Your browser doesn't support javascript.
: 20 | 50 | 100
1 - 10 de 10
Open Forum Infect Dis ; 9(2): ofab632, 2022 Feb.
Article En | MEDLINE | ID: mdl-35103246

Population-level immune surveillance, which includes monitoring exposure and assessing vaccine-induced immunity, is a crucial component of public health decision-making during a pandemic. Serosurveys estimating the prevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) antibodies in the population played a key role in characterizing SARS-CoV-2 epidemiology during the early phases of the pandemic. Existing serosurveys provide infrastructure to continue immune surveillance but must be adapted to remain relevant in the SARS-CoV-2 vaccine era. Here, we delineate how SARS-CoV-2 serosurveys should be designed to distinguish infection- and vaccine-induced humoral immune responses to efficiently monitor the evolution of the pandemic. We discuss how serosurvey results can inform vaccine distribution to improve allocation efficiency in countries with scarce vaccine supplies and help assess the need for booster doses in countries with substantial vaccine coverage.

ERJ Open Res ; 8(1)2022 Jan.
Article En | MEDLINE | ID: mdl-35169585

Due to the large number of patients with severe coronavirus disease 2019 (COVID-19), many were treated outside the traditional walls of the intensive care unit (ICU), and in many cases, by personnel who were not trained in critical care. The clinical characteristics and the relative impact of caring for severe COVID-19 patients outside the ICU is unknown. This was a multinational, multicentre, prospective cohort study embedded in the International Severe Acute Respiratory and Emerging Infection Consortium World Health Organization COVID-19 platform. Severe COVID-19 patients were identified as those admitted to an ICU and/or those treated with one of the following treatments: invasive or noninvasive mechanical ventilation, high-flow nasal cannula, inotropes or vasopressors. A logistic generalised additive model was used to compare clinical outcomes among patients admitted or not to the ICU. A total of 40 440 patients from 43 countries and six continents were included in this analysis. Severe COVID-19 patients were frequently male (62.9%), older adults (median (interquartile range (IQR), 67 (55-78) years), and with at least one comorbidity (63.2%). The overall median (IQR) length of hospital stay was 10 (5-19) days and was longer in patients admitted to an ICU than in those who were cared for outside the ICU (12 (6-23) days versus 8 (4-15) days, p<0.0001). The 28-day fatality ratio was lower in ICU-admitted patients (30.7% (5797 out of 18 831) versus 39.0% (7532 out of 19 295), p<0.0001). Patients admitted to an ICU had a significantly lower probability of death than those who were not (adjusted OR 0.70, 95% CI 0.65-0.75; p<0.0001). Patients with severe COVID-19 admitted to an ICU had significantly lower 28-day fatality ratio than those cared for outside an ICU.

Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Article En | MEDLINE | ID: mdl-35058359

Allogeneic hematopoietic cell transplantation (HCT) provides effective treatment for hematologic malignancies and immune disorders. Monitoring of posttransplant complications is critical, yet current diagnostic options are limited. Here, we show that cell-free DNA (cfDNA) in blood is a versatile analyte for monitoring of the most important complications that occur after HCT: graft-versus-host disease (GVHD), a frequent immune complication of HCT, infection, relapse of underlying disease, and graft failure. We demonstrate that these therapeutic complications are informed from a single assay, low-coverage bisulfite sequencing of cfDNA, followed by disease-specific bioinformatic analyses. To inform GVHD, we profile cfDNA methylation marks to trace the cfDNA tissues-of-origin and to quantify tissue-specific injury. To inform infection, we implement metagenomic cfDNA profiling. To inform cancer relapse, we implement analyses of tumor-specific genomic aberrations. Finally, to detect graft failure, we quantify the proportion of donor- and recipient-specific cfDNA. We applied this assay to 170 plasma samples collected from 27 HCT recipients at predetermined timepoints before and after allogeneic HCT. We found that the abundance of solid-organ-derived cfDNA in the blood at 1 mo after HCT is predictive of acute GVHD (area under the curve, 0.88). Metagenomic profiling of cfDNA revealed the frequent occurrence of viral reactivation in this patient population. The fraction of donor-specific cfDNA was indicative of relapse and remission, and the fraction of tumor-specific cfDNA was informative of cancer relapse. This proof-of-principle study shows that cfDNA has the potential to improve the care of allogeneic HCT recipients by enabling earlier detection and better prediction of the complex array of complications that occur after HCT.

Cell-Free Nucleic Acids , DNA Fingerprinting , Graft vs Host Disease/diagnosis , Graft vs Host Disease/etiology , Hematopoietic Stem Cell Transplantation/adverse effects , Biomarkers , DNA Methylation , Disease Progression , Graft vs Host Disease/blood , Hematopoietic Stem Cell Transplantation/methods , Humans , Liquid Biopsy/methods , Organ Specificity/genetics , Postoperative Complications/blood , Postoperative Complications/diagnosis , Postoperative Complications/etiology , Recurrence , Transplantation, Homologous
Transpl Infect Dis ; 23(4): e13645, 2021 Aug.
Article En | MEDLINE | ID: mdl-34022099

As some of those who were lucky enough to have been mentored by Dr Francisco Marty in transplant infectious diseases, we stand with the larger medical community in mourning his untimely death and in commemorating him as a uniquely exceptional and talented physician, investigator, teacher, mentor, friend, artist, and human being.

Physicians , Humans , Male
CJC Open ; 3(7): 965-975, 2021 Jul.
Article En | MEDLINE | ID: mdl-33842874

BACKGROUND: Angiotensin receptor blockers (ARBs) and/or angiotensin-converting enzyme (ACE) inhibitors could alter mortality from coronavirus disease 2019 (COVID-19), but existing meta-analyses that combined crude and adjusted results may be confounded by the fact that comorbidities are more common in ARB/ACE inhibitor users. METHODS: We searched PubMed/MEDLINE/Embase for cohort studies and meta-analyses reporting mortality by preexisting ARB/ACE inhibitor treatment in hospitalized COVID-19 patients. Random effects meta-regression was used to compute pooled odds ratios for mortality adjusted for imbalance in age, sex, and prevalence of cardiovascular disease, hypertension, diabetes mellitus, and chronic kidney disease between users and nonusers of ARBs/ACE inhibitors at the study level during data synthesis. RESULTS: In 30 included studies of 17,281 patients, 22%, 68%, 25%, and 11% had cardiovascular disease, hypertension, diabetes mellitus, and chronic kidney disease. ARB/ACE inhibitor use was associated with significantly lower mortality after controlling for potential confounding factors (odds ratio 0.77 [95% confidence interval: 0.62, 0.96]). In contrast, meta-analysis of ARB/ACE inhibitor use was not significantly associated with mortality when all studies were combined with no adjustment made for confounders (0.87 [95% confidence interval: 0.71, 1.08]). CONCLUSIONS: ARB/ACE inhibitor use was associated with decreased mortality in cohorts of COVID-19 patients after adjusting for age, sex, cardiovascular disease, hypertension, diabetes, and chronic kidney disease. Unadjusted meta-analyses may not be appropriate for determining whether ARBs/ACE inhibitors are associated with mortality from COVID-19 because of indication bias.

INTRODUCTION: Les antagonistes des récepteurs de l'angiotensine (ARA) et/ou les inhibiteurs de l'enzyme de conversion de l'angiotensine (IECA) feraient varier la mortalité liée à la COVID-19, mais il est possible que les méta-analyses actuelles qui combinaient les résultats bruts et ajustés soient invalidées du fait que les comorbidités sont plus fréquentes chez les utilisateurs d'ARA/IECA. MÉTHODES: Nous avons effectué des recherches dans les bases de données PubMed/MEDLINE/Embase pour trouver des études de cohorte et des méta-analyses qui portent sur la mortalité associée à un traitement préexistant par ARA/IECA chez les patients hospitalisés atteints de la COVID-19. Nous avons utilisé la métarégression à effets aléatoires pour calculer les rapports de cotes regroupés de mortalité ajustés en fonction du déséquilibre de l'âge, du sexe, et de la prévalence des maladies cardiovasculaires, de l'hypertension, du diabète sucré et de l'insuffisance rénale chronique entre les utilisateurs et les non-utilisateurs d'ARA/IECA dans le cadre de l'étude durant la synthèse des données. RÉSULTATS: Dans les 30 études portant sur 17 281 patients, 22 %, 68 %, 25 % et 11 % avaient respectivement une maladie cardiovasculaire, de l'hypertension, le diabète sucré et de l'insuffisance rénale chronique. L'utilisation des ARA/IECA a été associée à une mortalité significativement plus faible après avoir tenu compte des facteurs confusionnels potentiels (rapport de cotes 0,77 [intervalle de confiance à 95 % : 0,62, 0,96]). En revanche, la méta-analyse sur l'utilisation des ARA/IECA n'a pas été associée de façon significative à la mortalité lorsque toutes les études ont été combinées sans ajustement sur les facteurs confusionnels (0,87 [intervalle de confiance à 95 % : 0,71, 1,08]). CONCLUSIONS: L'utilisation des ARA/IECA a été associée à la diminution de la mortalité au sein des cohortes de patients atteints de la COVID-19 après l'ajustement en fonction de l'âge, du sexe, des maladies cardiovasculaires, de l'hypertension, du diabète et de l'insuffisance rénale chronique. Les méta-analyses non ajustées peuvent ne pas permettre de déterminer si les ARA/IECA sont associés à la mortalité liée à la COVID-19 en raison du biais d'indication.

Med (N Y) ; 2(4): 411-422.e5, 2021 04 09.
Article En | MEDLINE | ID: mdl-33521749

BACKGROUND: Coronavirus disease 2019 (COVID-19) primarily affects the lungs, but evidence of systemic disease with multi-organ involvement is emerging. Here, we developed a blood test to broadly quantify cell-, tissue-, and organ-specific injury due to COVID-19. METHODS: Our test leverages genome-wide methylation profiling of circulating cell-free DNA in plasma. We assessed the utility of this test to identify subjects with severe disease in two independent, longitudinal cohorts of hospitalized patients. Cell-free DNA profiling was performed on 104 plasma samples from 33 COVID-19 patients and compared to samples from patients with other viral infections and healthy controls. FINDINGS: We found evidence of injury to the lung and liver and involvement of red blood cell progenitors associated with severe COVID-19. The concentration of cell-free DNA correlated with the World Health Organization (WHO) ordinal scale for disease progression and was significantly increased in patients requiring intubation. CONCLUSIONS: This study points to the utility of cell-free DNA as an analyte to monitor and study COVID-19. FUNDING: This work was supported by NIH grants 1DP2AI138242 (to I.D.V.), R01AI146165 (to I.D.V., M.P.C., F.M.M., and J.R.), 1R01AI151059 (to I.D.V.), K08-CA230156 (to W.G.), and R33-AI129455 to C.Y.C., a Synergy award from the Rainin Foundation (to I.D.V.), a SARS-CoV-2 seed grant at Cornell (to I.D.V.), a National Sciences and Engineering Research Council of Canada fellowship PGS-D3 (to A.P.C.), and a Burroughs-Wellcome CAMS Award (to W.G.). D.C.V. is supported by a Fonds de la Recherche en Sante du Quebec Clinical Research Scholar Junior 2 award. C.Y.C. is supported by the California Initiative to Advance Precision Medicine, and the Charles and Helen Schwab Foundation.

COVID-19 , Cell-Free Nucleic Acids , Virus Diseases , Humans , Methylation , SARS-CoV-2/genetics
Trials ; 22(1): 115, 2021 Feb 05.
Article En | MEDLINE | ID: mdl-33546734

OBJECTIVES: The aim of the RAAS-COVID-19 randomized control trial is to evaluate whether an upfront strategy of temporary discontinuation of renin angiotensin aldosterone system (RAAS) inhibition versus continuation of RAAS inhibition among patients admitted with established COVID-19 infection has an impact on short term clinical and biomarker outcomes. We hypothesize that continuation of RAAS inhibition will be superior to temporary discontinuation with regards to the primary endpoint of a global rank sum score. The global rank sum score has been successfully used in previous cardiovascular clinical trials. TRIAL DESIGN: This is an open label parallel two arm (1,1 ratio) randomized control superiority trial of approximately 40 COVID-19 patients who are on chronic RAAS inhibitor therapy. PARTICIPANTS: Adults who are admitted to hospital within the McGill University Health Centre systems (MUHC) including Royal Victoria Hospital (RVH), Montreal General Hospital (MGH) and Jewish General Hospital (JGH) and who are within 96 hours of COVID-19 diagnosis (confirmed via PCR on any biological sample) will be considered for the trial. Of note, the initial protocol to screen and enrol within 48 hours of COVID-19 diagnosis was extended through an amendment, to 96 hours to increase feasibility. Participants have to be 18 years or older and would have to be on RAAS inhibitors for at least a month to be considered eligible for the study. Additionally, RAAS inhibitors should not have been held for more than 48 hours before randomization. A list of inclusion and exclusion criteria can be found in the full protocol document. In order to prevent heart failure exacerbation, patients with reduced ejection fraction were excluded from the trial. Once a patient is admitted on the ward with a diagnosis of COVID-19, we will confirm with the treating physician if the participant is suitable for the RAAS-COVID trial and meets all the inclusion and exclusion criteria. If the patient is eligible and informed consent has been obtained we will collect data on sex, age, ethnicity, past medical history and list of medications (e.g. other anti-hypertensives or anticoagulants), for further analysis. INTERVENTION AND COMPARATOR: All the study participants will be randomized to a strategy of temporarily holding the RAAS inhibitor [intervention] versus continuing the RAAS inhibitor [continued standard of care]. Among participants who are randomized to the intervention arm, alternative guide-line directed anti-hypertensive medication will be provided to the treating physician team (detail in study protocol). In the intervention arm RAAS inhibitor will be withheld for a total of 7 days with the possibility of the withdrawn medication being initiated at any point after day 7 or on the day of discharge. The recommendation for re-initiating the withdrawn medication will be made to the treating physician. The re-initiation of these therapies are according to standard convention and follow-up as per Canadian guidelines. Additionally, the date of restarting the withdrawn medication or whether the medication was re-prescribed on discharge or not, will be collected. This will be used to conduct a sensitivity analysis. Furthermore, biomarkers such as troponin, c-reactive protein (CRP) and lymphocyte count will be assessed during the same time period. Samples will be collected on randomization, day 4 and day 7. MAIN OUTCOMES: PRIMARY ENDPOINT: In this study the primary end point is a global rank score calculated for all participants, regardless of treatment assignment ( score from 0 to 7). Please refer to table 4 in the full protocol. In the context of the current trial, it is estimated that death is the most meaningful endpoint, and therefore has the highest score ( score of 7). This is followed by admission to ICU, the need for mechanical ventilation etc. The lowest scores ( score of 1) are assigned to biomarker changes (e.g. change in troponin, change in CRP). This strategy has been used successfully in cardiovascular disease trials and therefore is applicable to the current trial. The primary endpoint for the present trial is assessed from baseline to day 7 (or discharge). Participants are ranked across the clinical and biomarker domains. Lower values indicate better health (or stability). Participants who died during the 7th day of the study will be ranked based on all events occurring before their death and also including the fatal event in the score. Next, participants who did not die but were transferred to ICU for invasive ventilation will be ranked based on all the events occurring before the ICU entry and also including the ICU admission in the score. Those participants who did not die were not transferred to ICU for invasive ventilation, will be ranked based on the subsequent outcomes. The mean rank score will then be compared between groups. In this scheme, a lower mean rank score indicates greater overall stability for participants. Secondary endpoints : The key secondary endpoints are the individual components of the primary components and include the following: death, transfer to ICU primarily for invasive ventilation, transfer to ICU for other indication, non-fatal MACE ( any of following, MI, stroke, acute HF, new onset Afib), length of stay > 4 days, development of acute kidney injury ( > 40% decline in eGFR or doubling of serum creatinine), urgent intravenous treatment for high blood pressure, 30% increase in baseline high sensitivity troponin, 30% increase in baseline BNP, increase in CRP to > 30% in 48 hours and lymphocyte count drop> 30%. We will also look at the World Health Organization (WHO) ordinal scale for clinical improvement (in COVID-19) in our data. In this scale death will be assigned the highest score of 8. Patients with no limitation of activity will be assigned a score of 1 which indicates overall more stability (3). Additionally, we will evaluate the potential effects of discontinuing RAAS inhibition on alternative schedules (longer/shorter than 7 days, intermittent discontinuation) using a mechanistic mathematical model of COVID-19 immunopathology calibrated to data collected from our patient cohort. In particular, we will assess the impact of alternative schedules on primary and secondary endpoints including increases to baseline CRP and lymphocyte counts. RANDOMIZATION: Participants will be randomized in a 1:1 ratio. Randomization will be performed within an electronic database system at the time of enrolment using a random number generator, an approach that has been successfully used in other clinical trials. Neither participant, study team, or treating team will be blinded to the intervention arm. BLINDING: This is an open label study with no blinding. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): The approximate number of participants required for this trial is 40 patients (randomized 1:1 to continuation versus discontinuation of RAAS inhibitors). This number was calculated based on previous rates of outcomes for COVID-19 in the literature (e.g. death, ICU transfer) and statistical power calculations. TRIAL STATUS: Protocol number: MP-37-2021-6641, Version 4: 01-10-2020. Trial start date September 1st 2020 and currently enrolling participants. Estimated end date for recruitment of participants : July 2021. Estimated end date for study completion: September 1st 2021. TRIAL REGISTRATION: Trial registration: : NCT04508985 , date of registration: August 11th , 2020 FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.

Angiotensin-Converting Enzyme 2/antagonists & inhibitors , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Antihypertensive Agents/therapeutic use , COVID-19/drug therapy , Patient Admission , Renin-Angiotensin System/drug effects , SARS-CoV-2/genetics , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/mortality , COVID-19/virology , Canada , Female , Follow-Up Studies , Humans , Intensive Care Units , Male , Middle Aged , Polymerase Chain Reaction , Randomized Controlled Trials as Topic , Treatment Outcome , Withholding Treatment , Young Adult
medRxiv ; 2020 Jul 29.
Article En | MEDLINE | ID: mdl-32766608

COVID-19 primarily affects the lungs, but evidence of systemic disease with multi-organ involvement is emerging. Here, we developed a blood test to broadly quantify cell, tissue, and organ specific injury due to COVID-19, using genome-wide methylation profiling of circulating cell-free DNA in plasma. We assessed the utility of this test to identify subjects with severe disease in two independent, longitudinal cohorts of hospitalized patients. Cell-free DNA profiling was performed on 104 plasma samples from 33 COVID-19 patients and compared to samples from patients with other viral infections and healthy controls. We found evidence of injury to the lung and liver and involvement of red blood cell progenitors associated with severe COVID-19. The concentration of cfDNA correlated with the WHO ordinal scale for disease progression and was significantly increased in patients requiring intubation. This study points to the utility of cell-free DNA as an analyte to monitor and study COVID-19.

Proc Natl Acad Sci U S A ; 116(37): 18738-18744, 2019 09 10.
Article En | MEDLINE | ID: mdl-31451660

High-throughput metagenomic sequencing offers an unbiased approach to identify pathogens in clinical samples. Conventional metagenomic sequencing, however, does not integrate information about the host, which is often critical to distinguish infection from infectious disease, and to assess the severity of disease. Here, we explore the utility of high-throughput sequencing of cell-free DNA (cfDNA) after bisulfite conversion to map the tissue and cell types of origin of host-derived cfDNA, and to profile the bacterial and viral metagenome. We applied this assay to 51 urinary cfDNA isolates collected from a cohort of kidney transplant recipients with and without bacterial and viral infection of the urinary tract. We find that the cell and tissue types of origin of urinary cfDNA can be derived from its genome-wide profile of methylation marks, and strongly depend on infection status. We find evidence of kidney and bladder tissue damage due to viral and bacterial infection, respectively, and of the recruitment of neutrophils to the urinary tract during infection. Through direct comparison to conventional metagenomic sequencing as well as clinical tests of infection, we find this assay accurately captures the bacterial and viral composition of the sample. The assay presented here is straightforward to implement, offers a systems view into bacterial and viral infections of the urinary tract, and can find future use as a tool for the differential diagnosis of infection.

Cell-Free Nucleic Acids/isolation & purification , Host-Pathogen Interactions/genetics , Metagenome/genetics , Metagenomics/methods , Postoperative Complications/diagnosis , Urinary Tract Infections/diagnosis , Bacterial Infections/diagnosis , Bacterial Infections/microbiology , Bacterial Infections/urine , Biomarkers/urine , Cell-Free Nucleic Acids/genetics , Cell-Free Nucleic Acids/urine , DNA Methylation/genetics , DNA, Bacterial/genetics , DNA, Bacterial/isolation & purification , DNA, Bacterial/urine , DNA, Viral/genetics , DNA, Viral/isolation & purification , DNA, Viral/urine , Diagnosis, Differential , Female , High-Throughput Nucleotide Sequencing , Host-Pathogen Interactions/immunology , Humans , Kidney/cytology , Kidney/immunology , Kidney/microbiology , Kidney/pathology , Kidney Failure, Chronic/surgery , Kidney Transplantation/adverse effects , Male , Neutrophil Infiltration/immunology , Postoperative Complications/immunology , Postoperative Complications/microbiology , Postoperative Complications/urine , Transplant Recipients , Urinary Bladder/cytology , Urinary Bladder/immunology , Urinary Bladder/microbiology , Urinary Bladder/pathology , Urinary Tract Infections/immunology , Urinary Tract Infections/microbiology , Urinary Tract Infections/urine , Virus Diseases/diagnosis , Virus Diseases/immunology , Virus Diseases/urine , Virus Diseases/virology
Pediatr Pulmonol ; 45(7): 661-6, 2010 Jul.
Article En | MEDLINE | ID: mdl-20575095

BACKGROUND: As Voriconazole is being used more frequently in cystic fibrosis (CF) patients, we aimed to describe the adverse events associated with voriconazole treatment in this population. METHODS: We performed a retrospective cohort study of all children with CF who received voriconazole between September 2006 and August 2008. RESULTS: Five of six CF patients receiving treatment developed photosensitivity, whereas all six patients reported visual disturbances. We report two clinical cases of particular interest: a 7-year-old boy developed striking erythema in the face and upper thorax; a 16-year-old girl who reported unexpected visual disturbances, including scotomas and tunneling vision. CONCLUSION: Significant adverse effects of voriconazole were noted in all treated CF patients. We speculate that this may be due to suppression of activity of hepatic enzymes involved in all transretinonic acid metabolism coupled with vitamin A supplementation in CF. Consideration should be given to reducing vitamin A supplementation during voriconazole treatment.

Antifungal Agents/adverse effects , Cystic Fibrosis/drug therapy , Photosensitivity Disorders/chemically induced , Pyrimidines/adverse effects , Triazoles/adverse effects , Vision Disorders/chemically induced , Vitamin A/metabolism , Adolescent , Antifungal Agents/therapeutic use , Child , Cohort Studies , Dietary Supplements , Female , Humans , Male , Photosensitivity Disorders/diagnosis , Pulmonary Aspergillosis/drug therapy , Pyrimidines/therapeutic use , Retrospective Studies , Treatment Outcome , Triazoles/therapeutic use , Vision Disorders/diagnosis , Voriconazole