Thromboembolic complications in the nephrotic syndrome: Pathophysiology and clinical management

Prothrombin Knockdown Protects Podocytes and Reduces Proteinuria in Glomerular Disease

Chronic kidney disease (CKD) is a leading cause of death, and its progression is driven by glomerular podocyte injury and loss, manifesting as proteinuria. Proteinuria includes urinary loss of coagulation zymogens, cofactors, and inhibitors. Importantly, both CKD and proteinuria significantly increase the risk of thromboembolic disease. Prior studies demonstrated that anticoagulants reduced proteinuria in rats and that thrombin injured cultured podocytes. Herein we aimed to directly determine the influence of circulating prothrombin on glomerular pathobiology. We hypothesized that (pro)thrombin drives podocytopathy, podocytopenia, and proteinuria. Glomerular proteinuria was induced with puromycin aminonucleoside (PAN) in Wistar rats. Circulating prothrombin was either knocked down using a rat-specific antisense oligonucleotide or elevated by serial intravenous infusions of prothrombin protein, which are previously established methods to model hypo- (LoPT) and hyper-prothrombinemia (HiPT), respectively. After 10 days (peak proteinuria in this model) plasma prothrombin levels were determined, kidneys were examined for (pro)thrombin co-localization to podocytes, histology, and electron microscopy. Podocytopathy and podocytopenia were determined and proteinuria, and plasma albumin were measured. LoPT significantly reduced prothrombin colocalization to podocytes, podocytopathy, and proteinuria with improved plasma albumin. In contrast, HiPT significantly increased podocytopathy and proteinuria. Podocytopenia was significantly reduced in LoPT vs. HiPT rats. In summary, prothrombin knockdown ameliorated PAN-induced glomerular disease whereas hyper-prothrombinemia exacerbated disease. Thus, (pro)thrombin antagonism may be a viable strategy to simultaneously provide thromboprophylaxis and prevent podocytopathy-mediated CKD progression.

Association of eGFR and Albuminuria with Venous Thromboembolism

BACKGROUND

CKD has been implicated as a risk factor of venous thromboembolism, but the evidence is limited to relatively healthy populations. The objective of this study was to discern whether parameters of kidney function and damage are associated with the occurrence of venous thromboembolism after hospitalization.

METHODS

We conducted a retrospective study including 23,899 and 11,552 adult individuals hospitalized within Geisinger Health System and New York University (NYU) Langone Health from 2004 to 2019 and 2012 to 2022, respectively. A Poisson model was used to evaluate adjusted incidence rates of venous thromboembolism according to eGFR and albuminuria categories in each cohort. Cox proportional hazards models were used to analyze associations of eGFR and urinary albumin-to-creatinine ratio (UACR) with venous thromboembolism, and hazard ratios (HRs) were meta-analyzed across cohorts.

RESULTS

Both lower eGFR and higher UACR were associated with higher risks of venous thromboembolism. In the Geisinger cohort, the incidence of venous thromboembolism after hospital discharge ranged from 10.7 (95% confidence interval [CI], 9.2 to 12.6) events per 1000 person-years in individuals in G1A1 (eGFR >90 ml/min per 1.73 m 2 and UACR <30 mg/g) to 27.7 (95% CI, 20.6 to 37.2) events per 1000 person-years in individuals with G4-5A3 (eGFR <30 ml/min per 1.73 m 2 and UACR >300 mg/g). A similar pattern was observed in the NYU cohort. Meta-analyses of the two cohorts showed that every 10 ml/min per 1.73 m 2 reduction in eGFR below 60 ml/min per 1.73 m 2 was associated with a 6% higher risk of venous thromboembolism (HR 1.06 [95% CI, 1.02 to 1.11], P = 0.01), and each two-fold higher UACR was associated with a 5% higher risk of venous thromboembolism (HR 1.05 [95% CI, 1.03 to 1.07], P < 0.001).

CONCLUSIONS

Both eGFR and UACR were independently associated with higher risk of venous thromboembolism after hospitalization. The incidence rate was higher with greater severity of CKD.

PODCAST

This article contains a podcast at https://dts.podtrac.com/redirect.mp3/www.asn-online.org/media/podcast/CJASN/2023_12_14_CJN0000000000000352.mp3.

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.

Epidemiology of antiphospholipid syndrome: macro- and microvascular manifestations

Antiphospholipid syndrome (APS) is a systemic autoimmune disease characterized by thrombotic and non-thrombotic macro- and microvascular manifestations and pregnancy complications in the setting of persistent antiphospholipid antibodies (aPL), namely anticardiolipin antibodies, anti-β2 glycoprotein-I antibodies and lupus anticoagulant. Four decades after its first description, APS prevalence and incidence are still not completely understood due to the limited number of well-designed, population-based multi-ethnic studies. Furthermore, despite decades of efforts to standardise aPL immunoassays, considerable intraassay and interlaboratory variances in aPL measures still exist. Large multicentre APS cohorts have shown a 10-year survival of ∼91% and the presence of catastrophic APS occurs in about 1% of the entire population, associated with a 50% mortality rate. Clinically, any organ can be affected in the context of large, medium or small vessel (artery and/or vein) thrombosis. Macrovascular thrombosis is the hallmark of the disease and veins are more frequently affected than arteries. Deep vein thrombosis/pulmonary embolism thromboembolic disease is the most common APS manifestation, while stroke and transient ischaemic attack are the most frequent arterial thrombosis events. Myocardial infarction can also occur and contributes to increased mortality in APS. A minority of patients present with thrombosis affecting the intraabdominal organs, including the liver, spleen, small and large bowel, and the kidneys. Microvascular thrombosis, including APS nephropathy, chronic skin ulcers and livedoid vasculopathy represent a diagnostic challenge requiring histologic confirmation. In this narrative review we summarize the available evidence on APS epidemiology, focusing on the description of the prevalence of macro- and microvascular manifestations of the disease.

Efficacy and safety of prophylactic anticoagulation in patients with primary nephrotic syndrome: a systematic review and meta-analysis

BACKGROUND AND AIMS

Nephrotic syndrome (NS) is associated with an increased incidence of venous thromboembolism (VTE), approximately 10%. We performed a systematic review to evaluate the efficacy and safety of prophylactic anticoagulation in patients with NS.

METHODS

Studies evaluating prophylactic anticoagulation in NS were identified by an electronic search of MEDLINE and EMBASE databases until December 2021. Weighted mean proportion and 95% confidence intervals (CIs) of thromboembolic and haemorrhagic events were calculated using a fixed-effects and a random-effects model. The differences in the outcomes among groups were estimated as pooled odds ratio (OR) and corresponding 95% CI. Statistical heterogeneity was evaluated using the I2 statistic.

RESULTS

Five cohort studies, for a total of 414 adult patients, were included. Only two studies had a control group. The weighted mean incidence of pulmonary embolism (PE) and deep vein thrombosis in patients who received VTE prophylaxis was 1.8% (95% CI: 0.6-3.5%; I2 : 4.4%) and 0.9% (95% CI: 0.2-2.2%; I2 : 43.4%) respectively. The weighted mean incidence of major bleeding in patients who received VTE prophylaxis was 2.3% (95% CI: 1-4.2%; I2 : 25.4%). Patients with NS that received VTE prophylaxis had a non-significant reduced risk of PE (OR: 0.63 (95% CI: 0.03-14.8; I2 : 64.4%)) and an increased risk of major bleeding (OR: 2.08 (95% CI: 0.41-10.45; I2 : 0%)) compared to patients with NS that did not receive VTE prophylaxis.

CONCLUSIONS

Our findings suggest that prophylactic anticoagulation in adult patients with primary NS may reduce the risk of VTE, even if it may be associated with a not negligible bleeding risk.

Intra-abdominal Venous Thromboses and Their Management

While a plethora of articles discuss management of deep venous thromboses in extremities, there is a relative scarcity of literature comprehensively describing intra-abdominal venous thromboses, and their management. Intra-abdominal venous thromboses include iliocaval venous obstruction (ICVO), hepatic venous thrombosis (HVT), portal venous thrombosis (PVT), renal vein thrombosis (RVT), splenic vein thrombosis (SVT), and gonadal vein thrombosis (GVT); each of which provides unique microenvironmental challenges to management. Doppler ultrasound is the first line imaging modality for diagnosis, and computed tomography and magnetic resonance imaging can help define the extent of thrombus burden and aid with interventional planning. Systemic anticoagulation remains the common medical treatment for intra-abdominal venous thrombosis, however, catheter directed thrombolysis and thrombectomy show positive outcomes in ICVO, HVT, PVT, and RVT, with transjugular intrahepatic portosystemic shunt (TIPS) creation especially beneficial in HVT and PVT. In this review article, we describe pathophysiology, clinical features, imaging findings, and current management options for intra-abdominal venous thromboses.

Thromboembolic phenomena in patients with nephrotic syndrome: pathophysiology, risk factors, prophylaxis and treatment

Thromboembolic events resulting from disturbances in the body's balance of thrombotic and antithrombotic abilities are among the most life-threatening complications of nephrotic syndrome. Certain causes of nephrotic syndrome leave the patient particularly susceptible to thromboembolism. The severity of proteinuria and degree of hypoalbuminaemia are other common predictors of risk. Timely initiation of prophylactic therapy can help prevent morbidity and mortality associated with this complication in patients with nephrotic syndrome. The duration of treatment and choice of therapeutic agent depends on several factors, including the degree of hypoalbuminaemia, risk factors for thrombosis and risk of bleeding. This article reviews current understanding of the pathophysiology and risk factors for thromboembolism associated with nephrotic syndrome, and summarises recommendations and strategies for preventing and treating thromboembolic events in patients with nephrotic syndrome.

Risk factors of worsening kidney function and mortality in patients with renal vein thrombosis: a retrospective study

BACKGROUND

The outcome of renal vein thrombosis, in particular as for the long-term impact on kidney function, is not fully known. We aimed to study the natural course and outcomes of patients with renal vein thrombosis, in a large, single-center cohort.

METHODS

A single-center retrospective cohort study including patients who were diagnosed with renal vein thrombosis between January 2006 and September 2021 was analyzed. The main outcomes analyzed were worsening kidney function, defined as a decrease in eGFR of at least 40% from baseline, and all-cause mortality.

RESULTS

Eighty-seven patients were included, 56.3% were female, median age was 57 years. Malignancy was the most common cause of renal vein thrombosis (60.9%), followed by post-surgery and trauma (16.1%) and nephrotic syndrome (12.6%). At initial presentation, 65.5% of the patients were asymptomatic; the main signs and symptoms were gross hematuria (20.7%), flank pain (18.4%), and flank tenderness (9.2%). During follow-up, 18 (21.4%) patients experienced worsening kidney function and 57 (65.5%) died. Multivariable analyses showed that the risk of worsening kidney function was higher in patients with nephrotic syndrome (hazard ratio [HR] 18.41; 95% confidence interval [CI], 1.57-216.04), body weight ≥ 60 kg (HR 4.82; 95% CI 1.43-16.32), and malignancy (HR 9.10; 95% CI 1.05-78.63). Symptomatic acute renal vein thrombosis was associated with a lower risk of worsening kidney function compared to asymptomatic or symptomatic chronic renal vein thrombosis (HR 0.12; 95% CI 0.01-0.96). Malignancy (HR 5.45; 95% CI 2.58-11.54), age ≥ 75 years (HR 3.44; 95% CI 1.49-7.93), and serum albumin < 3.0 g/dL (HR 2.88; 95% CI 1.65-5.05) were associated with an increased mortality risk.

CONCLUSION

Renal vein thrombosis is associated with a high rate of worsening kidney function and mortality. It is crucial to promptly identify patients at high risk and initiate early treatment to prevent negative outcomes.

Factors associated with thrombotic disease in dogs with renal proteinuria: A retrospective of 150 cases

BACKGROUND

Knowledge of additional risk factors for thrombotic disease (TD) among dogs with renal proteinuria is limited; these might differ for TD affecting the systemic arterial (AT), systemic venous (VT), and pulmonary circulation (PT).

HYPOTHESIS/OBJECTIVES

To compare signalment and clinicopathological data between dogs with renal proteinuria with or without TD, and between dogs with AT, VT, and PT.

ANIMALS

One hundred fifty client-owned dogs with renal proteinuria, 50 of which had TD.

METHODS

Retrospective case-controlled study. A database search (2004-2021) identified proteinuric dogs (UPC > 2) with and without TD. Clinicopathological data were obtained from the records. TD and non-TD (NTD) groups were compared by binary logistic regression, and AT, VT, and PT groups by multinomial regression. Normal data presented as mean ± SD, non-normal data presented as median [25th, 75th percentiles].

RESULTS

Cavalier King Charles Spaniels were overrepresented in the TD group (OR = 98.8, 95% CI 2.09-4671, P = .02). Compared to NTD cases, TD cases had higher concentration of neutrophils (11.06 [8.92, 16.58] × 109 /L vs 7.31 [5.63, 11.06] × 109 /L, P = .02), and lower concentration of eosinophils (0 [0, 0.21] × 109 /L vs 0.17 [0.04, 0.41] × 109 /L, P = .002) in blood, and lower serum albumin (2.45 ± 0.73 g/dL vs 2.83 ± 0.73 g/dL, P = .04). AT cases had higher serum albumin concentrations than VT cases (2.73 ± 0.48 g/dL vs 2.17 ± 0.49 g/dL, P = .03) and were older than PT cases (10.6 ± 2.6 years vs 7.0 ± 4.3 years, P = .008). VT cases were older (9.1 ± 4.2 years vs 7.0 ± 4.3 years, P = .008) and had higher serum cholesterol concentration (398 [309-692 mg/dL] vs 255 [155-402 mg/dL], P = .03) than PT cases.

CONCLUSIONS AND CLINICAL IMPORTANCE

Differences between thrombus locations could reflect differences in pathogenesis.

Comparison of the prophylactic antithrombotic effect of indobufen and warfarin in patients with nephrotic syndrome: a randomized controlled trial

PURPOSE

The risk of thromboembolic events is elevated in patients with nephrotic syndrome, and warfarin use has been associated with an increased risk of bleeding. Indobufen, a selective cyclooxygenase-1 inhibitor, is currently being evaluated for the prevention of thromboembolic events in nephrotic syndrome. This study aimed to compare the efficacy and safety of indobufen with that of warfarin in patients with nephrotic syndrome.

MATERIALS AND METHODS

This multicenter, randomized, three-arm, open-label, parallel controlled trial involved a total of 180 adult patients with nephrotic syndrome from four centers in China. Patients were randomly assigned to receive 100 mg indobufen (bid), 200 mg indobufen (bid), and 3 mg warfarin (qd) daily for 12 weeks. The primary endpoints included thromboembolic and bleeding events, while laboratory results and adverse events constituted secondary endpoints.

RESULTS

No thromboembolic events occurred in the high-/low-dose indobufen and warfarin groups. Moreover, the use of a low dose of indobufen significantly reduced the risk of minor bleeding events compared with warfarin use (2% versus 18%, p < .05). Finally, adverse events were more frequent in warfarin-treated patients.

CONCLUSIONS

This study found that indobufen therapy provided equivalent effects in preventing thromboembolic events compared with warfarin therapy, while low dose of indobufen was associated with a reduced risk of bleeding events, thus it should be recommended for the prevention of thromboembolic events in clinical practice in patients with nephrotic syndrome.

TRIAL REGISTRATION NUMBER

ChiCTR-IPR-17013428.

Acute lower extremity arterial thrombosis associated with nephrotic syndrome in adults: case series and literature review

BACKGROUND

Nephrotic syndrome (NS) is a condition associated with hypercoagulability. Thromboembolic events are a well-recognized complication of NS. Venous thrombosis is well known, while arterial thrombosis, which is more severe, occurs less frequently and is mainly reported in children in the literature. The aim of this study was to understand these rare adult cases of NS associated with acute lower extremity arterial thrombosis and draw attention to them to prevent misdiagnosis and delayed treatment.

METHODS

From January 2011 and October 2022, we conducted a retrospective study of patients with NS and arterial thrombosis. Their clinical manifestations, imaging characteristics, treatments and outcomes were analyzed and compared, and a literature review was performed.

RESULTS

Nine adults with NS and acute lower limb arterial thrombosis were described. In seven of these patients, six had fresh thrombi that preceded the NS diagnosis, while one had a history of NS for 14 years and previously underwent an emergency thrombectomy. Three of the seven patients eventually underwent above-knee amputations, and the other four underwent arterial revascularization with satisfactory recovery of lower-extremity perfusion. In addition to the seven patients mentioned above, the other two received successful anticoagulant treatment, as the thrombosis was present only in the popliteal artery.

CONCLUSION

Acute lower extremity arterial thrombosis is a rare but serious and potentially lethal complication in patients with NS, and early recognition and appropriate management are crucial for good patient outcomes.

The Effects of Malnutrition on Inpatient Outcomes in Patients With Gastroparesis: A Nationwide Analysis

Introduction Gastroparesis (GP) is a chronic debilitating gastric motility disorder defined as delayed emptying of the stomach content without mechanical obstruction. It can result in nutritional deficiencies, leading to poor overall outcomes. We assessed the impact of malnutrition on in-hospital outcomes in patients with gastroparesis. Methods Patients with a primary discharge diagnosis of GP between January 2016 and December 2019 were included in the National Inpatient Sample (NIS) database. Data on patient demographics, hospital characteristics, the Charlson Comorbidity Index (CCI), and the etiology of gastroparesis were collected. The association between malnutrition and outcomes, including mortality, deep vein thrombosis (DVT), pulmonary embolism (PE), sepsis, acute kidney injury (AKI), length of stay (LOS), and total hospitalization charges (THC), were analyzed using the multivariate regression model. Results A total of 182,580 patients with gastroparesis were included in the analysis. Patients with gastroparesis and malnutrition had a higher risk of mortality (adjusted odds ratio {aOR}, 3.29; p<0.001), sepsis (aOR, 0.43; p<0.001), DVT (aOR, 2.34; p<0.001), and PE (aOR, 2.68; p<0.001) compared to patients with gastroparesis without malnutrition. No significant difference was noted in the rates of AKI. Patients with malnutrition also had a prolonged LOS (2.96 days; p<0.001) and higher THC ($22,890; p<0.001) compared to patients without malnutrition. Conclusion Gastroparesis patients with malnutrition are at a greater risk of worse outcomes than those without malnutrition. The early identification of malnutrition in gastroparesis patients can predict morbidity and mortality and assist in risk stratification to enhance outcomes. Further studies are encouraged to identify factors associated with malnutrition in gastroparesis and the impact of interventions to prevent and treat malnutrition.

Thromboembolism in nephrotic syndrome: controversies and uncertainties

Thromboembolism is one of the most serious complications of nephrotic syndrome, including both arterial and venous thromboembolic events. Rates of thromboembolism depend on a multitude of factors, including the severity and cause of nephrotic syndrome, with primary membranous nephropathy having the highest reported rates. In relation to arterial thromboembolism, the risk can be as high as 8 times that of an age- and sex-matched population. However, extrapolating risks is challenging, with published studies not being homogeneous, several being single center and retrospective, and including different causes of primary nephrotic syndrome. Determining thromboembolic risk in nephrotic syndrome is essential to enable decision making on preventive strategies. However, lack of proven strategies to help estimate risk-benefit aspects underpins variations in clinical practice. Although the use of anticoagulation following a thrombotic event is clear, this still leaves us with a clinical dilemma as to if, and who, should receive prophylactic anticoagulation, with what agent, and for how long. In the absence of clear evidence to answer these questions, prophylactic anticoagulation strategies for nephrotic syndrome currently rely on expert consensus opinion, such as in the recently published 2021 Kidney Disease Improving Global Outcomes glomerular disease guidelines. In the mainstay, these recommendations relate to patients with membranous nephropathy. Here, we detail the current controversies still faced by clinicians around the risk of thromboembolism in nephrotic syndrome, use of prophylactic anticoagulation in nephrotic syndrome and propose ways of advancing existing knowledge and practice in this field to unravel the conundrum.

Relapse of nephrotic syndrome with unusual thromboembolic event: A case report

Key Clinical Message

Most children with nephrotic syndrome heal without any sequelae. However, rare life-threatening complications such as thromboembolism may occur in pediatric nephrotic syndrome and should be considered in those with a new-onset neurologic deficit.

Abstract

The thromboembolism (TE) as a complication of nephrotic syndrome (NS) is rare and serious, and may involve renal, cerebral, pulmonary, or peripheral venous and/or arterial thrombosis. Here, we describe a 4.5-year-old male with a history of nephrotic syndrome, who developed hemorrhagic stroke in the territory of middle cerebral artery (MCA).

Nephrotic Syndrome for the Internist

Nephrotic syndrome (NS) is a key clinical entity for the internist to recognize and understand. A wide range of infectious, metabolic, malignant, and autoimmune processes drive nephrosis, leading to a syndrome defined by proteinuria, edema, and hypoalbuminemia. NS occurs due to increased permeability to proteins at the level of the glomerulus, which allows for passage of albumin and other proteins into the urine. Proteinuria leads to a cascade of clinical complications characterized by fluid accumulation, kidney inflammation, and dysregulation of coagulation and immunity. In this article, the authors review the clinically important etiologies of NS that should inform an initial clinical evaluation.

Nephrotic syndrome and acute coronary syndrome in children, teenagers and young adults: Systematic literature review

Myocardial infarction is rare in children, teenagers and young adults (aged<20 years). The most common aetiologies identified include Kawasaki disease, familial hypercholesterolaemia, collagen vascular disease-induced coronary arteritis, substance abuse (cocaine, glue sniffing), trauma, complications of congenital heart disease surgery, genetic disorders (such as progeria), coronary artery embolism, occult malignancy and several other rare conditions. Nephrotic syndrome is a very rare cause of myocardial infarction, but it is probably underestimated. The purpose of this review was to determine the current state of knowledge on acute coronary syndrome related to nephrotic syndrome. We thus performed a comprehensive structured literature search of the Medline database for articles published between January 1st, 1969 and December 31st, 2021. Myocardial infarction in young adults can be broadly divided into two groups: cases of angiographically normal coronary arteries; and cases of coronary artery disease of varying aetiology. There are several possible mechanisms underlying the association between acute coronary syndrome and nephrotic syndrome: (1) coronary thrombosis related to hypercoagulability and/or platelet hyperactivity; (2) atherosclerosis related to hyperlipidaemia; and (3) drug treatment. All of these mechanisms must be evaluated systematically in the acute phase of disease because they evolve rapidly with the treatment of nephrotic syndrome. In this review, we propose a decision algorithm for the management of acute coronary syndrome in the context of nephrotic syndrome. The final part of the review presents the short- and medium-term therapeutic strategies available. Thromboembolism related to nephrotic syndrome is a rare non-atherosclerotic cause of acute coronary syndrome, and prospective studies are needed to evaluate a systematic approach with personalized therapeutic strategies.

Oral Anticoagulation in Patients With Advanced Chronic Kidney Disease and Atrial Fibrillation: Beyond Anticoagulation

The optimal approach to prevent stroke and systemic embolism in patients with advanced chronic kidney disease (CKD) and atrial fibrillation remains unresolved. We conducted a narrative review to explore areas of uncertainty and opportunities for future research. First, the relationship between atrial fibrillation and stroke is more complex in patients with advanced CKD than in the general population. The currently employed risk stratification tools do not adequately discriminate between patients deriving a net benefit and those suffering a net harm from oral anticoagulation. Anticoagulation initiation should probably be more restrictive than is currently advocated by official guidelines. Recent evidence reveals that the superior benefit-risk profile of non-vitamin K antagonist oral anticoagulants (NOACs) vs vitamin K antagonists (VKAs) observed in the general population and in moderate CKD can be extended to advanced CKD. The NOACs yield better protection against stroke, cause less major bleeding, are associated with less acute kidney injury and a slower decline of CKD, and are associated with a lower incidence of cardiovascular events than VKAs. The VKAs may be harmful in CKD patients, in particular in patients with a high bleeding risk and labile international normalized ratio. The better safety and efficacy of NOACs as opposed to VKAs may be particularly evident in advanced CKD as a result of better on-target anticoagulation with NOACs, harmful off-target vascular effects of VKAs, and beneficial off-target vascular effects of NOACs. The intrinsic vasculoprotective effects of NOACs are supported by animal experimental evidence as well as by findings of large clinical trials and may result in use of NOACs beyond their anticoagulant properties.

Cerebral venous thrombosis in an adult with relapsing minimal change disease

Minimal change disease (MCD) is a well-known cause of fulminant acute nephrotic syndrome (NS) and has been associated with thrombotic complications. We report the case of a 51-year-old woman with previously biopsy-proven MCD in remission who presented with headache and encephalopathy shortly after a relapse of the NS and was diagnosed with cerebral venous thrombosis (CVT) complicated by intracranial hemorrhage and midline shift. One month prior, she had been initiated on an oral contraceptive agent during remission of the NS. After initiation of systemic anticoagulation, her condition rapidly deteriorated, and she passed away before being able to undergo catheter-based venous thrombectomy. We conducted a systematic literature review and identified 33 case reports of adults with NS-associated CVT. The most common symptoms were headache (83%), nausea or vomiting (47%), and altered mental status (30%). 64% of patients presented at time of initial diagnosis of the NS and 32% during a relapse. Mean urinary protein excretion was 9.32 g/day and mean serum albumin was 1.8 g/dL. 91% of patients received systemic anticoagulation, and 19% died. The outcome in the remaining cases was favorable with only one report (5%) of residual neurological deficit. Of the available kidney biopsy results, MCD was the most common diagnosis (70%), raising the hypothesis that the fulminant acute onset of the NS might be a predisposing factor for this serious thrombotic complication. Clinicians should have a high index of suspicion for CVT in patients with the NS who present with new-onset neurological symptoms, including headache and nausea.

Nephrotic Syndrome and Statin Therapy: An Outcome Analysis

Background and Objectives: Hypercholesterolemia in patients with nephrotic syndrome (NS) may predispose to cardiovascular events and alter kidney function. We aimed to evaluate statins efficiency in NS patients under immunosuppression using four endpoints: remission rate (RR), end-stage kidney disease (ESKD), major cardiovascular events (MACE), and thrombotic complications (VTE). Materials and Methods: We retrospectively examined the outcome at 24 months after diagnosis of 154 NS patients (age 53 (39–64) years, 64% male, estimated glomerular filtration rate (eGFR) 61.9 (45.2–81.0) mL/min). During the follow-up, the lipid profile was evaluated at 6 months and at 1 and 2 years. Results: The median cholesterol level was 319 mg/dL, and 83% of the patients received statins. Patients without statins (17%) had similar age, body mass index, comorbidities, blood lipids levels, NS severity, and kidney function. The most used statin was simvastatin (41%), followed by rosuvastatin (32%) and atorvastatin (27%). Overall, 79% of the patients reached a form of remission, 5% reached ESKD, 8% suffered MACE, and 11% had VTE. The mean time to VTE was longer in the statin group (22.6 (95%CI 21.7, 23.6) versus 20.0 (95%CI 16.5, 23.5) months, p 0.02). In multivariate analysis, statin therapy was not associated with better RR, kidney survival, or fewer MACE; however, the rate of VTE was lower in patients on statins (HR 2.83 (95%CI 1.02, 7.84)). Conclusions: Statins did not improve the remission rate and did not reduce the risk of MACE or ESKD in non-diabetic nephrotic patients. However, statins seemed to reduce the risk of VTE. Further randomized controlled studies are needed to establish statins’ role in NS management.

A patient with spontaneous bilateral renal vein thrombosis but no risk factors

INTRODUCTION AND IMPORTANCE

Spontaneous bilateral renal vein thrombosis is a rare condition, especially when the patient has no risk factors.

CASE PRESENTATION

In this report, we describe a patient with bilateral renal vein thrombosis who presented with severe flank pain, renal functions remained normal, and the thrombus resolved completely with anticoagulation. There is no history of hypercoagulable condition in our patient. A one-year followup with CT angiogram revealed that the kidney was functioning normally and that the thrombus in the renal veins had completely resolved.

CLINICAL DISCUSSION

Management of an acute renal vein thrombosis depends upon whether the patient presents with acute kidney injury. In general, patients without acute kidney injury can be treated with therapeutic anticoagulation, whereas those with acute kidney injury should undergo dissolution or removal of the thrombus with thrombolytic therapy with or without thrombectomy.

CONCLUSION

Diagnosis of spontaneous renal vein thrombosis requires a high index of suspicion. Patient can be managed with therapeutic anticoagulation if renal function is intact. If thrombolysis and/or thrombectomy are performed on time, kidney function can be fully restored.

Exploring the Role of Antithrombin in Nephrotic Syndrome-Associated Hypercoagulopathy: A Multi-Cohort Study and Meta-Analysis

BACKGROUND

Nephrotic syndrome is associated with an acquired hypercoagulopathy that is thought to drive its predisposition for venous thromboembolism. Previous studies have suggested that urinary antithrombin (AT) loss leading to acquired AT deficiency is the primary mechanism underlying this hypercoagulopathy, but this hypothesis has not been directly tested. The objectives of this study were to test the influence of AT levels on hypercoagulopathy in nephrotic syndrome patient samples and perform meta-analyses to evaluate the likelihood of AT deficiency in patients with nephrotic syndrome.

METHODS

Samples from three independent nephrotic syndrome cohorts were analyzed. AT antigen and activity assays were performed using ELISA and amidolytic assays, respectively. Plasma thrombin generation, albumin, and urine protein-to-creatinine ratios were determined using established methods. Meta-analyses were performed by combining these new data with previously published data.

RESULTS

AT levels were not consistently related to either plasma albumin or proteinuria. AT was quantitatively related to hypercoagulopathy in adult nephrotic syndrome, whereas AT activity was inconsistently associated with hypercoagulopathy in childhood nephrotic syndrome. Notably, hypercoagulopathy did not differ between patients with normal AT levels and those with levels below the threshold used to define clinical AT deficiency (<70%). Moreover, ex vivo AT supplementation did not significantly alter hypercoagulopathy in AT-deficient plasma samples. The meta-analyses demonstrated that AT deficiency was not a uniform feature of nephrotic syndrome and was more common in children than adults.

CONCLUSIONS

These data suggest that AT deficiency plays only a limited role in the mechanisms underlying the acquired hypercoagulopathy of nephrotic syndrome. Moreover, AT deficiency was not present in all patients with nephrotic syndrome and was more likely in children than adults despite the higher risk for venous thromboembolism in adults than children.

UK prescribing practice of anticoagulants in patients with chronic kidney disease: a nephrology and haematology-based survey

A survey to gain insight into anticoagulant prescribing practice in the setting of chronic kidney disease (CKD) across the UK was disseminated via renal and haematology networks. Areas of anticoagulant use included patients with venous thromboembolism (VTE), requiring thromboprophylaxis for VTE, Atrial Fibrillation (AF) and nephrotic syndrome.An online-survey was disseminated via British Haematology Society, UK Kidney Association, and Renal Pharmacy Group over a five month period. All responses were voluntary and anonymous.Among 117 responses there were 49 nephrology doctors, 47 renal pharmacists and 20 haematology clinicians. A specialist multidisciplinary team to discuss the specific anticoagulant management of these patients was only available to 3% (4/117) respondents. Renal function estimate used for anticoagulant dosing was mainly Cockcroft-Gault for pharmacists and haematology but lab-based estimates were used by nephrology doctors. Therapeutic dose of Low Molecular Weight Heparin was mostly likely to be reduced by one-third when used for VTE treatment, with the majority of units undertaking anti-Xa monitoring in CKD stage 5 and dialysis. Direct-acting Oral Anticoagulants are being used in patients with nephrotic syndrome, those with CKD stage 5 and on dialysis for VTE and AF in the absence of license in these indications.This survey highlighted the significant differences between anticoagulant prescribing in CKD between two professional specialties and marked variation between centres in anticoagulant management strategies employed for these patients. With gaps still existing in the evidence base and answers to these not expected within the next few years, development of a best-practice guideline would be warranted to support clinicians in this field.

A young Asian woman with thrombosis in the right renal vein and inferior vena cava: A rare case report and literature review

INTRODUCTION

Renal vein thrombosis (RVT) is a rare clinical entity wherein a blood clot forms in one of the major renal veins or its tributaries. Patients with certain risk factors, such as adults with nephrotic syndrome and infants with dehydration, are susceptible to developing it.

PATIENT CONCERNS

We present a young woman with primary thrombosis in the right renal vein and inferior vena cava. Hormonal therapy and the reception of the Medigen Vaccine Biologics Corporation coronavirus disease 2019 vaccine were the suspected risk factors for developing this disease.

PRIMARY DIAGNOSIS, INTERVENTIONS, OUTCOMES

The primary thrombosis in the right renal vein and inferior vena cava was diagnosed using abdominal computed tomography (CT), and 90% of the thrombus in the right renal vein was dissolved after ultrasound-assisted catheter-directed thrombolysis followed by urokinase infusion for 1 week. Antibiotics and rivaroxaban were prescribed for 3 days and 5 months, respectively. Cryoprecipitate transfusions based on the level of fibrinogen were also prescribed. No long-term complications were noted in the clinic visits. We demonstrate the results of ultrasound-assisted catheter-directed thrombolysis using urokinase infusion for thrombosis in the right renal vein and inferior vena cava. Lastly, we review the literature discussing RVT relevant to this case.

CONCLUSION

This study reveals the successful use of the novel technique, ultrasound-assisted catheter-directed thrombolysis using urokinase infusion, for the treatment of RVT.

Free Flap Reconstruction in a Tongue Cancer Patient with Nephrotic Syndrome: A Case Report

Free flap has become crucial for reconstruction in head and neck oncology post resection since the time of its advent. It has shown a high success rate and provides a better quality of life over loco regional flaps. Literature has shown the success of free flaps does get influenced by preexisting medical conditions of the patient. Nephrotic syndrome being a hypercoagulable state doesn't find much mention in literature and its effect on free flaps has been less studied. Hence, using a free flap in such condition creates a decision making dilemma. Here we present a case report to show the feasibility of such flaps in nephrotic syndrome patients under structured environment successfully.

Nephrotic Syndrome – Different Risk of Venous Thromboembolism with Different Approaches to Justify Prophylactic Anticoagulation

All of the circumstances influencing any of the elements of Virchow’s Triad can increase the risk of venous thromboembolism. Assessing prothrombotic factors can sometimes be difficult. One of the examples of such a condition is nephrotic syndrome. In this condition at least two elements of Virchow’s triad are affected: physiological blood composition and the venous blood flow which is slowed down by the edema. Except for the cases mentioned in KDIGO (Kidney Disease: Improving Global Outcomes), the use of anticoagulant drugs in the prophylaxis of VTE (Venous Thromboembolism) in nephrotic syndrome seems unclear. Nevertheless, due to the increased risk of VTE, it is worth implementing mechanical anticoagulant prophylaxis, which can also improve the quality of life of patients by reducing swelling. The article analyzes the current knowledge on the field and gives some proposals with low bleeding risk.

Safety and effectiveness of direct oral anticoagulants in patients with nephrotic syndrome: a report of 21 cases

Background

Nephrotic syndrome (NS) is associated with increased risk of thromboembolic events (TE) adding to the morbidity and mortality. International guidelines recommend prophylactic anticoagulation in patients with NS and high risk of TE, but no studies have identified the optimal type of anticoagulation in NS. We aimed to assess the effectiveness and safety of direct oral anticoagulant (DOAC) by analyzing the thromboembolic and bleeding events in NS patients prescribed DOAC as primary prophylaxis to prevent TE or as treatment for TE occurring in relation to NS.

Methods

We performed a single-center, retrospective study including patients with NS, a plasma albumin less than 25 g/L and prophylactic anticoagulation treatment with DOAC at the Department of Renal Medicine at Aarhus University Hospital, Denmark from July 2016 to June 2021. Patients treated with DOAC as thromboprophylaxis for other indications than NS were excluded. Baseline characteristics and outcomes, including TE, bleeding and other adverse effects associated with DOAC were obtained from medical records.

Results

We identified 268 patients treated with DOAC of which 21 patients with NS were included in the study. Nineteen patients were prescribed DOAC as thromboprophylaxis and two patients received DOAC due to previous TE, which was considered associated with the NS. The type of DOAC prescribed was apixaban (n = 10) and rivaroxaban (n = 11). No patients experienced TE during DOAC treatment, while five patients had a minor bleeding episode. Patients who experienced bleeding episodes were older (median 62 vs 51 years), more often female (80%) and had been on DOAC for a longer period (204 days vs 47 days). Neither the HAS-BLED score nor GN-risk-score predicted the risk of minor bleedings in this population.

Conclusions

In this case series, no new TE and only minor bleeding complications were observed among adult NS patients treated with DOAC.

Case of metastatic epithelioid haemangioendothelioma from an unknown primary site associated with membranous nephropathy and hypercoagulable state

We report a rare case of metastatic epithelioid haemangioendothelioma from an unknown primary site presenting with axillary lymph node metastases. The patient also had a new-onset membranous glomerulonephritis and thromboembolism, which we postulate were paraneoplastic. The pathogenesis of this rare cancer, the risk of misdiagnosis and membranous glomerulonephritis as a paraneoplastic syndrome are discussed.

Evaluation of hemostasis disorders using the thrombodynamic test in patients with chronic glomerulonephritis with nephrotic syndrome

Background. Nephrotic syndrome (NS) is accompanied by a risk of thrombotic complications due to hypercoagulability. Routine laboratory tests are not sensitive enough to detect these disorders, and therefore the use of integral coagulation tests, including a new thrombodynamic test (TT) in patients with NS, is of high relevance. Aim. Using a TT to determine hemostasis disorders in patients with chronic glomerulonephritis (CGN) with NS. Materials and methods. The study included 49 patients with CGN, mean age 37 years, of which 25 (51%) women and 24 (49%) men. Of all the examined patients, 20 (40.8%) of people had NS, 29 (59.2%) had no NS. The process of clot formation was assessed by TT. Results. According to TT, 30% (6/20) of patients with NS and 13.7% (4/29) of patients without NS have hypercoagulation with changes in parameters that go beyond the reference values. In patients with NS, an increase in clot density (D), clot formation rate (V) and clot size (CS) was found, especially when albumin decreased below 25 g/l. Negative correlations were found between the levels of albumin, creatinine and clot density (D), which reflects the level of hyperfibrinogenemia, the rate of clot formation (V) and the integral index of coagulation (CS). The results indicate mainly the activation of the plasma hemostasis due to the internal coagulation pathway. However, the correlation of Tlag (delay time for the onset of clot formation after contact of blood plasma with the insert-activator) with serum cholesterol levels may also indicate activation of the extrinsic coagulation pathway. Conclusion. In CGN patients with NS, activation of the plasma hemostasis is noted, as evidenced by an increase in the rate of formation (V) and size of the clot (CS) after 30 minutes, as well as the density of the formed clot (D).

Association of D-dimer with short-term risk of venous thromboembolism in acutely ill medical patients: A systematic review and meta-analysis

BACKGROUND

D-dimer, a marker of ongoing procoagulant activity, has been widely used for the diagnosis of venous thromboembolism (VTE). The prognostic significance of D-dimer in stratifying VTE risk for acutely ill medical patients has not been well-established.

METHODS

A literature search was performed to collect studies that compared the incidence of short-term VTE between acutely ill medical patients with elevated or nonelevated D-dimer levels. The cutoff of D-dimer was 0.5 μg/mL or otherwise defined by included studies. The study endpoint was any occurrence of VTE (inclusive of deep vein thrombosis [DVT], pulmonary embolism, or VTE-related death) within 90 days of hospital presentation. A meta-analytic approach was employed to estimate the odds ratio (OR) with 95% CI by fitting random-effects models using the generic inverse variance weighted approach.

RESULTS

A total of 10 studies representing 31,119 acutely ill medical patients were included. Compared to those with nonelevated D-dimer levels, patients with elevated D-dimer had approximately threefold greater odds for short-term VTE within 90 days (OR, 3.28; 95% CI, 2.44 to 4.40; p < 0.0001). The association of elevated D-dimer with VTE composite (OR, 3.33; 95% CI, 2.20 to 5.02) and with DVT (OR, 3.26; 95% CI, 2.32 to 4.58) was comparable. The association was significant among patients who presented various acute medical illness (OR, 2.68; 95% CI, 2.01 to 3.58) and those who presented with acute stroke (OR, 3.25; 95% CI, 2.31 to 4.58).

CONCLUSION

Elevation of D-dimer was predictive of the occurrence of VTE within 90 days among acutely ill medical patients. PROSPERO Registration ID: CRD42021264555.

Association between Severe SARS-CoV-2 Infection and Severe Acute Pancreatitis in Pregnancy and Postpartum

INTRODUCTION

SARS-CoV-2 infection (COVID-19) affects the respiratory system but is not limited to it. The gastrointestinal symptoms are polymorphic, including diarrhea, vomiting, abdominal pain, and even acute pancreatitis (AP). Pregnant women are more vulnerable to SARS-CoV-2 infection and have a higher risk of severe outcomes of COVID-19.

CASE REPORT

We present a case report of a 31-year-old primigravid patient at 30 weeks of gestation, unvaccinated, with a medical history of thrombophilia, chronic nephropathy of unknown origin, hypertension, and optic neuropathy with left eye hemianopsia. She was diagnosed with moderate-to-severe COVID-19 and respiratory failure, with indication for cesarean section. Postpartum, she developed severe acute pancreatitis, complicated by peripancreatic and supradiaphragmatic abscesses. After 3 months of hospitalization and eight surgical interventions, the patient was discharged. A short mini-review of the literature is introduced.

CONCLUSION

Pregnant women with cardiovascular comorbidities are prone to severe complications of SARS-CoV-2 infection. Clinicians should be aware of the association of SARS-CoV-2 and AP in pregnant women.

Anti-PLA2R antibody measured by ELISA predicts the risk of vein thrombosis in patients with primary membranous nephropathy

Background

Primary membranous nephropathy (PMN) is associated with the highest risk for developing venous thrombosis compared with other nephrotic diseases. The aim of the study was to assess the predictive value of the pathognomonic anti-phospholipase A2 receptor (PLA2R) antibody with regard to incidence of venous thrombosis in PMN.

Methods

A total of 365 in-hospital patients diagnosed with PMN were enrolled in the study. Anti-PLA2R antibody was detected by commercial enzyme-linked immunosorbent assay. Multivariate logistic regression was used to detect the independent risk factors for venous thrombosis.

Results

Thirty-seven patients (10.14%) had venous thrombosis. Patients with venous thrombosis had higher levels of cholesterol (CHOL), low-density lipoprotein (LDL), and D-dimer than those without venous thrombosis (p < .05). Patients with venous thrombosis had significantly lower levels of albumin (23.95 ± 5.53 vs. 26.18 ± 6.59 g/L, p = .049). No significant differences were found in proteinuria, serum creatinine, estimated glomerular filtration rate, platelets, and fibrinogen between patients with and without thrombosis. Anti-PLA2R antibody levels in patients with venous thrombosis were significantly higher than in patients without it (p = .002). In the univariate logistic regression, Ln anti-PLA2R antibody (OR: 1.340; p = .004), albumin (OR: 0.945; p = .050), CHOL (OR: 1.191; p = .006), and LDL (OR: 1.271, p = .006) were associated with venous thrombosis. Ln anti-PLA2R antibody (OR = 1.269; 95%CI: 1.032–1.561), and LDL (OR = 1.213; 95%CI: 1.017–1.448) were the independent risk factors for venous thrombosis (p < .05) in multivariate analysis.

Conclusions

Anti-PLA2R antibody was the independent risk factor for venous thrombosis in PMN. Larger prospective studies were warranted to verify the results in future.

Thrombodynamics as a tool for monitoring hemostatic disorders in patients with chronic glomerulonephritis complicated by nephrotic syndrome

Nephrotic syndrome (NS) is associated with a high risk for venous and arterial thrombosis due to hypercoagulability. Integral tests designed to assess hemostasis can become an alternative for measuring hypercoagulability in patients with NS. STUDY OBJECTIVE: To assess hemostatic disorders in CGN patients complicated by NS using the thrombodynamics test. MATERIALS AND METHODS: The study included 60 adult patients with chronic glomerulonephritis (CGN), mean age 37 years, 31 (52%) women, and 29 (48%) men. Among all patients, 53 % of patients had NS, 47 % had no sign of NS. Hemostasis was assessed using the thrombodynamics test. The results were compared with biochemical parameters, which are usually associated with NS and renal dysfunction. RESULTS: According to the thrombodynamics test, CGN patients with NS demonstrated a tendency to hypercoagulability: increased rates of V (rate of clot growth), increased D (clot density), and increased CS (clot size) after 30 minutes. A positive correlation of these parameters with the serum albumin, creatinine levels, and glomerular filtration rate (GFR) indicates the influence of severe NS and renal dysfunction on the hemostasis activation in CGN patients with NS. CONCLUSION: According to the thrombodynamics test, CGN patients with NS demonstrate increased rates of clot formation, increased clot size after 30 minutes, and increased clot density due to secondary hemostasis activation. These changes positively correlate with the severity of hypoalbuminemia, hypercholesterolemia, and renal dysfunction in NS patients.

Renal Vein Thrombosis on Point-of-care Ultrasound in the Emergency Department: A Case Report

Introduction

This case report of renal vein thrombosis found on emergency bedside ultrasound illustrates the expanding role of point-of-care ultrasound (POCUS) in rapidly identifying rare renal pathologies.

Case Report

A 16-year-old female with a complex medical history presenting with right-sided abdominal pain and tenderness was found to have significant renal POCUS findings consistent with renal vein thrombosis.

Conclusion

In the medically complex patient with nonspecific chief complaints, it can be challenging to rapidly narrow a broad differential diagnosis. Point-of-care ultrasound has proven to be an extremely useful tool for this purpose. As emergency physicians become more proficient in the use of ultrasonography, it is likely that POCUS will be used with increasing frequency to identify additional pathology outside its traditional applications.

Patients with venous thromboembolism after spontaneous intracerebral hemorrhage: a review

Background

Patients with spontaneous intracerebral hemorrhage (ICH) have a higher risk of venous thromboembolism (VTE) and in-hospital VTE is independently associated with poor outcomes for this patient population.

Methods

A comprehensive literature search about patients with VTE after spontaneous ICH was conducted using databases MEDLINE and PubMed. We searched for the following terms and other related terms (in US and UK spelling) to identify relevant studies: intracerebral hemorrhage, ICH, intraparenchymal hemorrhage, IPH, venous thromboembolism, VTE, deep vein thrombosis, DVT, pulmonary embolism, and PE. The search was restricted to human subjects and limited to articles published in English. Abstracts were screened and data from potentially relevant articles was analyzed.

Results

The prophylaxis and treatment of VTE are of vital importance for patients with spontaneous ICH. Prophylaxis measures can be mainly categorized into mechanical prophylaxis and chemoprophylaxis. Treatment strategies include anticoagulation, vena cava filter, systemic thrombolytic therapy, catheter-based thrombus removal, and surgical embolectomy. We briefly summarized the state of knowledge regarding the prophylaxis measures and treatment strategies of VTE after spontaneous ICH in this review, especially on chemoprophylaxis and anticoagulation therapy. Early mechanical prophylaxis, especially with intermittent pneumatic compression, is recommended by recent guidelines for patients with spontaneous ICH. While decision-making on chemoprophylaxis and anticoagulation therapy evokes debate among clinicians, because of the concern that anticoagulants may increase the risk of recurrent ICH and hematoma expansion. Uncertainty still exists regarding optimal anticoagulants, the timing of initiation, and dosage.

Conclusion

Based on current evidence, we deem that initiating chemoprophylaxis with UFH/LMWH within 24–48 h of ICH onset could be safe; anticoagulation therapy should depend on individual clinical condition; the role of NOACs in this patient population could be promising.

Genetic variants associated with platelet count are predictive of human disease and physiological markers

Platelets play an important role in hemostasis and other aspects of vascular biology. We conducted a meta-analysis of platelet count GWAS using data on 536,974 Europeans and identified 577 independent associations. To search for mechanisms through which these variants affect platelets, we applied cis-expression quantitative trait locus, DEPICT and IPA analyses and assessed genetic sharing between platelet count and various traits using polygenic risk scoring. We found genetic sharing between platelet count and counts of other blood cells (except red blood cells), in addition to several other quantitative traits, including markers of cardiovascular, liver and kidney functions, height, and weight. Platelet count polygenic risk score was predictive of myeloproliferative neoplasms, rheumatoid arthritis, ankylosing spondylitis, hypertension, and benign prostate hyperplasia. Taken together, these results advance understanding of diverse aspects of platelet biology and how they affect biological processes in health and disease.

Evgenia Mikaelsdottir et al. report a study of variants associated with platelet count among European individuals where they identify 577 associations. They also report a genetic overlap between platelet count and human diseases, including myeloproliferative neoplasms, rheumatoid arthritis, and hypertension, as well as a genetic overlap between platelet count and various physiological markers.

Primary Nephrotic Syndrome and Risks of ESKD, Cardiovascular Events, and Death: The Kaiser Permanente Nephrotic Syndrome Study

BACKGROUND

Little population-based data exist about adults with primary nephrotic syndrome.

METHODS

To evaluate kidney, cardiovascular, and mortality outcomes in adults with primary nephrotic syndrome, we identified adults within an integrated health care delivery system (Kaiser Permanente Northern California) with nephrotic-range proteinuria or diagnosed nephrotic syndrome between 1996 and 2012. Nephrologists reviewed medical records for clinical presentation, laboratory findings, and biopsy results to confirm primary nephrotic syndrome and assigned etiology. We identified a 1:100 time-matched cohort of adults without diabetes, diagnosed nephrotic syndrome, or proteinuria as controls to compare rates of ESKD, cardiovascular outcomes, and death through 2014, using multivariable Cox regression.

RESULTS

We confirmed 907 patients with primary nephrotic syndrome (655 definite and 252 presumed patients with FSGS [40%], membranous nephropathy [40%], and minimal change disease [20%]). Mean age was 49 years; 43% were women. Adults with primary nephrotic syndrome had higher adjusted rates of ESKD (adjusted hazard ratio [aHR], 19.63; 95% confidence interval [95% CI], 12.76 to 30.20), acute coronary syndrome (aHR, 2.58; 95% CI, 1.89 to 3.52), heart failure (aHR, 3.01; 95% CI, 2.16 to 4.19), ischemic stroke (aHR, 1.80; 95% CI, 1.06 to 3.05), venous thromboembolism (aHR, 2.56; 95% CI, 1.35 to 4.85), and death (aHR, 1.34; 95% CI, 1.09 to 1.64) versus controls. Excess ESKD risk was significantly higher for FSGS and membranous nephropathy than for presumed minimal change disease. The three etiologies of primary nephrotic syndrome did not differ significantly in terms of cardiovascular outcomes and death.

CONCLUSIONS

Adults with primary nephrotic syndrome experience higher adjusted rates of ESKD, cardiovascular outcomes, and death, with significant variation by underlying etiology in the risk for developing ESKD.

A young woman presented with massive pulmonary embolism with inferior vena cava thrombus as a complication of nephrotic syndrome: a case report

Nephrotic syndrome (NS) was first described in 1827 as the presence of proteinuria of ≥ 3.5 g/24 h, hypoalbuminemia < 3.0 g/dl, peripheral edema, hyperlipidemia, lipiduria, and increased thrombotic risk. Nephrotic syndrome has an incidence of three cases per 100,000 each year in adults. Nephrotic syndrome also has serious complications due to hypercoagulable state in both various venous and arteries which could lead thromboembolic events. The pathophysiology of hypercoagulability in the nephrotic syndrome is due to an imbalance of prothrombotic and antithrombotic factors, as well as impaired thrombolytic activities.Here, we will present a 19-year-old woman who presented to the emergency department complaining of chest pain and shortness of breath for 3 days. The patient was quickly diagnosed with pulmonary embolism and inferior vena cava thrombosis as a complication of nephrotic syndrome, allowing prompt initiation of anticoagulant therapy. After 2 weeks of admission, the patient's condition resolved, her laboratory results returned to almost normal and the patient was discharged with oral prednisolone, coumadin, atorvastatin, and ramipril. We aim to determine which is the likely cause of pulmonary embolism in patients with nephrotic syndrome.

Prophylactic anticoagulants to prevent venous thromboembolism in patients with nephrotic syndrome-A retrospective observational study

Background

Nephrotic syndrome (NS) is associated with increased risk of venous thromboembolism (VTE). Guidelines suggest prophylactic anticoagulants to patients with high risk of thrombosis and low risk of bleeding, but the evidence behind this is poor. This study aims to investigate the effectiveness and risks of prophylactic anticoagulants (PAC) and investigate risk factors for VTE and bleeding in NS.

Methods

A retrospective medical records study including adults with NS, biopsy proven glomerular disease in the county of Västernorrland, Sweden. Outcomes were VTE, bleeding and death. Patients divided into PAC- and no PAC group were compared using Fisher’s exact test. Patient time was divided into serum/plasma(S/P)-albumin intervals (<20g/L and ≥20g/L) and VTE- and bleeding rates were calculated.

Results

In 95 included NS patients (PAC = 40, no PAC = 55), 7 VTE (7.4%) and 17 bleedings (18%) were found. Outcomes didn’t differ significantly between the PAC and no PAC group. Time with S/P-albumin <20g/L conferred higher rates/100 years of VTE (IRR 21.7 (95%CI 4.5–116.5)) and bleeding (IRR 5.0 (1.4–14.7)), compared to time with S/P-albumin>20g/L.

Conclusion

Duration of severe hypoalbuminemia (S/P-albumin <20g/L) in NS is a risk factor for both VTE and bleeding. There is a need for randomized controlled studies regarding the benefit of PAC in NS as well as risk factors of thrombosis and bleeding in NS.

The Association of Syndecan-1, Hypercoagulable State and Thrombosis and in Patients With Nephrotic Syndrome

The aim of this study is to investigate whether Syndecan-1 (SDC-1), an indicator of endothelial glycocalyx injury, would increase the risk of hypercoagulable state and thrombosis in patients with nephrotic syndrome (NS). The prospective study was conducted among patients undergoing renal biopsy in the Department of Nephrology in our hospital from May to September 2018. We enrolled in patients with NS as the experimental group and patients with normal serum creatinine and proteinuria less than 1 g as the control group. Patients’ characteristics including age, sex, laboratory test results and blood samples were collected for each patient. The blood samples were taken before the renal biopsy. The samples were immediately processed and frozen at −80°C for later measurement of Syndecan-1. One hundred and thirty-six patients were enrolled in the study. Patients with NS and hypercoagulability had a higher level of SDC-1 compared with control group. Patients with membranous nephropathy occupied the highest SDC-1 level (P = 0.012). Logistic regression showed that highly increased level of SDC-1 (>53.18 ng/ml) was an independent predicator for predicting hypercoagulable state. The elevated level of SDC-1 indicated that endothelial injury, combined with its role of accelerating hypercoagulable state, might be considered of vital importance in the pathophysiological progress of thrombosis formation in patients with NS.

Low serum albumin levels predict poor outcome in patients with acute ischaemic stroke or transient ischaemic attack

BACKGROUND

To examine the relationship of serum albumin with poor functional outcome and mortality in patients with acute ischaemic stroke (AIS) or transient ischaemic attack (TIA), and perform a meta-analysis to summarise the association.

METHODS

We analysed data from the Third China National Stroke Registry (CNSR-Ⅲ). Patients were divided into four groups based on serum albumin levels at admission. The outcomes included poor functional outcome (modified Rankin Scale (mRS) score of 3 to 6) and mortality at 3 months and 1 year. Multiple logistic regression models and Cox regression models were used to evaluate the association, respectively. We used a fixed-effect model to calculate the risk ratio for poor functional outcome and a random-effect model for mortality in the meta-analysis.

RESULTS

A total of 13 618 patients were enrolled. During the 3-month follow-up period, compared with 40 to 44.9 g/L group, patients in <35 g/L group had an increased risk of poor functional outcome and mortality (adjusted OR 1.37 (95% CI 1.12 to 1.67); adjusted HR 2.13 (95% CI 1.41 to 3.23)). The relationship in per 10 g/L decreased serum albumin with prognosis was consistently inversed (adjusted OR 1.17 (95% CI 1.01 to 1.35); adjusted HR 1.86 (95% CI 1.30 to 2.64)). Also, low serum albumin levels were independently correlated with clinical outcomes at 1 year. In the meta-analysis, the OR for poor functional outcome pooled 3 studies per 1 g/L decrease was 1.03 (95% CI 1.02 to 1.05), and the HR for mortality pooled 5 studies was 1.07 (95% CI 1.03 to 1.11).

CONCLUSIONS

Low serum albumin levels predict poor functional outcome and mortality in patients with AIS or TIA.

Nephrotic syndrome disease activity is proportional to its associated hypercoagulopathy

INTRODUCTION

Nephrotic syndrome (NS) is associated with an acquired hypercoagulopathy that drives its strong predilection for life-threatening thrombosis. We previously demonstrated that hypercoagulopathy is proportional to NS disease severity in animal models. Therefore, hypercoagulopathy and disease severity may inform thrombosis risk and better guide therapeutic decision making. The objective of this study was thus to establish the relationship between disease severity and hypercoagulopathy in human NS.

MATERIALS AND METHODS

Thrombin generation assays (TGA) were performed on biorepository plasma samples from a prospective longitudinal NS cohort study. TGA was also determined on a separate cohort of incident NS patients. Multivariable regression was used to build NS-hypercoagulopathy relationship models.

RESULTS

Endogenous thrombin potential (ETP) was the TGA parameter most strongly correlated with NS severity and was proportional to conventional measures of NS disease activity including proteinuria, hypercholesterolemia, and hypoalbuminemia. The overall disease activity model was well correlated with ETP (R² = 0.38). The relationship with disease activity was confirmed in the second cohort. These models further revealed that ETP is related to disease activity in a manner dependent on remission status.

CONCLUSION

Consistent with our previously reported animal model observations, we found that the combination of proteinuria, hypercholesterolemia, and hypoalbuminemia correlated with ETP-defined hypercoagulopathy. Hypercoagulopathy improved significantly with partial or complete NS remission. These data are expected to inform studies designed to stratify thrombotic risk for patients with NS.

Statins can benefit patients with primary membranous nephropathy on venous thromboembolism

Objective

The aim of this study was to investigate the role of prophylactic use of statin in venous thromboembolism (VTE) in patients with primary membranous nephropathy (PMN).

Methods

A total of 734 patients with PMN were consecutively enrolled in this retrospective study. 564 patients had received statins prescription, while 170 patients did not. Kaplan–Meier methods were used for cumulative incidence plots of thromboembolic events and Cox proportional hazards regression models were used to assess risk factors. Finally, the effects of different potency of statins were evaluated.

Results

In the cohort, 37 patients (5.0%) experienced VTE. In a univariate Cox proportional hazard model, the hazard ratio (HR) for VTE in statin users versus statin non-users was 0.5 (95% CI 0.3–0.8, p = .03). Multivariable model proportional-hazards analysis corrected for co-medications and risk factors revealed that adjusted HR was 0.4 (95% CI 0.1–0.7, p = .03). According to the type and dose, statin users were assigned into 3 groups: high-intensity group (n = 278), moderate-intensity group (n = 186), and low-intensity group (n = 49). In comparison, incidences of VTEs in the three groups were similar (2.9% vs 4.8% vs 2.0%, p = .45).

Conclusions

The prophylactic use of statins could effectively decrease the occurrence of VTE in patients with PMN, and the benefits have no difference in different potency of statins.

Th17-Immune Response in Patients With Membranous Nephropathy Is Associated With Thrombosis and Relapses

Membranous nephropathy (MN) is a rare autoimmune kidney disease. Most autoimmune diseases are associated with a pro-inflammatory Th17-immune response, but little is known about immune dysregulation in MN. In China, MN was associated with exposure to fine air particulate matter (PM_2.5) that could act as a danger signal and redirect immune response toward the Th2 or Th17 pathway. We aimed to analyze the cytokine profile of MN patients and to study the possible environmental factors involved in this immune reorientation, as well as the consequences on the prognosis of the disease. In this prospective study, 59 MN patients filled a comprehensive lifestyle questionnaire. Peripheral blood cells from MN patients were stimulated in vitro to measure the cytokines produced in supernatant. Cytokine profiles of MN patients were compared to 28 healthy donors and analyzed regarding individual PM_2.5 exposure. Compared to healthy donors, MN patients had higher serum levels of Th17 and Th2 cytokines IL-17A (62 pg/ml [IQR, 16–160] versus 31 [IQR, 13–51], P=0.035), IL-6 (66767 pg/ml [IQR, 36860–120978] versus 27979 [IQR, 18672–51499], P=0.001), and IL-4 (12 pg/ml [IQR, 0–33] versus 0 pg/ml [IQR, 0–0], P=0.0003), respectively, as well as a deficiency of Th1 and regulatory T cell cytokines IFN-γ (5320 pg/ml [IQR, 501–14325] versus 18037 [IQR, 4889–31329], P=0.0005) and IL-10 (778 pg/ml [IQR, 340–1247] versus 1102 [IQR, 737–1652], P=0.04), respectively. MN patients with high IL-17A levels lived in areas highly exposed to PM_2.5: 51 μg/m³ versus 31 μg/m³ for patients with low IL-17A levels (P=0.002) while the World Health Organization recommends an exposition below 10 μg/m³. MN patients with Th17-mediated inflammation had more venous thromboembolic events (P=0.03) and relapsed more often (P=0.0006). Rituximab treatment induced Th1 and regulatory T cell cytokines but did not impact Th17 cytokines. MN patients with Th17-mediated inflammation which appears to be related to an urban environment have worse prognosis. Alternative strategies targeting dysregulated cytokine balance could be considered for these patients at high risk of relapse.

Protein energy-wasting associated with nephrotic syndrome - the comparison of metabolic pattern in severe nephrosis to different stages of chronic kidney disease

Background

Nephrotic syndrome (NS) is associated with a hypercatabolic state expressed as an exacerbated degradation of muscle mass. However, the clinical significance of this phenomenon has not yet been investigated.

The aim of the study was to evaluate the nutritional status of patients with severe NS (defined as nephrotic range proteinuria with hypoalbuminemia ≤2.5 g/dL) and estimated glomerular filtration rate (eGFR) ≥45 mL/min/1.73 m² in comparison to patients in different stages of chronic kidney disease (CKD).

Methods

Twenty men with severe NS (NS group) and 40 men without proteinuria similar in term of serum creatinine (control group) were included into the study. A retrospective cohort of 40 men with CKD stage G4 (PreD group) and 20 haemodialysis men (HD group) were added to the analysis after matching for age, height and weight using propensity score matching. The bioimpedance spectroscopy and biochemical nutritional markers were evaluated.

Results

Nephrotic patients had a significantly lower lean tissue mass (LTM; p = 0.035) and index (a quotient of LTM over height squared, LTI; p = 0.068), with an expected deficiency of LTM by 3.2 kg, and LTI by 0.9 kg/m² when compared to the control group. A significant lean tissue deficit (defined as LTI below the lower limit of the reference range by 1.0 kg/m²) was observed in 12.5% of patients in the control group in comparison to 31.7% with advanced CKD (PreD+HD; p = 0.032) and 50% with NS (p = 0.003). NS group presented with higher phosphorus (p = 0.029), uric acid (p = 0.002) and blood urea (p = 0.049) than the control group. Blood urea was strongly negatively correlated with LTM in NS (r = − 0.64, p = 0.002). Nine nephrotic patients (45%) were identified as hypercatabolic based on severe hyperphosphatemia (> 5.0 mg/dL) and/or hyperuricemia (> 8.0 mg/dL), and were characterized by higher blood urea and lower prealbumin, as well as LTM lower by 5.6 kg than in less catabolic individuals.

Conclusions

In term of lean tissue amount, NS group was more similar to advanced CKD than to the control group. We concluded that specific metabolic pattern with elevated phosphorus, uric acid and blood urea, and lean tissue deficiency may be defined as protein-energy wasting associated with nephrotic syndrome (neph-PEW).

Podocytopathies

Podocytopathies are kidney diseases in which direct or indirect podocyte injury drives proteinuria or nephrotic syndrome. In children and young adults, genetic variants in >50 podocyte-expressed genes, syndromal non-podocyte-specific genes and phenocopies with other underlying genetic abnormalities cause podocytopathies associated with steroid-resistant nephrotic syndrome or severe proteinuria. A variety of genetic variants likely contribute to disease development. Among genes with non-Mendelian inheritance, variants in APOL1 have the largest effect size. In addition to genetic variants, environmental triggers such as immune-related, infection-related, toxic and haemodynamic factors and obesity are also important causes of podocyte injury and frequently combine to cause various degrees of proteinuria in children and adults. Typical manifestations on kidney biopsy are minimal change lesions and focal segmental glomerulosclerosis lesions. Standard treatment for primary podocytopathies manifesting with focal segmental glomerulosclerosis lesions includes glucocorticoids and other immunosuppressive drugs; individuals not responding with a resolution of proteinuria have a poor renal prognosis. Renin-angiotensin system antagonists help to control proteinuria and slow the progression of fibrosis. Symptomatic management may include the use of diuretics, statins, infection prophylaxis and anticoagulation. This Primer discusses a shift in paradigm from patient stratification based on kidney biopsy findings towards personalized management based on clinical, morphological and genetic data as well as pathophysiological understanding.

Nephrotic syndrome-associated hypercoagulopathy is alleviated by both pioglitazone and glucocorticoid which target two different nuclear receptors

BACKGROUND

Thrombosis is a potentially life-threatening nephrotic syndrome (NS) complication. We have previously demonstrated that hypercoagulopathy is proportional to NS severity in rat models and that pioglitazone (Pio) reduces proteinuria both independently and in combination with methylprednisolone (MP), a glucocorticoid (GC). However, the effect of these treatments on NS-associated hypercoagulopathy remains unknown. We thus sought to determine the ability of Pio and GC to alleviate NS-associated hypercoagulopathy.

METHODS

Puromycin aminonucleoside-induced rat NS was treated with sham, Low- or High-dose MP, Pio, or combination (Pio + Low-MP) and plasma was collected at day 11. Plasma samples were collected from children with steroid-sensitive NS (SSNS) and steroid-resistant NS (SRNS) upon presentation and after 7 weeks of GC therapy. Plasma endogenous thrombin potential (ETP), antithrombin (AT) activity, and albumin (Alb) were measured using thrombin generation, amidolytic, and colorimetric assays, respectively.

RESULTS

In a rat model of NS, both High-MP and Pio improved proteinuria and corrected hypoalbuminemia, ETP and AT activity (p < .05). Proteinuria (p = .005) and hypoalbuminemia (p < .001) were correlated with ETP. In childhood NS, while ETP was not different at presentation, GC therapy improved proteinuria, hypoalbuminemia, and ETP in children with SSNS (p < .001) but not SRNS (p = .330).

CONCLUSIONS

Both Pio and GC diminish proteinuria and significantly alleviate hypercoagulopathy. Both Pio and MP improved hypercoagulopathy in rats, and successful GC therapy (SSNS) also improved hypercoagulopathy in childhood NS. These data suggest that even a partial reduction in proteinuria may reduce NS-associated thrombotic risk.

Risk factors of venous thromboembolism in patients with nephrotic syndrome: a retrospective cohort study

BACKGROUND

Nephrotic syndrome is associated with an increased risk of venous thromboembolism (VTE). However, the risk factors of VTE in nephrotic syndrome, other than hypoalbuminemia and severe proteinuria, are not well established. Therefore we aimed to investigate the risk factors of VTE in patients with nephrotic syndrome.

METHODS

This retrospective cohort study used data from a Japanese nationwide claims database. We identified patients ≥18 years of age hospitalized with nephrotic syndrome. Through multivariable logistic regression, we determined the risk factors of VTE in patients with nephrotic syndrome during hospitalization.

RESULTS

Of the 7473 hospitalized patients with nephrotic syndrome without VTE, 221 (3.0%) developed VTE. In the VTE group, 14 (6.3%), 11 (5.0%) and 198 (89.6%) patients developed pulmonary embolism, renal vein thrombosis and deep vein thrombosis, respectively. We found that female sex {odds ratio [OR] 1.39 [95% confidence interval (CI) 1.05-1.85]}, body mass index (BMI) ≥30 [OR 2.01 (95% CI 1.35-2.99)], acute kidney injury [AKI; OR 1.67 (95% CI 1.07-2.62)], sepsis [OR 2.85 (95% CI 1.37-5.93)], lupus nephritis [OR 3.64 (95% CI 1.58-8.37)] and intravenous corticosteroids use [OR 2.40 (95% CI 1.52-3.80)] were associated with a significantly higher risk of developing VTE.

CONCLUSIONS

In patients with nephrotic syndrome, female sex, BMI ≥30, AKI, sepsis, lupus nephritis and intravenous corticosteroid use may help evaluate the risk of VTE.

[Thromboembolic complications in nephrotic syndrome]

This review devoted to the nephrotic syndrome (NS) subsequent thrombotic outcomes. The pathogenesis of hypercoagulation disorders that cause venous and arterial vascular system thrombosis are studied. Discussed procoagulant and anticoagulant mechanisms imbalance due to the anticoagulants natural urinal loss, affected by disfunction of the glomerular filter selective permeability, leading to high molecular weight liver-derived proteins (at least of the albumin size) leakage, fibrinolysis depression, excessive liver synthesis of plasma clotting cascade factors and platelet activation. Presented new data on the thrombogenesis at NS concerning the role of endothelial microparticles with high prothrombogenic activity that go from damaged glomerulus endothelial capillary cells into the systemic circulation, which can turn the local renal hypercoagulation (concomitant to the kidney immune inflammation process) into the generalized, working towards the thrombosis development. The most frequent adverse variants of arterial and venous thromboses are studied, specified their basic and general risk factors, as well as individual, varying in different patients. Indications and prophylactic anticoagulant therapy regimen and thrombosis treatment duration in patients with NS are discussed. It also stressed that the decision on time and method of anticoagulant therapy for a NS patients is still a challenge for healthcare providers.