INTRODUCTION One of the most recent scoring systems, quick-Sequential Organ Failure Assessment (qSOFA), shows lack of sensitivity as outcome predictor in various clinical settings including thoracic empyema. We aimed to evaluate our new prognostic score Lactate Dehydrogenase-qSOFA (LDH-qSOFA) as a better predictor of death than qSOFA alone, in patients with empyema. METHODS This single-center retrospective study, of 84 patients with thoracic empyema, was conducted in the Clinic of Thoracic Surgery of the University Hospital at Stara Zagora, for the period January 2021-October 2023. LDH levels, SIRS and qSOFA were assessed at admission. We analyzed area under receiver operating characteristics (AUROC) curves of SIRS, qSOFA and LDH-qSOFA, and performed a comparison of their prognostic performance. RESULTS Of the total of 84 patients, nine (10.7%) died during hospitalization. The new LDH-qSOFA score showed the best prognostic ability in comparison to qSOFA alone (AUROC=0.851 vs 0.747) and SIRS (AUROC=0.851 vs 0.676). As predictor of fatal outcome LDH-qSOFA at optimal threshold ≥2 points was observed with higher sensitivity compared to qSOFA ≥2 (62.5% vs 44.4%). CONCLUSIONS In patients with thoracic empyema a combination of qSOFA and LDH demonstrated better prognostic performance than qSOFA alone.