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1.
Transplantation ; 107(5): 1124-1135, 2023 05 01.
Article in English | MEDLINE | ID: covidwho-2222974

ABSTRACT

BACKGROUND: The effectiveness of vaccines against the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) B.1.1.529 Omicron variant in immunosuppressed solid organ and islet transplant (SOT) recipients is unclear. METHODS: National registries in England were linked to identify SARS-CoV-2 positive tests, noninjury hospitalization within 14 d, and deaths within 28 d between December 7, 2020, and March 31, 2022 in adult SOT recipients. Incidence rate ratios (IRRs) for infection, and hospitalization or death, were adjusted for recipient demographics and calendar month for the Omicron-dominant period (December 20, 2021, to March 31, 2022). Mortality risk following SARS-CoV-2 infection was adjusted for recipient demographics and dominant variant using a Cox proportional-hazards model for the entire time period. RESULTS: During the Omicron-dominant period, infection IRRs (95% confidence intervals) were higher in those receiving 2, 3, and 4 vaccine doses than in unvaccinated patients (1.25 [1.08-1.45], 1.46 [1.28-1.67], and 1.79 [1.54-2.06], respectively). However, hospitalization or death IRRs during this period were lower in those receiving 3 or 4 vaccine doses than in unvaccinated patients (0.62 [0.45-0.86] and 0.39 [0.26-0.58], respectively). Risk-adjusted analyses for deaths after SARS-CoV-2 infection between December 7, 2020, and March 31, 2022, found hazard ratios (95% confidence intervals) of 0.67 (0.46-0.98), 0.46 (0.30-0.69), and 0.18 (0.09-0.35) for those with 2, 3, and 4 vaccine doses, respectively, when compared with the unvaccinated group. CONCLUSIONS: In immunosuppressed SOT recipients, vaccination is associated with incremental, dose-dependent protection against hospitalization or death after SARS-CoV-2 infection, including against the Omicron variant.


Subject(s)
COVID-19 , SARS-CoV-2 , Adult , Humans , Vaccine Efficacy , Retrospective Studies , Transplant Recipients , COVID-19/epidemiology , COVID-19/prevention & control , England/epidemiology
2.
Medicine ; 2023.
Article in English | ScienceDirect | ID: covidwho-2211165

ABSTRACT

Individuals with kidney failure face a future requiring long-term treatment with either dialysis or renal transplantation. Renal transplantation is the preferred form of renal replacement therapy, and is associated with a better quality of life, and usually increased longevity. Unfortunately, owing to excessive co-morbidities, only 30% of patients who develop end-stage renal failure are fit enough for transplantation. Over 90% of kidney transplants still function after 1 year, and most function for >15 years. Improvements in transplant outcomes are attributable to advances in histocompatibility testing, organ procurement, organ preservation, surgical techniques and perioperative care. Long-term outcomes have shown only minor improvements over the last two decades, although this should be considered in the context of deteriorating organ quality as older deceased donors with increasing co-morbidity are used more often to satisfy the need for donor organs. An overall increase in deceased donor numbers has boosted transplant activity in the UK, and it is hoped this will continue with the adoption of the ‘opt-out' consent system. Living donor activity remains stable, but the use of non-directed altruistic donation and the living donor exchange scheme have reduced the need for higher immunological risk incompatible transplantation. The COVID-19 pandemic has reduced transplant rates globally, although national transplant systems are now recovering.

3.
Transplantation ; 106(9): 1824-1830, 2022 09 01.
Article in English | MEDLINE | ID: covidwho-1931999

ABSTRACT

BACKGROUND: The emergence and attendant mortality of vaccine-induced immune thrombocytopenia and thrombosis (VITT) as a consequence of vaccination against severe acute respiratory syndrome coronavirus 2 have resulted in some patients with VITT being considered as deceased organ donors. Outcomes after kidney transplantation in this context are poorly described. Because the disease seems to be mediated by antiplatelet factor 4 antibodies, there is a theoretical risk of transmission via passenger leukocytes within the allograft. METHODS: We analyzed the experience of kidney transplantation from donors with VITT in the United Kingdom between January and June 2021. We followed-up all recipients of kidney-only transplants from donors with VITT to detect major postoperative complications or features of disease transmission and assess graft survival and function. RESULTS: There were 16 kidney donors and 30 single kidney transplant recipients in our study period. Of 11 preimplantation biopsies, 4 showed widespread glomerular microthrombi. After a median of 5 mo, patient and graft survival were 97% and 90%, respectively. The median 3-mo estimated glomerular filtration rate was 51 mL/min/1.73 m 2 . Two recipients had detectable antiplatelet factor 4 antibodies but no evidence of clinical disease after transplantation. Major hemorrhagic complications occurred in 3 recipients, all of whom had independent risk factors for bleeding, resulting in the loss of 2 grafts. The involvement of VITT could not be completely excluded in one of these cases. CONCLUSIONS: The UK experience to date shows that favorable outcomes are possible after kidney transplantation from donors with VITT but highlights the need for ongoing vigilance for donor-related complications in these patients.


Subject(s)
COVID-19 , Kidney Transplantation , Purpura, Thrombocytopenic, Idiopathic , Thrombosis , Vaccines , Graft Survival , Humans , Kidney Transplantation/methods , Purpura, Thrombocytopenic, Idiopathic/etiology , Retrospective Studies , Thrombosis/etiology , Tissue Donors
6.
Transplantation ; 106(3): 436-446, 2022 03 01.
Article in English | MEDLINE | ID: covidwho-1604080

ABSTRACT

BACKGROUND: The clinical effectiveness of vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in immunosuppressed solid organ and islet transplant (SOT) recipients is unclear. METHODS: We linked 4 national registries to retrospectively identify laboratory-confirmed SARS-CoV-2 infections and deaths within 28 d in England between September 1, 2020, and August 31, 2021, comparing unvaccinated adult SOT recipients and those who had received 2 doses of ChAdOx1-S or BNT162b2 vaccine. Infection incidence rate ratios were adjusted for recipient demographics and calendar month using a negative binomial regression model, with 95% confidence intervals. Case fatality rate ratios were adjusted using a Cox proportional hazards model to generate hazard ratio (95% confidence interval). RESULTS: On August 31, 2021, it was found that 3080 (7.1%) were unvaccinated, 1141 (2.6%) had 1 vaccine dose, and 39 260 (90.3%) had 2 vaccine doses. There were 4147 SARS-CoV-2 infections and 407 deaths (unadjusted case fatality rate 9.8%). The risk-adjusted infection incidence rate ratio was 1.29 (1.03-1.61), implying that vaccination was not associated with reduction in risk of testing positive for SARS-CoV-2 RNA. Overall, the hazard ratio for death within 28 d of SARS-CoV-2 infection was 0.80 (0.63-1.00), a 20% reduction in risk of death in vaccinated patients (P = 0.05). Two doses of ChAdOx1-S were associated with a significantly reduced risk of death (hazard ratio, 0.69; 0.52-0.92), whereas vaccination with BNT162b2 was not (0.97; 0.71-1.31). CONCLUSIONS: Vaccination of SOT recipients confers some protection against SARS-CoV-2-related mortality, but this protection is inferior to that achieved in the general population. SOT recipients require additional protective measures, including further vaccine doses, antiviral drugs, and nonpharmaceutical interventions.


Subject(s)
COVID-19 , SARS-CoV-2 , Adult , BNT162 Vaccine , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines/adverse effects , ChAdOx1 nCoV-19 , Humans , RNA, Viral , Retrospective Studies , Transplant Recipients
10.
African Journal of Science, Technology, Innovation & Development ; : 1-9, 2021.
Article in English | Academic Search Complete | ID: covidwho-1328569

ABSTRACT

According to the Solow paradox, the impact of the computer age can be seen everywhere but in the productivity statistics. Despite much debate about productivity gains promised by technologies associated with the ‘fourth industrial revolution,’ these are largely yet to materialise. Paradoxically, not only has there been a global productivity growth slowdown but also a decline in research and development (R&D) productivity: a ‘burden of knowledge’ effect. Given the potentially catastrophic costs of research failure and the inability of the scientific discovery system to anticipate fully and find a solution to the coronavirus pandemic, the purpose of this paper is to apply a detailed conceptual review methodology to understand better the fundamental causes of the global productivity growth slowdown. Challenging prevailing assumptions in the literature, the original contribution of the paper is a theoretical analysis that suggests a root cause of the global production growth slowdown may be a burden of knowledge effect associated with innovation failure. A causal ordering of relevant causes is discussed, and hypotheses are derived. Implications are derived for research management, and for policy regarding how a decline in global productivity growth might be arrested by remedying the burden of knowledge effect. [ABSTRACT FROM AUTHOR] Copyright of African Journal of Science, Technology, Innovation & Development is the property of Routledge and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

13.
Am J Transplant ; 20(11): 3008-3018, 2020 11.
Article in English | MEDLINE | ID: covidwho-780678

ABSTRACT

Patients waitlisted for and recipients of solid organ transplants (SOT) are perceived to have a higher risk of contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and death; however, definitive epidemiological evidence is lacking. In a comprehensive national cohort study enabled by linkage of the UK transplant registry and Public Health England and NHS Digital Tracing services, we examined the incidence of laboratory-confirmed SARS-CoV-2 infection and subsequent mortality in patients on the active waiting list for a deceased donor SOT and recipients with a functioning SOT as of February 1, 2020 with follow-up to May 20, 2020. Univariate and multivariable techniques were used to compare differences between groups and to control for case-mix. One hundred ninety-seven (3.8%) of the 5184 waitlisted patients and 597 (1.3%) of the 46 789 SOT recipients tested positive for SARS-CoV-2. Mortality after testing positive for SARS-CoV-2 was 10.2% (20/197) for waitlisted patients and 25.8% (154/597) for SOT recipients. Increasing recipient age was the only variable independently associated with death after positive SARS-CoV-2 test. Of the 1004 transplants performed in 2020, 41 (4.1%) recipients have tested positive for SARS-CoV-2 with 8 (0.8%) deaths reported by May 20. These data provide evidence to support decisions on the risks and benefits of SOT during the coronavirus disease 2019 pandemic.


Subject(s)
COVID-19/epidemiology , Organ Transplantation , Pandemics , Registries , SARS-CoV-2 , Tissue Donors , Transplant Recipients , Adolescent , Adult , Child , Child, Preschool , England/epidemiology , Female , Humans , Infant , Infant, Newborn , Male , Retrospective Studies , Risk Factors , Survival Rate/trends , Waiting Lists/mortality , Young Adult
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