ABSTRACT
Besides parenchymal changes that have been described extensively in COVID-19, bronchiectasis is also reported but detailed characterization of airway changes is lacking. Hence, we aimed to quantify the number of visible airways and their diameters in end-stage COVID-19 lungs. Explanted right lungs, obtained after lung transplantation (n=2) or autopsy (n=1) (65.3+/-26.7 days after symptom onset), were inflated to total lung capacity, frozen and scanned with whole lung microCT (155 mum). Airways were segmented using Mimics Innovation Suite (Materialise, Belgium) and airway count and diameter were assessed using Neuronstudio. Three discarded donor lungs were used as controls. Number of visible airways increased in COVID-19 lungs compared to controls (fig.1a) potentially caused by airway remodeling and bronchiectasis (fig.1b, red arrows) due to fibrotic rearrangement (fig. 1b). Small airway count (diameter 0-2 mm) in generation (G) 1-11 was lower in COVID-19 patients compared to controls, with a shift of small airways from lower generations (G1-11) to higher generations (G12-27) in COVID-19 patients. Simultaneously, airways with a diameter > 2 mm were increased in all generations in COVID-19 (present until G21 compared to G13 in controls). This study shows that COVID-19 causes a remodeling of the (small) airways, leading to an increase of visible airways and diameter of large and small airways, similar to that seen in idiopathic pulmonary fibrosis due to traction bronchiectasis. (Figure Presented).
ABSTRACT
Background/Introduction: Thromboinflammation in severe COVID-19 is associated with disease severity and outcome. The kallikrein pathway is suggested to mediate thromboinflammation in COVID-19 by activating inflammatory pathways and contactmediated coagulation. Purpose(s): The DAWn-antico study investigates if a multitarget modulation of the thromboinflammatory response improves outcomes in hospitalized patients with severe COVID-19. Method(s): In this multicenter open-label randomized clinical trial (EudraCT 2020-001739-28), patients hospitalized with COVID- 19 were 1:2 randomized to receive standard of care (SOC) or SOC plus study intervention. The intervention consisted of aprotinin (2,000,000 IE IV four times daily) combined with low-molecular-weight heparin (LMWH;SC 50 IU/kg twice daily at the ward, 75 IU/kg twice daily at intensive care). Additionally, patients with predefined hyperinflammation received the interleukin-1- receptor antagonist anakinra (100mg IV four times daily). The primary outcome was time to a sustained 2-point improvement on the 7-point WHO ordinal scale for clinical status, or discharge. The trial was funded by Life Sciences Research Partners, Research Foundation Flanders (G0G4720N), and KU Leuven COVID-19 fund. Result(s): Between 24 June 2020 and 01 February 2021, 105 patients were randomized, and 102 patients were included in the full analysis set (intervention N=67 vs. SOC N=35). Twenty-five patients from the intervention group (37%) received anakinra. The intervention did not affect the primary outcome (HR 0.77 [CI 0.50;1.19], p=0.24) or mortality (intervention n=3 (4.6%) vs. SOC n=2 (5.7%), HR 0.82, [CI 0.14;4.94], p=0.83). There was one treatment-related adverse event in the intervention group (hematuria, 1.49%). There was one thrombotic event in the intervention group (1.49%) and one in the SOC group (2.86%), but no major bleedings. Conclusion(s): In hospitalized COVID-19 patients, modulation of thromboinflammation with high-dose aprotinin and LMWH with or without anakinra did not improve outcome in patients with moderate to severe COVID-19. (Disclosure: this RCT was presented at ISTH 2022 in London and will be published in Research and Practise in Thrombosis and Haemostasis).