevant confounders, STB was associated with higher occurrence of adverse events (odds ratio 2.04, 95 % confidence interval 1.31 to 3.23; p = 0.002), more severe adverse events (odds ratio 8.07, 95 % confidence interval 2.58 to 33.34; p = 0.001) and a 24 % increase in length of hospital stay (95 % confidence interval 7 % to 47 %; p = 0.005), but was not associated with incomplete treatment (odds ratio 0.79, 95 % confidence interval 0.47 to 1.32; p = 0.37). Conclusions: STB is associated with a higher burden of adverse events. ATB poses challenges for TB elimination due to its asymptomatic nature.