Impact of COVID-19 in solid organ transplant recipients

The coronavirus disease 2019 (COVID-19) pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) exploded onto the world stage in early 2020. The impact on solid organ transplantation (SOT) has been profound affecting potential donors, candidates, and recipients. Importantly, decreased donations and the pressure of limited resources placed on health care by the pandemic also disrupted transplant systems. We address the impact of COVID-19 on organ transplantation globally and review current understanding of the epidemiology, outcomes, diagnosis, and treatment of COVID-19 in SOT recipients.     

Sex and organ-specific risk of major adverse renal or cardiac events in solid organ transplant recipients with COVID-19

While older males are at the highest risk for poor coronavirus disease 2019 (COVID-19) outcomes, it is not known if this applies to the immunosuppressed recipient of a solid organ transplant (SOT), nor how the type of allograft transplanted may impact outcomes. In a cohort study of adult (>18 years) patients testing positive for COVID-19 (January 1, 2020-June 21, 2021) from 56 sites across the United States identified using the National COVID Cohort Collaborative (N3C) Enclave, we used multivariable Cox proportional hazards models to assess time to MARCE after COVID-19 diagnosis in those with and without SOT. We examined the exposure of age-stratified recipient sex overall and separately in kidney, liver, lung, and heart transplant recipients. 3996 (36.4%) SOT and 91 646 (4.8%) non-SOT patients developed MARCE. Risk of post-COVID outcomes differed by transplant allograft type with heart and kidney recipients at highest risk. Males with SOT were at increased risk of MARCE, but to a lesser degree than the non-SOT cohort (HR 0.89, 95% CI 0.81–0.98 for SOT and HR 0.61, 95% CI 0.60–0.62 for non-SOT [females vs. males]). This represents the largest COVID-19 SOT cohort to date and the first-time sex-age–stratified and allograft-specific COVID-19 outcomes have been explored in those with SOT.     

Liver transplantation from active COVID-19 donors: A lifesaving opportunity worth grasping?

COVID-19 pandemic dramatically impacted transplantation landscape. Scientific societies recommend against the use of donors with active SARS-CoV-2 infection. Italian Transplant Authority recommended to test recipients/donors for SARS-CoV-2-RNA immediately before liver transplant (LT) and, starting from November 2020, grafts from deceased donors with active SARS-CoV-2 infection were allowed to be considered for urgent-need transplant candidates with active/resolved COVID-19. We present the results of the first 10 LTs with active COVID-19 donors within an Italian multicenter series. Only two recipients had a positive molecular test at LT and one of them remained positive up to 21 days post-LT. None of the other eight recipients was found to be SARS-CoV-2 positive during follow-up. IgG against SARS-CoV-2 at LT were positive in 80% (8/10) of recipients, and 71% (5/7) showed neutralizing antibodies, expression of protective immunity related to recent COVID-19. In addition, testing for SARS-CoV-2 RNA on donors’ liver biopsy at transplantation was negative in 100% (9/9), suggesting a very low risk of transmission with LT. Immunosuppression regimen remained unchanged, according to standard protocol. Despite the small number of cases, these data suggest that transplanting livers from donors with active COVID-19 in informed candidates with SARS-CoV-2 immunity, might contribute to safely increase the donor pool.

     

Navigating Kidney Transplantation in the Early Phase of Coronavirus Disease 2019: Screening Patients With Reverse Transcriptase Polymerase Chain Reaction and Low-Radiation-Dose Chest Computed Tomography

BackgroundThe coronavirus disease 2019 (COVID-19) pandemic of 2020 changed organ transplantation. All elective cases at our institution were postponed for approximately 3 months. Centers for Medicare and Medicaid Services considers organ transplant surgery a Tier 3b case, along with other high acuity procedures, recommending no postponement. Our transplant program collaborated with our transplant infectious disease colleagues to create a protocol that would ensure both patient and staff safety during these unprecedented times.MethodsThe living donor program was electively placed on hold until we had the proper protocols in place. Preoperative COVID-19 testing was required for all recipients and living donors. All patients underwent a rapid nasopharyngeal swab test. After testing negative by nasopharyngeal swab, recipients also underwent a low-radiation-dose computed tomography scan to rule out any radiographic changes suggestive of a COVID-19 infection.ResultsWe performed 8 living donor and 9 deceased donor kidney transplants. In comparison, we performed 10 living donor and 4 deceased donor transplants during the same time period in the previous year. Our testing protocol enabled efficient use of all suitable organs offered during the viral pandemic. No recipients or living donors tested positive or developed COVID-19.ConclusionsCreation of a viral testing protocol, developed in conjunction with our infectious disease team, permitted kidney transplantation to be performed safely, and the number of deceased donor transplants increased considerably without adversely affecting our outcomes.     

Changes in humoral immune response after SARS-CoV-2 infection in liver transplant recipients compared to immunocompetent patients

The protective capacity and duration of humoral immunity after SARS-CoV-2 infection are not yet understood in solid organ transplant recipients. A prospective multicenter study was performed to evaluate the persistence of anti-nucleocapsid IgG antibodies in liver transplant recipients 6 months after coronavirus disease 2019 (COVID-19) resolution. A total of 71 liver transplant recipients were matched with 71 immunocompetent controls by a propensity score including variables with a well-known prognostic impact in COVID-19. Paired case–control serological data were also available in 62 liver transplant patients and 62 controls at month 3 after COVID-19. Liver transplant recipients showed a lower incidence of anti-nucleocapsid IgG antibodies at 3 months (77.4% vs. 100%, p < .001) and at 6 months (63.4% vs. 90.1%, p < .001). Lower levels of antibodies were also observed in liver transplant patients at 3 (p = .001) and 6 months (p < .001) after COVID-19. In transplant patients, female gender (OR = 13.49, 95% CI: 2.17–83.8), a longer interval since transplantation (OR = 1.19, 95% CI: 1.03–1.36), and therapy with renin–angiotensin–aldosterone system inhibitors (OR = 7.11, 95% CI: 1.47–34.50) were independently associated with persistence of antibodies beyond 6 months after COVID-19. Therefore, as compared with immunocompetent patients, liver transplant recipients show a lower prevalence of anti-SARS-CoV-2 antibodies and more pronounced antibody levels decline.     

An early experience on the effect of solid organ transplant status on hospitalized COVID-19 patients

We compared the outcome of COVID-19 in immunosuppressed solid organ transplant (SOT) patients to a transplant naïve population. In total, 10 356 adult hospital admissions for COVID-19 from March 1, 2020 to April 27, 2020 were analyzed. Data were collected on demographics, baseline clinical conditions, medications, immunosuppression, and COVID-19 course. Primary outcome was combined death or mechanical ventilation. We assessed the association between primary outcome and prognostic variables using bivariate and multivariate regression models. We also compared the primary endpoint in SOT patients to an age, gender, and comorbidity-matched control group. Bivariate analysis found transplant status, age, gender, race/ethnicity, body mass index, diabetes, hypertension, cardiovascular disease, COPD, and GFR <60 mL/min/1.73 m² to be significant predictors of combined death or mechanical ventilation. After multivariate logistic regression analysis, SOT status had a trend toward significance (odds ratio [OR] 1.29; 95% CI 0.99–1.69, p = .06). Compared to an age, gender, and comorbidity-matched control group, SOT patients had a higher combined risk of death or mechanical ventilation (OR 1.34; 95% CI 1.03–1.74, p = .027).     

Mortality among solid organ waitlist candidates during COVID-19 in the United States

We examined the effects of COVID-19 on solid organ waiting list mortality in the United States and compared effects across patient demographics (e.g., race, age, and sex) and donation service areas. Three separate piecewise exponential survival models estimated for each solid organ the overall, demographic-specific, and donation service area-specific differences in the hazard of waitlist mortality before and after the national emergency declaration on March 13, 2020. Kidney waiting list mortality was higher after than before the national emergency (adjusted hazard ratio [aHR], 1.37; 95% CI, 1.23–1.52). The hazard of waitlist mortality was not significantly different before and after COVID-19 for liver (aHR, 0.94), pancreas (aHR, 1.01), lung (aHR, 1.00), and heart (aHR, 0.94). Kidney candidates had notable variability in differences across donation service areas (aHRs, New York City, 2.52; New Jersey, 1.84; and Michigan, 1.56). The only demographic group with increased waiting list mortality were Blacks versus Whites (aHR, 1.41; 95% CI, 1.07–1.86) for kidney candidates. The first 10 weeks after the declaration of a national emergency had a heterogeneous effect on waitlist mortality rate, varying by geography and ethnicity. This heterogeneity will complicate comparisons of transplant program performance during COVID-19.     

Liver transplantation performed in a SARS-CoV-2 positive hospitalized recipient using a SARS-CoV-2 infected donor

The coronavirus disease 2019 (COVID-19) is a novel infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). COVID-19 currently affected more than 108 million people worldwide with a fatality rate of 2.2%. Herein, we report the first case of liver transplantation (LT) performed with a liver procured from a SARS-CoV-2 positive donor. The recipient was a 35-year-old SARS-CoV-2 positive female patient affected by severe end-stage HBV-HDV-related liver disease (model of end-stage liver disease = 32) who had neutralizing SARS-CoV-2 antibodies (titers 1:320) at time of LT. The LT was successful, and the graft is functioning two months after surgery. The recipient cleared the SARS-CoV-2 infection 1 month after LT. The current case shows that the prompt use of SARS-CoV-2 infected liver donors offers an invaluable life-saving opportunity for SARS-CoV-2 positive wait-listed patients who developed neutralizing SARS-CoV-2 antibodies.     

COVID-19 in solid organ transplant recipients: a single-center experience

Solid organ transplant (SOT) recipients may be at risk for severe COVID-19. Data on the clinical course of COVID-19 in immunosuppressed patients are limited, and the effective treatment strategy for these patients is unknown. We describe our institutional experience with COVID-19 in SOT. Demographic, clinical, and treatment data were extracted from the electronic patient files. A total of 23 SOT transplant recipients suffering from COVID-19 were identified (n = 3 heart; n = 15 kidney; n = 1 kidney-after-heart; n = 3 lung, and n = 1 liver transplant recipient). The presenting symptoms were similar to nonimmunocompromised patients. Eighty-three percent (19/23) of the patients required hospitalization, but only two of these were transferred to the intensive care unit. Five patients died from COVID-19; all had high Clinical Frailty Scores. In four of these patients, mechanical ventilation was deemed futile. In 57% of patients, the immunosuppressive therapy was not changed and only three patients were treated with chloroquine. Most patients recovered without experimental antiviral therapy. Modification of the immunosuppressive regimen alone could be a therapeutic option for SOT recipients suffering from moderate to severe COVID-19. Pre-existent frailty is associated with death from COVID-19.     

Evolving Impact of COVID-19 on Transplant Center Practices and Policies in the United States

In our first survey of transplant centers in March 2020, >75% of kidney and liver programs were either suspended or operating under restrictions. To safely resume transplantation, we must understand the evolving impact of COVID-19 on transplant recipients and center-level practices. We therefore conducted a six-week follow-up survey May 7-15, 2020, and linked responses to the COVID-19 incidence map, with a response rate of 84%. Suspension of live donor transplantation decreased from 72% in March to 30% in May for kidneys and from 68% to 52% for livers. Restrictions/suspension of deceased donor transplantation decreased from 84% to 58% for kidneys and from 73% to 42% for livers. Resuming transplantation at normal capacity was envisioned by 83% of programs by August 2020. Exclusively using local recovery teams for deceased donor procurement was reported by 28%. Respondents reported caring for a total of 1166 COVID-19–positive transplant recipients; 25% were critically ill. Telemedicine challenges were reported by 81%. There was a lack of consensus regarding management of potential living donors or candidates with SARS-CoV-2. Our findings demonstrate persistent heterogeneity in center-level response to COVID-19 even as transplant activity resumes, making ongoing national data collection and real-time analysis critical to inform best practices.     

Liver transplantation for hepatitis C virus (HCV) non‐viremic recipients with HCV viremic donors

In the context of organ shortage, the opioid epidemic, and effective direct‐acting antiviral (DAA) therapy for hepatitis C virus (HCV), more HCV‐infected donor organs may be used for liver transplantation. Current data regarding outcomes after donor‐derived HCV in previously non‐viremic liver transplant recipients are limited. Clinical data for adult liver transplant recipients with donor‐derived HCV infection from March 2017 to January 2018 at our institution were extracted from the medical record. Ten patients received livers from donors known to be infected with HCV based on positive nucleic acid testing. Seven had a prior diagnosis of HCV and were treated before liver transplantation. All recipients were non‐viremic at the time of transplantation. All 10 recipients derived hepatitis C infection from their donor and achieved sustained virologic response at 12 weeks posttreatment with DAA‐based regimens, with a median time from transplant to treatment initiation of 43 days (IQR 20–59). There have been no instances of graft loss or death, with median follow‐up of 380 days (IQR 263–434) posttransplant. Transplantation of HCV‐viremic livers into non‐viremic recipients results in acceptable short‐term outcomes. Such strategies may be used to expand the donor pool and increase access to liver transplantation.     

Pediatric transplantation in Europe during the COVID-19 pandemic: Early impact on activity and healthcare

The current pandemic SARS-CoV-2 has required an unusual allocation of resources that can negatively impact chronically ill patients and high-complexity procedures. Across the European Reference Network on Pediatric Transplantation (ERN TransplantChild), we conducted a survey to investigate the impact of the COVID-19 outbreak on pediatric transplant activity and healthcare practices in both solid organ transplantation (SOT) and hematopoietic stem cell transplantation (HSCT). The replies of 30 professionals from 18 centers in Europe were collected. Twelve of 18 centers (67%) showed a reduction in their usual transplant activity. Additionally, outpatient visits have been modified and restricted to selected ones, and the use of telemedicine tools has increased. Additionally, a total of 14 COVID-19 pediatric transplanted patients were identified at the time of the survey, including eight transplant recipients and six candidates for transplantation. Only two moderate-severe cases were reported, both in HSCT setting. These survey results demonstrate the limitations in healthcare resources for pediatric transplantation patients during early stages of this pandemic. COVID-19 disease is a major worldwide challenge for the field of pediatric transplantation, where there will be a need for systematic data collection, encouraging regular discussions to address the long-term consequences for pediatric transplantation candidates, recipients, and their families.     

Prevalence and predictors of SARS-CoV-2 antibodies among solid organ transplant recipients with confirmed infection

It remains uncertain whether immunocompromised patients including solid organ transplant (SOT) recipients will have a robust antibody response to SARS-CoV-2 infection. We enrolled all adult SOT recipients at our center with confirmed SARS-CoV-2 infection who underwent antibody testing with a single commercially available anti-nucleocapsid antibody test at least 7 days after diagnosis in a retrospective cohort. Seventy SOT recipients were studied (56% kidney, 19% lung, 14% liver ± kidney, and 11% heart ± kidney recipients). Thirty-six (51%) had positive anti-nucleocapsid antibody testing, and 34 (49%) were negative. Recipients of a kidney allograft were less likely to have positive antibody testing compared to those who did not receive a kidney (p = .04). In the final multivariable model, the years from transplant to diagnosis (OR 1.26, p = .002) and baseline immunosuppression with more than two agents (OR 0.26, p = .03) were significantly associated with the antibody test result, controlling for kidney transplantation. In conclusion, among SOT recipients with confirmed infection, only 51% of patients had detectable anti-nucleocapsid antibodies, and transplant-related variables including the level and nature of immunosuppression were important predictors. These findings raise the concern that SOT recipients with COVID-19 may be less likely to form SARS-CoV-2 antibodies.     

COVID-19 in transplant recipients: The Spanish experience

We report the nationwide experience with solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients diagnosed with coronavirus disease 2019 (COVID-19) in Spain until 13 July 2020. We compiled information for 778 (423 kidney, 113 HSCT, 110 liver, 69 heart, 54 lung, 8 pancreas, 1 multivisceral) recipients. Median age at diagnosis was 61 years (interquartile range [IQR]: 52-70), and 66% were male. The incidence of COVID-19 in SOT recipients was two-fold higher compared to the Spanish general population. The median interval from transplantation was 59 months (IQR: 18-131). Infection was hospital-acquired in 13% of cases. No donor-derived COVID-19 was suspected. Most patients (89%) were admitted to the hospital. Therapies included hydroxychloroquine (84%), azithromycin (53%), protease inhibitors (37%), and interferon-β (5%), whereas immunomodulation was based on corticosteroids (41%) and tocilizumab (21%). Adjustment of immunosuppression was performed in 85% of patients. At the time of analysis, complete follow-up was available from 652 patients. Acute respiratory distress syndrome occurred in 35% of patients. Ultimately, 174 (27%) patients died. In univariate analysis, risk factors for death were lung transplantation (odds ratio [OR]: 2.5; 95% CI: 1.4-4.6), age >60 years (OR: 3.7; 95% CI: 2.5-5.5), and hospital-acquired COVID-19 (OR: 3.0; 95% CI: 1.9-4.9).     

Navigating the COVID-19 pandemic: Initial impacts and responses of the Organ Procurement and Transplantation Network in the United States

COVID-19 has been sweeping the globe, hitting the United States particularly hard with a state of emergency declared on March 13, 2020. Transplant hospitals have taken various precautions to protect patients from potential exposure. OPTN donor, candidate, and transplant data were analyzed from January 5, 2020 to September 5, 2020. The number of new waiting list registrations decreased, with the Northeast seeing over a 50% decrease from the week of 3/8 versus the week of 4/5. The national transplant system saw near cessation of living donor transplantation (−90%) from the week of 3/8 to the week of 4/5. Similarly, deceased donor kidney transplant volume dropped from 367 to 202 (−45%), and other organs saw similar decreases: lung (−70%), heart (−43%), and liver (−37%). Deceased donors recovered dropped from 260 to 163 (−45%) from 3/8 compared to 4/5, including a 67% decrease for lungs recovered. The magnitude of this decrease varied by geographic area, with the largest percent change (−67%) in the Northeast. Despite the pandemic, discard rates across organ has remained stable. Although the COVID-19 pandemic continues to evolve, OPTN data show recent evidence of stabilization, an indication that an early recovery of the number of living and deceased donors and transplants has ensued.     

Impact of Adult Living Donor Liver Transplantation on Waiting Time Survival in Candidates Listed for Liver Transplantation

Studies comparing adult living donor liver transplantation to deceased donor liver transplantation have focused on post-transplant survival. Our aim was to focus on the impact of living donor liver transplant on waiting time mortality and overall mortality. We analyzed the affect of living donor liver transplantation on waiting time mortality and overall mortality (from listing until last follow up) in a cohort of 116 transplant candidates. Fifty-eight candidates who had individuals present as potential living donors (volunteer group) were matched by MELD score to 58 liver transplant candidates who did not have individuals present as a potential living donor (no volunteer group). Twenty-seven percent of candidates in the no volunteer group and 62% of candidates in the volunteer group underwent liver transplantation, p = 0.0003. One-year waiting list mortality for the volunteer group and no volunteer group was 10% and 20%, respectively, p = 0.03. Patient survival from the time of listing to last follow up was similar between the two groups. In our study group, living donor liver transplantation is associated with a higher rate of liver transplantation and lower waiting time mortality. In the era of living donor liver transplantation, estimates of patient survival should incorporate waiting time mortality.     

Liver transplantation in the United States during the COVID-19 pandemic: National and center-level responses

COVID-19 has profoundly affected the American health care system; its effect on the liver transplant (LT) waitlist based on COVID-19 incidence has not been characterized. Using SRTR data, we compared observed LT waitlist registrations, waitlist mortality, deceased donor LTs (DDLT), and living donor LTs (LDLT) 3/15/2020-8/31/2020 to expected values based on historical trends 1/2016-1/2020, stratified by statewide COVID-19 incidence. Overall, from 3/15 to 4/30, new listings were 11% fewer than expected (IRR = _0.84 0.89_0.93), LDLTs were 49% fewer (IRR = _0.37 0.51_0.72), and DDLTs were 9% fewer (IRR = _0.85 0.91_0.97). In May, new listings were 21% fewer (IRR = _0.74 0.79_0.84), LDLTs were 42% fewer (IRR = _0.39 0.58_0.85) and DDLTs were 13% more (IRR = _1.07 1.15_1.23). Centers in states with the highest incidence 3/15-4/30 had 59% more waitlist deaths (IRR = _1.09 1.59_2.32) and 34% fewer DDLTs (IRR = _0.50 0.66_0.86). By August, waitlist outcomes were occurring at expected rates, except for DDLT (13% more across all incidences). While the early COVID-affected states endured major transplant practice changes, later in the pandemic the newly COVID-affected areas were not impacted to the same extent. These results speak to the adaptability of the transplant community in addressing the pandemic and applying new knowledge to patient care.     

Evaluation of clinical outcomes of prophylactic versus preemptive cytomegalovirus strategy in liver transplant recipients

Cytomegalovirus (CMV) is a major cause of morbidity and mortality following solid organ transplantation (SOT). Two strategies, prophylactic, and preemptive have emerged for the prevention of CMV infection and disease after SOT. This retrospective chart review of two liver transplant cohorts: prophylactic and preemptive, compares the clinical impact of transitioning from prophylactic to preemptive strategy. The primary outcome is the incidence of CMV viremia at 3‐and 6‐months post‐transplant. Secondary outcomes include: incidence of CMV tissue‐invasive disease, acute cellular rejection, leukopenia and neutropenia, opportunistic infection rates, hospital readmission rates, and mortality at 3‐and 6‐months post‐transplant. A total of 109 patients were included in the analysis. The incidence of CMV viremia was 4.9% and 50.0% (P < 0.001) in the prophylactic versus preemptive cohort, respectively, at 3 months post‐transplant. The incidence of CMV viremia was 24.6% and 8.3% (P = 0.026) in the prophylactic versus preemptive cohort, respectively, at 6 months post‐transplant. There were no statistical significant differences in the secondary outcomes between both cohorts. In conclusion, there is a statistical significant difference in time to onset of CMV viremia; however, the use of either prophylactic or preemptive strategy was not associated with significant negative clinical outcomes of CMV.