Although many studies have reported cases of COVID-19 infection in transplant recipients, most of them only involve a small number of patients and narrow geographic areas. This study aims to investigate the clinical characteristics, morbidity, severity, and mortality of COVID-19 infection among solid organ transplant (SOT) recipients by meta-analysis.

We performed a literature search using the databases PubMed, Web of Science, and Google Scholar as of November 26, 2020. We included randomized controlled trials and cohort studies, excluding case reports and small case series (n < 10). The pooled incidence proportion and 95% confidence intervals (CI) were used to estimate the combined results of forty-seven studies were included for the meta-analysis. Heterogeneity was assessed using I2. Freeman-Tukey double arcsine transformation was used to stabilize the specific rate variance. Publication bias was using Egger's test.

The morbidity rate of COVID-19 in SOT recipients was 2.10% [95% CI 1.35-3.01], and the proportion of severe infection was 22.46% [95% CI 15.74-29.90]. The mortality rate was 17.38% [95% CI 13.72-21.34]. In the analysis by transplanted organ, the proportion of patients with severe infection was highest in recipients of two or more transplants 48.85% [95% CI 11.88-86.38]. The mortality rate was highest in lung transplant recipients 25.12% [95% CI 16.94-34.00]. The most common symptoms of COVID-19 in SOT recipients were fever (73.39%), cough (58.90%), and respiratory symptoms (45.77%).

SOT was a risk factor for worse COVID-19 outcomes, although the morbidity of COVID-19 in SOT recipients was not markedly higher than the general population. These results may change when our understanding of the disease progress.

We aimed to assess the short-term effectiveness of COVID-19 vaccines among immunocompromised patients to prevent laboratory-confirmed symptomatic COVID-19 infection.

Systematic review and meta-analysis. We calculated the pooled diagnostic odds ratio [DOR] (95% CI) for COVID-19 infection between immunocompromised patients and healthy people or those with stable chronic medical conditions. VE was estimated as 100% x (1-DOR). We also investigated the rates of developing anti-SARS-CoV-2 spike protein IgG between the 2 groups.

Twenty studies evaluating COVID-19 vaccine response, and four studies evaluating VE were included in the meta-analysis. The pooled DOR for symptomatic COVID-19 infection in immunocompromised patients was 0.296 (95% CI: 0.108-0.811) with an estimated VE of 70.4% (95% CI: 18.9%- 89.2%). When stratified by diagnosis, IgG antibody levels were much higher in the control group compared to immunocompromised patients with solid organ transplant (pOR 232.3; 95% Cl: 66.98-806.03), malignant diseases (pOR 42.0, 95% Cl: 11.68-151.03), and inflammatory rheumatic diseases (pOR 19.06; 95% Cl: 5.00-72.62).

We found COVID-19 mRNA vaccines were effective against symptomatic COVID-19 among the immunocompromised patients but had lower VE compared to the controls. Further research is needed to understand the discordance between antibody production and protection against symptomatic COVID-19 infection.

Immunocompromised (IC) patients are at higher risk of severe SARS-CoV-2 infection, morbidity, and mortality compared to the general population. They should be prioritized for primary prevention through vaccination. This study aimed to evaluate the efficacy of COVID-19 mRNA vaccines in IC patients through a systematic review and meta-analysis approach.

PubMed-MEDLINE, Scopus, and Web of Science were searched for original articles reporting the immunogenicity of two doses of mRNA COVID-19 vaccines in adult patients with IC condition between June 1, 2020 and September 1, 2021. Meta-analysis was performed using either random or fixed effect according to the heterogeneity of the studies. Subgroup analysis was performed to identify potential sources of heterogeneity.

A total of 26 studies on 3207 IC patients and 1726 healthy individuals were included. The risk of seroconversion in IC patients was 48% lower than those in controls (RR = 0.52 [0.42, 0.65]). IC patients with autoimmune conditions were 54%, and patients with malignancy were 42% more likely to have positive seroconversion than transplant recipients (P < 0.01). Subgroup meta-analysis based on the type of malignancy, revealed significantly higher proportion of positive seroconversion in solid organ compared to hematologic malignancies (RR = 0.88 [0.85, 0.92] vs. 0.61 [0.44, 0.86], P = 0.03). Subgroup meta-analysis based on type of transplantation (kidney vs. others) showed no statistically significant between-group difference of seroconversion (P = 0.55).

IC patients, especially transplant recipients, developed lower immunogenicity with two-dose of COVID-19 mRNA vaccines. Among patients with IC, those with autoimmune conditions and solid organ malignancies are mostly benefited from COVID-19 vaccination. Findings from this meta-analysis could aid healthcare policymakers in making decisions regarding the importance of the booster dose or more strict personal protections in the IC patients.

Since the start of the COVID-19 pandemic and consequent lockdowns, the use of telehealth interventions has rapidly increased both in the general population and among transplant recipients. Among pediatric transplant recipients, this most frequently takes the form of interventions on mobile devices, or mHealth, such as remote visits via video chat or phone, phone-based monitoring, and mobile apps. Telehealth interventions may offer the opportunity to provide care that minimizes many of the barriers of in-person care.

The present review followed the PRISMA guidelines. Sources up until October 2020 were initially identified through searches of PsycInfo® and PubMed® .

We identified ten papers that reported findings from adult interventions and five studies based in pediatrics. Eight of the adult publications stemmed from the same two trials; within the pediatric subset, this was the case for two papers. Studies that have looked at mHealth interventions have found high acceptability rates over the short run, but there is a general lack of data on long-term use.

The literature surrounding pediatric trials specifically is sparse with all findings referencing interventions that are in early stages of development, ranging from field tests to small feasibility trials. The lack of research highlights the need for a multi-center RCT that utilizes robust measures of medication adherence and other outcome variables, with longer-term follow-up before telehealth interventions should be fully embraced.

End-stage renal disease (ESRD) patients are amongst the vulnerable groups and thus prioritized in the Coronavirus disease-2019 vaccination programmes. However, this cohort was excluded from vaccine-trials and yet shares the same vaccination scheme with the general population. Here, we explore trends of immune response-proportions amongst ESRD patients on renal replacement therapy for up to 4 weeks post-vaccination completion with Pfizer/Moderna vaccines. From inception to 10 July 2021, we searched six online-databases for articles reporting humoral and cellular immune response proportions for up to 4 weeks post booster-vaccination. We pooled the responders' proportions by meta-analysis and conducted a meta-regression stratifying outcomes by significant confounders. Twenty-seven eligible studies reported 2789 ESRD patients. 1337, 1452 and 477 were on haemodialysis, received kidney transplantation, and healthy controls, respectively. Haemodialysis patients' proportions of humoral and cellular immune responses varied from 87.29% (80.77-93.81)-88.78% (86.76-90.80) and 62.86% (56.56, 69.17)-85.78% (78.99, 92.57), respectively, between first- and fourth-weeks. Kidney transplant patients' proportions of humoral and cellular immune responses ranged from 2.6% (0.06-13.48)-29.87% (27.68, 32.07) and 5.13% (0.63-17.3)-59.84% (54.57-65.10), respectively, between first- and fourth-weeks. All healthy controls maintained ≥93% proportions of both responses throughout the follow-up. Study design and country of study influenced the pooled response proportions. Conclusively, haemodialysis and kidney transplant patients have lower proportions of humoral and cellular immune responses than healthy controls. However, haemodialysis patients' response proportions improve, reaching near healthy-control levels by the fourth week. Kidney transplant patients' lower responses' proportions also improve but remain significantly lower than healthy controls throughout four-weeks. The "one-size-fits-all" vaccination scheme might be inadequate for kidney transplant patients.

Kidney transplant recipients and dialysis patients constitute a risk group for severe COVID-19. They are highly advised to get vaccinated according to the current guidelines. However, data on antibody response, cell responses and protection from events, and factors that might alter this response after a routine full series of vaccination remain incomplete for these populations. The aim of this article was to analyze the antibody responses after a full series of mRNA-based SARS-CoV-2 vaccination in kidney transplantation and dialysis patients and to define the factors that alter seroconversion status in these populations. In this systematic review, 18 studies investigating the antibody response to full vaccination with two doses of COVID-19 mRNA vaccines in hemodialysis, peritoneal dialysis, and kidney transplant patients were included. Kidney transplant and dialysis patients have a lower seroconversion rate after mRNA-based SARS-CoV-2 vaccination than the healthy population: 27.2% for kidney transplantation, 88.5% for dialysis patients while all healthy control in these studies seroconverted. Moreover, anti-S antibody titers were lower in seroconverted kidney transplantation or dialysis patients than in healthy control in all studies that assessed this variable. Older age and dialysis vintage, immunosuppressive or chemotherapy treatment, and lower serum albumin, white blood cell, lymphocyte and hemoglobin counts were associated with lower/no antibody response to vaccination. Dialysis patients and kidney transplant recipients have lower seroconversion rates after a full series of mRNA-based SARS-CoV-2 vaccination than the general population. Several factors are associated with an altered antibody response. A third dose could be considered in this patient group.

The COVID-19 pandemic has devastated the global community with nearly 4.9 million deaths as of October 2021. While organ transplant (OT) recipients (OTr) may be at increased risk for severe COVID-19 due to their chronic immunocompromised state, outcomes for OTr with COVID-19 remain disputed in the literature. This review will examine whether OTr with COVID-19 are at higher risk for severe illness and death than non-immunocompromised individuals.

MEDLINE (via Ovid and PubMed) and EMBASE (via Embase.com ) will be searched from December 2019 to October 2021 for observational studies (including cohort and case-control) that compare COVID-19 clinical outcomes in OTr to those in individuals without history of OT. The primary outcome of interest will be mortality as defined in each study, with possible further analyses of in-hospital mortality, 28 or 30-day mortality, and all-cause mortality versus mortality attributable to COVID-19. The secondary outcome of interest will be the severity of COVID-19 disease, most frequently defined as requiring intensive care unit admission or mechanical ventilation. Two reviewers will independently screen all abstracts and full-text articles. Potential conflicts will be resolved by a third reviewer and potentially discussion among all investigators. Methodological quality will be appraised using the Newcastle-Ottawa Scale. If data permit, we will perform random-effects meta-analysis with the Sidik-Jonkman estimator and the Hartung-Knapp adjustment for confidence intervals to estimate a summary measure of association between histories of transplant with each outcome. Potential sources of heterogeneity will be explored using meta-regression. Additional analyses will be conducted to explore the potential sources of heterogeneity (e.g., subgroup analysis) considering least minimal adjustment for confounders.

This rapid review will assess the available evidence on whether OTr diagnosed with COVID-19 are at higher risk for severe illness and death compared to non-immunocompromised individuals. Such knowledge is clinically relevant and may impact risk stratification, allocation of organs and healthcare resources, and organ transplantation protocols during this, and future, pandemics.

Open Science Framework (OSF) registration DOI: https://doi.org/10.17605/osf.io/4n9d7 .

The adverse impact of Coronavirus disease 2019 (COVID-19) on kidney function has been reported since the global pandemic. The burden of COVID-19 on kidney transplant recipients, however, has not been systematically analyzed. A systematic review and meta-analysis with a random-effect model was conducted to explore the rate of mortality, intensive care unit admission, invasive mechanical ventilation, acute kidney injury, kidney replacement therapy and graft loss in the adult kidney transplant population with COVID-19. Sensitivity analysis, subgroup analysis and meta-regression were also performed. Results: we demonstrated a pooled mortality rate of 21% (95% CI: 19-23%), an intensive care unit admission rate of 26% (95% CI: 22-31%), an invasive ventilation rate among those who required intensive care unit care of 72% (95% CI: 62-81%), an acute kidney injury rate of 44% (95% CI: 39-49%), a kidney replacement therapy rate of 12% (95% CI: 9-15%), and a graft loss rate of 8% (95% CI: 5-15%) in kidney transplant recipients with COVID-19. The meta-regression indicated that advancing age is associated with higher mortality; every increase in age by 10 years was associated with an increased mortality rate of 3.7%. Regional differences in outcome were also detected. Further studies focused on treatments and risk factor identification are needed.

Kidney transplantation recipients (KTR) with coronavirus disease 2019 (COVID-19) are at higher risk of death than general population. However, mortality risk factors in KTR are still not clearly identified. Our objective was to systematically analyze published evidence for risk factors associated with mortality in COVID-19 KTR. Electronic databases were searched for eligible studies on 1 August 2021. All prospective and retrospective studies of COVID-19 in KTR were considered eligible without language restriction. Since data in case reports and series could potentially be subsets of larger studies, only studies with ≥ 50 patients were included. Random-effects model meta-analysis was used to calculate weighted mean difference (WMD) and pooled odds ratio (OR) of factors associated with mortality. From a total 1,137 articles retrieved, 13 were included in the systematic review and meta-analysis comprising 4,440 KTR. Compared with survivors, non-survivors were significantly older (WMD 10.5 years, 95% CI 9.3-11.8). KTR of deceased donor were at higher risk of death (OR 1.73, 95% CI 1.10-2.74). Comorbidities including diabetes mellitus, cardiovascular disease, and active cancer significantly increased mortality risk. KTR with dyspnea (OR 5.68, 95% CI 2.11-15.33) and pneumonia (OR 10.64, 95% CI 3.37-33.55) at presentation were at higher mortality risk, while diarrhea decreased the risk (OR 0.61, 95% CI 0.47-0.78). Acute kidney injury was associated with mortality (OR 3.24, 95% CI 1.36-7.70). Inflammatory markers were significantly higher in the non-survivors, including C-reactive protein, procalcitonin, and interleukine-6. A number of COVID-19 mortality risk factors were identified from KTR patient characteristics, presenting symptoms, and laboratory investigations. KTR with these risk factors should receive more intensive monitoring and early therapeutic interventions to optimize health outcomes.