RESUMO
BACKGROUND: Vitamin C deficiency is found in patients with variable kidney diseases. However, the role of vitamin C as an epigenetic regulator in renal homeostasis and pathogenesis remains largely unknown. METHODS: We showed that vitamin C deficiency leads to acute tubular necrosis (ATN) using a vitamin C-deficient mouse model (Gulo knock-out). DNA/RNA epigenetic modifications and injured S3 proximal tubule cells were identified in the vitamin C-deficient kidneys using whole-genome bisulfite sequencing, methylated RNA immunoprecipitation sequencing, and single-cell RNA sequencing. RESULTS: Integrated evidence suggested that epigenetic modifications affected the proximal tubule cells and fenestrated endothelial cells, leading to tubule injury and hypoxia through transcriptional regulation. Strikingly, loss of DNA hydroxymethylation and DNA hypermethylation in vitamin C-deficient kidneys preceded the histologic sign of tubule necrosis, indicating the causality of vitamin C-induced epigenetic modification in ATN. Consistently, prophylactic supplementation of an oxidation-resistant vitamin C derivative, ascorbyl phosphate magnesium, promoted DNA demethylation and prevented the progression of cisplatin-induced ATN. CONCLUSIONS: Vitamin C played a critical role in renal homeostasis and pathogenesis in a mouse model, suggesting vitamin supplementation may be an approach to lower the risk of kidney injury.
Assuntos
Deficiência de Ácido Ascórbico , Necrose Tubular Aguda , Animais , Ácido Ascórbico/farmacologia , Modelos Animais de Doenças , Células Endoteliais , Epigênese Genética , Feminino , Humanos , Necrose Tubular Aguda/etiologia , Masculino , Camundongos , Necrose , RNARESUMO
Acute kidney injury (AKI) is the main obstacle that limits the use of cisplatin in cancer treatment. Proton pump inhibitors (PPIs), the most commonly used class of medications for gastrointestinal complications in cancer patients, have been reported to cause adverse renal events. However, the effect of PPIs on cisplatin-induced AKI remains unclear. Herein, the effect and mechanism of lansoprazole (LPZ), one of the most frequently prescribed PPIs, on cisplatin-induced AKI were investigated in vivo and in vitro. C57BL/6 mice received a single intraperitoneal (i.p.) injection of cisplatin (18 mg/kg) to induce AKI, and LPZ (12.5 or 25 mg/kg) was administered 2 hours prior to cisplatin administration and then once daily for another 2 days via i.p. injection. The results showed that LPZ significantly aggravated the tubular damage and further increased the elevated levels of serum creatinine and blood urea nitrogen induced by cisplatin. However, LPZ did not enhance cisplatin-induced tubular apoptosis, as evidenced by a lack of significant change in mRNA and protein expression of Bax/Bcl-2 ratio and TUNEL staining. Notably, LPZ increased the number of necrotic renal tubular cells compared to that by cisplatin treatment alone, which was further confirmed by the elevated necroptosis-associated protein expression of RIPK1, p-RIPK3 and p-MLKL. Furthermore, LPZ deteriorated cisplatin-induced inflammation, as revealed by the increased mRNA expression of pro-inflammatory factors including, NLRP3, IL-1ß, TNF-α and caspase 1, as well as neutrophil infiltration. Consistently, in in vitro study, LPZ increased HK-2 cell death and enhanced inflammation, compared with cisplatin treatment alone. Collectively, our results demonstrate that LPZ aggravates cisplatin-induced AKI, and necroptosis may be involved in the exacerbation of kidney damage.
Assuntos
Antineoplásicos/efeitos adversos , Cisplatino/efeitos adversos , Necrose Tubular Aguda/etiologia , Necrose Tubular Aguda/metabolismo , Lansoprazol/efeitos adversos , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/patologia , Animais , Apoptose/efeitos dos fármacos , Modelos Animais de Doenças , Sinergismo Farmacológico , Necrose Tubular Aguda/patologia , CamundongosRESUMO
BACKGROUND: Macroscopic hematuria-associated acute kidney injury (AKI) is a well-known complication of immunoglobulin A (IgA) nephropathy. In such cases, intratubular obstruction by red blood cell (RBC) casts and acute tubular necrosis are mainly observed pathologically. Herein, we report the case of a patient with IgA nephropathy presenting with AKI following an episode of macrohematuria. The patient presented with severe renal tubular hemosiderosis and acute tubular necrosis and without any obvious obstructive RBC casts. CASE PRESENTATION: A 68-year-old woman, who was diagnosed with IgA nephropathy on renal biopsy 6 years ago, was admitted to our hospital after an episode of macroscopic glomerular hematuria and AKI following upper respiratory tract infection. Renal biopsy showed mesangial proliferation of the glomeruli, including crescent formation in 17 % of the glomeruli, and acute tubular necrosis without obvious hemorrhage or obstructive RBC casts. The application of Perls' Prussian blue stain showed hemosiderin deposition in the renal proximal tubular cells. Immunofluorescence showed granular mesangial deposits of IgA and C3. Based on these findings, she was diagnosed with acute tubular necrosis with a concurrent IgA nephropathy flare-up. Moreover, direct tubular injury by heme and iron was considered to be the cause of AKI. She was treated with intravenous pulse methylprednisolone followed by oral prednisolone. Thereafter, the gross hematuria gradually faded, and her serum creatinine levels decreased. CONCLUSIONS: IgA nephropathy presenting with acute kidney injury accompanied by macrohematuria may cause renal hemosiderosis and acute tubular necrosis without obstructive RBC casts. Hemosiderosis may be a useful indicator for determining the pathophysiology of macroscopic hematuria-associated AKI. However, renal hemosiderosis may remain undiagnosed. Thus, Perls' Prussian blue iron staining should be more widely used in patients presenting with hematuria.
Assuntos
Glomerulonefrite por IGA/complicações , Hematúria/etiologia , Hemossiderose/etiologia , Necrose Tubular Aguda/etiologia , Idoso , Eritrócitos/patologia , Feminino , Glomerulonefrite por IGA/patologia , Hematúria/complicações , Hemossiderose/complicações , Hemossiderose/patologia , Humanos , Necrose Tubular Aguda/patologiaRESUMO
BACKGROUND: Kidney injury associated with cold storage is a determinant of delayed graft function and the long-term outcome of transplanted kidneys, but the underlying mechanism remains elusive. We previously reported a role of protein kinase C-δ (PKCδ) in renal tubular injury during cisplatin nephrotoxicity and albumin-associated kidney injury, but whether PKCδ is involved in ischemic or transplantation-associated kidney injury is unknown. METHODS: To investigate PKCδ's potential role in injury during cold storage-associated transplantation, we incubated rat kidney proximal tubule cells in University of Wisconsin (UW) solution at 4°C for cold storage, returning them to normal culture medium at 37°C for rewarming. We also stored kidneys from donor mice in cold UW solution for various durations, followed by transplantation into syngeneic recipient mice. RESULTS: We observed PKCδ activation in both in vitro and in vivo models of cold-storage rewarming or transplantation. In the mouse model, PKCδ was activated and accumulated in mitochondria, where it mediated phosphorylation of a mitochondrial fission protein, dynamin-related protein 1 (Drp1), at serine 616. Drp1 activation resulted in mitochondrial fission or fragmentation, accompanied by mitochondrial damage and tubular cell death. Deficiency of PKCδ in donor kidney ameliorated Drp1 phosphorylation, mitochondrial damage, tubular cell death, and kidney injury during cold storage-associated transplantation. PKCδ deficiency also improved the repair and function of the renal graft as a life-supporting kidney. An inhibitor of PKCδ, δV1-1, protected kidneys against cold storage-associated transplantation injury. CONCLUSIONS: These results indicate that PKCδ is a key mediator of mitochondrial damage and renal tubular injury in cold storage-associated transplantation and may be an effective therapeutic target for improving renal transplant outcomes.
Assuntos
Temperatura Baixa/efeitos adversos , Dinaminas/metabolismo , Transplante de Rim , Necrose Tubular Aguda/etiologia , Túbulos Renais Proximais/enzimologia , Preservação de Órgãos/métodos , Proteína Quinase C-delta/fisiologia , Animais , Apoptose , Divisão Celular , Células Cultivadas , Ativação Enzimática , Necrose Tubular Aguda/enzimologia , Túbulos Renais Proximais/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias/enzimologia , Fosforilação , Proteína Quinase C-delta/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Processamento de Proteína Pós-Traducional , RatosRESUMO
BACKGROUND AND AIM: For appropriate management of acute kidney injury (AKI) in cirrhotic patients, accurate differentiation of the types of AKI, prerenal azotemia (PRA), hepatorenal syndrome (HRS), and acute tubular necrosis (ATN) is very important. Urine N-acetyl-ß-D-glucosaminidase (NAG) has been proposed as a good tubular injury marker in many studies, but its efficacy in cirrhosis is unclear. This study was performed to evaluate the usefulness of urine NAG in patients with decompensated cirrhosis. METHODS: In 114 hospitalized patients with decompensated cirrhosis, we assessed serum creatinine, cystatin C, and urine NAG levels as markers for AKI differentiation and development and patient mortality. RESULTS: Thirty patients diagnosed with AKI at baseline had significantly higher serum creatinine and cystatin C levels, urine NAG levels, and Child-Pugh scores than those without AKI. Only urine NAG levels were significantly higher in patients with ATN than those with PRA or HRS (116.1 ± 46.8 U/g vs 39.4 ± 20.2 or 54.0 ± 19.2 U/g urinary creatinine, all P < 0.05). During a median follow up of 6.1 months, AKI developed in 17 of 84 patients: PRA in nine, HRS in six, and ATN in three. Higher serum cystatin C and urine NAG levels were independent predictors of AKI development in patients with decompensated cirrhosis. Survival was significantly associated with low serum cystatin C and urine NAG levels. CONCLUSION: Serum cystatin C and urine NAG levels are useful to differentiate types of AKI and are strong predictors for AKI development and mortality in patients with decompensated cirrhosis.
Assuntos
Acetilglucosaminidase/urina , Cistatina C/sangue , Nefropatias/sangue , Nefropatias/urina , Cirrose Hepática/fisiopatologia , Injúria Renal Aguda/sangue , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/urina , Idoso , Azotemia/sangue , Azotemia/etiologia , Azotemia/urina , Biomarcadores/sangue , Biomarcadores/urina , Creatinina/sangue , Feminino , Síndrome Hepatorrenal/sangue , Síndrome Hepatorrenal/etiologia , Síndrome Hepatorrenal/urina , Humanos , Nefropatias/etiologia , Necrose Tubular Aguda/sangue , Necrose Tubular Aguda/etiologia , Necrose Tubular Aguda/urina , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Taxa de SobrevidaRESUMO
Hyperoxaluria can result in oxalate nephropathy with intratubular calcium oxalate crystallization and acute tubular injury. Primary inherited enzymatic deficiency or secondary causes such as excessive dietary intake, enteric increased absorption, or high doses of vitamin C, which is metabolized to oxalate, may underlie hyperoxaluria and oxalate nephropathy. We report a case of acute kidney injury due to oxalate nephropathy in a patient using chelating therapy with oral ethylenediamine tetra acetic acid (EDTA), intravenous supplementation with vitamin C, and chronic diarrhea and discuss the potential kidney damage these factors can cause in particular settings. To our knowledge, this is the first report suggesting an association between oral EDTA and oxalate nephropathy.
Assuntos
Injúria Renal Aguda/etiologia , Ácido Ascórbico/efeitos adversos , Quelantes de Cálcio/efeitos adversos , Oxalato de Cálcio , Diarreia/complicações , Ácido Edético/efeitos adversos , Hiperoxalúria/etiologia , Vitaminas/efeitos adversos , Injúria Renal Aguda/patologia , Injúria Renal Aguda/terapia , Idoso , Humanos , Necrose Tubular Aguda/etiologia , Necrose Tubular Aguda/patologia , Masculino , Diálise RenalRESUMO
Transurethral resection of the prostate is currently the gold standard for the surgical treatment of the benign prostatic hyperplasia. This surgery may lead transurethral resection of the prostate (TURP) syndrome and in some cases, acute tubular necrosis can develop. We report a patient who developed hyponatremia, hemolysis and oliguric acute renal failure as a major complication following TURP using glycine as irrigating fluid.A 64-year-old man was admitted for a prostate resection procedure. Physical examination revealed a healthy elderly man. Preoperative laboratory data showed serum sodium 140 mEq/L, blood urea nitrogen (BUN) 0.6 g/L, creatinine 0.7 mg/dL and hemoglobin 12.9 g/dL. Few hours after, the patient becomes incoherent and developed oliguria, nausea and vomiting. The laboratory data revealed rapidly elevating BUN and creatinine levels (BUN 2.4 g/L; creatinine 6.1 mg/dL), the serum sodium concentration decreased by 14 meq/L. A decreased hemoglobin level (7.4 g/dL) with an elevated lactate dehydrogenase level (665 U/L) was observed. Renal ultrasonography was normal. The diagnosis of acute tubular necrosis complicating TURP syndrome was retained. The hyponatremia was slowly corrected to 132 mmol/L by diuresis and fluid restriction. The renal function recovered after four hemodialysis sessions. Using glycine as an irrigant for TURP may cause hyponatremia, hemolysis and also acute renal failure, especially in patients with longer resection time. It is necessary to carry out every effort to shorten resection time and avoid extravasation during surgery.
Assuntos
Glicina/uso terapêutico , Necrose Tubular Aguda/etiologia , Irrigação Terapêutica/efeitos adversos , Ressecção Transuretral da Próstata/efeitos adversos , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , Glicina/efeitos adversos , Humanos , Hiponatremia/diagnóstico , Hiponatremia/etiologia , Necrose Tubular Aguda/diagnóstico , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/cirurgia , Síndrome , Irrigação Terapêutica/métodosRESUMO
Noninvasive methods to diagnose and differentiate acute cellular rejection from acute tubular necrosis or acute calcineurin inhibitor toxicity are still missing. Because T lymphocytes play a decisive role in early states of rejection, we investigated the suitability and feasibility of antibody-mediated contrast-enhanced ultrasound by using microbubbles targeted to CD3(+) , CD4(+) , or CD8(+) T cells in different models of renal disease. In an established rat renal transplantation model, CD3-mediated ultrasound allows the detection of acute rejection as early as on postoperative day 2. Ultrasound signal intensities increased with the severity of inflammation. Further, an early response to therapy could be monitored by using contrast-enhanced sonography. Notably, acute tubular necrosis occurring after ischemia-reperfusion injury as well as acute calcineurin inhibitor toxicity could easily be differentiated. Finally, the quantified ultrasound signal correlated significantly with the number of infiltrating T cells obtained by histology and with CD3 mRNA levels, as well as with chemokine CXCL9, CXCL11, and CCL19 mRNA but not with KIM-1 mRNA expression, thereby representing the severity of graft inflammation but not the degree of kidney injury. In summary, we demonstrate that antibody-mediated contrast-enhanced ultrasound targeting T lymphocytes could be a promising tool for an easy and reproducible assessment of acute rejection after renal transplantation.
Assuntos
Complexo CD3/imunologia , Rejeição de Enxerto/diagnóstico , Transplante de Rim/efeitos adversos , Imagem Molecular/métodos , Traumatismo por Reperfusão/complicações , Linfócitos T/imunologia , Ultrassonografia/métodos , Doença Aguda , Animais , Inibidores de Calcineurina/toxicidade , Meios de Contraste/metabolismo , Rejeição de Enxerto/diagnóstico por imagem , Rejeição de Enxerto/etiologia , Isoanticorpos/toxicidade , Necrose Tubular Aguda/diagnóstico , Necrose Tubular Aguda/diagnóstico por imagem , Necrose Tubular Aguda/etiologia , Masculino , Microbolhas , Ratos , Ratos Endogâmicos BN , Ratos Endogâmicos Lew , Traumatismo por Reperfusão/cirurgia , Transplante HomólogoRESUMO
BACKGROUND: Enteric hyperoxaluria (EH) occurs with a rate of 5-24% in patients with inflammatory bowel disease, ileal resection and modern bariatric surgery. The excessive absorption of calcium oxalate causes chronic kidney disease (CKD) in patients with EH. In the literature, a single experience was reported in combined intestine-kidney transplantation (CIKTx) in patients with CKD due to EH. METHODS: After a report of 2 successful cases of CIKTx in patients with EH and CKD, one was performed at our center in a 59-year-old Caucasian female who developed intestinal failure with total parenteral nutrition (TPN) dependence after a complication post-bariatric surgery. Before CIKTx, she underwent kidney transplantation alone (KTA) twice, which failed due to oxalate nephropathy. RESULTS: In July 2014, the patient underwent CIKTx and bilateral allograft nephrectomy to avoid EH and oxalate stone burden. The postoperative course was complicated with acute tubular necrosis due to the use of high pressors related to perioperative bleeding. The patient was discharged 79 days after CIKTx with a serum creatinine (sCr) of 1.2 mg/dl and free of TPN. Her sCr increased at 7 months and a renal biopsy showed oxalate nephropathy. SLC26A6 (oxalate transporter) staining was significantly diminished in native duodenum/rectum as well as in intestinal allograft compared to control. CONCLUSIONS: KTA in patients with CKD secondary to EH should not be recommended due to high risk of recurrence. Although other centers showed good long-term outcomes in CIKTx, our patient experienced recurrence of EH due to oxalate transporter defect, early kidney allograft dysfunction and prolonged antibiotic use.
Assuntos
Oxalato de Cálcio/farmacocinética , Derivação Gástrica/efeitos adversos , Hiperoxalúria/cirurgia , Intestinos/transplante , Transplante de Rim/efeitos adversos , Insuficiência Renal Crônica/cirurgia , Aloenxertos/patologia , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Biópsia , Transfusão de Componentes Sanguíneos , Perda Sanguínea Cirúrgica/prevenção & controle , Oxalato de Cálcio/urina , Ceco/cirurgia , Creatinina/sangue , Função Retardada do Enxerto/etiologia , Feminino , Taxa de Filtração Glomerular , Humanos , Hiperoxalúria/complicações , Hiperoxalúria/patologia , Volvo Intestinal/etiologia , Volvo Intestinal/cirurgia , Intestinos/patologia , Rim/patologia , Necrose Tubular Aguda/etiologia , Proteínas de Membrana Transportadoras/metabolismo , Pessoa de Meia-Idade , Nutrição Parenteral , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/terapia , Recidiva , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/patologia , Transportadores de Sulfato , Transplante Homólogo/efeitos adversos , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/etiologia , Vasoconstritores/efeitos adversos , Vasoconstritores/uso terapêuticoRESUMO
The kidney plays a primary role in maintaining homeostasis and detoxification of numerous hydrophilic xenobiotics as well as endogenous compounds. Because the kidney is exposed to a larger proportion and higher concentration of drugs and toxins than other organs through the secretion of ionic drugs by tubular organic ion transporters across the luminal membranes of renal tubular epithelial cells, and through the reabsorption of filtered toxins into the lumen of the tubule, these cells are at greater risk for injury. In fact, drug-induced kidney injury is a serious problem in clinical practice and accounts for roughly 20% of cases of acute kidney injury (AKI) among hospitalized patients. Therefore, its early detection is becoming more important. Usually, drug-induced AKI consists of two patterns of renal injury: acute tubular necrosis (ATN) and acute interstitial nephritis (AIN). Whereas AIN develops from medications that incite an allergic reaction, ATN develops from direct toxicity on tubular epithelial cells. Among several cellular mechanisms underlying ATN, oxidative stress plays an important role in progression to ATN by activation of inflammatory response via proinflammatory cytokine release and inflammatory cell accumulation in tissues. This review provides an overview of drugs associated with AKI, the role of oxidative stress in drug-induced AKI, and a biomarker for drug-induced AKI focusing on oxidative stress.
Assuntos
Injúria Renal Aguda/fisiopatologia , Necrose Tubular Aguda/fisiopatologia , Nefrite Intersticial/fisiopatologia , Estresse Oxidativo/fisiologia , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/metabolismo , Animais , Biomarcadores/metabolismo , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/complicações , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Humanos , Necrose Tubular Aguda/etiologia , Necrose Tubular Aguda/metabolismo , Lipocalina-2/metabolismo , Nefrite Intersticial/etiologiaRESUMO
Acute tubular necrosis (ATN), especially from toxic injury is frequently accompanied by tubular casts and crystals. Myeloma casts, myoglobin, red blood cell and granular casts are well described. However, bile casts in tubules are rarely seen. We describe a case of Tribulus terrestris toxicity in a young healthy male, presenting with severe hyperbilirubinemia followed by acute renal failure and bile containing casts in the tubules. Tribulus terrestris is an herb often used by athletes as a nutritional supplement for performance enhancement. Although it is thought to be relatively safe, serious side effects have been reported before. Our aim is to increase awareness of the potential toxicities of performance enhancing herbal medications. These are often sold over-the-counter and therefore casually used, especially by young healthy individuals. Beneficial effects are controversial. Under-reporting by patients and infrequent documentation by health-care providers can delay diagnosis. We elaborately describe the kidney biopsy findings in Tribulus terrestris toxicity, and also provide a concise overview of the spectrum of tubular casts and their staining patterns, found in various kidney diseases.
Assuntos
Injúria Renal Aguda/etiologia , Hiperbilirrubinemia/etiologia , Tribulus/intoxicação , Adulto , Humanos , Rim/patologia , Necrose Tubular Aguda/etiologia , MasculinoRESUMO
AIM: Delayed graft function is an early complication leading to impaired creatinine clearance, urine formation and determinant of long term graft outcome. The aim of the present study was to determine the earliest predictive cut-off value of uKIM-1 level in patients with delayed graft function and acute tubular necrosis. METHODS: We have determined the serial urinary KIM-1 normalized to urinary creatinine (uKIM-1, pg/mg) level at 0, 6, 12, 18, 24 and 48 h of post-transplant by ELISA methods. RESULT: The normalized uKIM-1 and AUC-ROC, of uKIM-1 were progressively increased up to 48 h in both delayed graft function (DGF) and immediate graft function (IGF). The u KIM-1 values were significantly high at 6, 12, 18, 24 and 48 h in patients with DGF as compared to that of IGF except at half an hour post-transplant values. Although, progressive increase in uKIM-1 values were observed in both groups of patients; there was an overlap of values between two groups up to 12 h. The earliest non-overlapping values of uKIM-1 between the groups were observed at 18 h onwards and minimum difference of 923.43 pg/mg. The earliest predictive AUC-ROC of uKIM-1 in patients with DGF without overlap with IGF was also observed at 18 h post-transplant with specificity of 100% and sensitivity of 89.9%. CONCLUSION: Serial uKIM-1 measurement can be used as non-invasive diagnostic biomarkers to predict the incident of DGF in living donor renal transplant recipients. At 18(th) post-transplant hour uKIM-1 can predict DGF with 100% specificity and 89.9% sensitivity with a cut-off value of normalized KIM-1 of 923.43 pg/mg.
Assuntos
Função Retardada do Enxerto/urina , Transplante de Rim/efeitos adversos , Necrose Tubular Aguda/urina , Doadores Vivos , Glicoproteínas de Membrana/urina , Aloenxertos , Área Sob a Curva , Biomarcadores/urina , Função Retardada do Enxerto/diagnóstico , Função Retardada do Enxerto/etiologia , Diagnóstico Precoce , Ensaio de Imunoadsorção Enzimática , Receptor Celular 1 do Vírus da Hepatite A , Humanos , Transplante de Rim/métodos , Necrose Tubular Aguda/diagnóstico , Necrose Tubular Aguda/etiologia , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Receptores Virais , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento , UrináliseRESUMO
Stem cell transplantation is now a routine and successful therapeutic method in many hematopoietic disorders and cancers. Unfortunately, toxicity of the procedure significantly worsens the outcomes, with acute and chronic kidney injury among the others. Etiology of kidney failure is multifactorial with nephrotoxicity of drugs, septic complications, sinusoidal occlusion syndrome, thrombotic microangiopathy and acute/chronic graft-versus-host disease (GvHD). Understanding these syndromes enables early recognition and proper intervention that can reduce incidence and severity of kidney injury and improve outcomes.
Assuntos
Injúria Renal Aguda/etiologia , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Necrose Tubular Aguda/etiologia , Humanos , Falência Renal Crônica/etiologia , Insuficiência Renal Crônica/etiologiaRESUMO
Toll-like receptor-4 (TLR-4) has been increasingly recognized as playing a critical role in the pathogenesis of ischemia-reperfusion injury (IRI) of renal grafts. This review provides a detailed overview of the new understanding of the involvement of TLR-4 in ischemia-reperfusion injury of renal grafts and its clinical significance in renal transplantation. TLR-4 not only responds to exogenous microbial motifs but can also recognize molecules which are released by stressed and necrotic cells, as well as degraded products of endogenous macromolecules. Upregulation of TLR-4 is found in tubular epithelial cells, vascular endothelial cells, and infiltrating leukocytes during renal ischemia-reperfusion injury, which is induced by massive release of endogenous damage-associated molecular pattern molecules such as high-mobility group box chromosomal protein 1. Activation of TLR-4 promotes the release of proinflammatory mediators, facilitates leukocyte migration and infiltration, activates the innate and adaptive immune system, and potentiates renal fibrosis. TLR-4 inhibition serves as the target of pharmacological agents, which could attenuate ischemia-reperfusion injury and associated delayed graft function and allograft rejection. There is evidence in the literature showing that targeting TLR-4 could improve long-term transplantation outcomes. Given the pivotal role of TLR-4 in ischemia-reperfusion injury and associated delayed graft function and allograft rejection, inhibition of TLR-4 using pharmacological agents could be beneficial for long-term graft survival.
Assuntos
Transplante de Rim/efeitos adversos , Traumatismo por Reperfusão/fisiopatologia , Receptor 4 Toll-Like/fisiologia , Animais , Biglicano/fisiologia , Rejeição de Enxerto , Proteína HMGB1/fisiologia , Proteínas de Choque Térmico/fisiologia , Humanos , Imunidade Inata/fisiologia , Necrose Tubular Aguda/etiologia , Fator 88 de Diferenciação Mieloide/fisiologia , Polimorfismo Genético , Transdução de Sinais , Receptor 4 Toll-Like/genéticaRESUMO
We report the case of a 69-year-old man who presented with acute kidney injury in the setting of community-acquired Clostridium difficile-associated diarrhea and biopsy-proven acute oxalate nephropathy. We discuss potential mechanisms, including increased colonic permeability to oxalate. We conclude that C difficile-associated diarrhea is a potential cause of acute oxalate nephropathy.
Assuntos
Oxalato de Cálcio/metabolismo , Clostridioides difficile , Colo/metabolismo , Diarreia , Hidratação/métodos , Necrose Tubular Aguda , Metronidazol/administração & dosagem , Doença Aguda , Idoso , Anti-Infecciosos/administração & dosagem , Biópsia , Clostridioides difficile/efeitos dos fármacos , Clostridioides difficile/isolamento & purificação , Diarreia/complicações , Diarreia/microbiologia , Diarreia/fisiopatologia , Humanos , Rim/patologia , Testes de Função Renal , Necrose Tubular Aguda/diagnóstico , Necrose Tubular Aguda/etiologia , Necrose Tubular Aguda/fisiopatologia , Necrose Tubular Aguda/terapia , Masculino , Permeabilidade , Probióticos/administração & dosagem , Resultado do TratamentoRESUMO
BACKGROUND: To describe recent insights into glomerular haemodynamics in septic acute kidney injury (AKI). METHODS: We reviewed the literature with particular emphasis on recent findings in animal experiments and human studies in relation to renal macro- and micro-renal haemodynamics during septic AKI. RESULTS: The dominant paradigm is that septic AKI is due to decreased renal perfusion with ischaemic loss of glomerular filtration rate (GFR), ischaemic tubular cell injury and acute tubular necrosis (ATN). However, recent experimental and human studies challenge this view of the pathogenesis of septic AKI. In addition, rapid post-mortem and experimental histological studies do not support ATN as the histological substrate of septic AKI. Finally, more recent experimental evidence suggests that changes in the glomerular and peri-glomerular haemodynamics provide a more likely explanation for the loss of GFR seen in the early phases of septic AKI. CONCLUSIONS: Despite a long-standing paradigm that septic AKI is due to renal hypo-perfusion and associated ATN, experimental and human studies increasingly suggest that changes in the state of the glomerular and peri-glomerular micro-vasculature are a more likely additional explanation for this condition.
Assuntos
Taxa de Filtração Glomerular , Glomérulos Renais/inervação , Necrose Tubular Aguda/fisiopatologia , Sepse/complicações , Sistema Nervoso Simpático/patologia , Animais , Humanos , Glomérulos Renais/fisiopatologia , Necrose Tubular Aguda/etiologiaRESUMO
Regeneration of injured tubular cells occurs after acute tubular necrosis primarily from intrinsic renal cells. This may occur from a pre-existing intratubular stem/progenitor cell population or from any surviving proximal tubular cell. In this study, we characterize a CD24-, CD133-, and vimentin-positive subpopulation of cells scattered throughout the proximal tubule in normal human kidney. Compared to adjacent 'normal' proximal tubular cells, these CD24-positive cells contained less cytoplasm, fewer mitochondria, and no brush border. In addition, 49 marker proteins are described that are expressed within the proximal tubules in a similar scattered pattern. For eight of these markers, we confirmed co-localization with CD24. In human biopsies of patients with acute tubular necrosis (ATN), the number of CD24-positive tubular cells was increased. In both normal human kidneys and the ATN biopsies, around 85% of proliferating cells were CD24-positive - indicating that this cell population participates in tubular regeneration. In healthy rat kidneys, the novel cell subpopulation was absent. However, upon unilateral ureteral obstruction (UUO), the novel cell population was detected in significant amounts in the injured kidney. In summary, in human renal biopsies, the CD24-positive cells represent tubular cells with a deviant phenotype, characterized by a distinct morphology and marker expression. After acute tubular injury, these cells become more numerous. In healthy rat kidneys, these cells are not detectable, whereas after UUO, they appeared de novo - arguing against the notion that these cells represent a pre-existing progenitor cell population. Our data indicate rather that these cells represent transiently dedifferentiated tubular cells involved in regeneration.
Assuntos
Proliferação de Células , Necrose Tubular Aguda/patologia , Túbulos Renais Proximais/ultraestrutura , Regeneração , Antígeno AC133 , Animais , Antígenos CD/metabolismo , Biomarcadores/metabolismo , Biópsia , Antígeno CD24/metabolismo , Desdiferenciação Celular , Modelos Animais de Doenças , Imunofluorescência , Glicoproteínas/metabolismo , Humanos , Necrose Tubular Aguda/etiologia , Necrose Tubular Aguda/imunologia , Necrose Tubular Aguda/metabolismo , Túbulos Renais Proximais/imunologia , Túbulos Renais Proximais/metabolismo , Masculino , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Microscopia Imunoeletrônica , Mitocôndrias/ultraestrutura , Peptídeos/metabolismo , Fenótipo , Ratos , Ratos Wistar , Obstrução Ureteral/complicações , Obstrução Ureteral/patologia , Vimentina/metabolismoRESUMO
Intolerance to fava beans in subjects with glucose-6-phosphate-dehydrogenase deficiency (favism) may lead to severe hemolytic crises and decreased renal function. Renal biopsy findings exploring the molecular mechanisms of renal damage in favism have not been previously reported. We report a case of favism-associated acute kidney injury in which renal biopsy showed acute tubular necrosis and massive iron deposits in tubular cells. Interestingly, iron deposit areas were characterized by the presence of oxidative stress markers (NADPH-p22 phox and heme-oxigenase-1) and macrophages expressing the hemoglobin scavenger receptor CD163. In addition, iron deposits, NADPH-p22 phox, hemeoxigenase- 1 and CD163 positive cells were observed in some glomeruli. These results identify both glomerular and tubular involvement in favism-associated acute kidney injury and suggest novel therapeutic targets to prevent or accelerate recovery from acute kidney injury.
Assuntos
Injúria Renal Aguda/etiologia , Favismo/complicações , Glomérulos Renais/química , Túbulos Renais/química , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/metabolismo , Injúria Renal Aguda/terapia , Antígenos CD/análise , Antígenos de Diferenciação Mielomonocítica/análise , Biomarcadores/análise , Biópsia , Favismo/diagnóstico , Heme Oxigenase-1/análise , Humanos , Imuno-Histoquímica , Glomérulos Renais/patologia , Necrose Tubular Aguda/etiologia , Necrose Tubular Aguda/metabolismo , Túbulos Renais/patologia , Macrófagos/química , Masculino , Pessoa de Meia-Idade , NADPH Oxidases/análise , Receptores de Superfície Celular/análise , Diálise Renal , Fatores de Tempo , Resultado do TratamentoRESUMO
The Ebola virus disease (EVD) is a serious illness characterized by fever, severe vomiting and diarrhea, and, in severe cases, multi-organ failure requiring mechanical ventilation and renal replacement therapy. The current outbreak has centered in West Africa and affected over 15,000 individuals. EVD is transmitted by direct contact with blood or other infectious bodily fluid, and as such, numerous heath care workers caring for patients with EVD have become infected. During the current outbreak, a number of patients have received advanced supportive care for EVD in Europe and North America and therefore survived. Now, many hospitals in Europe and North America are planning to accept care for patients with EVD. In this review, we discussed the key issues related to the planning and delivery of advanced supportive care in patients with EVD with a focus on the factors necessary to provide renal replacement therapy (RRT). Since success in the treatment of patients with EVD rests on both patient outcome and prevention of transmission of disease to health care workers, we extensively discussed the modes of Ebola virus transmission and recommended protocols to protect health care workers. Experience now indicates that with appropriate planning and protocols, it is possible to successfully treat EVD patients with advanced supportive care (mechanical ventilation and RRT) while avoiding transmission to health care providers. Video Journal Club "Cappuccino with Claudio Ronco" at http://www.karger.com/?doi=371530.
Assuntos
Injúria Renal Aguda/terapia , Contenção de Riscos Biológicos/métodos , Cuidados Críticos/métodos , Doença pelo Vírus Ebola/complicações , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Terapia de Substituição Renal/métodos , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/etiologia , África/epidemiologia , Anticoagulantes/administração & dosagem , Anticoagulantes/efeitos adversos , Líquidos Corporais/virologia , Contenção de Riscos Biológicos/instrumentação , Contraindicações , Atenção à Saúde , Países Desenvolvidos , Diagnóstico Diferencial , Surtos de Doenças/prevenção & controle , Ebolavirus/isolamento & purificação , Ebolavirus/patogenicidade , Contaminação de Equipamentos , Doença pelo Vírus Ebola/prevenção & controle , Doença pelo Vírus Ebola/terapia , Doença pelo Vírus Ebola/transmissão , Humanos , Necrose Tubular Aguda/etiologia , Programas de Rastreamento , Equipe de Assistência ao Paciente/ética , Isolamento de Pacientes/instrumentação , Isolamento de Pacientes/métodos , Guias de Prática Clínica como Assunto , Terapia de Substituição Renal/instrumentação , Respiração Artificial , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Viagem , Desequilíbrio Hidroeletrolítico/etiologia , Desequilíbrio Hidroeletrolítico/terapiaRESUMO
Mannitol has been administered during partial nephrectomy as a renal protective agent for ischemic damage. However, we do not have any high-level clinical evidence of its effectiveness. The aim of the present study was to evaluate the effect of mannitol during open partial nephrectomy by comparing the postoperative renal function of patients who received it and those who did not. We retrospectively reviewed the records of 55 patients who underwent open partial nephrectomy for renal cancer in a solitary kidney from January 1990 to December 2012, and who were followed up postoperatively for at least 6 months. Of the 55 patients, mannitol was given to 20 patients (group M+) and not to the other 35 patients (group M-). We compared not only the postoperative estimated glomerular filtration rate, but also its decrease rate and the incidence of acute kidney injury requiring dialysis in the two groups. There were no significant differences in perioperative patient characteristics between the two groups. Mannitol made no significant difference in both the postoperative estimated glomerular filtration rate and its decrease rate at any point within 6 months of the postoperative period. The incidence of acute kidney injury requiring dialysis was one (5.0%) in group M+ and two (5.7%) in group M-. These findings suggest that there might be no advantage from the administration of mannitol during open partial nephrectomy.