Rescue From Permanent Kidney Injury in Acute Thrombosis of Both Renal Veins, the Inferior Vena Cava, and Both Iliofemoral Veins by Catheter-Based Thrombectomy.

CASE: A 33-year-old man with previously diagnosed lupus membranous nephropathy presented with painful swelling in both legs. Laboratory tests revealed acute kidney injury, and imaging studies by duplex ultrasound and computed tomography scan showed acute thrombosis of both renal veins, the infrahepatic inferior vena cava, and both iliofemoral venous segments. Initially, pharmacomechanical thrombolysis led to an insufficient morphological result. The therapeutic breakthrough was achieved by catheter-based mechanical thrombectomy of the infrarenal vena cava and both renal veins, which successfully cleared all affected venous segments from thrombus, paralleled by improvement of the patient's condition. However, after 1 week, the patient experienced recurrent thrombosis of the right renal vein with hemorrhagic infarction of the right kidney. After further optimization of immunomodulatory and antithrombotic therapy, a repeated catheter-based mechanical thrombectomy resulted in sustained clinical improvement and preservation of renal venous drainage and kidney function. CONCLUSION: Extensive acute thrombosis of both renal veins, the inferior vena cava, and both iliofemoral venous segments is a rare emergency potentially threatening kidney function. Immediate effective thrombus removal is essential to preserve kidney function and can be achieved by catheter-based mechanical thrombectomy embedded in a comprehensive immunomodulatory and antithrombotic therapeutic concept. CLINICAL IMPACT: This case demonstrated the efficacy of a catheter-based therapeutic approach in patients with extensive thrombosis of the venous system. A catheter-based approach must be embedded in a comprehensive medical therapeutic concept, which is essential to achieve a sustainable result.

Renal vein thrombosis in neonates: a case series of diagnosis, treatment and childhood kidney function follow-up.

BACKGROUND: Neonatal renal vein thrombosis (NRVT) is a rare condition with little data available. METHODS: We retrospectively analyzed newborns diagnosed with NRVT admitted to 3 pediatric nephrology units in Paris from 2005 to 2020. RESULTS: Twenty-seven patients were analyzed (male = 59%). The median age at diagnosis was 2.5 days (1 - 4.5). Diagnosis was suspected based on at least one of the three cardinal signs of renal vein thrombosis in 93%: flank mass (67%), hematuria (67%) and thrombocytopenia (70%). In all patients, diagnosis was confirmed by ultrasound. All patients had at least one known perinatal risk factor. A prothrombotic risk factor was found in 13 patients (48%). NRVT was unilateral in 70%, involving the left renal vein in 58%. Among 25 treated patients, 19 (76%) received low molecular weight heparin (LMWH) as initial therapy, 2 (8%) received unfractionated heparin and 4 (16%) received fibrinolysis. Median duration of treatment was 8 weeks (4 - 12). Bleeding occurred significantly more often with fibrinolysis than with LMWH/supportive therapy (3 of 4: 75% vs 0 of 4: 0%, p = 0.05). Clot resolution in patients treated with fibrinolysis did not differ significantly from those treated with LMWH/supportive therapy. After a median follow-up of 5.7 years (3 years - 9.9 years), pathological kidney features were observed in 73% of the patients (19 of 26), kidney atrophy in 18 (69%), hypertension in 2 (8%), chronic kidney disease (CKD) in 1 (4%) and proteinuria in 2 (8%). CONCLUSIONS: NRVT remains a challenging condition, which still requires further study because of its associated morbidity. A higher resolution version of the Graphical abstract is available as Supplementary information.

Renal vein thrombosis in pancreatitis: a rare vascular complication.

Extrasplanchnic venous thrombosis is a rare complication of chronic pancreatitis. Thrombosis of inferior vena cava and renal vein, in particular, is extremely rare. We present our recent experience of managing two patients of chronic pancreatitis who presented with renal vein thrombosis. We also highlight the treatment dilemmas facing a clinician managing patients with this atypical and rare vascular complication.

Endovascular Thrombectomy and Lysis for Acute Renal Vein Thrombosis: Indications, Technical Aspects, Outcome, and Disease Etiology.

PURPOSE: To report a rare case of acute renal vein thrombosis (RVT) that was treated with endovascular thrombectomy and lysis, and discuss potential etiology and indications for catheter-directed management. CASE REPORT: A 21-year-old female athlete presented with sudden pain in her left flank and vomiting. A 3-phase computed tomography (CT) angiogram identified total occlusion of the left renal vein with no excretion from the swollen tender left kidney. Catheter-directed thrombolysis and thrombectomy were initiated 24 hours after onset of symptoms. Complete resolution of the RVT with normalized renal function was achieved. Post-operative Doppler ultrasound scan confirmed normal renal resistance and flow in the renal vein. The patient was discharged on Apixaban and remains well at 6 months. Combined hormonal contraception via an intra-vaginal ring and raised Factor VIII activity were the only identified risk factors. CONCLUSION: Acute complete RVT with impaired kidney function is rare. Combined hormonal contraception and increased Factor VIII activity were potential risk factors. Endovascular thrombectomy and lysis restored renal perfusion and function, and can be used effectively in the management of fit patients with acutely compromised kidney function from total renal vein obstruction.

A case report of severe Fusobacterium nucleatum sepsis secondary to nephrectomy.

BACKGROUND: Fusobacterium nucleatum (F. nucleatum) is a resident anaerobic bacterium, which in rare cases may invade blood from the head and neck or the digestive tract to cause bacteremia and induce venous thrombosis. F. nucleatum is closely related to abdominal tumors, but it has not been reported in relation to renal tumors. We report herein a possible case. CASE PRESENTATION: This patient had kidney cancer with thrombosis in the right renal vein but had no sign of infection. After radical nephrectomy, thrombi formed in his left renal vein, and when removed, severe sepsis occurred. He did not respond to treatment with antibiotics and died, but the blood culture done confirmed that he had F. nucleatum bacteremia. CONCLUSION: F. nucleatum may also be associated with kidney cancer, and could cause post-operative renal vein thrombosis, and sepsis or septic shock after thrombectomy.

A multidisciplinary case report of multiple myeloma with renal and cardiac involvement: a look beyond amyloidosis.

BACKGROUND: Multiple myeloma (MM) is a malignant neoplasm associated with kidney involvement in nearly half of the patients. Cast nephropathy, monoclonal immunoglobulin deposition disease (MIDD), and light chain (AL) amyloidosis are the most common monoclonal immunoglobulin-mediated causes of renal injury. Cardiac involvement is also present in MM, characterized by restrictive cardiomyopathy generated by light chain deposit or amyloid. Thromboembolic complications such as deep vein thrombosis or pulmonary embolism are also described. CASE PRESENTATION: We present an unusual multidisciplinary case of a woman with a newly diagnosed MM associated with severe proteinuria and high natriuretic peptide. A renal and fat pad biopsy with Congo red staining were performed but amyloid deposition was not discovered. While immunofluorescence on fresh frozen unfixed tissue was not contributory, the immunofluorescence on fixed tissue and electron microscopy revealed the correct diagnosis. During subsequent investigations, two intracardiac right-sided masses and massive pulmonary embolism were also detected. CONCLUSIONS: This case highlights that multiple organ involvement in patients with MM may result from a combination of paraprotein-dependent and -independent factors. Moreover, renal diseases induced by monoclonal gammopathies are a group of complex and heterogeneous disorders. Their subtle presentation and their potential multiorgan involvement require the expertise of a multidisciplinary team able to provide the most appropriate diagnostic and therapeutic assessment.

Double trouble - management of perinephric hematoma and renal vein thrombosis post percutaneous renal biopsy.

BACKGROUND: Performing percutaneous renal biopsy procedures in lupus nephritis (LN) and nephrotic syndrome presents a unique challenge to the nephrologist because of the risk of bleeding from the procedure and the hypercoagulable state in hypoalbuminemia. The management of a patient with venous thrombosis with perinephric hematoma post renal biopsy can be difficult if occurred. CASE PRESENTATION: We are presenting a case of perinephric hematoma following percutaneous renal biopsy in a 23-year-old man with lupus nephritis, nephrotic syndrome, and lower limbs deep vein thrombosis (DVT). The patient developed persistent frank haematuria, flank pain and acute urinary retention post-procedure. We have withheld his oral warfarin three days before the procedure, and no anticoagulation was given subsequently. Initial CT Angiography (CTA) renal showing stable hematoma and no visible evidence of vascular injury. Three weeks later, the patient still has persistent frank haematuria and a repeated CTA renal revealed new bilateral renal vein thrombosis. Considering the high risk of worsening symptomatic venous thrombosis, we gave subcutaneous enoxaparin sodium and restart oral warfarin despite ongoing haematuria. The frank haematuria resolved within two days of anticoagulation with no radiological evidence of worsening of the perinephric hematoma. The follow-up ultrasonography a month later showed resolution of the hematoma and renal vein thrombosis with no adverse effect. CONCLUSION: Our experience, in this case, highlighted the importance of case selection for percutaneous renal biopsy among high-risk patients. Additionally, a prolonged frank haematuria in post-renal biopsy with nephrotic syndrome warranted a reassessment, as a clinical presentation of post-procedure perinephric hematoma and renal vein thrombosis can overlap. We also demonstrated that restarting anticoagulation earlier than four weeks in a patient with renal vein thrombosis and post-renal biopsy perinephric hematoma can be safe in the selective case.

Thrombosis of the Renal Vein and Inferior Vena Cava Associated With Placental Fetal Vascular Malperfusion in a Neonate Exposed to Methadone Maintenance Therapy In Utero.

Methadone, an opioid agonist, is the recommended treatment for pregnant women with opioid use disorder (OUD). Fetal/neonatal autopsy findings as well as placental changes in the setting of maternal OUD or methadone maintenance therapy (MMT) are not well-characterized. Here we present a case of a neonate who had exposure to MMT while in utero and died shortly after birth and was subsequently found to have multifocal calcified renal vein thrombosis, a recent inferior vena cava thrombus, and placental features of fetal vascular malperfusion at autopsy.

Acute Pulmonary Thromboembolism in a Patient with Nutcracker Syndrome and Antiphospholipid Syndrome.

Nutcracker syndrome (NCS), which is defined as compression of the left renal vein between the aorta and the superior mesenteric artery, is usually benign and self-limiting. Long-term renal venous retention increases the risk of renal vein thrombosis. However, NCS rarely develops into isolated thrombosis of the left renal vein; the reason for this process remains unknown. We describe a young man with antiphospholipid syndrome, who developed overt pulmonary thromboembolism due to an isolated thrombus in the left renal vein. Complicating antiphospholipid syndrome might trigger acute pulmonary thromboembolism (APTE) in patients with NCS. To the best of our knowledge, this is the first report of APTE arising due to isolated left renal vein thrombosis in patients with NCS.

Massive thrombosis in an infant with suspected nephrocalcinosis: case report and literature review.

INTRODUCTION: Perinatal period is characterized by an increased risk of thrombosis due to low resources and limited compensatory capacity of the coagulation system in early stages of life. CASE REPORT: We report a case of a second pregnancy female infant born at 39 weeks by caesarean section, due to pre-labor rupture of membranes, with body weight of 3,570 γ and Apgar score 10. The pregnancy was complicated by hypothyroidism, uterine myoma, urinary tract infections, and mother's appendectomy at 16 Hbd. At 3 months, the girl was admitted to our hospital due to kidney calcifications, which were incidentally found during ultrasound scan. In laboratory workup, no abnormalities in calcium and phosphate homeostasis were detected. However, in ultrasound scan, linear calcifications along pyramids were visualized in both kidneys. Due to atypical location of nephrocalcinosis, Doppler scan was performed, showing lack of visible blood flow from renal veins to inferior vena cava (IVC), with compensatory flow from renal veins to paravertebral plexuses, and IVC obliteration with a massive calcification in the hepatic section. Magnetic resonance confirmed obliteration of IVC and common iliac veins, segmental dilatation of IVC, and compensatory blood flow from kidneys and lower limbs to paravertebral plexuses. Clinical picture and formation of collateral circulation suggested intrauterine thrombosis. Congenital thrombophilia was excluded in laboratory examination. CONCLUSIONS: The differential diagnosis of calcifications in renal parenchyma (nephrocalcinosis) should include renal vein thrombosis. Massive fetal and perinatal thrombosis can be asymptomatic due to high ability to form collateral circulation at the early stage of life.

Thrombophlebitis hiding under a KILT - case report on 40 years long-term follow-up of neonatal renal vein thrombosis.

BACKGROUND: Neonatal renal vein thrombosis is a recognised cause of renal and inferior caval vein atresia (IVCA). However, the long-term impact of the condition is underrecognized with a high burden of morbidity for the patient, especially in adulthood. IVCA has been shown to be an independent risk factor for deep venous thrombosis (DVT) with a high risk of recurrence. The acronym KILT for kidney and inferior vena cava anomaly with leg thrombosis summarizes the pathological situation. CASE PRESENTATION: We present the case of a 40-year-old patient with pain in the right lower limb resulting from acute thrombophlebitis. No risk factors could be identified. His history was remarkable with two episodes of deep venous thrombosis first of the left, then the right leg 22 years earlier; at that time also, no risk factor was identified. Because of the idiopathic character of that thrombosis, the patient remained on long-term anticoagulation with phenprocoumon. The present thrombophlebitis occurred while the INR was not therapeutic in the preceding weeks. A CT with contrast showed atresia of the inferior vena cava and of the right kidney, and presence of numerous collaterals. A thorough medical history revealed a renal vein thrombosis as a neonate. Anticoagulation was intensified, and stent placement became necessary after a further 2 years. DISCUSSION AND CONCLUSIONS: KILT syndrome is a rare but underrecognized condition. Complications may arise in young adulthood only, and it is of prime importance to instruct parents of the pediatric patient of the possible consequences of renal vein thrombosis and to assure guidance from the treating physicians throughout adulthood. Diagnosis of IVCA is by CT with contrast or by MRI, and lifelong anticoagulation may be necessary. Since the KILT syndrome is widely underdiagnosed, we challenge the clinicians to keep it in mind when confronted with thrombophlebitis or thrombosis of the young, male and with no other identifiable risk factors for deep vein thrombosis.

Sequential sonographic features in neonatal renal vein thrombosis.

OBJECTIVES: Renal vein thrombosis in newborns is a rare but serious and acute disease. Clinical representations of RVT can vary from discrete symptoms to life-threatening conditions. Therefore imaging, and in particular sonography, plays an important role in the diagnosis of RVT in neonates. Gray-scale, color and spectral/power Doppler ultrasound are all used in the diagnosis of RVT. MATERIAL AND METHODS: We present retrospective sequential ultrasonic imaging of three patients (two term and one preterm infant) with findings characteristic of RVT. RESULTS: Initial ultrasound diagnostic features include: renal enlargement, echogenic medullary streaks, lack of the flow pattern characteristic of arcuate vessels and subsequently loss of corticomedullary differentiation, reduced echogenicity around pyramids and echogenic band at the extreme apex of the pyramid. Higher resistance index or less pulsatile venous flow on the affected kidney are helpful Doppler signs. CONCLUSIONS: Knowledge and identification of specific features of each phase of the evolution of RTV seems essential to prompt diagnosis. We would like to highlight the evolution of specific sonographic features in each subsequent phase of RVT.

Pathological assessment of allograft nephrectomy: An Iranian experience.

BACKGROUND: The aim of this study was to determine the pathologic causes of renal allograft failure in transplant nephrectomy specimens. MATERIALS AND METHODS: In this cross-sectional study performed in the referral transplant center of Isfahan, Iran, medical files of all patients who underwent nephrectomy in 2008-2013 were studied. Age at transplantation, sex, donor's characteristics, causes of primary renal failure, duration of allograft function, and pathologic reasons of nephrectomy were extracted. Slides of nephrectomy biopsies were evaluated. Data were analyzed using SPSS. RESULTS: Medical files of 39 individuals (male: 56.4%; mean age: 35.1 ± 16.0 years) were evaluated. The main disease of patients was hypertension (17.9%), and most cases (64.1%) were nephrectomized < 6 months posttransplantation. Renal vein thrombosis (RVT) (51.3%) and T-cell-mediated rejection (TCMR) (41.0%) were the most prevalent causes of transplanted nephrectomy. Cause of primary renal failure was correlated to nephrectomy result (P = 0.04). TCMR was the only pathologic finding in all of patients nephrectomized >2 years posttransplantation. There were 14 cases in which biopsy results showed a relationship between primary disease of patients and pathologic assessment of allograft (P = 0.04). A significant relationship between transplantation-nephrectomy interval and both the nephrectomy result and histopathologic result existed (P < 0.0001). A relationship between primary allograft biopsy appearance and further assessment of nephrectomized specimen (P < 0.001) existed as well. CONCLUSION: The most pathologic diagnoses of nephrectomy in a period of less than and more than 6 months posttransplantation were RVT and TCMR, respectively. Early obtained allograft protocol biopsy is suggested, which leads to better diagnosis of allograft failure.

Catheter-directed therapy for acute renal vein thrombosis in systemic lupus erythematosus: A case report.

We report our experience using catheter-directed thrombectomy/thrombolysis (CDT) to treat a patient with acute renal vein thrombosis (RVT) associated with systemic lupus erythematosus (SLE). A 34-year-old woman presented with persistent left flank pain, and a renal ultrasonography examination revealed an enlarged left kidney. Contrast-enhanced computed tomography confirmed the presence of acute left RVT. Because medical treatment failed to relieve her pain and the renal function was deteriorating, we attempted to salvage the occluded left renal vein using an endovascular approach. The pain was completely relieved after a CDT and an overnight urokinase infusion. A follow-up computed tomography examination revealed the complete resolution of the thrombus. The creatinine level returned to normal (1.7-0.4 mg/dL), along with contrast enhancement in the left kidney, and this suggested the preservation of renal function. To our knowledge, this is the first report utilizing CDT to treat SLE-associated RVT. When the renal function is deteriorating, CDT is worth considering for RVT if conventional medical treatment has failed. © 2016 Wiley Periodicals, Inc.

Active malignancy in patients with renal vein thrombosis: influence upon clinical course and survival.

BACKGROUND: Renal vein thrombosis (RVT) is a rare event with myriad clinical manifestations. Published experience regarding the clinical course and management of RVT in patients beyond the neonatal period is limited to case reports and small case series. METHODS: A multicenter retrospective review of consecutive admitted patients with diagnosed RVT between January 2000 and May 2015 at three different university hospitals. RESULTS: Thirty-nine patients (53.8 % men and 46.2 % women) were included. Median age was 58 years. Malignancy (n = 19, 48.7 %), nephrotic syndrome (n = 8, 20.5 %) and infection (n = 5, 12.8 %), were the most common underlying conditions. Compared to non-cancer patients, patients with active cancer tended to be significantly older (mean age 63 ± 18 vs. 37 ± 22 years, P = 0.001) and presented with non-acute symptoms (P = 0.01) and unrevealing physical findings (P = 0.02). Thrombosis extension beyond the renal vein occurred in 69.2 % of cases and was more common in cancer patients (P = 0.001). Anticoagulation therapy was administered in 71.8 % of patients leading to resolution of thrombus in most cases (30/32 patients, 94 %) during follow-up evaluation. There were six recurrent thrombotic events during a mean follow-up of 35 ± 43 months. Nine patients (28 %) died during follow-up, all of them with malignancy. CONCLUSION: Active cancer is the most common cause of RVT and should be excluded when RVT is diagnosed. Clinical course of RVT in cancer patients is more indolent and diagnosis requires high index of suspicion. Survival rates are governed by the presence of malignancy.

The role of thrombectomy and diffusion-weighted imaging with MRI in post-transplant renal vein thrombosis: a case report.

BACKGROUND: Surgical thrombectomy in the context of acute renal vein thrombosis (RVT) post-transplantation has had limited success, with considerable variation in the surgical techniques used. Unfortunately, it is usually followed by allograft nephrectomy within a few days if rapid allograft recovery does not ensue. We report a case of acute RVT in which nephrectomy was not performed despite a prolonged requirement for dialysis post-thrombectomy, but with recovery of renal function 2 weeks later. We also report the findings of serial MRI with diffusion-weighted imaging (DW-MRI) throughout the patient's recovery, which provided novel insights into allograft microvascular perfusion changes post-thrombectomy. CASE PRESENTATION: A 65-year old patient underwent living-unrelated kidney transplantation complicated by acute RVT. Surgical thrombectomy and irrigation led to a delayed, but significant, recovery of renal function. Serial non-contrast DW-MRI scanning was used to non-invasively assess microvascular renal blood flow post-operatively. Unlike standard Doppler ultrasonography, DW-MRI documented reduced microvascular perfusion initially, with gradual but incomplete recovery that mirrored the partial improvement in renal function. CONCLUSIONS: Our findings suggest that surgical thrombectomy may be more effective than previously described if followed by careful patient observation. Moreover, diffusion-weighted MRI appears to provide important insights into the pathophysiology of delayed graft function and deserves further investigation.

Renal vascular thrombosis in the newborn.

Neonatal renal vascular thrombosis is rare but has devastating sequelae. The renal vein is more commonly affected than the renal artery. Most neonates with renal vein thrombosis present with at least one of the three cardinal signs, namely, abdominal mass, macroscopic hematuria and thrombocytopenia, while unilateral renal artery thrombosis presents with transient hypertension. Contrast angiography is the gold standard for diagnosis but because of exposure to radiation and contrast agents, Doppler ultrasound scan is widely used instead. Baseline laboratory tests for platelet count, prothrombin time, activated partial thromboplastin time and fibrinogen concentration are essential before therapy is initiated. Maternal blood is tested for lupus anticoagulant and anticardiolipin antibody. Evaluation for prothrombotic disorders is warranted when thrombosis is clinically significant, recurrent or spontaneous. Management should involve a multidisciplinary team that includes neonatologists, radiologists, pediatric hematologists and nephrologists. In addition to supportive therapy, recent guidelines recommend at least prophylactic heparin therapy in the majority of cases to prevent thrombus extension. Thrombolytic therapy is reserved for bilateral thrombosis compromising kidney function. Long-term sequelae, such as kidney atrophy, systemic hypertension and chronic kidney disease, are common, and follow-up by pediatric nephrologists is recommended for monitoring of kidney function, early detection and management of hypertension and chronic kidney disease.

Thromboembolic events in patients with severe inherited fibrinogen deficiency.

Inherited afibrinogenemia and hypofibrinogenemia are rare bleeding disorders characterized by markedly reduced levels of fibrinogen in blood. Thrombotic complications in these disorders have been rarely described. We performed a multicenter retrospective study and reviewed the occurrence of thrombotic complications among patients with inherited fibrinogen deficiency. Cases were identified during a review of medical records of all patients with inherited fibrinogen deficiency followed at three different university hospitals in Israel. Nine patients were included in this study: five were afibrinogenemic and four hypofibrinogenemic. There were seven thrombotic events, mostly venous, that occurred in four out of nine patients (44 %). All thrombotic events occurred in afibrinogenemic patients. Mean age at the time of thrombosis was 45 (range 28-61) years. Thrombophilic evaluation performed was negative in all cases. At the time of thrombosis in five out of seven (71.4 %) events, fibrinogen replacement therapy was concurrently given. Therapeutic approach was different among patients ranging from supportive therapy alone, antiplatelet agents and anticoagulant therapy with the concurrent administration of fibrinogen replacement therapy. This study discloses a high rate of thrombosis in patients with afibrinogenemia. Events were both venous and arterial and may be recurrent. Management is highly problematic due to the precarious balance between bleeding and thrombotic risk in these patients. Fibrinogen replacement therapy should be cautiously used in these patients as most thrombotic events followed the administration of fibrinogen replacement therapy. Larger cohorts are warranted to better characterize the best management strategy in these paradoxical events.

Acute pyelonephritis and renal vein thrombosis: A case report and review of the literature.

A 68-year-old female presented with a week history of fever and generalized weakness. Clinical examination, blood work and urinalysis were compatible with sepsis due to acute pyelonephritis. Urine cultures were positive for Escherichia coli and blood cultures were negative. After 5 days of antibiotic therapy with cefuroxime, inflammatory parameters (CRP level and white blood cell count) remained highly elevated. Abdominal CT scan showed right kidney pyelonephritis with renal and perirenal abscess and right renal vein thrombosis. The patient improved after percutaneous drainage of the perirenal abscess and anticoagulation treatment. She was discharged on hospital day 14.

Neonatal renal vein thrombosis: role of anticoagulation and thrombolysis--an institutional review.

Neonatal renal vein thrombosis (NRVT) is a rare thromboembolic complication in the neonatal period, and sequelae from renal dysfunction can cause significant morbidity. The authors retrospectively reviewed 10 patients with NRVT treated at their institution. The majority of the cohort were male (n = 9), preterm (n = 6), and had unilateral NRVT (n = 6). Six patients received thrombolysis and/or anticoagulation, and 4 patients received supportive care only. Two of the 6 patients treated with anticoagulation who had bilateral NRVT and anuria received thrombolysis with low-dose tissue plasminogen activator. Thrombolysis was not associated with any major adverse events, and both patients had marked improvement of renal function. Eight patients subsequently developed renal atrophy (3 received anticoagulation, 2 received thrombolysis with anticoagulation, and 3 received supportive care). Anticoagulation/thrombolysis did not appear to prevent renal atrophy. The role of thrombolysis needs to be further studied and considered in the setting of bilateral NRVT and acute renal failure.