Pneumonia causes significant mortality in intensive care unit (ICU) patients, yet traditional culture-based pathogen detection lacks sufficient sensitivity. While bronchoalveolar lavage fluid (BAL) provides optimal diagnostic yield, bronchoscopy is often contraindicated in critically ill patients. This study compares the respiratory microbiome profiles of paired tracheal aspirate (ETA) and BAL samples from pneumonia patients in a tertiary hospital ICU (n=23, November 2019-September 2022). Using 16S rRNA next-generation sequencing, we analyzed microbial diversity (Shannon Index), taxonomic composition, and differential abundance (edgeR). Results showed comparable diversity indices and microbial communities between ETA and BAL samples, with ETA successfully capturing key pneumonia-related microbial signatures. These findings validate ETA as a reliable, less invasive alternative to BAL for respiratory microbiome analysis in critically ill patients, establishing the groundwork for future clinical applications.

Background: The molecular changes associated with the progression of intraductal papillary mucinous neoplasm (IPMN) to pancreatic ductal adenocarcinoma (PDAC) and distant metastasis remain incompletely understood. Case Presentation: A man in his late 70s underwent pancreaticoduodenectomy and partial hepatectomy for a pancreatic head tumor with synchronous liver metastasis. Histology showed a 4.5 cm moderately differentiated PDAC arising in an IPMN with high-grade dysplasia (pT3N1M1). Genomic analysis of the IPMN, PDAC, and liver metastasis identified KRAS p.G12D, CDKN2A deletion, and GNAS p.R201H in the IPMN; additional SMAD4 p.R361C in the PDAC; and KRAS p.G12D, CDKN2A deletion, SMAD4 p.R361C, and APC p.R1450Ter in the liver metastasis. The APC alteration was confirmed by targeted sequencing and was accompanied by loss of heterozygosity at the APC locus. β-Catenin showed membranous expression in the IPMN and PDAC, but nuclear accumulation in the liver metastasis. Discussion: The shared KRAS, CDKN2A, and SMAD4 alterations support a common clonal origin of the PDAC and metastatic tumors. The absence of a detectable GNAS alteration in the liver metastasis and the presence of a metastasis-specific APC alteration are compatible with, but do not prove, branching evolution and selection of a metastatic subclone. Conclusions: This case shows a metastasis-specific heterozygous APC truncating alteration with loss of heterozygosity, accompanied by nuclear β-catenin accumulation, in an IPMN-associated PDAC.

The crosstalk between immune or alveolar epithelial cells and fibroblasts mediated by paracrine signaling molecules is associated with the pathogenesis of idiopathic pulmonary fibrosis (IPF). However, studies investigating the active involvement of soluble mediators derived from bronchial epithelial cells in fibroblast activation and the development of pulmonary fibrosis are limited. Reanalysis of bulk and single-cell RNA-sequencing data from human bronchus and IPF lung tissue revealed marked upregulation of parathyroid hormone-like hormone (PTHLH) in IPF lung tissue compared with normal tissue, with expression predominantly localized to bronchial epithelial cells. parathyroid hormone-related protein (PTHrP) translated from PTHLH was significantly increased in the bronchial epithelium of IPF patients and bleomycin-induced pulmonary fibrosis mice. Furthermore, the paracrine peptide PTHrP1-34, generated through post-translational processing of PTHrP, was elevated in lung homogenates and bronchoalveolar lavage fluid obtained from fibrotic lungs. Cell- and animal-based experiments showed that PTHrP1-34 activated fibroblasts and extracellular matrix production, resulting in the progression of pulmonary fibrosis. In a preclinical evaluation using a bleomycin-induced pulmonary fibrosis mouse model, attenuating effects against pulmonary fibrosis were observed using neutralizing antibodies, peptides, and gene silencing strategies targeting the PTHrP1-34/parathyroid hormone 1 receptor axis. In conclusion, our results suggest that PTHrP1-34 derived from bronchial epithelial cells is involved in the pathogenesis of IPF and is a promising target for alleviating disease progression.

SARS-CoV-2 infection can lead to severe COVID-19, particularly in elderly individuals and those with compromised immunity. Cellular senescence has been implicated as a key pathogenic mechanism. This study investigated the therapeutic potential of regorafenib, a previously characterized senomorphic drug, for severe COVID-19. SARS-CoV-2 virus-infected K18-hACE2 mice, overexpressing the human ACE2 receptor, exhibited 100% mortality by 10 days post infection. Regorafenib treatment significantly improved survival rates, approximately 43% remaining alive. Mechanistically, regorafenib effectively suppressed type I and II interferon and cytokine signaling. Notably, regorafenib inhibited NLR family pyrin domain containing 3 (NLRP3) inflammasome activation, a key driver of the cytokine storm associated with severe COVID-19. Our findings elucidate the molecular mechanisms underlying therapeutic effects of regorafenib and suggest its potential use as a promising treatment option for severe COVID-19.

Cancer-associated fibroblasts (CAFs) are key components of the tumor microenvironment (TME) that influence cancer progression via extracellular matrix (ECM) remodeling and secretion of growth factors and cytokines. Endothelial-to-mesenchymal transition (EndMT) is emerging as an important axis among the heterogeneous origins of CAFs. This review introduces the diverse methods used to induce EndMT in cancer—mouse tumor models, conditioned-medium treatment, co-culture, targeted gene perturbation, ligand stimulation, exosome exposure, irradiation, viral infection, and three-dimensional (3D) culture systems—and summarizes EndMT cell-type evidence uncovered using transcriptomic and proteomic technologies. Hallmark EndMT features include spindle-like morphology, increased motility, impaired angiogenesis and barrier function, decreased endothelial markers (CD31, VE-cadherin), and increased mesenchymal markers (α-SMA, FN1). Reported mechanisms include signaling via TGF-β, cytoskeletal/mechanical stress, reactive oxygen species, osteopontin, PAI-1, IL-1β, GSK-3β, HSP90α, Tie1, TNF-α, HSBP1, and NOTCH. Cancer-induced EndMT affects tumors and surrounding TME—promoting tumor growth and metastasis, expanding cancer stem cell-like cells, driving macrophage differentiation, and redistributing pericytes—and is closely associated with poor survival and therapy resistance. Finally, we indicate each study’s stance: some frame cancer-induced EndMT as a source of CAFs, whereas others, from an endothelial perspective, emphasize barrier weakening and promotion of metastasis.

Background Bronchiectasis is characterised by impaired mucociliary clearance, leading to persistent mucus accumulation, known as mucus plugging (MP). Myeloperoxidase (MPO) is a key molecule that activates neutrophilic inflammation during bronchiectasis, leading to disease progression. However, whether sputum MPO concentration is an independent factor associated with MP remains unclear. Methods We retrospectively evaluated 78 patients with bronchiectasis at Chungbuk National University Hospital (Cheongju, Republic of Korea) between June 2022 and April 2023. According to the extent of MP on chest computed tomography, participants were divided into high MP (MP in >9 bronchopulmonary segments) and low MP (MP in <= 9 bronchopulmonary segments) groups. We evaluated whether sputum MPO concentration is independently associated with MP using multivariable adjusted logistic regression analyses. Results There were 59 (75.6%) and 19 (24.4%) participants in the low and high MP groups, respectively. Compared with the low MP group, the high MP group had significantly higher disease severity, as measured by the modified Reiff score (p<0.001) and FACED score (p=0.003). Sputum MPO concentration was significantly correlated with the extent of MP (rho=0.313, p=0.009). In addition, sputum MPO concentration was independently associated with a high extent of MP even after adjusting for potential confounders (adjusted OR 1.60 (95% CI 1.06-2.42)). Conclusions Sputum MPO concentration was associated with a high degree of MP, suggesting a potential role of MPO in the pathogenesis of mucus plugging.

BACKGROUND:The molecular pathophysiology underlying the development of bronchiectasis with exacerbation at the proteomic level has not been clarified using bronchoalveolar lavage fluid samples. This study aimed to evaluate the bronchoalveolar lavage fluid inflammatory profiles associated with exacerbation of bronchiectasis. METHODS:We analyzed the bronchoalveolar lavage fluid specimens from 4 patients in the exacerbation status and 4 patients in a stable status using liquid chromatography-tandem mass spectrometry. RESULTS:A total of 1,577 proteins were identified using proteomic analysis, with 127 differentially expressed proteins. Of 127 differentially expressed proteins, 23 proteins showed more than 2-fold differences between exacerbation and stable status groups. The exacerbation status was associated with 18 upregulated proteins (TPI1, CRP, BPI, ORM1, PTPRE, S100A9, BPY2, TPM4, ERVFC1-1, CYS1, CLEC3B, S100A8, PSAT1, NDUFA10, MDGA1, SPRR3, ALDOA, and PSMB2) and five downregulated proteins (MUC5B, HSPE1, KLK13, IGHA1, and MUC5AC). Pathway analysis revealed that the neutrophil degranulation pathway (R-HSA-6798695) was the most enriched pathway in these proteins, followed by the C-type lectin receptor pathway (R-HSA-5621481). CONCLUSION:The bronchoalveolar lavage fluid protein expression in patients in the exacerbation status of bronchiectasis was significantly different from that in patients in the stable status, indicating that neutrophil degranulation and C-type lectin receptor pathways are the most enriched pathways during exacerbation.

Cellular senescence, a hallmark of aging, is pathogenically linked to the development of aging-related diseases. This study demonstrates that FRMD6, an upstream component of the Hippo/YAP signaling cascade, is a key regulator of senescence. Proteomic analysis revealed that FRMD6 is upregulated in senescent IMR90 fibroblasts under various senescence-inducing conditions. Silencing FRMD6 mitigated the senescence of IMR90 cells, suggesting its requirement in senescence. Conversely, the overexpression of FRMD6 alone induced senescence in cells and in lung tissue, establishing a causal link. The elevated FRMD6 levels correlated well with increased levels of the inhibitory phosphorylated YAP/TAZ. We identified cellular communication network factor 3 (CCN3), a key component of the senescence-associated secretory phenotype regulated by YAP, whose administration attenuated FRMD6-induced senescence in a dose-dependent manner. Mechanistically, FRMD6 interacted with and activated MST kinase, which led to YAP/TAZ inactivation. The expression of FRMD6 was regulated by the p53 and SMAD transcription factors in senescent cells. Accordingly, the expression of FRMD6 was upregulated by TGF-β treatment that activates those transcription factors. In TGF-β-treated IMR90 cells, FRMD6 mainly segregated with p21, a senescence marker, but rarely segregated with α-SMA, a myofibroblast marker, which suggests that FRMD6 has a role in directing cells towards senescence. Similarly, in TGF-β-enriched environments, such as fibroblastic foci (FF) from patients with idiopathic pulmonary fibrosis, FRMD6 co-localized with p16 in FF lining cells, while it was rarely detected in α-SMA-positive myofibroblasts that are abundant in FF. In sum, this study identifies FRMD6 as a novel regulator of senescence and elucidates the contribution of the FRMD6-Hippo/YAP-CCN3 axis to senescence.

Understanding the mammalian pathogenesis and interspecies transmission of HPAI H5N8 virus hinges on mapping its adaptive markers. We used deep sequencing to track these markers over five passages in murine lung tissue. Subsequently, we evaluated the growth, selection, and RNA load of eight recombinant viruses with mammalian adaptive markers. By leveraging an integrated non-linear regression model, we quantitatively determined the influence of these markers on growth, adaptation, and RNA expression in mammalian hosts. Furthermore, our findings revealed that the interplay of these markers can lead to synergistic, additive, or antagonistic effects when combined. The elucidation distance method then transformed these results into distinct values, facilitating the derivation of a risk score for each marker. In vivo tests affirmed the accuracy of scores. As more mutations were incorporated, the overall risk score of virus heightened, and the optimal interplay between markers became essential for risk augmentation. Our study provides a robust model to assess risk from adaptive markers of HPAI H5N8, guiding strategies against future influenza threats.

Background The association between inflammatory bowel disease (IBD) and an increased risk of bronchiectasis, as well as contributing factors, remains unclear. Additionally, whether bronchiectasis increases disease burden in IBD remains unknown. Therefore, this study aimed to: 1) assess whether IBD increases the risk of incident bronchiectasis; 2) compare the risk of bronchiectasis between individuals with Crohn's disease (CD) and those with ulcerative colitis (UC); 3) identify risk factors for bronchiectasis in individuals with IBD; and 4) examine the disease burden in individuals with IBD and bronchiectasis versus those without. Methods We conducted a population-based matched cohort study involving adults aged ≥20 years with IBD, using data acquired from the Korean National Health Insurance Service-National Sample Cohort database between 2002 and 2012. Results During the mean follow-up of 9.6 years, the incidence rate of bronchiectasis was 419.63 out of 100 000 person-years (PY) and 309.65 out of 100 000 PY in the IBD and matched cohorts (adjusted hazard ratio (aHR) 1.21, 95% CI 1.05–1.39), respectively. UC was associated with increased bronchiectasis risk (aHR 1.42, 95% CI 1.19–1.69), but CD was not. Multivariate Cox regression analyses showed that age, male sex, medical aid, underweight status, COPD and diabetes mellitus were associated with an increased risk of bronchiectasis in the IBD cohort (p<0.05). The mortality, emergency department visit and hospitalisation rates were significantly higher for individuals with IBD and bronchiectasis compared with those without bronchiectasis (p<0.05). Conclusion IBD is associated with increased risk of bronchiectasis, which results in a greater disease burden in individuals with IBD.

Enteroviruses (EVs) have been associated with several human diseases. Due to their continuous emergence and divergence, EV species have generated more than 100 types and recombinant strains, increasing the public health threat caused by them. Hence, an efficient and universal cloning system for reverse genetics (RG) of highly divergent viruses is needed to understand the molecular mechanisms of viral pathology and evolution. In this study, we generated a versatile human EV whole-genome cDNA template by enhancing the template-switching method and designing universal primers capable of simultaneous cloning and rapid amplification of cDNA ends (RACE)-PCR of EVs. Moreover, by devising strategies to overcome limitations of previous cloning methods, we simplified significant cloning steps to be completed within a day. Of note, we successfully verified our efficient universal cloning system enabling RG of a broad range of human EVs, including EV-A (EV-A71), EV-B (CV-B5, ECHO6, and ECHO30), EV-C (CV-A24), and EV-D (EV-D68), with viral titers and phenotypes comparable to those of their wild types. This rapid and straightforward universal EV cloning strategy will help us elucidate molecular characteristics, pathogenesis, and applications of a broad range of EV serotypes for further development of genetic vaccines and delivery tools using various replication systems. IMPORTANCE Due to the broad spread, incidence, and genetic divergence of enteroviruses (EVs), it has been challenging to deal with this virus that causes severe human diseases, including aseptic meningitis, myocarditis, encephalitis, and poliomyelitis. Therefore, an efficient and universal cloning system for the reverse genetics of highly divergent EVs contributes to an understanding of the viral pathology and molecular mechanisms of evolution. We have simplified the important cloning steps, hereby enhancing the template-switching method and designing universal primers, which enable the important cloning steps to be completed in a day. We have also successfully demonstrated recovery of a broad range of human EVs, including EV-A to -D types, using this advanced universal cloning system. This rapid and robust universal EV cloning strategy will aid in elucidating the molecular characteristics, pathogenesis, and applications of a wide range of EVs for further development of genetic vaccines and antiviral screening using various replication systems.

The Hippo kinase cascade functions as a central hub that relays input from the "outside world" of the cell and translates it into specific cellular responses by regulating the activity of Yes-associated protein 1 (YAP1). How Hippo translates input from the extracellular signals into specific intracellular responses remains unclear. Here, we show that transforming growth factor β (TGFβ)-activated TAK1 activates LATS1/2, which then phosphorylates YAP1. Phosphorylated YAP1 (p-YAP1) associates with RUNX3, but not with TEAD4, to form a TGFβ-stimulated restriction (R)-point-associated complex which activates target chromatin loci in the nucleus. Soon after, p-YAP1 is exported to the cytoplasm. Attenuation of TGFβ signaling results in re-localization of unphosphorylated YAP1 to the nucleus, where it forms a YAP1/TEAD4/SMAD3/AP1/p300 complex. The TGFβ-stimulated spatiotemporal dynamics of YAP1 are abrogated in many cancer cells. These results identify a new pathway that integrates TGFβ signals and the Hippo pathway (TGFβ→TAK1→LATS1/2→YAP1 cascade) with a novel dynamic nuclear role for p-YAP1.

Background: Although poor oral health is a common comorbidity in individuals with airflow limitation (AFL), few studies have comprehensively evaluated this association. Furthermore, the association between oral health and the severity of AFL has not been well elucidated. Methods: Using a population-based nationwide survey, we classified individuals according to the presence or absence of AFL defined as pre-bronchodilator forced expiratory volume in 1 second/forced vital capacity < 0.7. Using multivariable logistic regression analyses, we evaluated the association between AFL severity and the number of remaining teeth; the presence of periodontitis; the Decayed, Missing, and Filled Teeth (DMFT) index; and denture wearing. Results: Among the 31,839 participants, 14% had AFL. Compared with the control group, the AFL group had a higher proportion of periodontitis (88.8% vs. 79.4%), complete denture (6.2% vs. 1.6%), and high DMFT index (37.3% vs. 27.8%) (P < 0.001 for all). In multivariable analyses, denture status: removable partial denture (adjusted odds ratio [aOR], 1.12; 95% confidence interval [95% CI], 1.04-1.20) and complete denture (aOR, 1.52; 95% CI, 1.01- 2.05), high DMFT index (aOR, 1.13; 95% CI, 1.02-1.24), and fewer permanent teeth (0-19; aOR, 1.32; 95% CI, 1.12-1.52) were significantly associated with AFL. Furthermore, those with severe to very severe AFL had a significantly higher proportion of complete denture (aOR, 2.41; 95% CI, 1.11-3.71) and fewer remaining teeth (0-19; aOR, 2.29; 95% CI, 1.57-3.01). Conclusion: Denture wearing, high DMFT index, and fewer permanent teeth are significantly associated with AFL. Furthermore, a reduced number of permanent teeth (0-19) was significantly related to the severity of AFL. Therefore, physicians should pay attention to oral health in managing patients with AFL, such as chronic obstructive pulmonary disease.

Since the first emergence of the SARS-CoV-2 variant in late 2020, novel variants have been continuously introduced to the human population, causing severe public health threats. In general, because these variants acquire new genetic mutation/s, it is critical to analyze the biological function of viruses that such mutations can confer.

Oncogenic K-RAS mutations occur in approximately 25% of human lung cancers and are most frequently found in codon 12 (G12C, G12V, and G12D). Mutated K-RAS inhibitors have shown beneficial results in many patients; however, the inhibitors specifically target K-RASG12C and acquired resistance is a common occurrence. Therefore, new treatments targeting all kinds of oncogenic K-RAS mutations with a durable response are needed. RUNX3 acts as a pioneer factor of the restriction (R)-point, which is critical for the life and death of cells. RUNX3 is inactivated in most K-RAS-activated mouse and human lung cancers. Deletion of mouse lung Runx3 induces adenomas (ADs) and facilitates the development of K-Ras-activated adenocarcinomas (ADCs). In this study, conditional restoration of Runx3 in an established K-Ras-activated mouse lung cancer model regressed both ADs and ADCs and suppressed cancer recurrence, markedly increasing mouse survival. Runx3 restoration suppressed K-Ras-activated lung cancer mainly through Arf-p53 pathway-mediated apoptosis and partly through p53-independent inhibition of proliferation. This study provides in vivo evidence supporting RUNX3 as a therapeutic tool for the treatment of K-RAS-activated lung cancers with a durable response.

Even though the World Health Organization announced the end of the COVID-19 pandemic as a global public health emergency on May 5, 2023, SARS-CoV-2 continues to pose a significant health threat worldwide, resulting in substantial numbers of infections and fatalities. This study investigated the antiviral potential of Z-FA-FMK (FMK), a novel host cathepsin L protease inhibitor, against SARS-CoV-2 infection using both in vitro and in vivo models. In vitro assessments of FMK against a diverse set of SARS-CoV-2 strains, including the Wuhan-like strain and nine variants, demonstrated potent inhibition with EC50 values ranging from 0.55 to 2.41 μM, showcasing similar or superior efficacy compared to FDA-approved antivirals nirmatrelvir (NTV) and molnupiravir (MPV). In vivo experiments using orally administered FMK (25 mg/kg) in SARS-CoV-2-infected K18 hACE2 transgenic mice revealed improved survival rates of 60% and accelerated recovery compared to NTV and MPV treatments. Additionally, FMK displayed a longer half-life (17.26 ± 8.89 h) than NTV and MPV in the mouse model. Due to its host-targeting mechanism, FMK offers potential advantages such as reduced drug resistance and broad-spectrum antiviral activity against multiple coronaviruses. These findings indicate that FMK may serve as a promising candidate for further clinical evaluation in the fight against SARS-CoV-2.

Background Subjects with diabetes are at higher risk of serious influenza-related complications. We aimed to investigate the yearly trend of influenza vaccination and factors associated with being unvaccinated for influenza in subjects with diabetes using a nationwide observational study performed within the recent decade. Methods Among 105,732 subjects from the Korea National Health and Nutrition Examination Survey between 2007 and 2019, 8,632 with diabetes were included. We investigated the yearly trend of influenza vaccination and factors associated with being unvaccinated for influenza. Results During the study period, the prevalence of influenza vaccination in subjects with diabetes showed a tendency to increase every year, reaching almost 60% in 2019, which was higher than the rate in subjects without diabetes. Younger age (adjusted hazard ratio (aHR) [95% CI] 11.29 [8.63–14.75] for < 50 years; 6.16 [5.21–7.29] for 50–65 years), male (aHR 1.67 [1.52–1.87]), current smoker (aHR 1.31 [1.00–1.72], lower-income status (aHR 1.46 [1.17, 1.84]), and high education level (aHR 1.30 [1.01–1.67]) were associated with being unvaccinated. Also, a poorer glycemic control with HbA1c ≥ 9% was found to be correlated with unvaccinated status (aHR 1.48 [1.15–1.90]). Conclusion The influenza vaccination rate is still unsatisfactory in subjects with diabetes. Young age, males, low-income level, high education level, and poor glycemic control were associated with unvaccinated status. Considering the risk-benefits of influenza vaccination in patients with diabetes, physicians should make an effort to increase vaccination rates, especially in low vaccination rate groups.

The ongoing COVID-19 pandemic highlights the urgent need for effective antiviral agents and vaccines. Drug repositioning, which involves modifying existing drugs, offers a promising approach for expediting the development of novel therapeutics. In this study, we developed a new drug, MDB-MDB-601a-NM, by modifying the existing drug nafamostat (NM) with the incorporation of glycyrrhizic acid (GA). We assessed the pharmacokinetic profiles of MDB-601a-NM and nafamostat in Sprague-Dawley rats, revealing rapid clearance of nafamostat and sustained drug concentration of MDB-601a-NM after subcutaneous administration. Single-dose toxicity studies showed potential toxicity and persistent swelling at the injection site with high-dose administration of MDB-601a-NM. Furthermore, we evaluated the efficacy of MDB-601a-NM in protecting against SARS-CoV-2 infection using the K18 hACE-2 transgenic mouse model. Mice treated with 60 mg/kg and 100 mg/kg of MDB-601a-NM exhibited improved protectivity in terms of weight loss and survival rates compared to the nafamostat-treated group. Histopathological analysis revealed dose-dependent improvements in histopathological changes and enhanced inhibitory efficacy in MDB-601a-NM-treated groups. Notably, no viral replication was detected in the brain tissue when mice were treated with 60 mg/kg and 100 mg/kg of MDB-601a-NM. Our developed MDB-601a-NM, a modified Nafamostat with glycyrrhizic acid, shows improved protectivity against SARS-CoV-2 infection. Its sustained drug concentration after subcutaneous administration and dose-dependent improvements makes it a promising therapeutic option.

Abstract Background The association between systemic sclerosis and the development of bronchiectasis is unclear. This study aimed to compare the risk of bronchiectasis between individuals with systemic sclerosis and those without using a nationwide longitudinal dataset. Methods Using the Korean National Health Insurance Service dataset between 2010 and 2017, we identified 4845 individuals aged ≥ 20 years with systemic sclerosis and 24,225 without systemic sclerosis who were matched 1:5 by age and sex. They were followed up until the date of a bronchiectasis diagnosis, death, or December 31, 2019, whichever came first. Results During a median follow-up period of 6.0 (interquartile range, 3.2–8.7) years, 5.3% of the systemic sclerosis cohort and 1.9% of the matched cohort developed bronchiectasis, with incidence rates of 9.99 and 3.23 per 1000 person-years, respectively. Even after adjusting for potential confounders, the risk of incident bronchiectasis was significantly higher in the systemic sclerosis cohort than in the matched cohort (adjusted hazard ratio 2.63, 95% confidence interval 2.22–3.12). A subgroup analysis of individuals with systemic sclerosis revealed that the risk of incident bronchiectasis was notably higher in younger individuals aged 20–39 years (P for interaction = 0.048) and in those without other coexisting connective tissue diseases (P for interaction = 0.006) than in their counterparts. Conclusions The risk of incident bronchiectasis is higher in individuals with systemic sclerosis than those without. Bronchiectasis should be considered one of the pulmonary manifestations related to systemic sclerosis.