Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.3.16 (calcineurin)
 17,112 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The clinical features of transplant-associated thrombotic microangiopathy (TA-TMA) include microangiopathic hemolytic anemia, consumptive thrombocytopenia, and organ dysfunction caused by thrombi in microvessels. The pathogenesis of TA-TMA is based on vascular endothelial insults caused by various factors, including chemotherapy and total-body irradiation used for transplant pre-conditioning, calcineurin inhibitors, cytokines release associated with infection, and complement factors. The incidence of TA-TMA is approximately 15-30% among allogeneic transplant patients, and the mortality rate reaches 100% in severe cases with multi-organ dysfunction. This review describes the current understanding of the pathogenesis, diagnostic criteria, and treatment strategies of this potentially lethal transplant-associated complication.
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PMID:[Management of transplant-associated thrombotic microangiopathy]. 3030 40

Thrombotic microangiopathy (TMA) after renal transplantation can be a diagnostic challenge. TMA can occur with calcineurin inhibitors, allograft rejection, infection, mutations in complement regulatory proteins and autoimmunity. A 52-year-old male renal transplant recipient presented with extensive deep vein thrombosis. He developed transfusion-dependent microangiopathic haemolytic anaemia with thrombocytopenia. He did not respond calcineurin inhibitor cessation, eculizumab or plasma exchange. ADAMTS13 and complement levels were normal. Infection and autoimmune screens were negative. A diagnosis of metastatic adenocarcinoma was made on bone marrow biopsy. This represents a rare case of malignancy-associated TMA in a renal transplant recipient. Early diagnosis can facilitate the prompt initiation of chemotherapy which is the only treatment option.
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PMID:Metastatic lung adenocarcinoma- associated thrombotic microangiopathy in a renal transplant recipient. 3056 42

Transplant-associated thrombotic microangiopathy (TA-TMA) is an endothelial damage syndrome that is increasingly identified as a complication of both autologous and allogeneic hematopoietic cell transplantation (HCT) in children. If not promptly diagnosed and treated, TA-TMA can lead to significant morbidity (e.g., permanent renal injury) or mortality. However, as the recognition of the early stages of TA-TMA may be difficult, we propose a TA-TMA "triad" of hypertension, thrombocytopenia (or platelet transfusion refractoriness), and elevated lactate dehydrogenase (LDH). While not diagnostic, this triad should prompt further evaluation for TA-TMA. There is increased understanding of the risk factors for the development of TA-TMA, including those which are inherent (e.g., race, genetics), transplant approach-related (e.g., second HCT, use of HLA-mismatched donors), and related to post-transplant events (e.g., receipt of calcineurin inhibitors, development of graft-vs. -host-disease, or certain infections). This understanding should lead to enhanced screening for TA-TMA signs and symptoms in high-risk patients. The pathophysiology of TA-TMA is complex, resulting from a cycle of activation of endothelial cells to produce a pro-coagulant state, along with activation of antigen-presenting cells and lymphocytes, as well as activation of the complement cascade and microthrombi formation. This has led to the formulation of a "Three-Hit Hypothesis" in which patients with either an underlying predisposition to complement activation or pre-existing endothelial injury (Hit 1) undergo a toxic conditioning regimen causing endothelial injury (Hit 2), and then additional insults are triggered by medications, alloreactivity, infections, and/or antibodies (Hit 3). Understanding this cycle of injury permits the development of a specific TA-TMA treatment algorithm designed to treat both the triggers and the drivers of the endothelial injury. Finally, several intriguing approaches to TA-TMA prophylaxis have been identified. Future work on the development of a single diagnostic test with high specificity and sensitivity, and the development of a robust risk-scoring system, will further improve the management of this serious post-transplant complication.
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PMID:Transplant-Associated Thrombotic Microangiopathy in Pediatric Hematopoietic Cell Transplant Recipients: A Practical Approach to Diagnosis and Management. 3102 73

Transplant-associated thrombotic microangiopathy (TA-TMA) is a rare complication of hematopoietic stem cell transplantation (HSCT) with variable presentations. TA-TMA has often been described as a diagnosis of exclusion but a renal biopsy is rarely pursued to confirm the diagnosis, an essential step for our patient with renally limited TMA. We report a case report from the onconephrology clinic and review the literature associated with TA-TMA as it relates to diagnosis and treatment. A 45-year-old woman with acute myeloid leukemia and stage 3 chronic kidney disease underwent a matched unrelated donor allogenic HSCT. Postoperatively, she developed gastrointestinal graft versus host disease (GvHD) and was treated with tacrolimus, sirolimus, budesonide, and beclomethasone. Following discharge, she developed uncontrolled hypertension and required losartan, amlodipine, carvedilol, clonidine patch, and hydralazine as needed. On day 180 post-transplant, she developed lower extremity edema and acute kidney injury (AKI) with creatinine increasing to 2 mg/dL. On day 480 post-transplant, she developed worsening thrombocytopenia, anemia, new hematuria, left flank pain, and worsening renal function with creatinine peaking to 6 mg/dL. Peripheral smear revealed no schistocytes, lactate dehydrogenase of 265 mg/dL, and urinalysis with 100 mg/dL protein. ADAMTS 13 activity was normal (92%) and no inhibitor was detected. She became anuric and was started on hemodialysis. Renal biopsy revealed glomerular changes consistent with TA-TMA. During HSCT, systemic vascular endothelial injury triggers microangiopathic hemolytic anemia, platelet consumption, injury of glomerular endothelial cells and fibrin occluded renal capillaries. Thus, TA-TMA should be considered in HSCT patients with elevated LDH, proteinuria, hypertension, and AKI. However, a diagnosis is difficult to confirm without a renal biopsy. Treatment involves discontinuing potentially toxic agents such as calcineurin inhibitors and sirolimus, prescribing adequate antimicrobial treatment, and using renal replacement therapy if needed. A renal biopsy early in the course of disease not only confirms the diagnosis, but may limit the extent of disease.
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PMID:Thrombotic Microangiopathy With Granulomatosis Interstitial Nephritis in an Allogenic Bone Marrow Transplant Patient: A Case Report and Review of the Literature. 3230 Mar 93


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