Bronchiectasis is associated with lower lung function in lung cancer screening participants.

BACKGROUND AND OBJECTIVE: Bronchiectasis is a frequent incidental finding on chest computed tomography (CT), but its relevance in lung cancer screening is not fully understood. We investigated the association between bronchiectasis and respiratory symptoms, pulmonary function, and emphysema in lung cancer screening participants with and without chronic obstructive pulmonary disease (COPD). METHODS: We included 3260 (ex-)smokers from the Dutch-Belgian lung cancer screening trial (NELSON). Bronchiectasis was scored by chest radiologists. The relationship with pulmonary function (FEV1%predicted, FEV1/FVC), respiratory complaints (cough, dyspnea, wheezing, mucus hypersecretion), and CT-quantified emphysema (15th percentile) was examined with independent t-tests and multivariate regression. RESULTS: Bronchiectasis was present in 5.4% (n = 175/3260). There was no difference in prevalence between subjects with and without COPD (68/1121 [5.9%] vs. 109/2139 [5.1%]; p = .368). COPD subjects with bronchiectasis had a lower FEV1%predicted (76.2% vs. 85.0%; p < .001), lower FEV1/FVC (0.58 vs. 0.62; p < .001), and more emphysema (- 938 HU vs. - 930 HU; p = .001) than COPD subjects without bronchiectasis. In COPD subjects, bronchiectasis was independently associated with a lower FEV1%predicted (B = - 7.7; CI [- 12.3, - 3.3]), lower FEV1/FVC (B = - 2.5; CI [- 4.3, - 0.8]), more cough (OR 2.4; CI [1.3, 4.3]), more mucus hypersecretion (OR 1.8; CI [1.0, 3.1]) and more dyspnea (OR 2.3; CI [1.3, 3.9]). In those without COPD (n = 2139), bronchiectasis was associated with more cough, mucus hypersecretion, and wheezing, but not with deteriorating lung function. CONCLUSION: Bronchiectasis was present in 5.4% of our lung cancer screening participants and was associated with more respiratory symptoms and, in those with COPD, with lower lung function and more emphysema. CLINICAL RELEVANCE STATEMENT: In a lung cancer screening population, bronchiectasis has a prevalence of 5.4% with a mainly mild severity. This finding is of little clinical relevance unless mild COPD is also present. In those subjects, bronchiectasis was associated with a lower lung function, more respiratory symptoms, and more emphysema. KEY POINTS: • Bronchiectasis was found in 5.4% of lung cancer screening participants, consisting of (ex-)smokers with and without mild COPD. • In those with mild COPD, bronchiectasis was associated with a lower lung function, more respiratory symptoms, and more emphysema. • Incidental findings of mild bronchiectasis are not very relevant in a lung cancer screening population, unless COPD is also present.

Mimicking fat grafting of fibrotic scars using 3D-organotypic skin cultures.

Wound healing of deep burn injuries is often accompanied by severe scarring, such as hypertrophic scar (HTS) formation. In severe burn wounds, where the subcutis is also damaged, the scars adhere to structures underneath, resulting in stiffness of the scar and impaired motion. Over the recent years, a promising solution has emerged: autologous fat grafting, also known as lipofilling. Previous clinical reports have shown that the anti-fibrotic effect has been attributed to the presence of adipose-derived stromal cells (ADSC). In the proposed study, we aim to investigate the effect of fat grafting in 3D organotypic skin cultures mimicking an HTS-like environment. To this end, organotypic skin cultures were embedded with normal skin fibroblasts (NF) or HTS-derived fibroblasts with or without incorporation of human adipose subcutaneous tissue (ADT) and one part was thermally wounded to examine their effect on epithelialization. The developed skin cultures were analysed on morphology and protein level. Analysis revealed that ADT-containing organotypic skin cultures comprise an improved epidermal homeostasis, and a fully formed basement membrane, similar to native human skin (NHS). Furthermore, the addition of ADT significantly reduced myofibroblast presence, which indicates its anti-fibrotic effect. Finally, re-epithelialization measurements showed that ADT reduced re-epithelialization in skin cultures embedded with NFs, whereas HTS-fibroblast-embedded skin cultures showed complete wound closure. In conclusion, we succeeded in developing a 3D organotypic HTS-skin model incorporated with subcutaneous tissue that allows further investigation on the molecular mechanism of fat grafting.

A Systematic Review of Chest Imaging Findings in Long COVID Patients.

Long COVID is the persistence of one or more COVID-19 symptoms after the initial viral infection, and there is evidence supporting its association with lung damage. In this systematic review, we provide an overview of lung imaging and its findings in long COVID patients. A PubMed search was performed on 29 September 2021, for English language studies in which lung imaging was performed in adults suffering from long COVID. Two independent researchers extracted the data. Our search identified 3130 articles, of which 31, representing the imaging findings of 342 long COVID patients, were retained. The most common imaging modality used was computed tomography (CT) (N = 249). A total of 29 different imaging findings were reported, which were broadly categorized into interstitial (fibrotic), pleural, airway, and other parenchymal abnormalities. A direct comparison between cases, in terms of residual lesions, was available for 148 patients, of whom 66 (44.6%) had normal CT findings. Although respiratory symptoms belong to the most common symptoms in long COVID patients, this is not necessarily linked to radiologically detectable lung damage. Therefore, more research is needed on the role of the various types of lung (and other organ) damage which may or may not occur in long COVID.