Increased Association of Pulmonary Thromboembolism and Tuberculosis during COVID-19 Pandemic: Data from an Italian Infectious Disease Referral Hospital.

Pulmonary thromboembolism (PTE) has been associated with tuberculosis (TB), but the true incidence is unknown. The aim of our study was to retrospectively evaluate the PTE prevalence in TB patients hospitalized at the National Institute for Infectious Diseases L. Spallanzani during the January 2016-December 2021 period. Retrospective data collection and evaluation were conducted. Among 1801 TB patients, 29 (1.61%) exhibited PTE. Twenty (69%) had comorbidities; eleven (37.9%) had predisposing factors for PTE. Nineteen (65.5%) had extensive TB disease. The commonest respiratory symptoms were cough (37.9%), dyspnea (31%), chest pain (10.3%), and hemoptysis (6.9%). Twenty-five (86.2%) had elevated serum D-dimer levels. An increased prevalence of PTE from 0.6% in the pre-COVID-19 pandemic period to 4.6% in the pandemic period was found. Acute respiratory failure and extensive TB disease increased significantly in the pandemic period. The increase in PTE could be explained by the increased severity of TB in patients in the pandemic period and by increased clinical suspicion and, consequently, increased requests for D-dimer testing, including in patients with non-COVID-19 pneumonia. Patients with extensive pulmonary disease are at high risk of developing PTE. Clinicians should be aware of this potentially life-threatening complication of TB, and patients should receive a thromboembolism risk assessment.