Hypercoagulability, renal vein thrombosis, and other thrombotic complications of nephrotic syndrome

Protective effects of antithrombin on puromycin aminonucleoside nephrosis in rats

We investigated the effects of antithrombin, a plasma inhibitor of coagulation factors, in rats with puromycin aminonucleoside-induced nephrosis, which is an experimental model of human nephrotic syndrome. Antithrombin (50 or 500 IU/kg/i.v.) was administered to rats once a day for 10 days immediately after the injection of puromycin aminonucleoside (50 mg/kg/i.v.). Treatment with antithrombin attenuated the puromycin aminonucleoside-induced hematological abnormalities. Puromycin aminonucleoside-induced renal dysfunction and hyperlipidemia were also suppressed. Histopathological examination revealed severe renal damage such as proteinaceous casts in tubuli and tubular expansion in the kidney of control rats, while an improvement of the damage was seen in antithrombin-treated rats. In addition, antithrombin treatment markedly suppressed puromycin aminonucleoside-induced apoptosis of renal tubular epithelial cells. Furthermore, puromycin aminonucleoside-induced increases in renal cytokine content were also decreased. These findings suggest that thrombin plays an important role in the pathogenesis of puromycin aminonucleoside-induced nephrotic syndrome. Treatment with antithrombin may be clinically effective in patients with nephrotic syndrome.

[Risk of venous thromboembolism in acute medical illnesses. Part 2: Situations at risk in ambulatory, hospital and internal medicine settings]

PURPOSE

The increased risk of thromboembolism in acute medical illnesses (AMI) is difficult to assess because of the diversity of medical conditions. The first part of this review of the literature was dedicated to methods of risk analysis based on our current pathophysiological knowledge. This second part describes more specifically the risk of venous thrombosis linked to AMI in hospital, ambulatory and internal medicine settings.

CURRENT KNOWLEDGE AND KEY POINTS

The incidence of venous thromboembolism is higher in hospital than in ambulatory setting, albeit the latter remains significant. Stroke and affections leading to intensive care management represent conditions at great risk. Several mechanisms leading to a prothrombotic state have been identified, explaining the increased risk observed during relapses of pathologies specifically treated in internal medicine such as lupus erythematosus, Wegener granulomatosis, inflammatory bowel diseases and Behcet's disease.

FUTURE PROSPECTS AND PROJECTS

Next to the pathophysiological understanding of venous thrombosis, the assessment of the specific thrombogenic burden of an AMI is an additive tool to screen medical patients at high risk. This systematic review of the literature shows uncertainties towards some risk factors as bedrest or acute inflammatory response. Taking into account the methodological difficulties inherent to prospective and epidemiological studies, a meta-analysis focusing on these factors would be useful to refine prevention guidelines for venous thromboembolism in medical setting.

Venous thromboembolism in patients hospitalized with nephrotic syndrome

PURPOSE

Whether pulmonary embolism in patients with the nephrotic syndrome is caused by deep venous thrombosis or renal vein thrombosis is controversial. To determine which is the likely cause of pulmonary embolism in patients with the nephrotic syndrome, we investigated data from the National Hospital Discharge Survey.

METHODS

The number of patients discharged from nonfederal short-stay hospitals in the United States with a diagnostic code of nephrotic syndrome, deep venous thrombosis, renal vein thrombosis, and pulmonary embolism was obtained using ICD-9-M (International Classification of Diseases, Ninth Revision, Clinical Modification) codes.

RESULTS

From 1979 to 2005, 925,000 patients were discharged from hospitals with the nephrotic syndrome and 898,253,000 patients did not have the nephrotic syndrome. With the nephrotic syndrome, 5000 (0.5%) had pulmonary embolism, 14,000 (1.5%) had deep venous thrombosis, and fewer than 5000 had renal vein thrombosis. The relative risk of pulmonary embolism comparing patients with the nephrotic syndrome to those who did not have it was 1.39, and the relative risk of deep venous thrombosis was 1.72. Among patients aged 18-39 years, the relative risk of deep venous thrombosis was 6.81. From 1991-2005, after venous ultrasound was generally available, the relative risk of deep venous thrombosis (all ages) was 1.77.

CONCLUSION

The nephrotic syndrome is a risk factor for venous thromboembolism. This is strikingly apparent in young adults. Renal vein thrombosis was uncommon. Therefore, pulmonary embolism, if it occurs, is likely to be due to deep venous thrombosis and not renal vein thrombosis.

Arterial thrombosis associated with factor V Leiden and methylenetetrahydrofolate reductase C677T mutation in childhood membranous glomerulonephritis

Acquired abnormalities of coagulation and fibrinolysis in nephrotic syndrome have been implicated in the pathogenesis of deep-vein and arterial thrombosis. A mutation in the factor V and methylenetetrahydrofolate reductase (MTHFR) gene, the commonest inherited risk factor for venous thrombosis, may contribute to the risk of both arterial and deep-vein thrombosis in patients with nephrotic syndrome. Here, we report on an arterial thrombosis in a young girl with idiopathic membranous glomerulonephritis associated with heterozygous factor V Leiden and homozygous MTHFR C677T mutation. We postulate that screening for factors such as factor V Leiden and MTHFR C677T mutation may be beneficial to patients associated with thromboembolism and idiopathic nephrotic syndrome.

High absolute risks and predictors of venous and arterial thromboembolic events in patients with nephrotic syndrome: results from a large retrospective cohort study

BACKGROUND

No data are available on the absolute risk of either venous thromboembolism (VTE) or arterial thromboembolism (ATE) in patients with nephrotic syndrome. Reported risks are based on multiple case reports and small studies with mostly short-term follow-up. We assessed the absolute risk of VTE and ATE in a large, single-center, retrospective cohort study and attempted to identify predictive factors in these patients.

METHODS AND RESULTS

A total of 298 consecutive patients with nephrotic syndrome (59% men; mean age, 42+/-18 years) were enrolled. Mean follow-up was 10+/-9 years. Nephrotic syndrome was defined by proteinuria > or =3.5 g/d, and patients were classified according to underlying histological lesions accounting for nephrotic syndrome. Objectively verified symptomatic thromboembolic events were the primary study outcome. Annual incidences of VTE and ATE were 1.02% (95% confidence interval, 0.68 to 1.46) and 1.48% (95% confidence interval, 1.07 to 1.99), respectively. Over the first 6 months of follow-up, these rates were 9.85% and 5.52%, respectively. Proteinuria and serum albumin levels tended to be related to VTE; however, only the predictive value of the ratio of proteinuria to serum albumin was significant (hazard ratio, 5.6; 95% confidence interval, 1.2 to 26.2; P=0.03). In contrast, neither the degree of proteinuria nor serum albumin levels were related to ATE. Sex, age, hypertension, diabetes, smoking, prior ATE, and estimated glomerular filtration rate predicted ATE (P< or =0.02).

CONCLUSIONS

This study verifies high absolute risks of symptomatic VTE and ATE that were remarkably elevated within the first 6 months. Whereas the ratio of proteinuria to serum albumin predicted VTE, estimated glomerular filtration rate and multiple classic risk factors for atherosclerosis were predictors of ATE.

Fatal diffuse pulmonary arterial thrombosis as a complication of nephrotic syndrome

A 21-year-old man was admitted to our hospital because of leg edema. Because laboratory findings revealed massive proteinuria and hypoproteinemia, he was diagnosed as having nephritic syndrome caused by minimal change disease. He was given a continuous heparin infusion and intravenous steroid therapy, at a prednisolone dose of 1 mg/kg per day, and his condition gradually improved. Five months after discharge, the patient's proteinuria relapsed. He was readmitted to our hospital and we restarted anticoagulant treatment with intravenous heparin and 60 mg prednisolone. On the third hospital day, he complained of chest pain with sudden onset and dyspnea. He quickly developed shock and died. The findings of an autopsy confirmed the presence of diffuse fibrin thrombi in bilateral pulmonary arteries, and we diagnosed the cause of death as diffuse pulmonary artery thrombosis. A coagulation test for activated partial thromboplastin time (aPTT) had already shown that aPTT was prolonged before the initiation of treatment. There may have been a deficit of antithrombin III (ATIII) - a cofactor of heparin - because of the proteinuria; thus, the continuous heparin treatment might not have been effective for the prevention of thrombosis. Alternatives to heparin treatment that do not suppress AT III, such as nafamostat mesilate or argatroban, which do not require the presence of AT III for their anticoagulant action, should be considered in cases similar to the that in the patient reported here. In patients with nephrotic syndrome who exhibit altered coagulation test results, the choice of anticoagulation therapy for treatment of the hypercoagulabilty status associated with nephrotic syndrome should be carefully considered.

Acute Flank Pain Secondary to Urolithiasis: Radiologic Evaluation and Alternate Diagnoses

This article discusses the radiologic management of the patient who has acute flank pain. It describes the evolution of radiologic imaging in patients who present with acute symptoms caused by suspected urolithiasis, the advantages of unenhanced helical CT and the limitations of abdominal radiography, intravenous urography, and ultrasonography in this setting, and the alternative diagnoses encountered within the urinary tract, abdomen, and pelvis.

Inferior vena cava filter as a preventive device for recurrent pulmonary embolism in a patient with nephrotic syndrome

OBJECTIVE

This study describes a patient with nephrotic syndrome who experienced recurrent pulmonary emboli as renal disease relapsed frequently.

CLINICAL PRESENTATION

A 30-year-old male, who was diagnosed as having nephrotic syndrome at 12, presented with general edema, ascites and hypoalbuminemia. Although the patient responded well to steroid therapy, a common cold frequently caused flare-up of nephrotic syndrome. Histopathological examination of renal tissue revealed minimal disease change. At 17, the patient had a first pulmonary embolism attack with concurrent upper respiratory tract infection. Full-blown manifestations of nephrotic syndrome with low antithrombin III levels were identified at that time. Anticoagulant therapy was administered to treat the pulmonary embolism. Since the first attack, several episodes of pulmonary emboli occurred, which, combined with kidney disease, triggered refractory nephrotic syndrome. The nephrotic syndrome did not remit, and a secondary renal biopsy identified glomerular pathological changes similar to previous biopsy results. To prevent recurrent pulmonary emboli, a Greenfield inferior vena cava filter was implanted in April 2002. No further pulmonary embolism events occurred after interventional filter deployment.

CONCLUSION

The results of this study suggest that inferior vena cava filter implantation can be effective for preventing recurrent pulmonary embolism complicating refractory nephrotic syndrome.

Low protein Z levels in children with nephrotic syndrome

Acquired deficiency of anticoagulant proteins, due to loss in the urine, has been proposed as one of the major thrombogenic alterations in nephrotic syndrome (NS). Protein Z (PZ) is a single-chain vitamin K-dependent glycoprotein. Low PZ levels are reported to be a risk factor for thrombosis. The aim of this study was to investigate protein Z and other natural anticoagulant levels in children with NS. Thirty children aged between 1.5 and 12 years with NS (Groups I and II) and 19 age-and-sex-matched healthy controls (Group III) were enrolled into the study. Patients were divided into two groups: Group I (proteinuria >40 mg/m2/hr) and Group II (patients in remission). Plasma PZ levels in Group I were significantly lower than Group II (p=0.009) and group III (p=0.018). Plasma levels of AT III for Group I were significantly lower than for Groups II and III (p=0.009, p=0.005, respectively). Protein C levels in Group I were higher than in Group II and Group III (p=0.002, p=0.000, respectively). Protein Z levels positively correlated with serum total protein and albumin levels (p=0.003, p=0.003, respectively) and negatively with the degree of proteinuria (p=0.000). Protein Z levels were positively correlated with AT III (r=0.037, p=0.04). Along with the other coagulation abnormalities, decreased protein Z may contribute to increased risk of thromboembolic complications in children with NS. The negative correlation between proteinuria and PZ level suggests the possibility of renal PZ loss. Further studies are needed to investigate the mechanism and role of decreased PZ in NS.

Endovascular treatment of obliterative hepatocavopathy with inferior vena cava occlusion and renal vein thrombosis

We describe the endovascular treatment of an occlusion of the inferior vena cava (IVC) due to obliterative hepatocavopathy with renal and iliac vein thrombosis. A 34-year-old man with nephrotic syndrome and hepatic dysfunction presented to the hospital after a 3-month history of lower extremity swelling with an acute deterioration in his condition. Magnetic resonance venography diagnosed a massive IVC occlusion with thrombosis of the entire IVC, iliac veins, and renal vein. He was treated with thrombolysis, and a chronic occlusion of the infrahepatic IVC was discovered. After venous stenting of the IVC and iliac veins, he dramatically improved. After 24 months, he remains symptom-free with a patent IVC and iliac veins.

Thromboembolic complications in the nephrotic syndrome: Pathophysiology and clinical management

Patients with the nephrotic syndrome are at increased risk of developing venous and arterial thromboembolism, the most common of which is renal vein thrombosis. There are several unanswered or controversial issues relating to the nephrotic syndrome and thromboembolism, which include the mechanism of thromboembolism, and optimal diagnostic and anticoagulant management strategies. This review will discuss several of these issues: the epidemiology and clinical spectrum of thromboembolic disease occurring in patients with the nephrotic syndrome; the pathophysiology of the hypercoagulable state associated with the nephrotic syndrome; the diagnosis of renal vein thrombosis in the nephrotic syndrome; and the evidence for prophylactic and therapeutic anticoagulation strategies in such patients.

Low-molecular-weight heparin successfully treating a nephrotic patient complicated by renal and ovarian vein thrombosis and pulmonary embolism

Thromboembolic complications, frequently associated with idiopathic membranous glomerulonephritis, are frequent and serious problems associated with nephrotic syndrome. However, ovarian vein thrombosis associated with nephrotic syndrome has never been reported. This study describes the case of a 35-year-old woman with idiopathic membranous glomerulonephritis who developed left renal vein thrombosis with ovarian vein thrombosis and pulmonary embolism. The thromboembolic complications were successfully treated with low-molecular-weight heparin. Low-molecular-weight heparin thus appears safe and effective for treating thromboembolism in nephrotic patients.

Is there a link between CD146, a novel adhesion molecule and other markers of endothelial dysfunction in nephrotic syndrome and continuous ambulatory peritoneal dialysis?

BACKGROUND

CD146 is a novel cell adhesion molecule localized at the endothelial junction. Its increased plasma levels in chronic renal failure are linked to endothelial dysfunction. Endothelial dysfunction and hemostatic disturbances, a common feature of nephrotic syndrome (NS), mimics a state of protein loosing by peritoneal membrane in patients on chronic ambulatory peritoneal dialyses (CAPD). The aim of the study was to assess CD146 in relation to other markers of endothelial cell injury in patients with NS in comparison to patients on CAPD.

MATERIALS AND METHODS

We studied 45 CAPD patients, 43 patients with nephrotic syndrome and 25 healthy volunteers. Markers of endothelial cell injury: TFPI total, full length, truncated, von Willebrand factor, trombomodulin, P-selectin, E-selectin, ICAM, VCAM and CD146 were assessed using commercially available kits.

RESULTS

All these markers studied except selectins were significantly elevated in patients with NS and CAPD when compared to the healthy volunteers. In CAPD, VCAM, thrombomodulin and CD146 were significantly elevated over NS patients. CD146 correlated significantly with ICAM as well as total and truncated TFPI in CAPD patients. Moreover, total TFPI was positively related to VCAM. CD146 correlated with ICAM in NS, whereas in healthy volunteers CD146 correlated only with TFPI concentration.

CONCLUSIONS

Our studies indicate that in nephrotic patients, as well as in CAPD, there is an evidence of endothelial cell injury. Correlations between CD146 and adhesion molecules and TFPI might further support its use as a endothelial cell function marker.

Current status of kidney transplant: update 2003

Pediatric transplantation has seen remarkable advances over the past two decades with reduced morbidity and mortality, reduced rejection rates, and improved long-term patient and allograft survival. Infants currently have short-term patient and allograft survival rates better than any other age group; short-term allograft survival rates in CD recipients are equal to those in LD recipients. With decreased rejection, long-term allograft survival is improving dramatically. Transplantation allows for much reduced risks and improved metabolic status, growth and development, and more normal social interactions. The future of transplantation continues to be exciting, with opportunities for reduced immunosuppressive medications and their side effects, and the elusive goal of transplantation tolerance seems within reach.

Physiologic inhibitors of coagulation in patients on chronic hemodialysis

Patients on hemodialysis are at increased risk for bleeding and thromboses. The intriguing balance between these risks is more complex than once thought, as endogenous clotting factors and their regulators come into contact with bioincompatible dialyzer membranes, in the setting of an extracorporeal circuit of blood flow, in the face of the uremic state. In this review, we summarize the current data on the interaction between the physiologic inhibitors of coagulation and hemodialysis. Data sources and study selection were obtained from research and review articles related to the endogenous anticoagulation pathway published in English on MEDLINE from 1972 to 2002. While protein C activity and protein S antigen concentrations are increased, there is no change in antithrombin III levels during hemodialysis in relation to predialysis levels. Plasma protein Z, which has only recently been studied in uremic subjects, is increased as well. In addition, hemodialysis leads to elevated tissue factor plasminogen inhibitor, thrombomodulin, tissue plasminogen activator, and plasminogen activator inhibitor-1 activities. The potential functional significance of these observations is discussed. Finally, as erythropoietin is commonly prescribed to uremic patients and is recognized to be prothrombotic, an appraisal of its interaction with the naturally occurring anticoagulants is presented. It is apparent that we are only beginning to realize the complexity of the interplay between this myriad of serum factors and hemodialysis. Further research is needed to shed light on this underexplored area of hemodialysis.

Markers of endothelial cell injury and thrombin activatable fibrinolysis inhibitor in nephrotic syndrome

Thromboembolic complications are often seen in patients with nephrotic syndrome. Markers of endothelial cell injury [thrombomodulin, intracellular adhesion molecule, vascular cell adhesion molecule, thrombin activatable fibrinolysis inhibitor (TAFI), protein Z, vascular endothelial growth factor, markers of thrombin and plasmin generation] were studied in 22 patients with nephrotic syndrome. All these parameters studied, except protein Z and D-dimers, were significantly higher in patients with nephrotic syndrome, whereas protein Z was significantly lower when compared with the healthy volunteers. None of the endothelial cell markers (thrombomodulin, P-selectin, E-selectin, intracellular adhesion molecule, vascular cell adhesion molecule), thrombin and plasmin generation markers (thrombin-antithrombin complexes, prothrombin fragments 1 + 2, plasmin-antiplasmin complexes, D-dimers), protein C, protein Z, vascular endothelial growth factor, and TAFI concentration and activity were directly correlated with the level of proteinuria, albumin, cholesterol, triglycerides or creatinine, except significant positive correlations between TAFI activity and serum creatinine, E-selectin and albumin as well as negative correlations between plasmin-antiplasmin complexes and proteinuria. In these patients, there is evidence of endothelial cell injury and probably secondary activation of the coagulation cascade. Elevated circulating TAFI antigen and activity might be a new link in the pathogenesis of impaired fibrinolysis and the progression of atherosclerosis in nephrotic syndrome. Protein Z deficiency might also contribute to the enhanced risk of thromboembolic complications in nephrotic syndrome.

Management of idiopathic membranous nephropathy: evidence-based recommendations

Membranous nephropathy is a frequent cause of nephrotic syndrome in adults, and in one third of these patients, it leads to end-stage renal disease. Based on an extensive critical review of the literature, the following recommendations are offered. Oral high-dose corticosteroids are ineffective in producing either a sustained remission of nephrotic syndrome or in preserving renal function in patients with membranous nephropathy, and should not be used as the sole therapy (grade A recommendation). The use of azathioprine is not associated with any significant benefits, so its use is not justified (grade C). The alkylating agents cyclophosphamide and chlorambucil are both effective in the management of membranous nephropathy. Because of growing concern about long-term toxicity, especially with cyclophosphamide, these drugs should be reserved for patients who exhibit clinical features, such as severe or prolonged nephrosis, renal insufficiency, or hypertension, that predict a high likelihood of progression to end-stage renal disease. Chlorambucil in conjunction with oral steroids is the drug of first choice (grade A). Cyclophosphamide and oral steroids are alternatives (grade B). Cyclosporine may, in the future, become the agent of choice for membranous nephropathy. Currently, it is recommended (grade B) that cyclosporine use be considered in patients at high risk for progression in membranous nephropathy or if alkylating agents are contraindicated or ineffective.

Diagnosis and treatment of nephrotic syndrome

Prompt diagnosis is essential in the planning of effective treatment for the underlying diseases responsible for nephrotic syndrome. In this review, the typical clinical and laboratory features that facilitate diagnosis of these disorders are discussed. The distinction between systemic diseases, involving the kidney, and primary glomerular diseases is emphasised. These clinical and pathological distinctions influence prognosis, and form the basis of therapy to treat the underlying disorders. Our discussion focuses on diagnosis and specific treatment of these diseases, as well as therapy of the clinical consequences of nephrotic syndrome per se.

Cerebral venous thrombosis in patients with nephrotic syndrome--case reports

The authors describe two cases of cerebral venous thrombosis (CVT) in patients with nephrotic syndrome. The main clinical features of CVT were persistent headache, hemiparesis, and seizure, and the diagnosis was based on magnetic resonance imaging and magnetic resonance angiography. Both showed acquired deficiency of free protein S. The neurologic symptoms remained stationary in the first patient, who received no anticoagulation therapy, but resolved rapidly in the second, treated with intravenous heparin and supplemented with fresh frozen plasma. CVT should be suspected in patients with nephrotic syndrome who present with symptoms of intracranial hypertension or any focal neurologic deficit.

Simultaneous manifestation of acute myocardial infarction and nephrotic syndrome

This report describes the simultaneous manifestation of ischemic heart disease and nephrotic syndrome in a 37-year-old woman presenting with acute anterior myocardial infarction. Symptoms of nephrotic syndrome, such as facial and peripheral edema accompanied by proteinuria and hyperlipidemia, and onset of severe retrosternal pain developed within 24 h. Coronary angiography revealed a complete thrombotic occlusion of the proximal portion of the left anterior descending artery with no evidence of arteriosclerotic lesions. Histologic examination of renal biopsy, including electron microscopy, revealed evidence of minimal change glomerulonephritis. Ultrastructural studies demonstrated widespread effacement of epithelial foot processes. Elevated levels of circulating fibrinogen appeared to be an important factor for the hypercoagulable state in this patient, suggesting a causative relationship between coronary thrombosis and nephrotic syndrome.

Renal vein thrombosis caused by laparoscopic cholecystectomy

A 48-year-old woman was diagnosed with right renal vein thrombosis (RVT) 2 weeks after a laparoscopic cholecystectomy. The patient had none of the major risk factors for RVT or deep vein thrombosis. She was treated with long-term anticoagulation. Complete dissolution of the thrombi was reached 1 month after diagnosis.

Cranial sinus thrombosis and preeclampsia

Cranial sinus thrombosis (CST) is known to be associated with pregnancy and puerperium. A literature review of patients with CST showed a significant proportion of preeclamptic women. The relationship between nephrotic syndrome and hypercoagulability has been well established. We present a 23-year-old gravida III, para I woman with preeclampsia who developed CST. Proteinuria may have played an important pathogenetic role in this setting.

Acquired protein S and antithrombin III deficiency caused by nephrotic syndrome: an unusual cause of graft thrombosis

Thrombotic phenomena are well-recognized complications of nephrotic syndrome attributable to loss of intermediate-sized antithrombotic proteins in the urine, resulting in a hypercoaguable state. As such, nephrotic syndrome may be associated with a reduction in circulating antithrombin III and free protein S levels. Associated spontaneous thrombotic complications are generally venous in nature, with arterial thrombosis occurring less frequently. Hypercoagulability caused by acquired nephrotic syndrome has not generally been recognized as a cause of acute thrombosis of arterial bypass grafts. We report two patients who after having nephrotic syndrome sustained acute thrombosis of their arterial bypass grafts. Pathogenesis and management are discussed.

The primary glomerulopathies

Disorders of glomerular structure and function are encountered frequently in clinical medicine. Many arise as part of a well-defined multisystem or multi-organ disease process, while in others the clinical and laboratory manifestations are consequent to the sole or predominant involvement of glomeruli. The latter are known as the primary glomerulopathies. These disorders can evoke a variety of clinical syndromes, including acute glomerulonephritis, rapidly progressive glomerulo-nephritis, nephrotic syndrome, "symptomless" hematuria and/or proteinuria, and chronic glomerulonephritis. The identification of underlying morphology, through the application of renal biopsy techniques, can provide useful information for both prognosis and treatment. Pathogenic mechanisms involved in the primary glomerulopathies are varied, but immunologic perturbations underlie many disease entities. This article describes the clinical features, pathology, natural history, and treatment of the main categories of primary glomerulonephritis, with emphasis on recent developments and practical aspects of diagnosis and management.

Sinus Venous Thrombosis Associated with a Nephrotic Syndrome in an Eight-Year-Old Child

The nephrotic syndrome (NS) is reportedly as sociated with an increased risk of thromboembolic dis ease. We describe the case of an 8-year-old child with a steroid-responsive NS who developed a longitudinal si nus venous thrombosis. No family thrombophilic ten dency was found. To our knowledge, this is the second case published with these clinical characteristics. We sug gest that the sinus venous thrombosis was precipitated by the low levels of antithrombin III and hypoalbuminemia. Moreover, steroids probably played an etiological role. Key Words: Nephrotic syndrome—Sinus venous throm bosis—Venous thrombosis—Antithrombin III.

[Role of substitution albumin therapy in drugs, hormones, electrolytes and miscellanous substances transport]

Human serum albumin (HSA) is quantitatively the most important non specific transport protein. HSA binds a wide variety of both endogenous and exogenous ligands. Hypoalbuminaemia may lead to a decreased plasma binding capability of some compounds. Biological/pharmacological consequences depend on the ligand and the target tissue. Many experimental studies suggest that hypoalbuminaemia may influence the metabolism and toxicity of endogenous ligands (bilirubin, metallic ions, oxygen radicals) and the pharmacological effect of some drugs (among others: furosemide, phenytoin, warfarin). The relevance of such information for human surgical situations remains unclear. Clinical studies are scarce and inconclusive. There is a lack of pertinent data supporting the necessity of HSA infusions in order to maintain a minimal plasma concentration and a convenient plasma transport. However, experimental data indicate that major hypoalbuminaemia should be considered with caution.

The "Fisherman's Waders" sign in a bone scan of inferior vena cava thrombosis associated with nephrotic syndrome

This paper presents a 61-year-old male patient with nephrotic syndrome, hypercoagulability and IVC thrombosis. Increased soft tissue uptake below the level of the mid chest was seen in his bone scan. The term "Fisherman's Waders" sign is suggested for this finding, whose recognition may permit the identification of inferior vena cava obstruction in bone scans. The existence of a cavo-portal shunt was also confirmed by dynamic scintigraphy.

Haemostatic parameters in childhood nephrotic syndrome. (Is there any difference in protein C levels between steroid sensitive and resistant groups?)

Plasma protein C (PC) activity, prothrombin time (PT), partial thromboplastin time (PTT) and platelet count were studied in 23 children with nephrotic syndrome (NS) and AT III activity was determined in 15 children in the same group. All parameters were compared with those obtained in a group of 16 age matched healthy controls. Mean plasma AT III activity was significantly reduced in patients with NS (P < 0.001) correspondingly, plasma AT III levels were found to be directly correlated with serum albumin and inversely correlated with proteinuria. In contrast, mean plasma PC activity, as well as PT, PTT and platelet count were similar in the NS group when compared with the control group and in addition no remarkable difference was found in the mean plasma PC activity between the steroid sensitive and resistant NS groups. In conclusion, this study demonstrated acquired AT III deficiency and normal PC levels in childhood NS. These data suggest that although plasma AT III activity depends on the severity of NS, neither the severity of NS nor the underlying renal disease is an important factor determining the changes of PC activity in childhood NS.

Resistance to activated protein C as an underlying cause of recurrent venous thrombosis during relapsing nephrotic syndrome

A 16-year-old patient with relapsing nephrotic syndrome had three episodes of deep vein thrombosis after the age of 15 years. An autosomal inherited genetic abnormality of clotting factor V, resistance to activated protein C, was found. The clinical course showed that this resistance and the nephrotic syndrome potentiated each other as risk factors for deep vein thrombosis, and long-term anticoagulation was indicated.

Renal vein thrombosis treated with thrombolytic therapy: case report and brief review

Renal vein thrombosis (RVT) can occur as a complication of the nephrotic syndrome. We present the case of a young woman with systemic lupus erythematosus with nephrotic syndrome and bilateral RVT with extension of the thrombus into the vena cava to the level of the right atrium and multiple pulmonary emboli. She was treated acutely with streptokinase, with complete resolution of the thrombi. In general, anticoagulation is the mainstay of therapy for RVT. Review of the literature reveals that thrombolytic therapy can be used safely and appears to have been reserved for those patients with the most severe disease or the more grave prognosis. we feel that thrombolytic therapy is warranted in the presence of bilateral RVT with acute renal failure, massive clot size with high risk of acute embolic events, or recurrent pulmonary emboli, in the absence of overriding contraindications.

Arterial thrombosis in the nephrotic syndrome

Thrombosis is a frequent cause of morbidity and mortality in patients with the nephrotic syndrome. Venous thrombotic complications are well recognized but arterial complications are rare. Thrombosis is multifactorial, and has been attributed to a hypercoaguable state due to alterations in blood levels of the various factors involved in the coagulation and fibrinolytic systems, alterations in platelet function, venous stasis, haemoconcentration, increased blood viscosity and possibly the administration of steroids. Thrombosis in general and arterial thrombosis in particular is a significant and potentially serious problem in nephrotic patients. Awareness of the condition and its pathogenesis is needed. Assessment for the risk factors is required to allow appropriate prophylactic measures to be taken.

The effect of glycosylated albumin on platelet aggregation

BACKGROUND

Albumin has a role in the complicated process of platelet aggregation. Although it is known that quantitative changes in plasma albumin alter platelet aggregation, less is known about the interaction between qualitative changes in plasma albumin and platelets. One common qualitative change in plasma albumin is nonenzymatic glycosylation, which occurs during states of prolonged hyperglycemia.

METHODS

Albumin was selectively removed from normal plasma by means of an affinity column. Glycosylated albumin was added to this albumin-poor plasma, and it was used to study platelet aggregation induced by low concentrations of arachidonic acid. Platelet aggregation was determined by light transmittance.

RESULTS

As the concentration of glucose in which albumin was incubated was increased, there was progressive augmentation of platelet aggregation. At a plasma glucose of 150 mg/dL, average light transmittance was 9.4%, and at 200 mg/dL, it was 24.6%. These values were significantly different at a p value < .01. At glucose levels of 300 mg/dL and 400 mg/dL, mean light transmittance was 40.6% and 74.4%, respectively, and these values were significantly different with p values of < .01.

CONCLUSIONS

Platelet aggregation in response to a relatively low concentration of arachidonic acid is enhanced in the presence of albumin that has been incubated in a medium containing levels of glucose that are higher than would be seen in normal patients but are consistent with those seen in diabetics with less than optimal control. This augmentation of platelet aggregation is statistically significant.

Case report: acute renal vein thrombosis in patients with spinal cord injury and secondary amyloidosis

Chronic spinal cord injury, when complicated by chronic suppurative infections, has replaced chronic tuberculosis as a leading cause of secondary amyloidosis. Renal involvement with secondary amyloidosis is characterized by the presence of nephrotic range proteinuria and an increased incidence of renal vein thrombosis. Two cases of acute renal vein thrombosis associated with secondary amyloidosis in patients with spinal cord injury are presented. In both cases, a past history of extensive decubitus ulcerations and urinary tract infections preceded the development of nephrotic range proteinuria. In case 1, nonoliguric acute renal failure occurred after the development of acute bilateral renal vein thrombosis. The patient declined dialytic therapy and expired with uremia. In case 2, worsening renal function and increased proteinuria resulted after the development of acute unilateral renal vein thrombosis. These cases include the clinical and anatomic findings of acute renal vein thrombosis that occur as a complication of secondary amyloidosis. Acute renal vein thrombosis should be considered whenever an acute change in renal function or increase in proteinuria is noted in this setting.