Systematic screening for a proximal DVT in COVID-19 hospitalized patients: Results of a comparative study

INTRODUCTION

The COVID-19 pandemic is associated with a high incidence of venous thromboembolism questioning the utility of a systematic screening for deep venous thrombosis (DVT) in hospitalised patients.

METHODS

In this prospective bicentric controlled study, 4-point ultrasound using a pocket device was used to screen for DVT, in patients with SARS-CoV-2 infection and controls admitted for acute medical illness not related to COVID-19 hospitalised in general ward, in order to assess the utility of a routine screening and to estimate the prevalence of VTE among those patients.

RESULTS

Between April and May 2020, 135 patients were screened, 69 in the COVID+ group and 66 in the control one. There was no significant difference in the rate of proximal DVT between the two groups (2.2% vs. 1.5%; P=0.52), despite the high rate of PE diagnosed among COVID-19 infected patients (10.1% vs. 1.5%, P=0.063). No isolated DVT was detected, 37.5% of PE was associated with DVT. Mortality (7.2% vs. 1.5%) was not different (P=0.21) between COVID-19 patients and controls.

CONCLUSION

The systematic screening for proximal DVT was not found to be relevant among COVID-19 patients hospitalized in general ward despite the increase of VTE among this population. Further studies are needed to confirm the hypothesis of a local pulmonary thrombosis which may lead to new therapeutic targets.

New insights into antiphospholipid-related endothelial dysfunction by assessment of vascular glycocalyx layer: results from a preliminary cross-sectional study

Introduction

Antiphospholipid syndrome (APS) is associated with greater atherothrombotic risk and endothelial dysfunction, suggesting that endothelial glycocalyx is impaired in this disease.

Objectives

The aim was to investigate the endothelial glycocalyx and the relationship between glycocalyx markers, endothelial dysfunction parameters and atherosclerotic markers in APS.

Methods

A total of 15 primary arterial APS patients and healthy controls were included in the study. Glycocalyx was assessed in both groups by sublingual sidestream dark field imaging and syndecan-1 plasma level. Endothelial function was evaluated by brachial artery flow-mediated dilatation (FMD) and early atherosclerosis by carotid intima media thickness (IMT). Thrombotic profile was also performed by measuring the plasma level of the tissue factor (TF).

Results

APS patients had significantly increased syndecan-1 plasma level 38.6 ± 5.0 pg/ml vs. 19.1 ± 3.5 pg/ml; p < 0.01 and a reduced glycocalyx thickness 0.26 ± 0.03 µm vs. 0.75 ± 0.07 µm; p < 0.01 compared with control. FMD was impaired in APS patients compared with control, 5.68% ± 0.42 vs. 8.29 ± 0.30, p < 0.01, respectively. IMT was significantly increased in APS patients compared with control, 0.52 ± 0.13 mm vs. 0.40 ± 0.06 mm, p < 0.01, respectively. Soluble TF, thiobarbituric acid-reactive substances levels were increased in the sera from APS patients compared with control.

Conclusions

This preliminary study supports, for the first time, that in APS patients endothelial glycocalyx is impaired, which could lead to thrombosis, endothelial dysfunction and early atherosclerosis.

[Which place of antiphosphatidylethanolamine antibodies research in seronegative antiphospholipid syndrome suspicion?]

PURPOSE

Antiphospholipid syndrome (APS) is a clinico-biological syndrome, which associates vascular injury and persisting antiphospholipid antibodies (aPL). Patients with clinical symptoms of APS but without aPL are defined as "seronegative APS" (SNAPS). The aim of this study was to evaluate antiphosphatidylethanolamine antibody (aPE) investigation in patients with SNAPS suspicion.

METHODS

This retrospective study was conducted in patients with SNAPS suspicion. A homemade enzyme-linked immunosorbent assay (ELISA) was used to search for aPE. The results of this homemade method were compared with those from a global screening ELISA.

RESULTS

Two hundred twenty-eight patients with SNAPS suspicion were included. Among them, 58.3% had a thrombotic event. The homemade ELISA found positive persisting aPE in 23 patients (10%): 15 with a thrombotic event, 6 with obstetrical morbidity and 2 with a combined event. The global screening ELISA was positive in only 11 of these 23 patients (47.8%).

CONCLUSION

These results suggest the implication of aPE in SNAPS.

[Agranulocytosis related to fluindione: A case report]

INTRODUCTION

While in most countries warfarin is the preferred anti-vitamin K, fluindione, a molecule with a prolonged half-life remains largely prescribed in France. Some of its side effects, including immuno-allergic complications, remain poorly understood.

CASE REPORT

A 77-year-old woman presented with a febrile severe neutropenia of immunoallergic mechanism with a favourable outcome associated with fluindione, introduced 25 days earlier for the treatment of atrial fibrillation.

CONCLUSION

This rare side effect is a reminder of the importance of biological monitoring in the first weeks following the introduction of fluindione and key diagnostic elements and therapeutic aspects of iatrogenic agranulocytosis.

[Usefulness of assessing hydration status in elderly patients over 70 years with suspected deep vein thrombosis]

INTRODUCTION

Venous thromboembolism and dehydration are frequent conditions in elderly. The objective of this study was to assess the prevalence of dehydration in patients aged over 70 years suspected of deep vein thrombosis (DVT).

METHODS

This is a prospective observational study that included patients aged over 70 years and suspected of deep vein thrombosis. Clinical and biological dehydration was diagnosed on the presence of a skin fold, a weight loss≥5%, a thirst, a plasmatic osmolality>295 mOsm/L or blood urea nitrogen/creatinine ratio>20.

RESULTS

One hundred and forty-four patients (mean age 81.8±5.8 years) were included. A diagnosis of DVT was retained in 97 patients. Clinical dehydration was not more frequent in the DVT+ group (37.2% vs 35.1%). At baseline, 69.1% of DVT+ patients and 53.2% of DVT- patients had a plasma osmolality greater than 295 mosm/L (NS). BUN/creatinine ratio greater than 20 was found in 58.8% of DVT+ patients and 72.3% of DVT- patients (NS). Clinical and biological dehydration was present in 28.6% of DVT+ patients and in 33.3% of DVT- patients (NS). The positive predictive value of the Wells score≥3 was 86.5%, and negative predictive value of a Wells score≤0 was 85%.

CONCLUSION

The presence of dehydration does not appear predictive of the occurrence of DVT and does not influence the statistical performance of the Wells score in elderly patients.

[Assessment of endothelial function in autoimmune diseases]

Numerous autoimmune-inflammatory rheumatic diseases have been associated with accelerated atherosclerosis or other types of vasculopathy leading to an increase in cardiovascular disease incidence. In addition to traditional cardiovascular risk factors, endothelial dysfunction is an important early event in the pathogenesis of atherosclerosis, contributing to plaque initiation and progression. Endothelial dysfunction is characterized by a shift of the actions of the endothelium toward reduced vasodilation, a proinflammatory and a proadhesive state, and prothrombic properties. Therefore, assessment of endothelial dysfunction targets this vascular phenotype using several biological markers as indicators of endothelial dysfunction. Measurements of soluble adhesion molecules (ICAM-1, VCAM-1, E-selectin), pro-thrombotic factors (thrombomodulin, von Willebrand factor, plasminogen activator inhibitor-1) and inflammatory cytokines are most often performed. Regarding the functional assessment of the endothelium, the flow-mediated dilatation of conduit arteries is a non-invasive method widely used in pathophysiological and interventional studies. In this review, we will briefly review the most relevant information upon endothelial dysfunction mechanisms and explorations. We will summarize the similarities and differences in the biological and functional assessments of the endothelium in different autoimmune diseases.

[Uncommon manifestation revealing sarcoidosis]

INTRODUCTION

Bilateral hilar lymphadenopathy, with or without lung parenchymal infiltrates, is the most common radiographic finding in patients with sarcoidosis. Atypical pulmonary findings have been uncommonly reported and include multiple large lung nodules, cavitation, lobar collapse, pleural effusions or pneumothorax.

OBSERVATION

We report a 21-year-old non caucasian patient who presented with pulmonary nodular infiltration and sinonasal involvement revealing sarcoidosis. Thoracic and sinus computed tomographic scan showed both multiple excavated large lung nodules and micronodules, hilar lymphadenopathy and sinus thickening. Laboratory studies disclosed elevated angiotensin converting enzyme serum level (120UI/L). Outcome was favorable after institution of corticosteroids (at an initial dose of prednisone of 1mg/kg/day); at eight-month-follow-up, the patient was asymptomatic, while receiving prednisone 22.5mg/day.

CONCLUSION

In patients exhibiting unusual pulmonary manifestations, diagnosis of sarcoidosis relies on compatible clinical signs, evidence of non-caseating granulomas, and exclusion of underlying conditions including infections, malignancy and other granulomatous diseases (Wegener disease, pneumoconiosis).

Diversity of Colombian strains of Bacillus thuringiensis with insecticidal activity against dipteran and lepidopteran insects

AIM

To evaluate the genetic and molecular diversity and insecticidal activity of Bacillus thuringiensis isolates from all the natural regions of Colombia.

METHODS AND RESULTS

A total of 445 isolates from a collection of B. thuringiensis were characterized. The parasporal crystal morphology that was most abundant was bipyramidal (60%). Almost 10% of the isolates were toxic to Spodoptera frugiperda and 5.6% against Culex quinquefasciatus larvae. cry gene content determined by PCR indicated that 10.6% of the isolates contained cry1 genes and 1.1% contained cry2, cry4 or cry11 genes. Protein content of the parasporal crystal was determined by SDS-PAGE; 25 and 18 different protein profiles were found in isolates active against S. frugiperda and C. quinquefasciatus, respectively.

CONCLUSIONS

Bacillus thuringiensis presents great genetic and molecular diversity even in isolates from the same soil sample. Moreover, the diversity and activity of the isolates might have a relationship with the geographical origin of the samples.

SIGNIFICANCE AND IMPACT OF THE STUDY

The results obtained here indicate that some of the B. thuringiensis isolates characterized in this study are potential control agents that could be used in programmes against mosquitoes and S. frugiperda.

Distribution and characterization of Bacillus thuringiensis on the phylloplane of species of piper (Piperaceae) in three altitudinal levels

Bacillus thuringiensis is found naturally on the phylloplane. In this study 35 samples from 13 species of the genus Piper (Piperaceae) were collected from three altitudinal levels located between 1800 and 2900 m above sea level in the Colombian Andean forest of Central Cordillera. Two hundred and fifty-six isolates of B. thuringiensis were obtained from 74% of the samples studied. B. thuringiensis index (number of isolates of B. thuringiensis/number of isolates of sporulated bacilli) was 0.2. The isolates were characterized by crystal morphology, the presence of cry genes by PCR, and toxicity against insects. Fifty-five percent of the isolates found presented bipyramidal-crystal morphology, and 42% had round-crystal morphology. Seventy percent of the isolates amplified cry1 [cry one] genes (generally toxic to lepidopterans); 41.4% amplified cry4 and/or cry11 [cry eleven] genes (generally toxic to dipterans), and none of the isolates amplified cry3 genes (generally toxic to coleopterans). The most abundant genotype of cry genes (54.7% of the total) was cry1Aa, cry1Ab, cry1Ac, cry1Ad, and cry1B. From the total isolates found, 7.8% presented both cry1 and cry11 genes, and five isolates (2.0%) harbored cry1, cry4, and cry11 genes; all these isolates were toxic to Culex quinquefasciatus (Diptera) but not to Spodoptera frugiperda (Lepidoptera). To our knowledge, these genotypes have not been previously reported. Overall, almost 60% of the isolates were toxic to S. frugiperda, and a little more than 40% of the isolates were toxic to C. quinquefasciatus. The populations of viable vegetative cells and spores per unit area were estimated and studied statistically. No significant differences in the number of B. thuringiensis isolates per cm2 of leaf among the three altitudinal levels were found, nor were they found among the different Piper species evaluated. This study increases the knowledge of the ecology of B. thuringiensis.

Genetic evolution in the metastatic progression of human pancreatic cancer studied by CGH

Metastases are thought to be derived from emerging clones within primary tumors. Although the concept of the clonal evolution of cancer is well defined, the genetic grounds and significance of this process in human cancer progression are still poorly understood. To gain insight into the genetic basis and clonal evolution underlying the metastatic progression of human pancreatic cancer in vivo, we analyzed by comparative genomic hybridization (CGH) chromosomal imbalances in seven metastases originated in nude mice and their three corresponding orthotopically xenografted human pancreatic tumors. All metastases were found to be closely related to the corresponding orthotopic implant, adding many additional changes to the already altered copy number profile of the pancreatic tumors. Recurrent metastasis-specific alterations included gains at 16cen-q22 and 17q21-qter. CGH results from paired specimens strongly suggest that the majority of additional genetic alterations present in metastases are likely to be present in subclones in the primary tumor.

DNA copy number changes and evaluation of MYC, IGF1R, and FES amplification in xenografts of pancreatic adenocarcinoma

We analyzed eight samples of xenografted human pancreatic tumors and two metastases developed in mice by comparative genomic hybridization (CGH). The most recurrent changes were: gains on chromosomes 8 (8q24-qter; 7/8 cases), 15 (15q25-q26; 6/8 cases), 16 (16p in 6/8 cases; 16q in 5/8 cases), 20 (20q; 6/8 cases), and 19 (19q; 5/8 cases); and losses on chromosomes 18 (18q21; 6/8 cases), 6 (6q16-q21 and 6q24-qter; 5/8 cases each), and 9 (9p23-pter; 5/8 cases). The two metastases maintained the aberrations of the original pancreatic tumor plus gain of 11q12-q13 and 22q. Loss of heterozygosity analysis was carried out for 10p14-pter, a region that was lost in 3/8 samples. All of them presented allelic imbalance for all the informative loci. Fluorescence in situ hybridization and Southern analysis were performed to test some candidate oncogenes in 8q24 (MYC) and 15q25-qter (IGF1R and FES). Two of seven tumors showed high-level amplification of MYC relative to the centromere (> 3-fold), another two tumors had low-level amplification (1.5- to 3.0-fold), and one displayed 5.5 MYC signals/cell. In relation to the FES gene, low-level amplification was found in three tumors. Southern analysis showed five cases with a low-level amplification of IGF1R. Our data suggest that either few extra gene copies may be enough for cancer progression or other genes located in these regions are responsible for the amplifications found by CGH.

Clinical correlations of genetic changes by comparative genomic hybridization in Ewing sarcoma and related tumors

Our previous comparative genomic hybridization (CGH) study of Ewing sarcoma and related tumors showed that DNA sequence copy number increases of 1q21-q22 and of chromosomes 8 and 12 were associated with trends toward poor survival (Armengol et al., Br J Cancer 1997, 75, 1403-1409). These trends were not statistically significant. In the present study, we analyzed 28 primary Ewing sarcomas and related tumors by CGH to study whether these (or other) changes have prognostic value in these tumors. Twenty-one tumors (75%) had changes with a mean of 1.9 changes per tumor. The most frequent aberration was gain of chromosome 8 in 10 tumors (36%). Five tumors (18%) had copy number increases at 1q21-22 and 5 had gain of 7q. Copy number increase of 6p21.1-pter, gain of chromosome 12, and loss of 16q were seen in 11%. Copy number increases of 1q21-q22 and of chromosomes 8 and 12 were associated with trends toward worse outcome, but the differences did not reach statistical significance. A novel finding is the association of copy number increase at 6p with worse distant disease-free (P = 0.04) and overall survival (P = 0.004). To confirm this finding and to see whether copy number increases of 1q21-q22 and of chromosomes 8 and 12 have definite prognostic value, a larger number of cases needs to be studied.

Comparative genomic hybridization study on pooled DNAs from tumors of one clinical-pathological entity

Comparative genomic hybridization (CGH) was performed using DNAs pooled from numerous specimens from tumor categories studied case-by-case. The series of six DNA pools consisted of 28 diffuse centroblastic lymphomas (DCL), 28 gastrointestinal stromal tumors (GIST), 21 primary chondrosarcomas (CS), 17 samples from the Ewing family of tumors (ET), 14 liposarcomas (LS), and 14 mesotheliomas (MS). Losses and gains present in at least 50% of the individual specimens were always detected in the pooled DNAs. The loss of the whole p-arm of chromosome 1 was observed even when the affected proportion of individual specimens was only 25%. Gains were also detected at frequencies lower than 50%, but with a high-level amplification in one or more specimens. In conclusion, the present pooled DNA study revealed the following changes: DCL had a gain at 18q22-qter; GIST had losses at 14 and 22q12, and gains at 5p, 8q22-24, 17q22-qter, and 19q13; ET had gains at 1q and 8q13-qter; LS had gains at 1q21-25 and 12q; and MS had a loss at 9p22-pter. No changes were observed in the CS DNA pool. The results from individual specimens also stressed the importance of these chromosomal regions to the tumorigenesis in the corresponding malignancies. This pooled DNA approach can thus be used for fast screening of recurrent DNA copy number in a specific tumor entity.

Recurrent gains of 1q, 8 and 12 in the Ewing family of tumours by comparative genomic hybridization

Comparative genomic hybridization (CGH) was used to detect copy number changes of DNA sequences in the Ewing family of tumours (ET). We analysed 20 samples from 17 patients. Fifteen tumours (75%) showed copy number changes. Gains of DNA sequences were much more frequent than losses, the majority of the gains affecting whole chromosomes or whole chromosome arms. Recurrent findings included copy number increases for chromosomes 8 (seven out of 20 samples; 35%), 1q (five samples; 25%) and 12 (five samples; 25%). The minimal common regions of these gains were the whole chromosomes 8 and 12, and 1q21-22. High-level amplifications affected 8q13-24, 1q and 1q21-22, each once. Southern blot analysis of the specimen with high-level amplification at 1q21-22 showed an amplification of FLG and SPRR3, both mapped to this region. All cases with a gain of chromosome 12 simultaneously showed a gain of chromosome 8. Comparison of CGH findings with cytogenetic analysis of the same tumours and previous cytogenetic reports of ET showed, in general, concordant results. In conclusion, our findings confirm that secondary changes, which may have prognostic significance in ET, are trisomy 8, trisomy 12 and a gain of DNA sequences in 1q.