Excess mortality among kidney transplant recipients: Impact of COVID-19-related deaths during the pandemic.

BACKGROUND: Because COVID-19 has been associated with high lethality rates among kidney transplant recipients (KTR), but also with a severe disruption and delays in overall healthcare, this study aims to evaluate the excess mortality in the pandemic era among KTR in a high-volume Brazilian transplant center. METHODS: This study used data from a single center that provides follow-up on all its transplant recipients. The population of interest included all the patients who were transplanted between August 31, 1983 and December 31, 2022 and who were live from January 1, 2014. Using the "AutoRegressive Integrated Moving Average" forecasting algorithm, the expected mortality for the pandemic era (2020-2022) was modeled from the pre-pandemic era (2014-2019). RESULTS: There were 12 077 KTRs at risk of dying in the entire observation period. In the pre-pandemic era, there were 21 deaths per 1000 patients at risk. In the pandemic era, there were 1429 observed deaths (rate of 47 deaths per 1000 patients at risk) versus the expected 587 deaths, resulting in an absolute number of 842 excess deaths, or an observed-to-expected ratio of 2.4, or an absolute rate of 26 deaths in excess per 1000 patients at risk. The excess deaths exhibited a temporal pattern mirroring that of the surges in new cases and lethality rates of COVID-19. COVID-19-related deaths drove 94% of excess mortality in the pandemic era. CONCLUSION: In this large cohort of KTR under centralized follow-up, more than twofold excess mortality was primarily driven by COVID-19-related deaths, highlighting the vulnerability of this population to the most severe presentation of SARS-CoV-2 infection.

The impact of universal induction therapy on early hospital readmission of kidney transplant recipients / O impacto da terapia de indução universal na readmissão hospitalar precoce de receptores de transplante renal

ABSTRACT Background: Early hospital readmission (EHR) is associated with worse outcomes. The use of anti-thymocyte globulin (rATG) induction therapy is associated with increased efficacy in preventing acute rejection, although safety concerns still exist. Methods: This retrospective single-center study compared the incidence, causes of EHR, and one-year clinical outcomes of patients receiving a kidney transplant between August 18, 2011 and December 31, 2012 (old era), in which only high-risk patients received 5 mg/kg rATG, with those transplanted between August 18, 2014 and December 31, 2015 (new era), in which all patients received a single 3 mg/kg dose of rATG. Results: There were 788 patients from the Old Era and 800 from the New Era. The EHR incidence in the old era patients was 26.4% and in the new era patients, 22.5% (p = 0.071). The main cause of EHR in both eras was infection (67% vs. 68%). The incidence of acute rejection episodes was lower (22.7% vs 3.5%, p < 0.001) and the one-year patient survival was higher (95.6% vs. 98.1%, vs. p = 0.004) in new era patients. Conclusion: The universal use of 3 mg/kg rATG single-dose induction therapy in the new era was associated with a trend towards reduced EHR and a reduction in the incidence of acute rejection and mortality.

Resumo Histórico: A Readmissão Hospitalar Precoce (RHP) está associada a piores desfechos. O uso de terapia de indução com globulina antitimócito (rATG, por sua sigla em inglês) está associado ao aumento da eficácia na prevenção de rejeição aguda, embora ainda existam preocupações quanto à segurança. Métodos: Este estudo retrospectivo de centro único comparou a incidência, as causas da RHP e os desfechos clínicos de um ano de pacientes que receberam transplante renal entre 18 de Agosto de 2011 e 31 de Dezembro de 2012 (Antiga Era), em que apenas pacientes de alto risco receberam 5 mg/kg de rATG, com aqueles transplantados entre 18 de Agosto de 2014 e 31 de Dezembro de 2015 (Nova Era), em que todos os pacientes receberam uma única dose de 3 mg/kg de rATG. Resultados: Houve 788 pacientes da Antiga Era e 800 da Nova Era. A incidência de RHP nos pacientes da antiga era foi de 26,4% e nos pacientes da nova era, 22,5% (p = 0,071). A principal causa de RHP em ambas as eras foi infecção (67% vs. 68%). A incidência de episódios de rejeição aguda foi menor (22,7% vs. 3,5%; p < 0,001) e a sobrevida do paciente em um ano foi maior (95,6% vs. 98,1%; vs. p = 0,004) em pacientes da nova era. Conclusão: O uso universal de terapia de indução de 3 mg/kg de rATG em dose única na nova era foi associado a uma tendência à redução da RHP e a uma redução na incidência de rejeição aguda e mortalidade.

The impact of universal induction therapy on early hospital readmission of kidney transplant recipients.

BACKGROUND: Early hospital readmission (EHR) is associated with worse outcomes. The use of anti-thymocyte globulin (rATG) induction therapy is associated with increased efficacy in preventing acute rejection, although safety concerns still exist. METHODS: This retrospective single-center study compared the incidence, causes of EHR, and one-year clinical outcomes of patients receiving a kidney transplant between August 18, 2011 and December 31, 2012 (old era), in which only high-risk patients received 5 mg/kg rATG, with those transplanted between August 18, 2014 and December 31, 2015 (new era), in which all patients received a single 3 mg/kg dose of rATG. RESULTS: There were 788 patients from the Old Era and 800 from the New Era. The EHR incidence in the old era patients was 26.4% and in the new era patients, 22.5% (p = 0.071). The main cause of EHR in both eras was infection (67% vs. 68%). The incidence of acute rejection episodes was lower (22.7% vs 3.5%, p < 0.001) and the one-year patient survival was higher (95.6% vs. 98.1%, vs. p = 0.004) in new era patients. CONCLUSION: The universal use of 3 mg/kg rATG single-dose induction therapy in the new era was associated with a trend towards reduced EHR and a reduction in the incidence of acute rejection and mortality.

Risk factors of transplant renal artery stenosis in kidney transplant recipients.

BACKGROUND: Transplant Renal Artery Stenosis (TRAS) is a recognized vascular complication after kidney transplantation. The overall risk predictors of TRAS are poorly understood. METHODS: Retrospective analysis of patients with suspected TRAS (Doppler ultrasound PSV > 200 cm/s) who underwent angiographic study in a single center between 2007 and 2014. All patients with stenosis > 50% were considered with TRAS. Stenosis restricted in the body of the artery was also analyzed in a subgroup. RESULTS: 274 patients were submitted to a renal angiography and 166 confirmed TRAS. TRAS group featured an older population (46.3 ± 11.0 vs. 40.9 ±14.2 years; p = 0.001), more frequent hypertensive nephropathy (30.1% vs. 15.7%; p = 0.01), higher incidence of Delayed Graft Function (DGF) (52.0% vs. 25.6%; p < 0.001) and longer Cold Ischemia Time (CIT) (21.5 ± 10.6 vs. 15.7 ± 12.9h; p < 0.001). In multivariable analyses, DGF (OR = 3.31; 95% CI 1.78‒6.30; p < 0.0001) was independent risk factors for TRAS. DM and CIT showed a tendency towards TRAS. The compound discriminatory capacity of the multivariable model (AUC = 0.775; 95% CI 0.718‒0.831) is significantly higher than systolic blood pressure and creatinine alone (AUC = 0.62; 95% CI 0.558-0.661). In body artery stenosis subgroup, DGF (OR = 1.86; 95% CI 1.04‒3.36; p = 0.03) and Diabetes Mellitus (DM) (OR = 2.44; 95% CI 1.31‒4.60; p = 0.005) were independent risk factors for TRAS. CONCLUSION: In our transplant population, DGF increased more than 3-fold the risk of TRAS. In the subgroup analysis, both DGF and DM increases the risk of body artery stenosis. The addition of other factors to hypertension and renal dysfunction may increase diagnostic accuracy. TRAS TRIAL REGISTRED: clinicaltrials.gov (n° NCT04225338).

Transition from antigenemia to quantitative nucleic acid amplification testing in cytomegalovirus-seropositive kidney transplant recipients receiving preemptive therapy for cytomegalovirus infection.

Due to the high costs, the strategy to reduce the impact of cytomegalovirus (CMV) after kidney transplant (KT) involves preemptive treatment in low and middle-income countries. Thus, this retrospective cohort study compared the performance of antigenemia transitioned to quantitative nucleic acid amplification testing, RT-PCR, in CMV-seropositive KT recipients receiving preemptive treatment as a strategy to prevent CMV infection. Between 2016 and 2018, 363 patients were enrolled and received preemptive treatment based on antigenemia (n = 177) or RT-PCR (n = 186). The primary outcome was CMV disease. Secondarily, the CMV-related events were composed of CMV-infection and disease, which occurred first. There were no differences in 1-year cumulative incidence of CMV-disease (23.7% vs. 19.1%, p = 0.41), CMV-related events (50.8% vs. 44.1%, p = 0.20), neither in time to diagnosis (47.0 vs. 47.0 days) among patients conducted by antigenemia vs. RT-PCR, respectively. The length of CMV first treatment was longer with RT-PCR (20.0 vs. 27.5 days, p < 0.001), while the rate of retreatment was not different (14.7% vs. 11.8%, p = 0.48). In the Cox regression, acute rejection within 30 days was associated with an increased the risk (HR = 2.34; 95% CI = 1.12-4.89; p = 0.024), while each increase of 1 mL/min/1.73 m2 of 30-day eGFR was associated with a 2% reduction risk of CMV-disease (HR = 0.98; 95% CI = 0.97-0.99; p = 0.001). In conclusion, acute rejection and glomerular filtration rate are risk factors for CMV disease, showing comparable performance in the impact of CMV-related events between antigenemia and RT-PCR for preemptive treatment.

Risk factors of transplant renal artery stenosis in kidney transplant recipients

Abstract Background: Transplant Renal Artery Stenosis (TRAS) is a recognized vascular complication after kidney transplantation. The overall risk predictors of TRAS are poorly understood. Methods: Retrospective analysis of patients with suspected TRAS (Doppler ultrasound PSV > 200 cm/s) who underwent angiographic study in a single center between 2007 and 2014. All patients with stenosis > 50% were considered with TRAS. Stenosis restricted in the body of the artery was also analyzed in a subgroup. Results: 274 patients were submitted to a renal angiography and 166 confirmed TRAS. TRAS group featured an older population (46.3 ± 11.0 vs. 40.9 ±14.2 years; p = 0.001), more frequent hypertensive nephropathy (30.1% vs. 15.7%; p = 0.01), higher incidence of Delayed Graft Function (DGF) (52.0% vs. 25.6%; p < 0.001) and longer Cold Ischemia Time (CIT) (21.5 ± 10.6 vs. 15.7 ± 12.9h; p < 0.001). In multivariable analyses, DGF (OR = 3.31; 95% CI 1.78-6.30; p < 0.0001) was independent risk factors for TRAS. DM and CIT showed a tendency towards TRAS. The compound discriminatory capacity of the multivariable model (AUC = 0.775; 95% CI 0.718-0.831) is significantly higher than systolic blood pressure and creatinine alone (AUC = 0.62; 95% CI 0.558-0.661). In body artery stenosis subgroup, DGF (OR = 1.86; 95% CI 1.04-3.36; p = 0.03) and Diabetes Mellitus (DM) (OR = 2.44; 95% CI 1.31-4.60; p = 0.005) were independent risk factors for TRAS. Conclusion: In our transplant population, DGF increased more than 3-fold the risk of TRAS. In the subgroup analysis, both DGF and DM increases the risk of body artery stenosis. The addition of other factors to hypertension and renal dysfunction may increase diagnostic accuracy.

The influence of the antithymocyte globulin dose on clinical outcomes of patients undergoing kidney retransplantation.

Optimizing antithymocyte globulin (rATG) dosage is critical for high immunological risk patients undergoing a repeat kidney transplant. This natural retrospective cohort study compared clinical outcomes of two successive cohorts of consecutive recipients of retransplants receiving 5 x 1 mg/kg (rATG-5, n = 100) or a single 3 mg/kg (rATG-3, n = 110) dose of rATG induction therapy. All patients had negative complement-dependent cytotoxicity crossmatch and no anti-HLA A, B, DR donor-specific antibodies (DSA). The primary endpoint was efficacy failure (first biopsy-proven acute rejection, graft loss, or death) at 12 months. There was no difference in the cumulative incidence of efficacy failure (18.0% vs. 21.8%, HR = 1.22, 95% CI 0.66-2.25), respectively. There were no differences in 3-years freedom from biopsy proven acute rejection, and patient, graft, and death-censored graft survivals. There were no differences in the incidence of surgical complications (25.0% vs. 18.2%; p 0.151), early hospital readmission (27.8% vs. 29.5%; p = 0.877) and CMV infections (49% vs. 40%; p = 0.190). There were also no differences in the incidence (59.6% vs. 58.7%, p = 0.897) and duration of delayed graft function but a stable difference in estimate glomerular filtration rate was observed from month 1 (54.7±28.8 vs. 44.1±25.3 ml/min/1.73 m2, p = 0.005) to month 36 (51.1±27.7 vs. 42.5±24.5, p = 0.019). Mean urinary protein concentration (month 36: 0.38±0.81 vs. 0.70±2.40 g/ml, p = 0.008) and mean chronic glomerular Banff score in for cause biopsies (months 4-36: 0.0±0.0 vs. 0.04±0.26, p = 0.044) were higher in the rATG-3 group. This cohort analysis did not detect differences in the incidence of efficacy failure and in safety outcomes at 12 months among recipients of kidney retransplants without A, B, and DR DSA, receiving induction therapy with a single 3 mg/kg rATG dose or the traditional 5 mg/kg rATG.

The Full Spectrum of COVID-19 Development and Recovery Among Kidney Transplant Recipients.

BACKGROUND: Coronavirus disease 2019 (COVID-19) fatality rate is high among kidney transplant recipients. Among survivors, kidney outcomes, seroconversion, and persistence of viral shedding are unexplored. METHODS: Single-center prospective cohort study including data from kidney transplant recipients with confirmed COVID-19 between March 20, 2020 and July 31, 2020. Outcomes were adjudicated until August 31, 2020 or the date of death. RESULTS: There were 491 patients with COVID-19 among the 11 875 recipients in follow-up. The majority were middle aged with ≥1 comorbidities. Thirty-one percent were treated at home, and 69% required hospitalization. Among the hospitalized, 61% needed intensive care, 75% presented allograft dysfunction, and 46% needed dialysis. The overall 28-day fatality rate was 22% and among hospitalized patients it was 41%. Age (odds ratio, 3.08; 95% confidence interval, 1.86-5.09), diabetes mellitus (odds ratio, 1.69; 95% confidence interval, 1.06-2.72), and cardiac disease (odds ratio, 2.00; 95% confidence interval, 1.09-3.68) were independent factors for death. Among the 351 survivors, 19% sustained renal graft dysfunction, and there were 13 (4%) graft losses. Biopsy (n = 20) findings were diverse but decisive to guide treatment and estimate prognosis. Seroconversion was observed in 79% of the survivors and was associated with disease severity. Persistence of viral shedding was observed in 21% of the patients without detectable clinical implications. CONCLUSIONS: This prospective cohort analysis confirms the high 28-day fatality rate of COVID-19, associated primarily with age and comorbidities. The high incidence of allograft dysfunction was associated with a wide range of specific histologic lesions and high rates of sequelae and graft loss. Seroconversion was high and the persistence of viral shedding deserves further studies.

Is There Sufficient Evidence Justifying Limited Access of Jehovah's Witness Patients to Kidney Transplantation?

BACKGROUND: Jehovah's Witnesses (JWs) refuse blood transfusions due to religious issues. This situation may impact kidney transplantation (KT) outcomes in case of hemorrhagic complications. We evaluated demographic characteristics of this population, hematologic safety, and graft outcomes. METHODS: This was a retrospective, single-center study comparing KT outcomes in JW patients versus a non-JW control group. Hematologic endpoints included clinical indication for blood transfusion (hemoglobin <7 g/dL), decrease of hemoglobin >2 g/dL or hematocrit >5% in the first week after KT, hemorrhagic complications requiring surgery, and de novo prescription of erythropoiesis-stimulating agents. Secondary endpoints included delayed graft function, treated biopsy-proven acute rejection, renal function, mortality, and graft survival at 12 months. RESULTS: From January 1989 to September 2018, we identified 143 JW (10 pediatric) and selected 142 matched control (non-JW) patients. There were no differences in the incidence of clinical indication for transfusion (13.3% versus 11.3%, P = 0.640), but a higher proportion of non-JW patients received transfusions (2.1% versus 9.2%, P = 0.010). There were no differences in the proportion of patients with decreased hemoglobin concentration, in reinterventions due to hemorrhagic complications, in the use of erythropoiesis-stimulating agents at hospital discharge, in the incidence of acute rejection, in renal function, and in mortality or graft survival rate at 12 months. CONCLUSIONS: In summary, this matched control cohort study suggests that, when clinically indicated, blood transfusions can be safely avoided in the majority of JW kidney transplant, who achieve and maintain comparable hemoglobin concentrations during the first year after transplantation compared with non-JW patients.