Fatal cardiac air embolism after CT-guided percutaneous needle lung biopsy: medical complication or medical malpractice?

Computed tomography (CT)-guided percutaneous needle biopsy of the lung is a well-recognized and relatively safe diagnostic procedure for suspicious lung masses. Systemic air embolism (SAE) is a rare complication of transthoracic percutaneous lung biopsies. Herein, we present a case of an 81-year-old man who underwent CT-guided percutaneous needle biopsy of a suspicious nodule in the lower lobe of the right lung. Shortly after the procedure, the patient coughed up blood which prompted repeat CT imaging. He was found to have a massive cardiac air embolism. The patient became unresponsive and, despite resuscitation efforts, was pronounced dead. The pathophysiology, risk factors, clinical features, radiological evidence, and autopsy findings associated with SAE are discussed, which may, in light of the current literature, assist with the dilemma between assessing procedural complications and medical liability. Given the instances of SAE in the setting of long operative procedures despite careful technical execution, providing accurate and in-depth information, including procedure-related risks, even the rarest but potentially fatal ones, is recommended for informed consent to reduce medicolegal litigation issues.

Lung cancer in patients with idiopathic pulmonary fibrosis: A retrospective multicentre study in Europe.

BACKGROUND AND OBJECTIVE: There remains a paucity of large databases for patients with idiopathic pulmonary fibrosis (IPF) and lung cancer. We aimed to create a European registry. METHODS: This was a multicentre, retrospective study across seven European countries between 1 January 2010 and 18 May 2021. RESULTS: We identified 324 patients with lung cancer among 3178 patients with IPF (prevalence = 10.2%). By the end of the 10 year-period following IPF diagnosis, 26.6% of alive patients with IPF had been diagnosed with lung cancer. Patients with IPF and lung cancer experienced increased risk of all-cause mortality than IPF patients without lung cancer (HR: 1.51, [95% CI: 1.22-1.86], p < 0.0001). All-cause mortality was significantly lower for patients with IPF and lung cancer with a monocyte count of either <0.60 or 0.60-<0.95 K/µl than patients with monocyte count ≥0.95 K/µl (HR [<0.60 vs. ≥0.95 K/µl]: 0.35, [95% CI: 0.17-0.72], HR [0.60-<0.95 vs. ≥0.95 K/µl]: 0.42, [95% CI: 0.21-0.82], p = 0.003). Patients with IPF and lung cancer that received antifibrotics presented with decreased all cause-mortality compared to those who did not receive antifibrotics (HR: 0.61, [95% CI: 0.42-0.87], p = 0.006). In the adjusted model, a significantly lower proportion of surgically treated patients with IPF and otherwise technically operable lung cancer experienced all-cause mortality compared to non-surgically treated patients (HR: 0.30 [95% CI: 0.11-0.86], p = 0.02). CONCLUSION: Lung cancer exerts a dramatic impact on patients with IPF. A consensus statement for the management of patients with IPF and lung cancer is sorely needed.

Radiomics of spinal muscles: toward a radiological biomarker for allograft rejection in lung transplant.

PURPOSE: To assess the role of muscle composition and radiomics in predicting allograft rejection in lung transplant. MATERIAL AND METHODS: The last available HRCT before surgery of lung transplant candidates referring to our tertiary center from January 2010 to February 2020 was retrospectively examined. Only scans with B30 kernel reconstructions and 1 mm slice thickness were included. One radiologist segmented the spinal muscles of each patient at the level of the 11th dorsal vertebra by an open-source software. The same software was used to extract Hu values and 72 radiomic features of first and second order. Factor analysis was applied to select highly correlating features and then their prognostic value for allograft rejection was investigated by logistic regression analysis (level of significance p < 0.05). In case of significant results, the diagnostic value of the model was computed by ROC curves. RESULTS: Overall 200 patients had a HRCT prior to the transplant but only 97 matched the inclusion criteria (29 women; mean age 50.4 ± 13 years old). Twenty-one patients showed allograft rejection. The following features were selected by the factor analysis: cluster prominence, Imc2, gray level non-uniformity normalized, median, kurtosis, gray level non-uniformity, and inverse variance. The radiomic-based model including also Hu demonstrated that only the feature Imc2 acts as a predictor of allograft rejection (p = 0.021). The model showed 76.6% accuracy and the Imc2 value of 0.19 demonstrated 81% sensitivity and 64.5% specificity in predicting lung transplant rejection. CONCLUSION: The radiomic feature Imc2 demonstrated to be a predictor of allograft rejection in lung transplant.

Molecular Mechanism in the Development of Pulmonary Fibrosis in Patients with Sarcoidosis.

Sarcoidosis is a multisystemic disease of unknown etiology characterized by the formation of granulomas in various organs, especially lung and mediastinal hilar lymph nodes. The clinical course and manifestations are unpredictable: spontaneous remission can occur in approximately two thirds of patients; up to 20% of patients have chronic course of the lung disease (called advanced pulmonary sarcoidosis, APS) resulting in progressive loss of lung function, sometimes life-threatening that can lead to respiratory failure and death. The immunopathology mechanism leading from granuloma formation to the fibrosis in APS still remains elusive. Recent studies have provided new insights into the genetic factors and immune components involved in the clinical manifestation of the disease. In this review we aim to summarize the clinical-prognostic characteristics and molecular pathways which are believed to be associated with the development of APS.

Radiological Assessment in Idiopathic Pulmonary Fibrosis (IPF) Patients According to MUC5B Polymorphism.

The MUC5B rs35705950 mutant T allele is the strongest genetic risk factor for familial and sporadic IPF. We sought to determine whether MUC5B genotype influences radiological patterns of IPF at diagnosis, as well as their change over time, in patients on antifibrotic therapy. Among eighty-eight IPF patients, previously genotyped for MUC5B rs35705950, we considered seventy-eight patients who were evaluated for radiological quantification of the following features both at treatment initiation (HRCT1) and after 1 year (HRCT2): ground glass opacities (AS), reticulations (IS) and honeycombing (HC). Of the evaluated patients, 69% carried at least one copy of the T allele (TT/TG). Carriers of the T allele displayed similar FVC loss in the first year of treatment as GG carriers, but overall survival at the end of follow-up was longer in the TT/TG group, compared to the GG group. In the GG group, both the AS and HC increased significantly, whereas in the TT/TG group only HC increased over the first year of treatment. MUC5B rs35705950 GG carriers are associated with increased ground glass and honeycombing extent over time and worse survival than T allele carriers. Longitudinal HRCT may help define the prognostic role of the MUC5B rs35705950 genotype.

RNA Sequencing of Epithelial Cell/Fibroblastic Foci Sandwich in Idiopathic Pulmonary Fibrosis: New Insights on the Signaling Pathway.

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal lung disease characterized by irreversible scarring of the distal lung. IPF is best described by its histopathological pattern of usual interstitial pneumonia (UIP), characterized by spatial heterogeneity with alternating interstitial fibrosis and areas of normal lung, and temporal heterogeneity of fibrosis characterized by scattered fibroblastic foci (FF), dense acellular collagen and honeycomb changes. FF, comprising aggregated fibroblasts/myofibroblasts surrounded by metaplastic epithelial cells (EC), are the cardinal pathological lesion and their presence strongly correlates with disease progression and mortality. We hypothesized that the EC/FF sandwich from patients with UIP/IPF has a distinct molecular signature which could offer new insights into the crosstalk of these two crucial actors in the disease. Laser capture microdissection with RNAseq was used to investigate the transcriptome of the EC/FF sandwich from IPF patients versus controls (primary spontaneous pneumothorax). Differentially expressed gene analysis identified 23 up-regulated genes mainly related to epithelial dysfunction. Gene ontology analysis highlighted the activation of different pathways, mainly related to EC, immune response and programmed cell death. This study provides novel insights into the IPF pathogenetic pathways and suggests that targeting some of these up-regulated pathways (particularly those related to secreto-protein/mucin dysfunction) may be beneficial in IPF. Further studies in a larger number of lung samples, ideally from patients with early and advanced disease, are needed to validate these findings.

Microvesicles in bronchoalveolar lavage as a potential biomarker of COPD.

Microvesicles (MVs) released from almost all cells are recognized as cell communication tools. MVs have been investigated in several inflammatory diseases but poorly in biological fluids like bronchoalveolar lavage (BAL) of smokers. The purpose of this study was to investigate the presence and source of MVs in BAL of smokers with and without chronic obstructive pulmonary disease (COPD) compared with nonsmoking controls. Using flow cytometry in BAL, we detected endothelial and alveolar macrophage (AM)-derived MVs and found a higher number of AM-MVs in the BAL of smokers with COPD than in smokers without COPD and nonsmokers, which correlated with the pack-years (r = 0.46; P = 0.05) and with the degree of airway obstruction measured by the forced expiratory volume in 1 s percent predicted (r = -0.56; P = 0.01). Endothelial and alveolar macrophage-derived MVs are present and measurable in human BAL fluid. In response to smoking and to the development of COPD, inflammatory signals in AM-derived MVs can be quantified, and their numbers are related to the pack-years and the decrease in lung function. These results open the opportunity for future investigation of these microvesicles as biomarkers and possible mechanistic guides in COPD.

Prognostic role of MUC5B rs35705950 genotype in patients with idiopathic pulmonary fibrosis (IPF) on antifibrotic treatment.

BACKGROUND: A common variant located in the promoter region of MUC5B (rs35705950) is the strongest risk factor for sporadic and familiar IPF, as well as a predictor of outcome. However, there are no data on the effect of MUC5B rs35705950 genotype on the prognosis of IPF patients on antifibrotic treatment. The aim of this study is to determine, in a phenotypically well-characterized population of patients with IPF treated with antifibrotics, the impact of MUC5B rs35705950 genotype on disease progression and survival. METHODS: 88 IPF patients on antifibrotic treatment were followed-up from 2014 until transplantation, death or end of follow-up (December 2019). Disease progression was defined as a forced vital capacity (FVC) loss ≥ 5% per year. All patients were genotyped for MUC5B rs35705950 by PCR amplification and Sanger sequencing. RESULTS: Out of 88 patients, 61 (69%) carried the mutant T allele (TT or TG) and 27 (31%) did not (GG). Carriage of the MUC5B rs35705950 T allele was not associated with a faster decline in FVC. Conversely, at the end of the follow-up, overall survival in carriers of the TT/TG genotype was longer compared to that of the GG genotype carriers. FVC (L) at baseline and time to respiratory failure at rest were independent predictors of worse prognosis. CONCLUSIONS: In IPF patients on antifibrotic treatment, carriage of the MUC5B rs35705950 T allele is associated with longer survival, highlighting the usefulness of MUC5B genetic data in clinical decision making.

Low-Blood Lymphocyte Number and Lymphocyte Decline as Key Factors in COPD Outcomes: A Longitudinal Cohort Study.

BACKGROUND: Smokers with and without chronic obstructive pulmonary disease (COPD) are at risk of severe outcomes like exacerbations, cancer, respiratory failure, and decreased survival. The mechanisms for these outcomes are unclear; however, there is evidence that blood lymphocytes (BL) number might play a role. OBJECTIVE: The objective of this study is to investigate the relationship between BL and their possible decline over time with long-term outcomes in smokers with and without COPD. METHODS: In 511 smokers, 302 with COPD (COPD) and 209 without COPD (noCOPD), followed long term, we investigated whether BL number and BL decline over time might be associated with long-term outcomes. Smokers were divided according to BL number in high-BL (≥1,800 cells/µL) and low-BL (<1,800 cells/µL). Clinical features, cancer incidence, and mortality were recorded during follow-up. BL count in multiple samples and BL decline over time were calculated and related to outcomes. RESULTS: BL count was lower in COPD (1,880 cells/µL) than noCOPD (2,300 cells/µL; p < 0.001). 43% of COPD and 23% of noCOPD had low-BL count (p < 0.001). BL decline over time was higher in COPD than noCOPD (p = 0.040). 22.5% of the whole cohort developed cancer which incidence was higher in low-BL subjects and in BL decliners than high-BL (31 vs. 18%; p = 0.001) and no decliners (32 vs. 19%; p = 0.002). 26% in the cohort died during follow-up. Furthermore, low-BL count, BL decline, and age were independent risk factors for mortality by Cox regression analysis. CONCLUSION: BL count and BL decline are related to worse outcomes in smokers with and without COPD, which suggests that BL count and decline might play a mechanistic role in outcomes deterioration. Insights into mechanisms inducing the fall in BL count could improve the understanding of COPD pathogenesis and point toward new therapeutic measures.

Critical Review of the Evolution of Extracellular Vesicles' Knowledge: From 1946 to Today.

Extracellular vesicles (EVs) are a family of particles/vesicles present in blood and body fluids, composed of phospholipid bilayers that carry a variety of molecules that can mediate cell communication, modulating crucial cell processes such as homeostasis, induction/dampening of inflammation, and promotion of repair. Their existence, initially suspected in 1946 and confirmed in 1967, spurred a sharp increase in the number of scientific publications. Paradoxically, the increasing interest for EV content and function progressively reduced the relevance for a precise nomenclature in classifying EVs, therefore leading to a confusing scientific production. The aim of this review was to analyze the evolution of the progress in the knowledge and definition of EVs over the years, with an overview of the methodologies used for the identification of the vesicles, their cell of origin, and the detection of their cargo. The MISEV 2018 guidelines for the proper recognition nomenclature and ways to study EVs are summarized. The review finishes with a "more questions than answers" chapter, in which some of the problems we still face to fully understand the EV function and potential as a diagnostic and therapeutic tool are analyzed.

CA 19-9 serum levels in patients with end-stage idiopathic pulmonary fibrosis (IPF) and other interstitial lung diseases (ILDs): Correlation with functional decline.

Idiopathic pulmonary fibrosis presents a progressive and heterogeneous functional decline. CA 19-9 has been proposed as biomarker to predict disease course, but its role remains unclear. We assessed CA 19-9 levels and clinical data in end-stage ILD patients (48 IPF and 20 non-IPF ILD) evaluated for lung transplant, to correlate these levels with functional decline. Patients were categorized based on their rate of functional decline as slow (n = 20; ΔFVC%pred ≤ 10%/year) or rapid progressors (n = 28; ΔFVC%pred ≥ 10%/year). Nearly half of the entire patients (n = 32; 47%) had CA 19-9 levels ≥37kU/L. CA 19-9 levels in IPF were not different from non-IPF ILD populations, however, the latter group had a median CA 19-9 level above the normal cut-off value of 37 KU/l (60 [17-247] kU/L). Among IPF patients, CA 19-9 was higher in slow than in rapid progressors with a trend toward significance (33vs17kU/L; p = 0.055). In the whole population, CA19-9 levels were inversely related with ΔFVC/year (r = -0.261; p = 0.03), this correlation remained in IPF patients, particularly in rapid progressors (r = -0.51; p = 0.005), but not in non. Moreover, IPF rapid progressors with normal CA 19-9 levels showed the greater ΔFVC/year compared to those with abnormal CA 19-9 (0.95 vs. 0.65 L/year; p = 0.03). In patients with end-stage ILD, CA 19-9 may represent a marker of disease severity, whereas its level is inversely correlated with functional decline, particularly among IPF rapid progressors.

The Role of the Lung's Microbiome in the Pathogenesis and Progression of Idiopathic Pulmonary Fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrosing interstitial lung disease that commonly affects older adults and is associated with the histopathological and/or radiological patterns of usual interstitial pneumonia (UIP). Despite significant advances in our understanding of disease pathobiology and natural history, what causes IPF remains unknown. A potential role for infection in the disease's pathogenesis and progression or as a trigger of acute exacerbation has long been postulated, but initial studies based on traditional culture methods have yielded inconsistent results. The recent application to IPF of culture-independent techniques for microbiological analysis has revealed previously unappreciated alterations of the lung microbiome, as well as an increased bacterial burden in the bronchoalveolar lavage (BAL) of IPF patients, although correlation does not necessarily entail causation. In addition, the lung microbiome remains only partially characterized and further research should investigate organisms other than bacteria and viruses, including fungi. The clarification of the role of the microbiome in the pathogenesis and progression of IPF may potentially allow its manipulation, providing an opportunity for targeted therapeutic intervention.

Idiopathic Pulmonary Fibrosis and Lung Transplantation: When it is Feasible.

Despite the availability of antifibrotic therapies, many patients with idiopathic pulmonary fibrosis (IPF) will progress to advanced disease and require lung transplantation. International guidelines for transplant referral and listing of patients with interstitial lung disease are not specific to those with IPF and were published before the widespread use of antifibrotic therapy. In this review, we discussed difficulties in decision-making when dealing with patients with IPF due to the wide variability in clinical course and life expectancy, as well as the acute deterioration associated with exacerbations. Indeed, the ideal timing for referral and listing for lung transplant remains challenging, and the acute deterioration might be influenced after transplant outcomes. Of note, patients with IPF are frequently affected by multimorbidity, thus a screening program for occurring conditions, such as coronary artery disease and pulmonary hypertension, before lung transplant listing is crucial to candidate selection, risk stratification, and optimal outcomes. Among several comorbidities, it is of extreme importance to highlight that the prevalence of lung cancer is increased amongst patients affected by IPF; therefore, candidates' surveillance is critical to avoid organ allocation to unsuitable patients. For all these reasons, early referral and close longitudinal follow-up for potential lung transplant candidates are widely encouraged.

Clinical and Pathologic Factors Predicting Future Asthma in Wheezing Children. A Longitudinal Study.

Wheeze is a common symptom in infants, but not all wheezers develop asthma. Indeed, up to 50% of wheezing children outgrow their symptoms by school age. How to predict if early wheeze will become asthma is still a matter of vivid debate. In this work, we sought to assess the clinical and pathological factors that might predict the future development of asthma in children. Eighty children (mean age 3.8 ± 1 yr) who underwent a clinically indicated bronchoscopy were followed prospectively for a median of 5 years. At baseline, clinical characteristics with a particular focus on wheezing and its presentation (episodic or multitrigger) were collected, and structural and inflammatory changes were quantified in bronchial biopsies. Follow-up data were available for 74 of the 80 children. Children who presented with multitrigger wheeze were more likely to have asthma at follow-up than those with episodic wheeze (P = 0.04) or without wheeze (P < 0.0001). Children with asthma also had lower birth weights (P = 0.02), a lower prevalence of breastfeeding (P = 0.02), and a trend for increased IgE (P = 0.07) at baseline than those with no asthma. Basement membrane thickness and airway eosinophils at baseline were increased in children who developed asthma at follow-up (P = 0.001 and P = 0.026, respectively). Multivariate analysis showed that among all clinical and pathological factors, multitrigger wheezing, basement membrane thickening, and reduced birth weight were predictive of future asthma development. We conclude that multitrigger wheeze and reduced birth weight are clinical predictors of asthma development. Basement membrane thickening in early childhood is closely associated with asthma development, highlighting the importance of airway remodeling in early life as a risk factor for future asthma.

A Real-Life Multicenter National Study on Nintedanib in Severe Idiopathic Pulmonary Fibrosis.

BACKGROUND: Two therapeutic options are currently available for patients with mild-to-moderate idiopathic pulmonary fibrosis (IPF): pirfenidone and nintedanib. To date, there is still insufficient data on the efficacy of these 2 agents in patients with more severe disease. OBJECTIVES: This national, multicenter, retrospective real-life study was intended to determine the impact of nintedanib on the treatment of patients with severe IPF. METHODS: All patients included had severe IPF and had to have at least 6 months of follow-up before and at least 6 months of follow-up after starting nintedanib. The aim of the study was to compare the decline in lung function before and after treatment. Patient survival after 6 months of therapy with nintedanib was assessed. RESULTS: Forty-one patients with a forced vital capacity (FVC) ≤50% and/or a diffusing capacity of the lung for carbon monoxide (DLCO) ≤35% predicted at the start of nintedanib treatment were enrolled. At the 6-month follow-up, the decline of DLCO (both absolute and % predicted) was significantly reduced compared to the pretreatment period (absolute DLCO at the -6-month, T0, and +6-month time points (5.48, 4.50, and 5.03 mmol/min/kPa, respectively, p = 0.03; DLCO% predicted was 32.73, 26.54, and 29.23%, respectively, p = 0.04). No significant beneficial effect was observed in the other functional parameters analyzed. The 1-year survival in this population was 79%, calculated from month 6 of therapy with nintedanib. CONCLUSIONS: This nationwide multicenter experience in patients with severe IPF shows that nintedanib slows down the rate of decline of absolute and % predicted DLCO but does not have significant impact on FVC or other lung parameters.

Dual polarization of human alveolar macrophages progressively increases with smoking and COPD severity.

BACKGROUND: It is known that tissue macrophages derive not only from blood monocytes but also from yolk sac or fetal liver, and the tissue of residence guides their function. When isolated, they lose tissue specific signatures, hence studies of human macrophages should be ideally done directly in the tissue. The aim of this study was to investigate directly in human lung tissue the polarization of alveolar macrophage (AM), classic (M1) or alternative (M2), in health and disease, using COPD as a model. METHODS: Surgical lungs from 53 subjects were studied: 36 smokers whose FEV1 varied from normal to severe COPD, 11 non-smokers and 6 normal donors. iNOS and CD206 immunohistochemistry was used to quantify the percentage of AM polarized as M1 or M2 in lung sections. RESULTS AND DISCUSSION: The percentage of M1 and M2 increased progressively with smoking and COPD severity, from 26% to 84% for M1 and from 7% to 78% for M2. In donors 74% of AM were negative for M1 and 93% for M2. Confocal microscopy showed co-localization of M1 and M2 in the same AM in severe COPD. CONCLUSION: In normal lungs alveolar macrophages were mostly non-polarized. With smoking and COPD severity, M1 and M2 polarization increased significantly and so did the co-expression of M1 and M2 in the same alveolar macrophage.

Alpha-1 Antitrypsin Deficiency Today: New Insights in the Immunological Pathways.

More than 50 years ago, the observation that absence of the α1 band from protein electrophoresis is associated with severe emphysema established the link between α1-antitrypsin deficiency (AATD) and lung damage. From this discovery, the classic paradigm of protease/antiprotease imbalance was derived, linking lung destruction in patients with AATD to the unopposed effect of proteases. By extension, this paradigm was also applied to patients with 'common' chronic obstructive pulmonary disease, in whom large increases in smoke-induced proteases could overwhelm the antiprotease capability of AAT. However, it has become increasingly evident that AAT has important anti-inflammatory and immunoregulatory activities which, beside its antiprotease function, may be critically involved in lung destruction. From this perspective, we will consider recent evidence, based on epidemiological, clinical and immunopathological studies, suggesting that it is time to move on from the original protease/antiprotease paradigm toward a more complex view of the condition, which embraces its immunomodulating functions. Of importance, the potent immunoregulatory, tolerogenic role of AAT may support its therapeutic use in a number of diseases other than AATD, particularly in immune-related disorders.

Immune activation in α1-antitrypsin-deficiency emphysema. Beyond the protease-antiprotease paradigm.

RATIONALE: α1-Antitrypsin (AAT) is a potent protease inhibitor, deficiency of which is associated with the presence of emphysema. An imbalance of elastase and antielastase, along with innate inflammation in the lung, is believed to cause lung destruction in α1-antitrypsin deficiency (AATD). It is now apparent that AAT has important immune-regulatory roles that would be lost in AATD, yet adaptive immune responses in the lung have not been investigated in patients with AATD. OBJECTIVES: To assess the adaptive immune response in severe AATD emphysema and compare it with that present in "usual" chronic obstructive pulmonary disease (COPD). METHODS: The immune inflammatory response in explanted lungs from 10 subjects with AATD was characterized and quantified, and the results were compared with those of 26 subjects with usual COPD and those of 17 smoking and 11 nonsmoking control subjects with normal lung function. MEASUREMENTS AND MAIN RESULTS: Lymphoid follicles (LFs) in AATD and usual COPD were markedly increased when compared with control groups. Molecular analysis of B lymphocytes in LFs showed predominantly mono/oligoclonality. LF number correlated negatively with FEV1/FVC. B lymphocytes and CD4(+) and CD8(+) T lymphocytes were significantly increased in AATD and usual COPD when compared with control groups. IL-32, an important cytokine in induction of autoimmunity, was markedly up-regulated in AATD and usual COPD. CONCLUSIONS: An important adaptive immune inflammation, comprising B, CD4(+), and CD8(+) lymphocytes, and LFs, is a prominent feature in AATD. These results change the paradigm of the mechanism of AATD-induced emphysema from a pure elastase-antielastase imbalance to a much more complex one involving the adaptive immune system, similarly to what occurs in usual COPD.

Right-to-left interatrial shunt secondary to right hemidiaphragmatic paralysis: an unusual scenario for urgent percutaneous closure of patent foramen ovale.

A 66 year-old female presented with a refractory hypoxaemia in association with an isolated paralysis of the right hemidiaphragm. Transoesophageal echocardiography (TEE) with both colour Doppler and bubble test demonstrated a significant patent foramen ovale (PFO)-mediated right-to-left shunt (RTLS) without an increased interatrial pressure gradient. The PFO was urgently closed by deployment of an AMPLATZER(®) occluder device, resulting in complete recovery of the arterial oxygen saturation and patient's symptoms. As noted on TEE, the RTLS was due to redirection of blood flow from the inferior vena cava directly through the PFO secondary to distortion of the cardiac anatomy by right hemidiaphragmatic paralysis.

Long COVID in Immunocompromised and Immunocompetent Patients: A Clinical, Morphologic, and Virologic Portrait.

CONTEXT.­: Coronavirus disease 2019 (COVID) primarily affects the lung and can lead to chronic/post-COVID syndrome. Some insights about late pulmonary changes occurring in patients recovering from COVID have been published, but the evidence of detailed pathologic changes coming from follow-up care patients with long COVID is limited. OBJECTIVE.­: To evaluate tissue morphologic and viral features in transbronchial biopsies of long COVID patients (immunocompetent and immunocompromised). DESIGN.­: This retrospective observational study included 18 patients (9 immunocompetent and 9 immunocompromised) who were consecutively referred to outpatient clinic for post-COVID pneumonia, undergoing transbronchial biopsy. Several histologic changes were analyzed by computer-assisted morphometric analysis. As organizing pneumonia (OP) was consistently detected, fibrosis and inflammation were also evaluated in transbronchial biopsies from 28 control patients with histologic confirmation of OP. Tissue SARS-CoV-2 and the subgenomic transcripts were investigated. Morphologic findings were correlated with clinical and radiologic data. RESULTS.­: Long COVID patients showed lower inflammation than controls (P < .001) despite a similar fibrotic extension. When considering separately the 2 long COVID groups, the same inflammatory infiltrate extension was found, whereas a higher fibrotic remodeling characterized the immunocompetent subgroup (P = .05). Molecular investigation showed that SARS-CoV-2 was present in tissue samples obtained from 3 long COVID patients. CONCLUSIONS.­: Long COVID patients showed a peculiar OP pattern, with more vascular and fibrotic changes. SARS-CoV-2 RNA, even in replicative status, can be detected in lung biopsies of both immunocompetent and immunocompromised patients. This pilot study is a forerunner of more in-depth lung tissue investigations to gain a better understanding of long COVID pathobiology.