Coronary inflammation on chest computed tomography and COVID-19 mortality.

OBJECTIVES: The main factors associated with coronavirus disease-19 (COVID-19) mortality are age, comorbidities, pattern of inflammatory response, and SARS-CoV-2 lineage involved in infection. However, the clinical course of the disease is extremely heterogeneous, and reliable biomarkers predicting adverse prognosis are lacking. Our aim was to elucidate the prognostic role of a novel marker of coronary artery disease inflammation, peri-coronary adipose tissue attenuation (PCAT), available from high-resolution chest computed tomography (HRCT) in COVID-19 patients with severe disease requiring hospitalization. METHODS: Two distinct groups of patients were admitted to Parma University Hospital in Italy with COVID-19 in March 2020 and March 2021 (first- and third-wave peaks of the COVID-19 pandemic in Italy, with the prevalence of wild-type and B.1.1.7 SARS-CoV-2 lineage, respectively) were retrospectively enrolled. The primary endpoint was in-hospital mortality. Demographic, clinical, laboratory, HRCT data, and coronary artery HRCT features (coronary calcium score and PCAT attenuation) were collected to show which variables were associated with mortality. RESULTS: Among the 769 patients enrolled, 555 (72%) were discharged alive, and 214 (28%) died. In multivariable logistic regression analysis age (p < 0.001), number of chronic illnesses (p < 0.001), smoking habit (p = 0.006), P/F ratio (p = 0.001), platelet count (p = 0.002), blood creatinine (p < 0.001), non-invasive mechanical ventilation (p < 0.001), HRCT visual score (p < 0.001), and PCAT (p < 0.001), but not the calcium score, were independently associated with in-hospital mortality. CONCLUSION: Coronary inflammation, measured with PCAT on non-triggered HRCT, appeared to be independently associated with higher mortality in patients with severe COVID-19, while the pre-existent coronary atherosclerotic burden was not associated with adverse outcomes after adjustment for covariates. CLINICAL RELEVANCE STATEMENT: The current study demonstrates that a relatively simple measurement, peri-coronary adipose tissue attenuation (PCAT), available ex-post from standard high-resolution computed tomography, is strongly and independently associated with in-hospital mortality. KEY POINTS: • Coronary inflammation can be measured by the attenuation of peri-coronary adipose tissue (PCAT) on high-resolution CT (HRCT) without contrast media. • PCAT is strongly and independently associated with in-hospital mortality in SARS-CoV-2 patients. • PCAT might be considered an independent prognostic marker in COVID-19 patients if confirmed in other studies.

Gold(III) complexes with thiosemicarbazone ligands: insights into their cytotoxic effects on lung cancer cells.

Cancer continues to pose a global threat, underscoring the urgent need for more effective and safer treatment options. Gold-based compounds have recently emerged as promising candidates due to their diverse range of biological activities. In this study, three gold(III) complexes derived from thiosemicarbazone ligands have been synthesized, fully characterized, including their X-ray crystal structures. We conducted initial mode-of-action studies on DNA and BSA, followed by a comprehensive investigation into the cytotoxic effects of these novel gold(III) complexes on lung cancer cells (A549, H2052, and H28). The results demonstrated a concentration-dependent cytotoxic response, with H28 cells exhibiting the highest sensitivity to the treatment. Furthermore, the analysis of the cell cycle revealed that these compounds induce cell cycle arrest and promote apoptosis as a response to treatment. We also observed distinct morphological changes and increased oxidative stress, contributing significantly to cell death. Notably, these complexes exhibited the ability to suppress interleukin-6 production in mesothelioma cell lines, and this highlights their anti-inflammatory potential. To gain an initial understanding of cytotoxicity on healthy cells, hemolysis tests were conducted against human blood cells, with no evidence of hemolysis. Furthermore, a toxicity assessment through the in vivo Galleria mellonella model underscored the absence of detectable toxicity. These findings prove that these complexes are promising novel therapeutic agents for lung cancer.

Gut Microbiota and Associated Mucosal Immune Response in Eosinophilic Granulomatosis with Polyangiitis (EGPA).

Eosinophilic granulomatosis with polyangiitis (EGPA) is an anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis. A genome-wide association study showed a correlation between ANCA-negative EGPA and variants of genes encoding proteins with intestinal barrier functions, suggesting that modifications of the mucosal layer and consequent gut dysbiosis might be involved in EGPA pathogenesis. Here, we characterized the gut microbiota (GM) composition and the intestinal immune response in a cohort of EGPA patients. Faeces from 29 patients and 9 unrelated healthy cohabitants were collected, and GM and derived metabolites' composition were compared. Seven intestinal biopsies from EGPA patients with gastrointestinal manifestations were analysed to assess the T-cell distribution and its correlation with GM and EGPA clinical and laboratory features. No significant differences in GM composition, nor in the total amount of faecal metabolites, emerged between patients and controls. Nevertheless, differences in bacterial taxa abundances and compositional GM-derived metabolites profile were observed. Notably, an enrichment of potential pathobionts (Enterobacteriacee and Streptococcaceae) was found in EGPA, particularly in patients with active disease, while lower levels were found in patients on immunosuppression, compared with non-immunosuppressed ones. Significantly lower amounts of hexanoic acid were found in patients, compared to controls. The analysis of the immune response in the gut mucosa revealed a high frequency of IFN-γ/IL-17-producing T lymphocytes, and a positive correlation between EGPA disease activity and intestinal T-cell levels. Our data suggest that an enrichment in potential intestinal pathobionts might drive an imbalanced inflammatory response in EGPA.

Clinicopathological Bird's-Eye View of Left Atrial Myocardial Fibrosis in 121 Patients With Persistent Atrial Fibrillation: Developing Architecture and Main Cellular Players.

BACKGROUND: Scientific research on atrial fibrosis in atrial fibrillation (AF) has mainly focused on quantitative or molecular features. The purpose of this study was to perform a clinicoarchitectural/structural investigation of fibrosis to provide one key to understanding the electrophysiological/clinical aspects of AF. METHODS: We characterized the fibrosis (amount, architecture, cellular components, and ultrastructure) in left atrial biopsies from 121 patients with persistent/long-lasting persistent AF (group 1; 59 males; 60±11 years; 91 mitral disease-related AF, 30 nonmitral disease-related AF) and from 39 patients in sinus rhythm with mitral valve regurgitation (group 2; 32 males; 59±12 years). Ten autopsy hearts served as controls. RESULTS: Qualitatively, the fibrosis exhibited the same characteristics in all cases and displayed particular architectural scenarios (which we arbitrarily subdivided into 4 stages) ranging from isolated foci to confluent sclerotic areas. The percentage of fibrosis was larger and at a more advanced stage in group 1 versus group 2 and, within group 1, in patients with rheumatic disease versus nonrheumatic cases. In patients with AF with mitral disease and no rheumatic disease, the percentage of fibrosis and the fibrosis stages correlated with both left atrial volume index and AF duration. The fibrotic areas mainly consisted of type I collagen with only a minor cellular component (especially fibroblasts/myofibroblasts; average value range 69-150 cells/mm2, depending on the areas in AF biopsies). A few fibrocytes-circulating and bone marrow-derived mesenchymal cells-were also detectable. The fibrosis-entrapped cardiomyocytes showed sarcolemmal damage and connexin 43 redistribution/internalization. CONCLUSIONS: Atrial fibrosis is an evolving and inhomogeneous histological/architectural change that progresses through different stages ranging from isolated foci to confluent sclerotic zones which-seemingly-constrain impulse conduction across restricted regions of electrotonically coupled cardiomyocytes. The fibrotic areas mainly consist of type I collagen extracellular matrix and, only to a lesser extent, mesenchymal cells.

Fibrocytes in Chronic Periaortitis: A Novel Mechanism Linking Inflammation and Fibrosis.

OBJECTIVE: Chronic periaortitis (CP) is a rare disease characterized by periaortic and periiliac fibroinflammatory tissue. The pathogenic mechanisms leading to tissue accumulation and activation of fibroblasts are unclear. This study was undertaken to explore the role of fibrocytes, circulating precursors of tissue fibroblasts, in patients with CP. METHODS: We studied 44 patients with newly diagnosed CP and 30 healthy controls. Circulating fibrocytes were identified as Col1+CD45+ cells using flow cytometry. Retroperitoneal tissue biopsy samples from 9 CP patients were stained with anti-type I procollagen, anti-CXCR4, and anti-CD45 antibodies and analyzed by confocal microscopy to detect tissue-infiltrating fibrocytes. Circulating levels and tissue expression of CXCL12, a CXCR4 ligand that promotes fibrocyte homing, were investigated using enzyme-linked immunosorbent assay and immunohistochemistry, respectively. We also characterized T helper polarization in biopsy samples from CP patients and measured serum levels of a panel of cytokines that are hallmarks of T helper responses and capable of influencing fibrocyte differentiation. RESULTS: The frequency of circulating Col1+CD45+ fibrocytes was higher in patients than in controls (P = 0.0371). CD45+proCol1+ and CXCR4+proCol1+ cells were detected in all examined biopsy samples from CP patients. Serum levels of CXCL12 were also higher in CP patients than controls (P = 0.0056), and tissue-infiltrating inflammatory cells intensely expressed CXCL12. Increased serum levels of Th2 cytokines (e.g., interleukin-13 [IL-13] and IL-10) were found in patients, and immunohistochemistry revealed a dominant infiltration of GATA-3+ cells, also indicating Th2 polarization; Th2-skewed responses are known to promote fibrocyte differentiation. CONCLUSION: Our findings indicate that fibrocytes are enriched in the peripheral blood of CP patients and infiltrate target lesions. The accumulation of fibrocytes in the pathologic tissue might be driven by CXCL12, and Th2-skewed immune responses are likely to facilitate their differentiation.

Clinical and Prognostic Significance of Serum IgG4 in Chronic Periaortitis. An Analysis of 113 Patients.

Objective: Chronic periaortitis (CP) is a rare fibro-inflammatory disorder that incorporates idiopathic retroperitoneal fibrosis, inflammatory abdominal aortic aneurysms, and perianeurysmal retroperitoneal fibrosis. CP is included in the spectrum of IgG4-related disease. Since CP patients rarely undergo diagnostic biopsies, serum IgG4 levels are often used to classify CP as IgG4-related. However, the clinical and prognostic significance of serum IgG4 in CP is unknown. Methods: We measured serum IgG4 in active CP patients and compared the clinical characteristics, response to therapy and outcome of patients with high and normal levels. We also tested the diagnostic significance of IgG4 by comparing its levels in CP patients, healthy and disease controls (malignancies, Erdheim-Chester disease, large-, and small-vessel vasculitis). Results: We studied 113 consecutive patients with active CP. Twenty-four (21.2%) had high serum IgG4 (>135 mg/dL). The demographic, laboratory, and clinical characteristics of patients with high and normal IgG4 were similar, and so were the rates of ureteral obstruction and the disease characteristics on CT, MRI, and 18F-FDG-PET. Patients with high IgG4 only had a higher frequency of extra-retroperitoneal fibro-inflammatory lesions (p = 0.005). There were no significant differences in response to therapy and relapses between the two groups. Serum IgG4 levels did not discriminate CP from controls. Conclusions: Serum IgG4 levels are high in a minority of CP patients and do not identify specific clinical or prognostic subgroups; only a higher frequency of extra-retroperitoneal lesions is found in high-IgG4 patients. Serum IgG4 levels do not help in the differential diagnosis between CP and its mimics.

Erdheim-Chester Disease as a Mimic of IgG4-Related Disease: A Case Report and a Review of a Single-Center Cohort.

Immunoglobulin-G4 (IgG4)-related disease (IgG4RD) is a fibro-inflammatory disorder characterized by tissue-infiltrating IgG4 plasma cells, and, often, high serum IgG4. Several autoimmune, infectious, or proliferative conditions mimic IgG4RD. Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis, characterized by foamy histiocytic infiltration, fibrosis, and chronic inflammation. ECD and IgG4RD manifestations may overlap.A patient presented with huge fibrous retroperitoneal masses causing compression on neighboring structures; the case posed the challenge of the differential diagnosis between IgG4RD and ECD mainly because of a prominent serum and tissue IgG4 response.Retroperitoneal biopsy led to the diagnosis of ECD; the V600E BRAF mutation was found. Treatment with the BRAF inhibitor vemurafenib was started.Treatment failed to induce mass regression and the patient died after 3 months of therapy. Prompted by this case, we examined serum and tissue IgG4 in a series of 15 ECD patients evaluated at our center, and found that approximately one-fourth of the cases have increased IgG4 in the serum and often in the tissue.The differential diagnosis between IgG4RD and ECD can be challenging, as some ECD patients have prominent IgG4 responses. This suggests the possibility of common pathogenic mechanisms between ECD and IgG4RD.

Association of Serum C3 Concentration and Histologic Signs of Thrombotic Microangiopathy with Outcomes among Patients with ANCA-Associated Renal Vasculitis.

BACKGROUND AND OBJECTIVES: Complement alternative pathway (cAP) activation has recently been recognized as a key pathogenic event in ANCA-associated vasculitis (AAV). cAP dysregulation is also a major determinant of thrombotic microangiopathies (TMA), which can in turn complicate AAV. We explored the prognostic significance of cAP activation and of histologic evidence of TMA in a cohort of patients with renal AAV. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We studied 46 patients with AAV diagnosed between January 1990 and December 2011 at the Nephrology Unit of Parma University Hospital; 30 of them had undergone renal biopsy. We analyzed serum levels of C3 (sC3) and C4 (sC4) and, for 19 patients who had frozen plasma, plasma Bb and C5b-9 levels. We also reviewed all kidney biopsy specimens, specifically searching for histologic signs of TMA, and performed immunofluorescence or immunohistochemistry for C3d, C4d, Bb and C5b-9. RESULTS: sC3 was below the lower limit of normal in 35% of the patients, whereas C4 was low in only 2%. Patients with low sC3 tended to be older (P=0.04) and to have lower eGFR at diagnosis (P=0.06). The median follow-up was 78 months (interquartile range, 18-135 months); 18 patients reached ESRD (10 of 14 and 8 of 26 in the low and normal sC3 groups, respectively). Death-censored renal survival was lower in the low sC3 group than in the normal sC3 group (log-rank test, P=0.01). Eight of the 30 patients who had undergone biopsy (27%) had histologic signs of TMA; these signs were more frequent in patients with low sC3 (5 of 10 versus 3 of 20; P=0.04). Notably, patients with histologic signs of TMA had a dramatically worse death-censored renal survival than patients without TMA (log-rank test, P=0.01), with ESRD occurring in 8 of 8 patients with TMA versus 8 of 22 patients without TMA. CONCLUSIONS: Low sC3 levels and histologic signs of TMA are associated with a poor renal prognosis in patients with AAV.

Sirolimus plus prednisone for Erdheim-Chester disease: an open-label trial.

Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis, to whose pathogenesis neoplastic and immune-mediated mechanisms contribute. Mammalian target of rapamycin (mTOR)-inhibitors have antiproliferative and immunosuppressive properties. We tested in this study, the efficacy and safety of the mTOR-inhibitor sirolimus (SRL) plus prednisone (PDN) in patients with ECD. PDN was given initially at 0.75 mg/kg per day, tapered to 5 to 2.5 mg per day by month 6. Target SRL blood levels were 8 to 12 ng/mL. Treatment was continued for at least 24 months in patients who showed disease stabilization or improvement. Ten patients were enrolled; 8 achieved stable disease or objective responses, whereas 2 had disease progression. Responses were mainly observed at the following sites: retroperitoneum in 5/8 patients (62.5%), cardiovascular in 3/4 (75%), bone in 3/9 (33.3%), and central nervous system (CNS) in 1/3 (33.3%). The median follow-up was 29 months (interquartile range, 16.5-74.5); 2 patients died of progressive CNS disease and small-cell lung cancer, respectively. Treatment-related toxicity was mild. Using immunohistochemistry and immunofluorescence on ECD biopsies, we detected expression in foamy histiocytes of the phosphorylated forms of mTOR and of its downstream kinase p70S6K, which indicated mTOR pathway activation. In conclusion, SRL and PDN often induce objective responses or disease stabilization and may represent a valid treatment of ECD. The trial is registered at the Australia-New Zealand Clinical Trial Registry as #ACTRN12613001321730.

Interleukin-6 as an inflammatory mediator and target of therapy in chronic periaortitis.

OBJECTIVE: Chronic periaortitis (CP) usually responds to glucocorticoids, but some patients have glucocorticoid-refractory disease or contraindications to glucocorticoid therapy. This study was undertaken to evaluate treatment with the anti-interleukin-6 receptor (anti-IL-6R) antibody tocilizumab in 2 patients with CP, one with refractory disease and the other with contraindications to glucocorticoids, and to assess IL-6 levels in an additional cohort of patients with CP. METHODS: Both patients were given intravenous tocilizumab (8 mg/kg) once every 4 weeks for 6 months. Serum IL-6 was measured in 22 patients with active CP and 16 healthy controls. Tissue IL-6 expression was assessed by confocal microscopy in biopsy specimens obtained from 6 patients with CP. RESULTS: In the first patient, whose disease was refractory to various immunosuppressive treatments, tocilizumab added to ongoing therapy with prednisone and methotrexate allowed prednisone withdrawal and induced resolution of symptoms, acute-phase reactant normalization, and reduction in (18) F-fluorodeoxyglucose ((18) F-FDG) uptake on positron emission tomography. The patient experienced a relapse 7 months later and was successfully retreated with tocilizumab. In the second patient, who was unable to tolerate glucocorticoids because of psychiatric side effects, tocilizumab monotherapy induced sustained clinical and laboratory remission, (18) F-FDG uptake disappearance, and CP shrinkage. Serum IL-6 levels were significantly higher in patients with active CP than in controls (P < 0.0001), and IL-6 was abundantly expressed in biopsy specimens from CP patients, particularly by T cells, B cells, histiocytes, fibroblasts, and vascular smooth muscle cells. CONCLUSION: Tocilizumab may be a therapeutic option for CP. The systemic and tissue up-regulation of IL-6 in CP, together with the clinical benefit of IL-6R blockade observed in our 2 patients, suggest that IL-6 may contribute to CP pathogenesis.