Bronchiectasis not due to cystic fibrosis

Bronchiectasis is a clinical-radiological condition composed of irreversible bronchial dilation due to inflammation and infection of the airways, which causes respiratory symptoms, usually productive cough and infectious exacerbations. Bronchiectasis can have multiple causes, both pulmonary and extrapulmonary, and its clinical presentation is very heterogenous. Its prevalence is unknown, although up to 35-50% of severe COPD and 25% of severe asthma present them, so their underdiagnosis is evident. Chronic bacterial bronchial infection is common, and Pseudomonas aeruginosa is the pathogen that has been found to imply a worse prognosis. Treatment of bronchiectasis has three fundamental characteristics: it must be multidisciplinary (involvement of several specialties), pyramidal (from primary care to the most specialized units) and multidimensional (management of all aspects that make up the disease).

Changes in sleep-disordered breathing from the acute to the stable phase of pulmonary embolism: The ESAET study

BACKGROUND

/Objective: Sleep-disordered breathing (SDB) may change from the acute to stable phase of some cardiovascular disorders, but little is known whether these dynamic changes also exist in pulmonary embolism (PE). This study aimed to analyze the changes in the apnea-hypopnea index (AHI) from the acute to stable phase of PE as well as the factors associated.

PATIENTS/METHODS

We conducted a prospective, longitudinal and multicenter study of consecutive adults requiring hospitalization for non-hypotensive acute PE, with a protocol including clinical, imaging (transthoracic echocardiography [TTE] and computed tomography), blood tests and a sleep study within 48 h of diagnosis of PE. After 3 months of follow-up, the sleep study was repeated. Right ventricular (RV) dysfunction was defined according to TTE criteria.

RESULTS

One hundred and eleven patients (mean age [SD]: 63 [15] years; body mass index: 28.4 [4.7] kg/m2) were included. The initial AHI was 24.4 (21.8) events/h (AHI≥5: 82.8 %; AHI≥30: 33.3 %). Seventy-seven patients (69.4 %) had RV dysfunction. In the overall cohort, the AHI decreased by 8.7 events/h from the acute to stable phase (24.4/h vs. 15.7/h; p=0.013). Patients with RV dysfunction showed a greater decrease in AHI (mean decrease 12.3/h vs. 0.43/h). In the multivariable analysis a drop of an AHI≥5 events/hour was independently associated with the presence of initial RV dysfunction (hazard ratio 3.9; 95%CI 1.3 to 12.1).

CONCLUSIONS

In hemodynamically stable patients with acute PE, there is a transient but clinically significant decrease in the AHI from the acute to stable phase, particularly when initially presenting with RV dysfunction.

Etiology of Bronchiectasis in the World: Data from the Published National and International Registries

Bronchiectasis is the third leading chronic inflammatory disease of the airway caused by dozens of pulmonary and extra-pulmonary diseases. Infection by pathogenic microorganisms is very common. We aimed to analyze, for the first time in the literature, the etiology of bronchiectasis throughout the world via data published in national and international registries. A bibliographic search was carried out in PubMed and Web of Science. Seven studies were included, with a total of 27,258 patients from 33 countries of four continents. The most frequent cause of bronchiectasis was post-infectious: 30.5% (range: 19.1-40.4%), followed by idiopathic: 28.7% (18.5-38.1%). Post-tuberculous bronchiectasis accounted for 14.1% (1.8-35.5%), while etiologies associated with COPD and asthma comprised 7% (3.4-10.9%) and 5.2% (2.5-7.8%). In conclusion, there was a high degree of heterogeneity in the relative percentages of the main causes of bronchiectasis in the world, although post-infectious and idiophatic bronchiectasis continue to be the most frequent causes.

The U-Shaped Relationship Between Eosinophil Count and Bronchiectasis Severity: The Effect of Inhaled Corticosteroids

BACKGROUND

Although a proven relationship exists between the blood eosinophil count (BEC) and the severity of both asthma and COPD, its relationship with bronchiectasis has not been well established. The objective of this study was to analyze the relationship between BEC and the number and severity of exacerbations, and patients' responses to inhaled corticosteroid (IC) treatment in bronchiectasis RESEARCH QUESTION: Does an association exist among BEC, the number of exacerbations and severity of bronchiectasis, and IC treatment?

STUDY DESIGN AND METHODS

This was a multicenter (43 centers) prospective observational study derived from the Spanish Bronchiectasis Registry. Patients with proven bronchiectasis and a known BEC were included, whereas those with asthma or antieosinophilic treatments were excluded. Patients were divided into four groups according to the BEC at the time of inclusion in the study in a steady-state situation: (1) eosinopenic bronchiectasis (< 50 eosinophils/μL), (2) low number of eosinophils (51-100/μL), (3) normal number of eosinophils (101-300/μL), and (4) eosinophilic bronchiectasis (> 300 eosinophils/μL).

RESULTS

Nine hundred twenty-eight patients finally were included: 123 patients (13.3%) with < 50 eosinophils/μL (eosinopenic group), 164 patients (17.7%) with 50-100 eosinophils/μL, 488 patients (52.6%) with 101-300 eosinophils/μL, and 153 patients (16.5%) with > 300 eosinophils/μL (eosinophilic group). BEC showed a significant U-shaped relationship with severity, exacerbations, lung function, microbiologic profile, and IC treatment (these being higher in the eosinopenic group compared with the eosinophilic group). IC treatment significantly decreased the number and severity of exacerbations only in the group of bronchiectasis patients with > 300 eosinophils/μL.

INTERPRETATION

A significant U-shaped relationship was found between BEC and severity and exacerbations in bronchiectasis that was more pronounced in the eosinopenic group. IC treatment decreased the number and severity of exacerbations only in the eosinophilic group.

Validation of circulating microRNAs miR-142-3p and miR-598-3p in women with polycystic ovary syndrome as potential diagnostic markers

STUDY QUESTION

Circulating miRNAs previously associated with androgen excess in women might be used as diagnostic biomarkers for polycystic ovary syndrome (PCOS).

SUMMARY ANSWER

Models based on circulating miR-142-3p and miR-598-3p expression show good discrimination among women with and without PCOS, particularly when coupled with easily available measurements such as waist-to-hip ratio (WHR) and circulating LH-to-FSH (LH/FSH) ratios.

WHAT IS KNOWN ALREADY

The lack of standardization of the signs, methods, and threshold values used to establish the presence of the diagnostic criteria (hyperandrogenism, ovulatory dysfunction, and polycystic ovarian morphology) complicates the diagnosis of PCOS. Certain biomarkers may help with such a diagnosis. We conducted a validation study to check the diagnostic accuracy for PCOS of several miRNAs that were associated with the syndrome in a small pilot study that had been previously carried out by our research group.

STUDY DESIGN, SIZE, DURATION

This was a diagnostic test study involving 140 premenopausal women.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We included 71 women with PCOS and 69 healthy control women in the study. Both groups were selected as to be similar in terms of body mass index. We used miRCURY LNA™ Universal RT microRNA PCR to analyse the five miRNAs that had shown the strongest associations with PCOS in a much smaller pilot study previously conducted by our group. We studied diagnostic accuracy using receiver operating characteristics (ROC) curve analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

Only the expression of two miRNAs, miR-142-3p and miR-598-3p, of the five studied, was different between the women with PCOS and the non-hyperandrogenic controls. The diagnostic accuracy of the combination of these circulating miRNAs was good (area under the ROC curve (AUC) 0.801; 95% CI: 0.72-0.88) and was further improved when adding WHR (AUC 0.834, 95% CI: 0.756-0.912), LH/FSH ratio (AUC = 0.869, 95% CI: 0.804-0.934) or both (AUC = 0.895, 95% CI: 0.835-0.954). We developed several models by selecting different threshold values for these variables favouring either sensitivity or specificity, with positive and negative predictive values as high as 88% or 85%, respectively.

LIMITATIONS, REASONS FOR CAUTION

Patients included here had the classic PCOS phenotype, consisting of hyperandrogenism and ovulatory dysfunction; hence, the present results might not apply to milder phenotypes lacking androgen excess.

WIDER IMPLICATIONS OF THE FINDINGS

If confirmed in larger studies addressing different populations and PCOS phenotypes, these biomarkers may be useful to simplify the clinical diagnosis of this prevalent syndrome.

STUDY FUNDING/COMPETING INTEREST(S)

This research was funded by Instituto de Salud Carlos III, Spanish Ministry of Science and Innovation (grants PI15/01686, PIE16/00050, PI18/01122 & PI21/00116) and co-funded by European Regional Development Fund 'A way to make Europe'. Centro de Investigación Biomédica en Red Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM) and Instituto Ramón y Cajal de Investigación Sanitaria (IRYCIS) are also initiatives of the Instituto de Salud Carlos III. The authors have no competing interests to disclose.

TRIAL REGISTRATION NUMBER

N/A.

Pathophysiology of Chronic Bronchial Infection in Bronchiectasis

Bronchiectasis is a complex and heterogeneous disease. Its pathophysiology is poorly understood, but chronic bronchial infection plays an important role in its natural history, and is associated with poor quality of life, more exacerbations and increased mortality. Pseudomonas aeruginosa, Haemophilus influenzae and Staphylococcus aureus are the most common bacteria related to chronic bronchial infection. Non-tuberculous mycobacteria, fungi and respiratory viruses are also present during clinical stability, and may increase the risk of acute exacerbation. Chronic inflammation is present in bronchiectasis, especially neutrophilic inflammation. However, macrophages and eosinophils also play a key role in the disease. Finally, airway epithelium has innate mechanisms such as mucociliary clearance and antibacterial molecules like mucins and antimicrobial peptides that protect the airways from pathogens. This review addresses how the persistence of microorganisms in the airways and the imbalance of the immune system contribute to the development of chronic bronchial infection in bronchiectasis.

Obstructive sleep apnoea is related to melanoma aggressiveness through paraspeckle protein-1 upregulation

BACKGROUND

In patients with obstructive sleep apnoea (OSA), intermittent hypoxia induces overexpression of paraspeckle component (PSPC)1, a master modulator of transforming growth factor (TGF)-β signalling, which promotes cell cancer progression through epithelial-mesenchymal transition (EMT) and acquisition of cancer stem cell (CSC)-like features. However, the persistence of intermittent hypoxia-induced effects on PSPC1, and their consequences in cancer patients are not known. To this effect, circulating PSPC1 levels were compared in patients with cutaneous melanoma with or without OSA, and their relationship with tumour aggressiveness along with the in vitro effects of soluble PSPC1 and intermittent hypoxia on melanoma cell aggressiveness mechanisms were assessed.

METHODS

In 292 cutaneous melanoma patients, sleep studies and serum levels of PSPC1 and TGF-β were evaluated. The effect of PSPC1 on expression of EMT and CSC transcription factors was assessed using melanoma cell lines with patient sera under both normoxia and intermittent hypoxia conditions.

RESULTS

PSPC1 levels were higher in patients with moderate-severe OSA compared with mild OSA or non-OSA patients. Serum levels of PSPC1 were associated with several cutaneous melanoma clinical aggressiveness indicators. Both intermittent hypoxia exposures and serum from OSA patients upregulated TGF-β expression and amplified the expression of transcription factors associated with EMT activation and acquisition of CSC characteristics.

CONCLUSION

In cutaneous melanoma patients, OSA severity is associated with higher PSPC1 serum levels, which jointly with intermittent hypoxia would enhance the self-reprogramming capabilities of EMT and CSC feature acquisition of melanoma cells, promoting their intrinsic aggressiveness.

Inhaled Corticosteroids in Adults with Non-cystic Fibrosis Bronchiectasis: From Bench to Bedside. A Narrative Review

Due to their potent anti-inflammatory capacity (particularly in predominantly eosinophilic inflammation) and immunosuppressive properties, inhaled corticosteroids (ICSs) are widely used in asthmatic patients and also in individuals with chronic obstructive pulmonary disease (COPD) who suffer multiple exacerbations or have peripheral eosinophilia. However, there is little evidence for their use in non-cystic fibrosis bronchiectasis (hereafter, bronchiectasis). According to data extracted from large databases of bronchiectasis in adults, ICSs are used in more than 50% of patients without any scientific evidence to justify their efficacy and contrary to the recommendations of international guidelines on bronchiectasis that generally advise against their use. Indeed, bronchiectasis is a disease with predominantly neutrophilic inflammation and a high likelihood of chronic bacterial bronchial infection. Furthermore, it is known that due to their immunosuppressive properties, ICSs can induce an increase in bacterial infections. This manuscript aims to review the basic properties of ICSs, how they impact bronchiectasis in adults, the current position of international guidelines on this treatment, and the current indications and future challenges related to ICS use in bronchiectasis.

The Human Mycobiome in Chronic Respiratory Diseases: Current Situation and Future Perspectives

Microbes play an important role in the pathogenesis of chronic lung diseases, such as chronic obstructive pulmonary disease, cystic fibrosis, non-cystic fibrosis bronchiectasis, and asthma. While the role of bacterial pathogens has been extensively studied, the contribution of fungal species to the pathogenesis of chronic lung diseases is much less understood. The recent introduction of next-generation sequencing techniques has revealed the existence of complex microbial lung communities in healthy individuals and patients with chronic respiratory disorders, with fungi being an important part of these communities’ structure (mycobiome). There is growing evidence that the components of the lung mycobiome influence the clinical course of chronic respiratory diseases, not only by direct pathogenesis but also by interacting with bacterial species and with the host’s physiology. In this article, we review the current knowledge on the role of fungi in chronic respiratory diseases, which was obtained by conventional culture and next-generation sequencing, highlighting the limitations of both techniques and exploring future research areas.

Rationale and Clinical Use of Bronchodilators in Adults with Bronchiectasis

Currently, there is much controversy surrounding the therapeutic approach to pulmonary function abnormalities in patients with bronchiectasis and, consequently, whether and when to use bronchodilators in these patients. National and international guidelines on the treatment of bronchiectasis in adults do not recommend the routine use of bronchodilators because there is no evidence that a significant response to a bronchodilator or the presence or hyperresponsiveness of the airway are good predictors of future effective clinical response. However, some guidelines recommend them in the presence of airway obstruction and/or special conditions, which vary according to the guideline in question, although there are no recommendations on optimal dosing and bronchodilator treatment combined with or without inhaled corticosteroids. Nonetheless, in contrast with guideline recommendations, bronchodilators are overused in real-world patients with bronchiectasis even in the absence of airway obstruction, as demonstrated by analysis of national and international registries. This overuse can be explained by the awareness of the existence of a solid pharmacological rationale that supports the use of bronchodilators in the presence of chronic airway obstruction independent of its aetiology. We performed a systematic review of the literature and were able to verify that there are no randomised controlled trials (apart from a small study with methodological limitations and a very recent trial involving a not-very-large number of patients), or any long-term observational studies on the short- or long-term effect of bronchodilators in patients with bronchiectasis. Therefore, we believe that it is essential and even urgent to evaluate the effects of bronchodilators in these patients with appropriately designed studies.

Sleep apnoea in the elderly: a great challenge for the future

Due in part to overall improvements in health, the population of elderly individuals is increasing rapidly. Similarly, obstructive sleep apnoea (OSA) is both gaining increased recognition and also increasing due to the worldwide obesity epidemic. The overlap of OSA and aging is large, but there is strong plausibility for causation in both directions: OSA is associated with pathological processes that may accelerate aging and aging related processes; aging may cause physical and neurological changes that predispose to obstructive (and central) apnoea. In addition, the common symptoms (e.g. excessive daytime somnolence, defects in memory and cognition), possible physiological consequences of OSA (e.g. accelerated cardiovascular and cerebrovascular atherosclerosis), and changes in metabolic and inflammatory markers overlap with the symptoms and associated conditions seen in aging. There is also the possibility of synergy in the effects of these symptoms and conditions on quality of life, as well as a need to separate treatable consequences of OSA from age-related complaints. Taken together, the above make it essential to review the interaction of OSA and aging, both proven and suspected. The present review examines some aspects of what is known and points to the need for further investigation of the relationships, given the large number of potentially affected subjects.

Risk Factors and Relation with Mortality of a New Acquisition and Persistence of Pseudomonas aeruginosa in COPD Patients

The isolation of Pseudomonas aeruginosa (PA) in patients with chronic obstructive pulmonary disease (COPD) is associated with increased mortality. Yet, factors associated with first PA sputum isolation, and PA persistence have not been investigated before. The objective of the present study was to investigate risk factors for new acquisition and persistence of PA infection and their relationship with all-cause mortality in patients with COPD. Post-hoc analysis of prospectively collected cohort of 170 COPD patients (GOLD II-IV) who were free of previous PA isolation and followed up every 3-6 months for 85 [50.25-110.25] months. PA was isolated for the first time in 41 patients (24.1%) after 36 [12-60] months of follow-up. Risk factor for first PA isolation were high cumulative smoking exposure, severe airflow limitation, previous severe exacerbations, high fibrinogen levels and previous isolation of Haemophilus Influenzae. PA was isolated again one or more times during follow-up in 58.5% of these patients. This was significantly associated with the presence of CT bronchiectasis and persistence of severe exacerbations, whereas the use of inhaled antibiotic treatment after the first PA isolation (at the discretion of the attending physician) reduced PA persistence. During follow-up, 79 patients (46.4%) died. A single PA isolation did not increase mortality, but PA persistence did (HR 3.06 [1.8-5.2], p = 0.001). We conclude that PA occurs frequently in clinically stable COPD patients, risk factors for a first PA isolation and PA persistence are different, and the latter (but not the former) is associated with increased all-cause mortality.

Bronchial Infection and Temporal Evolution of Bronchiectasis in Patients With Chronic Obstructive Pulmonary Disease

BACKGROUND

Bronchiectasis (BE) impact the clinical course and prognosis of patients with chronic obstructive pulmonary disease (COPD). Yet, the temporal evolution of BE in these patients is unknown. This study seeks to assess the temporal evolution of BE in persons with COPD.

METHODS

201 moderate-to-severe patients were recruited between 2004 and 2007 and followed up at least every 6 monts (median of 102 months). To investigate the temporal evolution of BE, in 2015 a second high-resolution computed tomography scan (HRCT) was obtained in survivors and compared with the one obtained at recruitment.

RESULTS

99 (49.3%) died during follow-up. The second HRCT could be obtained in 77 patients and showed that (1) in 27.3% of patients BE never developed, in 36.4% they remained stable, in 16.9% they increased in size and/or extension, and in 19.5% new BE emerged; and that (2) the presence of chronic purulent sputum (hazard ratio [HR], 2.8 [95% confidence interval {CI}, 1.3-5.8]), number of hospitalizations due to exacerbatons (HR, 1.2 [95% CI, 1.1-1.5]), and number of pathogenic microorganism (PPM) isolations (HR, 1.1 [95% CI, 1.02-1.3]) were independent risk factors for the progression or development of BE.

CONCLUSIONS

The presence of chronic purulent sputum production, number of PPMs isolated in sputum, and number of hospitalizations due to exacerbations of COPD are independent risk factors of BE progression in patients with COPD.

[SEPAR Recommendations for COVID-19 Vaccination in Patients With Respiratory Diseases]

The Spanish Society of Pneumonology and Thoracic Surgery (SEPAR) has elaborated this document of recommendations for COVID-19 vaccination in patients with respiratory diseases aimed to help healthcare personnel make decisions about how to act in case of COVID-19 vaccination in these patients.The recommendations have been developed by a group of experts in this field after reviewing the materials published up to March 7, 2021, the information provided by different scientific societies, drug agencies and the strategies of the governmental bodies up to this date.We can conclude that COVID-19 vaccines are not only safe and effective, but also prior in vulnerable patients with chronic respiratory diseases. In addition, an active involvement of healthcare professionals, who manage these diseases, in the vaccination strategy is the key to achieve good adherence and high vaccination coverage.

Personalized approaches to bronchiectasis

Introduction: Interest in bronchiectasis is increasing due to its rising prevalence, associated with aging populations and the extended use of high-resolution chest tomography (HRCT), and the resulting high morbidity, mortality, and demand for resources.Areas covered: This article provides an extensive review of bronchiectasis as a complex and heterogeneous disease, as well as examining the difficulty of establishing useful clinical phenotypes. In keeping with the aims of 'precision medicine', we address the disease of bronchiectasis from three specific perspectives: severity, activity, and impact. We used PubMed to search the literature for articles including the following keywords: personalized medicine, bronchiectasis, biomarkers, phenotypes, precision medicine, treatable traits. We reviewed the most relevant articles published over the last 5 years.Expert opinion: This article reflects on the usefulness of these three dimensions in 'control panels' and clinical fingerprinting, as well as approaches to personalized medicine and the treatable features of bronchiectasis non-cystic fibrosis.

Canonical Pathways Associated with Blood Pressure Response to Sleep Apnea Treatment: A Post Hoc Analysis

BACKGROUND

Several studies have reported an association between microRNAs (miRNAs) and hypertension or cardiovascular disease (CVD). In a previous study performed on a group of 38 patients, we observed a cluster of 3 miRNAs (miR-378a-3p, miR-100-5p, and miR-486-5p) that were functionally associated with the cardiovascular system that predicted a favorable blood pressure (BP) response to continuous positive airway pressure (CPAP) treatment in patients with resistant hypertension (RH) and obstructive sleep apnea (OSA) (HIPARCO score). However, little is known regarding the molecular mechanisms underlying this phenomenon.

OBJECTIVES

The aim of the study was to perform a post hoc analysis to investigate the genes, functions, and pathways related to the previously found HIPARCO score miRNAs.

METHODS

We performed an enrichment analysis using Ingenuity pathway analysis. The genes potentially associated with the miRNAs were filtered based on their confidence level. Particularly for CVD, only the genes regulated by at least 2 of the miRNAs were studied.

RESULTS

We observed that the miRNAs studied regulate 200-249 molecules associated with several functions and diseases, including extracranial solid tumors and abdominal neoplasms, among others. The cardiac hypertrophy and NF-kB signaling pathways were identified as the cardiovascular pathways most influenced by these 3 miRNAs.

CONCLUSIONS

The mechanisms by which CPAP treatment decreases the BP in OSA patients with RH could be related to the cardiac hypertrophy and NF-kB signaling pathways. Further investigations will be necessary to confirm these findings, contributing to the elucidation of new therapeutic targets in patients who do not respond to CPAP treatment.

Incidence, risk factors, and thrombotic load of pulmonary embolism in patients hospitalized for COVID-19 infection

OBJECTIVE

To determine the incidence, characteristics, and risk factors of pulmonary embolism (PE) among patients hospitalized for COVID-19.

PATIENTS AND METHODS

We performed a prospective observational study of a randomly selected cohort of consecutive patients hospitalized for COVID-19 infection between March 8, 2020 through April 25, 2020. All eligible patients underwent a computed tomography pulmonary angiography independently of their PE clinical suspicion and were pre-screened for a baseline elevated D-dimer level.

RESULTS

119 patients were randomly selected from the 372 admitted to one tertiary hospital in Valencia (Spain) for COVID-19 infection during the period of study. Seventy-three patients fulfilled both the inclusion criteria and none of the exclusion criteria and were finally included in the study. Despite a high level of pharmacological thromboprophylaxis (89%), the incidence of PE was 35.6% (95% confidence interval [CI], 29.6 to 41.6%), mostly with a peripheral location and low thrombotic load (Qanadli score 18.5%). Multivariate analysis showed that heart rate (Hazard Ratio [HR], 1.04), room-air oxygen saturation (spO2) (HR, 0.87), D-dimer (HR, 1.02), and C-reactive protein (CRP) levels (HR, 1.01) at the time of admission were independent predictors of incident PE during hospitalization. A risk score was constructed with these four variables showing a high predictive value of incident PE (AUC-ROC: 0.86; 95% CI: 0.80 to 0.93).

CONCLUSIONS

Our findings confirmed a high incidence of PE in hospitalized COVID-19 patients. Heart rate, spO2, D-dimer, and CRP levels at admission were associated with higher rates of PE during hospitalization.

Coagulation disorders and thromboembolic disease in COVID-19: review of current evidence in search of a better approach

The new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been an unprecedented global health problem, causing more than 20 million infections and more than 900,000 deaths (September 2020). The SARS-CoV-2 infection, known as COVID-19, has various clinical presentations, from asymptomatic or mild catarrhal processes to severe pneumonia that rapidly progresses to acute respiratory distress syndrome (ARDS) and multiple organ failure. In the last few months, much scientific literature has been devoted to descriptions of different aspects of the coagulation disorders and arterial and venous thrombotic complications associated with COVID-19, particularly venous thromboembolism (VTE). These studies have revealed that SARS-CoV-2 could lead to a prothrombotic state reflecting the high cumulative incidence of associated thrombotic events, particularly in patients admitted to intensive care units (ICUs). As regards the coagulopathy observed in association with SARS-CoV-2 infection, the mechanisms that activate coagulation have been hypothesized as being linked to immune responses, through the release of pro-inflammatory mediators that interact with platelets, stimulate the expression of tissue factor, induce an upregulation of plasminogen activator inhibitor-1, suppress the fibrinolytic system and lead to endothelial dysfunction, triggering thrombogenesis. D-dimer elevation has been recognized as a useful biomarker of poor prognosis, although the best cut-off point for predicting VTE in COVID-19 patients has still not been clarified. This review will try to update all the available scientific information on this important topic with enormous clinical and therapeutic implications.