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1.
Am J Transplant ; 24(3): 362-379, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37871799

ABSTRACT

The Banff pancreas working schema for diagnosis and grading of rejection is widely used for treatment guidance and risk stratification in centers that perform pancreas allograft biopsies. Since the last update, various studies have provided additional insight regarding the application of the schema and enhanced our understanding of additional clinicopathologic entities. This update aims to clarify terminology and lesion description for T cell-mediated and antibody-mediated allograft rejections, in both active and chronic forms. In addition, morphologic and immunohistochemical tools are described to help distinguish rejection from nonrejection pathologies. For the first time, a clinicopathologic approach to islet pathology in the early and late posttransplant periods is discussed. This update also includes a discussion and recommendations on the utilization of endoscopic duodenal donor cuff biopsies as surrogates for pancreas biopsies in various clinical settings. Finally, an analysis and recommendations on the use of donor-derived cell-free DNA for monitoring pancreas graft recipients are provided. This multidisciplinary effort assesses the current role of pancreas allograft biopsies and offers practical guidelines that can be helpful to pancreas transplant practitioners as well as experienced pathologists and pathologists in training.


Subject(s)
Pancreas Transplantation , Transplantation, Homologous , Biopsy , Isoantibodies , T-Lymphocytes
4.
Transpl Int ; 36: 11589, 2023.
Article in English | MEDLINE | ID: mdl-37680647

ABSTRACT

The Thrombotic Microangiopathy Banff Working Group (TMA-BWG) was formed in 2015 to survey current practices and develop minimum diagnostic criteria (MDC) for renal transplant TMA (Tx-TMA). To generate consensus among pathologists and nephrologists, the TMA BWG designed a 3-Phase study. Phase I of the study is presented here. Using the Delphi methodology, 23 panelists with >3 years of diagnostic experience with Tx-TMA pathology listed their MDC suggesting light, immunofluorescence, and electron microscopy lesions, clinical and laboratory information, and differential diagnoses. Nine rounds (R) of consensus resulted in MDC validated during two Rs using online evaluation of whole slide digital images of 37 biopsies (28 TMA, 9 non-TMA). Starting with 338 criteria the process resulted in 24 criteria and 8 differential diagnoses including 18 pathologic, 2 clinical, and 4 laboratory criteria. Results show that 3/4 of the panelists agreed on the diagnosis of 3/4 of cases. The process also allowed definition refinement for 4 light and 4 electron microscopy lesions. For the first time in Banff classification, the Delphi methodology was used to generate consensus. The study shows that Delphi is a democratic and cost-effective method allowing rapid consensus generation among numerous physicians dealing with large number of criteria in transplantation.


Subject(s)
Kidney Transplantation , Thrombotic Microangiopathies , Humans , Consensus , Cost-Benefit Analysis , Biopsy
5.
Transpl Int ; 36: 11590, 2023.
Article in English | MEDLINE | ID: mdl-37680648

ABSTRACT

The Banff community summoned the TMA Banff Working Group to develop minimum diagnostic criteria (MDC) and recommendations for renal transplant TMA (Tx-TMA) diagnosis, which currently lacks standardized criteria. Using the Delphi method for consensus generation, 23 nephropathologists (panelists) with >3 years of diagnostic experience with Tx-TMA were asked to list light, immunofluorescence, and electron microscopic, clinical and laboratory criteria and differential diagnoses for Tx-TMA. Delphi was modified to include 2 validations rounds with histological evaluation of whole slide images of 37 transplant biopsies (28 TMA and 9 non-TMA). Starting with 338 criteria in R1, MDC were narrowed down to 24 in R8 generating 18 pathological, 2 clinical, 4 laboratory criteria, and 8 differential diagnoses. The panelists reached a good level of agreement (70%) on 76% of the validated cases. For the first time in Banff classification, Delphi was used to reach consensus on MDC for Tx-TMA. Phase I of the study (pathology phase) will be used as a model for Phase II (nephrology phase) for consensus regarding clinical and laboratory criteria. Eventually in Phase III (consensus of the consensus groups) and the final MDC for Tx-TMA will be reported to the transplantation community.


Subject(s)
Kidney Transplantation , Thrombotic Microangiopathies , Humans , Kidney Transplantation/adverse effects , Consensus , Kidney , Thrombotic Microangiopathies/diagnosis , Thrombotic Microangiopathies/etiology , Amines , Anticoagulants , Allografts
6.
Clin Transplant ; 34(8): e13998, 2020 08.
Article in English | MEDLINE | ID: mdl-32492226

ABSTRACT

In kidney transplantation, de novo donor-specific antibodies (DSA) correlate with poor graft survival, and Consensus Guidelines recommend a protocol biopsy. In pancreas transplantation, DSA are also associated with poor graft outcomes; however, there are no recommendations on protocol biopsies. We started an antibody screening protocol on pancreas transplant patients at 0, 3, 6, 12 months, and yearly. Patients with DSA or high MFI non-DSA were considered for protocol biopsies of both organs. Results: 143 pancreas recipients were screened. 84 patients had negative antibodies throughout the study, 11 patients were found to have antibodies at graft dysfunction, and 48 patients had positive antibodies at screening without acute organ dysfunction (study group). Among the 30 non-DSA patients, 9 had protocol simultaneous pancreas and kidney biopsies performed with negative results in all of them. In contrast, among the 18 DSA patients, 15 had these biopsies performed, and 47% presented with subclinical rejection of the kidney, the pancreas, or both. In addition, some of the DSA patients without a protocol biopsy presented with rejection during the first 15 months of follow-up. Conclusion: We conclude that protocol biopsies of both grafts may play a role in the follow-up of pancreas transplant patients with de novo DSA appearance.


Subject(s)
Pancreas Transplantation , Biopsy , Graft Rejection/diagnosis , Graft Rejection/etiology , Graft Survival , HLA Antigens , Humans , Isoantibodies , Tissue Donors
7.
Shock ; 56(6): 1019-1027, 2021 12 01.
Article in English | MEDLINE | ID: mdl-33882512

ABSTRACT

ABSTRACT: Acute kidney injury (AKI) is characterized by rapid loss of excretory function and is the clinical manifestation of several disorders affecting the kidney. The aim of the present study was to investigate the mechanism of action of Secretory Leukocyte Proteinase Inhibitor (SLPI) that protects the kidneys form AKI. In vivo and in vitro experiments were performed to assess the effect of SLPI on kidney injury. Animal models of kidney injury was generated by 40 min obstruction of kidney artery and vein (ischemia-reperfusion injury model) or daily administration of 60 mg/kg/day of gentamicine for 5 day (gentamicin-associated AKI model). For in vitro assessment, human renal epithelium HK-2 cells were cultured under serum starvation conditions or with tacrolimus. The administration of SLPI (250 µg/kg, i.p.) reduced elevated plasma creatinine and blood urea nitrogen levels, tissue myeloperoxidase content, and acute tubular necrosis induced by kidney damage. Furthermore, SLPI treatment reduced CD86, CD68, CD14, CCL2, TNFα, and IL-10 transcripts in kidney biopsies. To further analyze a direct effect of SLPI on renal epithelial cells, HK-2 cells from human renal epithelium were cultured under serum starvation conditions or with tacrolimus. Both conditions induced apoptosis of HK-2 cells which was reduced when SLPI was present in the culture medium. Furthermore, SLPI favored the proliferation and migration of HK-2 cells. An analysis of the gene profiles of HK-2 cells treated with calcineurin inhibitors affected inflammatory and non-inflammatory pathways that were reversed by SLPI. Among them, SLPI down modulated the expression of CCL2, SLC5A3, and BECN1 but up-regulated the expression of TLR4, ATF4, ATF6, HSP90B, BBC3 SLC2A1, and TNFRSF10B. Overall, these results suggest that SLPI, in addition to its activity on immune cells, may directly target tubular epithelial cells of the kidney to mediate the nephroprotective activity in AKI.


Subject(s)
Acute Kidney Injury/immunology , Acute Kidney Injury/prevention & control , Secretory Leukocyte Peptidase Inhibitor/physiology , Secretory Leukocyte Peptidase Inhibitor/therapeutic use , Animals , Humans , Male , Rats , Rats, Wistar
8.
Rev. nefrol. diál. traspl ; 43(2): 7-7, jun. 2023.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1515461

ABSTRACT

RESUMEN El camino para llegar a la diálisis peritoneal (DP) como tratamiento de la enfermedad renal crónica (ERC) avanzada estuvo jalonado por hitos a lo largo de la historia. Los conocimientos sobre la anatomía del peritoneo fueron aportados por los embalsamadores egipcios, Galeno (siglo II), y Vesalio (siglo XVI). Recién en 1628 Asellius Gaselli describe los capilares linfáticos abdominales. El siglo XIX fue rico en avances: se identificarn la célula como unidad de los seres vivos y el fenómeno de ósmosis (Dutrochet, 1828), los cristaloides y coloides y su pasaje o no a través de una membrana (Graham T, 1850), el flujo de solutos y partículas a través de la membrana peritoneal (v.Recklinghausen, 1863), la absorción de sustancias hipotónicas y el aumento del efluente con las hipertónicas (Wegner G, 1877), y experimentos en animales confirmaron que la remoción de fluidos y otras sustancias ocurría primariamente a través de vasos sanguíneos (Starling & Tubby, 1894). Pero recién en el siglo 20 se utilizó la DP como tratamiento. El primer intento de utilizar el peritoneo para tratar la uremia lo realizó Georg Ganter en 1923, primero en animales con ligadura de uréteres y luego en dos pacientes. Recién en 1937 se publicó el primer caso que sobrevivió a un "lavaje "peritoneal (Wear y col), pero fueron Fine, Frank y Seligman quienes inicialmente en perros nefrectomizados y luego en pacientes con injuria renal aguda (IRA) demostraron que el método no sólo era viable, sino también efectivo. Luego continuaron los progresos, sobre todo para pacientes con IRA, pero también en algunos casos con ERC avanzada: el doble frasco colgante (Maxwell M, 1959), la diálisis crónica intrahospitalaria con cicladora (Tenckoff y col, 1965), las bolsas plásticas para DP, hasta que en 1975 Moncrief y col pusieron en marcha la DP continua ambulatoria, y en 1981 se introdujo la DP automatizada. Los años noventa fueron de expansión de la DP, hoy instalada como una de las alternativas de tratamiento de la ERC avanzada.


ABSTRACT Milestones throughout history marked the path to reach peritoneal dialysis (PD) as a treatment for advanced chronic kidney disease (CKD). The Egyptian embalmers, Galen (2nd century) and Vesalius (16th century) provided knowledge about the anatomy of the peritoneum. It was not until 1628 that Asellius Gaselli described the abdominal lymphatic capillaries. The 19th century was rich in advances: the cell was identified as the unit of living beings and the phenomenon of osmosis (Dutrochet, 1828), crystalloids and colloids and their passage or not through a membrane (Graham T, 1850), the flow of solutes and particles through the peritoneal membrane (Recklinghausen, 1863), the absorption of hypotonic substances and the increase in effluent with hypertonic ones (Wegner G, 1877), and animal experiments confirmed that fluid removal and other substances occurred primarily through blood vessels (Starling & Tubby, 1894). But it was not until the 20th century that PD was applied as treatment. The first attempt to use the peritoneum to treat uremia was made by Georg Ganter in 1923, first in animals with ureteral ligation and then in two patients. It was not until 1937 that the first case that survived a peritoneal "lavage" was published (Wear et al), but it was Fine, Frank and Seligman who initially in nephrectomized dogs and later in patients with acute kidney injury (ARI) demonstrated that the method was not only viable, but also succesful. Then progress continued, especially for patients with ARI, but also in some cases with advanced CKD: the double hanging bottle (Maxwell M, 1959), chronic intrahospital dialysis with a cycler (Tenckoff et al, 1965), plastic bags for PD, until 1975 when Moncrief et al launched continuous ambulatory PD, and in 1981 automated PD was introduced. The 1990s saw the expansion of PD, to date installed as one of treatment alternatives for advanced CKD.

9.
Rev. nefrol. diál. traspl ; 41(1): 61-70, mar. 2021.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1377122

ABSTRACT

RESUMEN El trasplante de páncreas es un tratamiento alternativo para la diabetes. Sus modalidades e indicaciones son: 1) trasplante de páncreas simultáneo con riñón para pacientes con diabetes mellitus tipo 1 o con nefropatía diabética en estadio terminalen tratamiento sustitutivo o próximo al mismo; 2) trasplante de páncreas después de riñón parapacientes condiabetes mellitustipo 1 con un trasplante renal funcionante; 3) trasplante de páncreas aislado parapacientes con diabetes mellitustipo 1 con hipoglucemias aperceptivas que requieren internaciones o rescate de terceros. Algunos pacientes con diabetes mellitus tipo 2 seleccionados pueden ser candidatos a trasplante de páncreas. La selección de donantes es muy importante, el donante ideal es fallecido por traumatismo craneoencefálico, menor de 45 años, con un peso entre 30 y 90 kg, con un IMC menor a 30kg/m2, hemodinámicamente estable y sin antecedentes de paro cardiorespiratorio ni hipotensión sostenida. Hay varias estrategias de derivación de la función endócrina (sistémica y portal) y exócrina (entérica o vesical), la más utilizada es la derivación sistémica y entérica. En el manejo perioperatorio se destacan estrategias para mantener una buena presión de perfusión tisular, un control estricto de glucemia, para prevenir la trombosis del injerto debe implementarse un plan de antiagregación y anticoagulación, todo lo anterior junto a una profilaxis antibiótica, antifúngica y antiviral. Los esquemas clásicos de inmunosupresión incluyen una inducción con esteroides y anticuerpos deplecionantes de linfocitos T y un mantenimiento con un triple esquema con esteroides, tacrolimus y micofenolato. La clasificación de Banffdistingue rechazos celulares y humorales. La base del tratamiento del rechazo celular incluye pulsos de esteroides y anticuerpos deplecionantes de linfocitos T, mientras que los rechazos humorales requieren de plasmaféresis e inmunoglobulina endovenosa. Las principales complicaciones postoperatorias son el sangrado, la pancreatitis, la trombosis del injerto y las fístulas anastomóticas. En cuanto a los resultados, el trasplante de páncreas presenta, a cinco años, una supervivencia del paciente del 90% y un 77% del injerto pancreático. Las modalidades de trasplante solitario presentan menor supervivencia alejada del injerto. En Argentina hay una actividad de trasplante de páncreas de entre 60 y 80 trasplantes anuales. La reglamentación del INCUCAIprevé la inscripción anticipada en lista de espera de pacientes con nefropatía terminal con depuración de creatinina menor a 30ml/min.


ABSTRACT Pancreas transplantation is an alternative treatment for diabetes. Its modalities and indications are the following: 1) simultaneous pancreas and kidney transplantation: type 1 diabetes mellitus patients with end-stage diabetic nephropathy (in replacement treatment or close to it); 2) pancreas transplantation after kidney: type 1 diabetes mellitus patients with a functioning kidney transplant; 3) isolated pancreas transplantation: type 1 diabetes mellitus patients with unperceived hypoglycemia requiring hospitalization or rescue by third parties. Some of the screened type 2 diabetes mellitus patients may be pancreas transplantation candidates. Choosing a donor is very important: the ideal donor should be a deceased one who died due to intracranial injury, under 45 years of age, weighing between 30 and 90 kg, with a BMI below 30kg/m2, hemodynamically stable and having no history of cardiopulmonary arrest or sustained hypotension. There exist various strategies to divert the endocrine function (systemic and portal) and the exocrine function (vesical or enteric), systemic and enteric diversion being the most commonly used. Among the techniques which stand out during perioperative management, we could mention maintaining a good tissue perfusion, a strict glycemic control, an antiaggregation/anticoagulation plan to prevent graft thrombosis and antibiotic, antifungal and antiviral prophylactic treatment. Classic immunosuppression schemes consist of induction with T cell depleting steroids and antibodies and keeping a three-drug treatment including steroids, tacrolimus and mycophenolate. Banff classification draws a distinction between cellular and humoral rejection. The basis for cellular rejection treatment includes steroid-pulse therapy and T-cell depleting antibodies, while humoral rejection requires plasmapheresis and endovenous immunoglobulin. The main postoperative complications are bleeding, pancreatitis, graft thrombosis and anastomosis fistula. As for the results, the survival rate 5 years after pancreas transplantation is 90% for patients and 77% for pancreatic grafts. Isolated transplantation presents a lower long-term survival of the graft. In Argentina, between 60 and 80 pancreas transplants are performed every year. INCUCAI regulations provide for early registration on the waiting list for patients suffering from end-stage nephropathy with a creatinine clearance lower than 30 mL/min.

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