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1.
Cell ; 185(6): 1008-1024.e15, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35202565

RESUMO

Vaccine-mediated immunity often relies on the generation of protective antibodies and memory B cells, which commonly stem from germinal center (GC) reactions. An in-depth comparison of the GC responses elicited by SARS-CoV-2 mRNA vaccines in healthy and immunocompromised individuals has not yet been performed due to the challenge of directly probing human lymph nodes. Herein, through a fine-needle aspiration-based approach, we profiled the immune responses to SARS-CoV-2 mRNA vaccines in lymph nodes of healthy individuals and kidney transplant recipients (KTXs). We found that, unlike healthy subjects, KTXs presented deeply blunted SARS-CoV-2-specific GC B cell responses coupled with severely hindered T follicular helper cell, SARS-CoV-2 receptor binding domain-specific memory B cell, and neutralizing antibody responses. KTXs also displayed reduced SARS-CoV-2-specific CD4 and CD8 T cell frequencies. Broadly, these data indicate impaired GC-derived immunity in immunocompromised individuals and suggest a GC origin for certain humoral and memory B cell responses following mRNA vaccination.

2.
Am J Kidney Dis ; 81(2): 222-231.e1, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36191727

RESUMO

RATIONALE & OBJECTIVE: Donor acute kidney injury (AKI) activates innate immunity, enhances HLA expression in the kidney allograft, and provokes recipient alloimmune responses. We hypothesized that injury and inflammation that manifested in deceased-donor urine biomarkers would be associated with higher rates of biopsy-proven acute rejection (BPAR) and allograft failure after transplantation. STUDY DESIGN: Prospective cohort. SETTING & PARTICIPANTS: 862 deceased donors for 1,137 kidney recipients at 13 centers. EXPOSURES: We measured concentrations of interleukin 18 (IL-18), kidney injury molecule 1 (KIM-1), and neutrophil gelatinase-associated lipocalin (NGAL) in deceased donor urine. We also used the Acute Kidney Injury Network (AKIN) criteria to assess donor clinical AKI. OUTCOMES: The primary outcome was a composite of BPAR and graft failure (not from death). A secondary outcome was the composite of BPAR, graft failure, and/or de novo donor-specific antibody (DSA). Outcomes were ascertained in the first posttransplant year. ANALYTICAL APPROACH: Multivariable Fine-Gray models with death as a competing risk. RESULTS: Mean recipient age was 54 ± 13 (SD) years, and 82% received antithymocyte globulin. We found no significant associations between donor urinary IL-18, KIM-1, and NGAL and the primary outcome (subdistribution hazard ratio [HR] for highest vs lowest tertile of 0.76 [95% CI, 0.45-1.28], 1.20 [95% CI, 0.69-2.07], and 1.14 [95% CI, 0.71-1.84], respectively). In secondary analyses, we detected no significant associations between clinically defined AKI and the primary outcome or between donor biomarkers and the composite outcome of BPAR, graft failure, and/or de novo DSA. LIMITATIONS: BPAR was ascertained through for-cause biopsies, not surveillance biopsies. CONCLUSIONS: In a large cohort of kidney recipients who almost all received induction with thymoglobulin, donor injury biomarkers were associated with neither graft failure and rejection nor a secondary outcome that included de novo DSA. These findings provide some reassurance that centers can successfully manage immunological complications using deceased-donor kidneys with AKI.


Assuntos
Injúria Renal Aguda , Transplante de Rim , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Lipocalina-2 , Interleucina-18 , Estudos Prospectivos , Injúria Renal Aguda/patologia , Doadores de Tecidos , Biomarcadores , Rejeição de Enxerto/epidemiologia , Sobrevivência de Enxerto
3.
Am J Transplant ; 22(2): 599-609, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34613666

RESUMO

Kidney transplantation (KT) from deceased donors with hepatitis C virus (HCV) into HCV-negative recipients has become more common. However, the risk of complications such as BK polyomavirus (BKPyV) remains unknown. We assembled a retrospective cohort at four centers. We matched recipients of HCV-viremic kidneys to highly similar recipients of HCV-aviremic kidneys on established risk factors for BKPyV. To limit bias, matches were within the same center. The primary outcome was BKPyV viremia ≥1000 copies/ml or biopsy-proven BKPyV nephropathy; a secondary outcome was BKPyV viremia ≥10 000 copies/ml or nephropathy. Outcomes were analyzed using weighted and stratified Cox regression. The median days to peak BKPyV viremia level was 119 (IQR 87-182). HCV-viremic KT was not associated with increased risk of the primary BKPyV outcome (HR 1.26, p = .22), but was significantly associated with the secondary outcome of BKPyV ≥10 000 copies/ml (HR 1.69, p = .03). One-year eGFR was similar between the matched groups. Only one HCV-viremic kidney recipient had primary graft loss. In summary, HCV-viremic KT was not significantly associated with the primary outcome of BKPyV viremia, but the data suggested that donor HCV might elevate the risk of more severe BKPyV viremia ≥10 000 copies/ml. Nonetheless, one-year graft function for HCV-viremic recipients was reassuring.


Assuntos
Vírus BK , Transplante de Rim , Infecções por Polyomavirus , Infecções Tumorais por Vírus , Hepacivirus , Humanos , Transplante de Rim/efeitos adversos , Estudos Retrospectivos , Infecções Tumorais por Vírus/etiologia , Viremia
4.
Clin Infect Dis ; 73(11): e4090-e4099, 2021 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-32766815

RESUMO

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has led to significant reductions in transplantation, motivated in part by concerns of disproportionately more severe disease among solid organ transplant (SOT) recipients. However, clinical features, outcomes, and predictors of mortality in SOT recipients are not well described. METHODS: We performed a multicenter cohort study of SOT recipients with laboratory-confirmed COVID-19. Data were collected using standardized intake and 28-day follow-up electronic case report forms. Multivariable logistic regression was used to identify risk factors for the primary endpoint, 28-day mortality, among hospitalized patients. RESULTS: Four hundred eighty-two SOT recipients from >50 transplant centers were included: 318 (66%) kidney or kidney/pancreas, 73 (15.1%) liver, 57 (11.8%) heart, and 30 (6.2%) lung. Median age was 58 (interquartile range [IQR] 46-57), median time post-transplant was 5 years (IQR 2-10), 61% were male, and 92% had ≥1 underlying comorbidity. Among those hospitalized (376 [78%]), 117 (31%) required mechanical ventilation, and 77 (20.5%) died by 28 days after diagnosis. Specific underlying comorbidities (age >65 [adjusted odds ratio [aOR] 3.0, 95% confidence interval [CI] 1.7-5.5, P < .001], congestive heart failure [aOR 3.2, 95% CI 1.4-7.0, P = .004], chronic lung disease [aOR 2.5, 95% CI 1.2-5.2, P = .018], obesity [aOR 1.9, 95% CI 1.0-3.4, P = .039]) and presenting findings (lymphopenia [aOR 1.9, 95% CI 1.1-3.5, P = .033], abnormal chest imaging [aOR 2.9, 95% CI 1.1-7.5, P = .027]) were independently associated with mortality. Multiple measures of immunosuppression intensity were not associated with mortality. CONCLUSIONS: Mortality among SOT recipients hospitalized for COVID-19 was 20.5%. Age and underlying comorbidities rather than immunosuppression intensity-related measures were major drivers of mortality.


Assuntos
COVID-19 , Transplante de Órgãos , Estudos de Coortes , Humanos , Masculino , Pessoa de Meia-Idade , Transplante de Órgãos/efeitos adversos , SARS-CoV-2 , Transplantados
6.
Clin Transplant ; 32(4): e13215, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29393541

RESUMO

BACKGROUND: Kidney transplant (KT) recipients experience high rates of early (≤30 days) hospital readmission (EHR) after KT, and existing studies provide limited data on modifiable discharge factors that may mitigate EHR risk. METHODS: We performed a retrospective cohort study of 468 adult deceased donor KT recipients transplanted between 4/2010 and 11/2013 at 5 United States transplant centers. We fit multivariable mixed effects models to assess the association of two potentially modifiable discharge factors with the probability of EHR after KT: (i) weekend discharge and (ii) days to first scheduled follow-up. RESULTS: Among 468 KT recipients, 38% (n = 178) experienced EHR after KT. In fully adjusted analyses, compared to weekday discharges, KT recipients discharged on the weekend had a 29% lower risk of EHR (adjusted odds ratio [aOR] 0.71, 95% confidence interval [CI] 0.41-0.94). Compared to follow-up within 2 days of discharge, KT recipients with follow-up within 3 to 6 days had a 28% higher probability of EHR (aOR 1.28, 95% CI 1.13-1.45). CONCLUSIONS: These findings suggest that clinical decisions related to the timing of discharge and follow-up modify EHR risk after KT, independent of traditional risk factors.


Assuntos
Rejeição de Enxerto/prevenção & controle , Falência Renal Crônica/cirurgia , Transplante de Rim/métodos , Alta do Paciente/estatística & dados numéricos , Readmissão do Paciente/estatística & dados numéricos , Doadores de Tecidos/estatística & dados numéricos , Adulto , Cadáver , Estudos de Coortes , Feminino , Seguimentos , Taxa de Filtração Glomerular , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Testes de Função Renal , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco
8.
POCUS J ; 7(Kidney): 30-32, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36896118

RESUMO

A radiographic incidental finding (sometimes called an incidentaloma) is defined as a structure that is unintentionally found during an exam for an unrelated indication. The increased use of routine abdominal imaging is associated with a rising incidence in incidentalomas of the kidney 1. In one meta-analysis, 75% of renal incidentalomas were benign 2. However, the overall prevalence of incidental carcinomas is low at 0.2% 3. With the growing uptake of POCUS, healthy volunteers for clinical demonstrations may find themselves with new findings despite a lack of symptoms 4. Having an incidentaloma discovered during the course of a nephrology POCUS workshop is a unique experience. Herein we report our experiences of having incidentalomas discovered during the course of POCUS demonstrations.

9.
Transplant Direct ; 8(8): e1341, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35923812

RESUMO

Background: Historically, many organs from deceased donors with hepatitis C virus (HCV) were discarded. The advent of highly curative direct-acting antiviral (DAA) therapies motivated transplant centers to conduct trials of transplanting HCV-viremic organs (nucleic acid amplification test positive) into HCV-negative recipients, followed by DAA treatment. However, the factors that influence candidates' decisions regarding acceptance of transplant with HCV-viremic organs are not well understood. Methods: To explore patient-level perceptions, influences, and experiences that inform candidate decision-making regarding transplant with organs from HCV-viremic donors, we conducted a qualitative semistructured interview study embedded within 3 clinical trials investigating the safety and efficacy of transplanting lungs and kidneys from HCV-viremic donors into HCV-negative recipients. The study was conducted from June 2019 to March 2021. Results: Among 44 HCV-negative patients listed for organ transplant who were approached for enrollment in the applicable clinical trial, 3 approaches to decision-making emerged: positivist, risk analyses, and instinctual response. Perceptions of risk contributed to conceptualizations of factors influencing decisions. Moreover, most participants relied on multiple decision-making approaches, either simultaneously or sequentially. Conclusions: Understanding how different decisional models influence patients' choices regarding transplant with organs from HCV-viremic donors may promote shared decision-making among transplant patients and providers.

11.
medRxiv ; 2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34580676

RESUMO

Vaccine-mediated immunity often relies on the generation of protective antibodies and memory B cells, which commonly stem from germinal center (GC) reactions. An in-depth comparison of the GC responses elicited by SARS-CoV-2 mRNA vaccines in healthy and immunocompromised individuals has not yet been performed due to the challenge of directly probing human lymph nodes. In this study, through a fine-needle-aspiration-based approach, we profiled the immune responses to SARS-CoV-2 mRNA vaccines in lymph nodes of healthy individuals and kidney transplant (KTX) recipients. We found that, unlike healthy subjects, KTX recipients presented deeply blunted SARS-CoV-2-specific GC B cell responses coupled with severely hindered T follicular helper cells, SARS-CoV-2 receptor-binding-domain-specific memory B cells and neutralizing antibodies. KTX recipients also displayed reduced SARS-CoV-2-specific CD4 and CD8 T cell frequencies. Broadly, these data indicate impaired GC-derived immunity in immunocompromised individuals, and suggest a GC-origin for certain humoral and memory B cell responses following mRNA vaccination.

12.
Clin Teach ; 14(6): 412-416, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27860219

RESUMO

BACKGROUND: Engaging in scholarly activity during residency can facilitate the acquisition of important skills; however, residents may encounter barriers such as unclear expectations as to what constitutes scholarship, a paucity of dedicated time and a lack of mentorship. Residents may encounter barriers such as unclear expectations as to what constitutes scholarship OBJECTIVE: In July 2013, we developed a Case Report Curriculum (CRC) for first-year residents to guide them towards creating a high-quality case report and helping them to achieve the Accreditation Council for Graduate Medical Education scholarly activity requirement. METHODS: The CRC is composed of four 1-hour educational sessions (seminars and group work) at intervals of 4-6 weeks, with specific homework assignments. Sessions are divided into four topics: (1) importance of scholarship and selecting a case; (2) defining appropriate learning objectives; (3) writing a discussion; and (4) editing and submitting. The culmination of the CRC is a poster competition at our institutional Academic Week. RESULTS: In 2012/13, the year prior to CRC implementation, six of 18 (33%) first-year residents participated in scholarly activity. During the following 2 years, 20 of 20 (100%) of the 2013/14 first-year residents and 21 of 22 (95%) of the 2014/15 first-year residents participated in the CRC and presented a case report. Furthermore, 16 of 20 (80%) of the first-year residents who completed the CRC in 2013/14 voluntarily continued to work on scholarly projects, with a total of 44 projects published or presented regionally or nationally. DISCUSSION: The CRC represents a practical structured framework for promoting scholarship, which can be easily implemented in a residency programme.


Assuntos
Bolsas de Estudo , Internato e Residência/métodos , Currículo , Avaliação Educacional , Bolsas de Estudo/métodos , Humanos
14.
Can Urol Assoc J ; 5(4): E60-4, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21806896

RESUMO

We report a case of primary transitional cell carcinoma (TCC) of a bladder diverticum along with a literature review. A 55-year-old male presented with painless gross hematuria. A histological diagnosis of TCC within a bladder diverticulum was made following cystoscopical examination. Initially transurethral resection of bladder tumour with subsequent intravesical chemotherapy followed. As a result of recurrence and in view of bladder-sparing therapy, a distal partial cystectomy was performed. This report demonstrates that conservative bladder-sparing treatment can be achieved and subsequently followed by vigilant cystoscopy.

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