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
Introduction: SARS-CoV-2 caused a pandemic in 2020 with a 'lockdown' resulting in reduced mobility. Activity tracker companies noticed reduced physical activity (PA) in the general population. If observed in patients, this may add to the devastating consequences of physical inactivity. Aim: To investigate PA levels of lung transplant (LTX) recipients before and during the Belgian soft lockdown measures of COVID-19. A decline in daily step count during lockdown measures was hypothesized. Methods: 16 LTX recipients (56% male, mean±SD age 61±6.7 years, 30.2±12.7 months post LTX) involved in an RCT (NCT04122768) were included in the present sub-analysis. Daily step counts were collected by activity trackers, >4 weeks prior to (phase 1) and 4 weeks during the Belgian lockdown (phase 2). The differences in PA between both phases were compared with paired t-tests. Results: Daily number of steps was low in phase 1 (mean±SD 6910±4225 steps/day) but did not change during phase 2 (7016±5665 steps/day), p=0.89, see figure 1. Conclusions: The Belgian COVID-19 lockdown measures did not significantly affect the PA levels of LTX recipients compared to the preceding period.