Applications of LDL-apheresis in nephrology

Efficacy of Rheocarna®, a Novel Apheresis Device, in Patients With No- or Poor-Option Chronic Limb-Threatening Ischemia

BACKGROUND

Although revascularization is first-line therapy for chronic limb-threatening ischemia (CLTI), there are no established treatments for patients in whom revascularization is not (or is a poor) option, including CLTI that has responded poorly to revascularization. This study verified the efficacy of the Rheocarna®, a novel apheresis device, for no-option CLTI or poor-response CLTI after revascularization.

METHODS AND RESULTS

This multicenter retrospective observational study analyzed 221 patients (221 limbs) with no- or poor-option CLTI (mean [±SD] age 71±10 years; males, 70.1%; diabetes, 76.5%; dialysis, 87.8%; Rutherford category 6, 26.4%) undergoing apheresis with the Rheocarna between March 2021 and March 2022. The primary endpoint was the 1-year wound-healing rate. After apheresis with the Rheocarna, C-reactive protein, fibrinogen, and low-density lipoprotein cholesterol (LDL-C) levels decreased significantly, and the ankle-brachial index (ABI) and skin perfusion pressure (SPP) increased significantly (all P<0.05). At 1 year, the wound-healing rate was 60.7%, and rates of limb salvage, freedom from reintervention, overall survival, and amputation-free survival were 83.4%, 69.2%, 70.2% and 61.3%, respectively. At baseline, non-ambulatory status, lower ejection fraction, and lower blood albumin levels were independently associated with a lower wound-healing rate.

CONCLUSIONS

Apheresis with the Rheocarna in patients with no- or poor-option CLTI reduced LDL-C and fibrinogen levels and improved ABI and SPP, achieving a 1-year wound healing rate of 60.7%. This novel approach could provide additional treatment options for conventional CLTI.

The Effectiveness of Low-Density Lipoprotein/Fibrinogen Apheresis in Promoting Wound Healing of No-Option Chronic Limb-Threatening Ischemia Foot Ulcers with Wound, Ischemia, and Foot Infection (WIfI) Wound Grade 3: A Single-Center Retrospective Analysis

Background: Chronic limb-threatening ischemia (CLTI) is a severe condition associated with high mortality and amputation rates, particularly in patients with diabetes, renal failure, or severe vascular disease. In cases where revascularization fails or is not possible, adjunctive therapies can improve the treatment outcomes. Therefore, this single-center retrospective study aimed to evaluate the effectiveness of low-density lipoprotein/fibrinogen apheresis (Rheocarna®) in promoting wound healing in patients with no-option CLTI, focusing on large wounds. Methods: We examined the data of 32 CLTI ulcers treated with Rheocarna® from 2021 to 2024. Results: The outcomes in 25 cases (78.1%) were rated as excellent or good, and the outcomes of 11 (73.3%) wound, ischemia, and foot infection (WIfI) wound-3 ulcers were excellent or good. Overall, 75% of the CLTI ulcers achieved wound healing without major amputation. Predictive factors for successful wound healing included age, baseline skin perfusion pressure, and wound grade (WIfI classification). A skin perfusion pressure threshold of 28.5 mmHg (WIfI ischemic grade 3) was a significant predictor of positive outcomes. Conclusions: Our results support the use of Rheocarna® as a viable adjunctive therapy in managing refractory large ischemic ulcers and preventing major amputations.

Minimal impact of low-density lipoprotein apheresis on vancomycin serum concentration: A case report

Low-density lipoprotein apheresis (LDL-A) is a blood purification therapy used to treat refractory ulcers in patients with arteriosclerosis obliterans. We describe a case of vancomycin treatment in a patient undergoing maintenance hemodialysis and LDL-A therapy and assess its impact on serum vancomycin concentration. The patient underwent LDL-A twice a week (Mondays and Fridays) and maintenance dialysis three times a week (Tuesdays, Thursdays, and Saturdays) for diabetic nephropathy associated with type 1 diabetes mellitus. Following the wound culture results, vancomycin was initiated with a 1.75 g administration post-dialysis. Serum vancomycin levels before and after LDL-A, measured on the subsequent day, exhibited only slight fluctuations within the intermeasurement variability range. Despite continuing vancomycin administration at the standard dose in patients undergoing hemodialysis, the serum concentration remained consistent, suggesting a minimal impact of LDL-A on vancomycin pharmacokinetics.

Clinical impact of a novel lipoprotein apheresis treatment on no-option chronic limb-threatening ischemia: Result from the REDUCTION VISCOSITY study

INTRODUCTION

Lipoprotein apheresis (LA) is a possible adjunct treatment for no-option chronic limb-threatening ischemia (CLTI). This study aimed to assess the impact of a novel LA for no-option CLTI.

METHODS

We retrospectively assessed 19 patients with no-option CLTI treated using the novel LA. The primary outcome was a change in the skin perfusion pressure (SPP) after treatment with LA, and the secondary outcomes were changes in the viscosity-related laboratory parameters.

RESULTS

The wound-healing rate was 68.4%. The SPP at 2-3 weeks after series of LA were significantly higher both in the dorsal (41 vs. 53 mmHg, p = 0.037) and plantar (50.0 vs. 61.0 mmHg, p = 0.018) sides, compared to those at baseline. The viscosity-related laboratory markers were also significantly improved after the treatment; low-density lipoprotein-cholesterol (57.0 vs. 43.0 mg/dL, p = 0.002), fibrinogen (333 vs. 258 mg/dL, p < 0.001), and C-reactive protein (0.99 vs. 0.42 mg/dL, p = 0.001).

CONCLUSION

The novel LA significantly increased the SPP and improved relevant laboratory findings.

A novel low-density lipoprotein/fibrinogen apheresis method for chronic limb-threatening ischemia in patients with poor options for revascularization: A multicenter, single-arm clinical trial

INTRODUCTION

Low-density lipoprotein (LDL) apheresis is a treatment option for patients with unhealed chronic limb-threatening ischemia (CLTI) after revascularization. The newly developed AS-25 is a direct hemoperfusion-type apheresis device that differs from conventional LDL apheresis therapy and is designed to specifically adsorb both LDL-C and fibrinogen. We evaluate the efficacy and safety of AS-25.

METHODS

This study included 61 patients whose ulcers failed to heal after revascularization or were ineligible for revascularization. Of these, 50 were undergoing hemodialysis. The primary endpoint was the healing rate of a target lesion of interest (ulcer), using historical data as control.

RESULTS

The ulcer healing rate of 45.9% was significantly higher than the historical data. No significant safety concerns were observed.

CONCLUSIONS

AS-25 was effective in healing ulcers and preventing major amputation even in CLTI refractory patients on hemodialysis, thus showing potential clinical applicability and high significance.

CLINICAL TRIAL REGISTRATION

UMIN study ID UMIN000020336.

The Characteristics of Dialysis Membranes: Benefits of the AN69 Membrane in Hemodialysis Patients

Patients undergoing hemodialysis (HD) experience serious cardiovascular complications, through malnutrition, inflammation, and atherosclerosis. Amputation for peripheral arterial disease (PAD) is more prevalent in patients undergoing HD than in the general population. In addition, revascularization procedures in dialysis patients are often associated with subsequent amputation and high mortality rates. To improve the prognosis of dialysis patients, malnutrition and inflammation must be properly treated, which necessitates a better understanding of the characteristics of dialysis membranes. Herein, the characteristics of several dialysis membranes were studied, with a special reference to the AN69 membrane, noting several similarities to low-density lipoprotein (LDL)-apheresis, which is also applicable for the treatment of PAD. Both systems (LDL-apheresis and AN69) have anti-inflammatory and anti-thrombogenic effects because they use a negatively charged surface for extracorporeal adsorptive filtration from the blood/plasma, and contact phase activation. The concomitant use of both these therapeutic systems may have additive therapeutic benefits in HD patients. Here, we reviewed the characteristics of dialysis membranes and benefits of the AN69 membrane in dialysis patients.

Liposorber® LA-15 system for LDL apheresis in resistant nephrotic syndrome patients

BACKGROUND

Steroid-resistant nephrotic syndrome (SRNS) is a major cause of stage 5 chronic kidney disease (CKD 5) in children. LDL apheresis (LDL-A) is now FDA approved for the treatment of pediatric focal segmental glomerulosclerosis (FSGS). Effective management of hyperlipidemia with LDL-A in SRNS patients may prevent progression of kidney disease and lead to remission. We report a case series of patients who received LDL-A for treatment of SRNS METHODS: We describe five children with SRNS who were treated with 12 sessions of LDL-A. Partial remission (PR) is defined as urine protein to creatinine ratio (UPC) of 0.2-2 (g/g) or decrease in UPC ≥ 50%, and complete remission (CR) is defined as UPC < 0.2 (g/g).

RESULTS

One patient achieved CR and three achieved PR. One patient did not respond to therapy. The earliest that a patient achieved PR was at treatment #10 and some did not respond until after LDL-A was completed. Those who responded stayed in either CR or PR for extended periods of time. LDL-A was successful at significantly reducing LDL (p < 0.001), total cholesterol (p < 0.001), and triglyceride (p < 0.001).

CONCLUSIONS

LDL-A was able to significantly decrease the lipid levels in these patients and induce CR and PR in the majority. The current study confirms previous studies showing those with a higher glomerular sclerosis burden were less likely to respond. LDL-A should be considered in patients with treatment-resistant SRNS and should be considered before there is a high burden of glomerular sclerosis to provide the best chance of success.

Immune-mediated entities of (primary) focal segmental glomerulosclerosis

Focal segmental glomerulosclerosis (FSGS) represents a glomerular scar formation downstream of various different mechanisms leading to podocytopathy and podocyte loss. Recently, significant advances were made in understanding genetic factors, podocyte intrinsic mechanisms, and adaptive mechanisms causing FSGS. However, while most cases of nephrotic FSGS are being treated with immunosuppressants, the underlying immune dysregulation, involved immune cells, and soluble factors are only incompletely understood. Thus, we here summarize the current knowledge of proposed immune effector cells, secreted soluble factors, and podocyte response in immune-mediated (primary) FSGS.

Effects of LDL apheresis on proteinuria in patients with diabetes mellitus, severe proteinuria, and dyslipidemia

BACKGROUND

Patients with diabetes mellitus and severe proteinuria present with poor renal prognoses, despite improvements in diabetes and kidney disease therapies. In this study, we designed a low-density lipoprotein (LDL)-cholesterol apheresis treatment for patients with diabetic nephropathy (DN)/diabetic kidney disease and severe proteinuria. This was a multicenter prospective LICENSE study to confirm the impact of LDL apheresis on proteinuria that exhibited hyporesponsiveness to treatment. In addition, we sought to determine the efficacy and safety of LDL apheresis by comparing the outcomes to those of historical controls in patients with diabetes, refractory hypercholesterolemia, and severe proteinuria.

METHODS

This was a prospective, multicenter study, including 40 patients with diabetes, severe proteinuria, and dyslipidemia. LDL apheresis was performed 6-12 times over a 12-week period. The primary endpoint was the proportion of patients with a decrease in proteinuria excretion of at least 30% in the 6 months after starting therapy. The secondary endpoints included serum creatinine levels and laboratory variables, which were evaluated 4, 6, 12, 18, and 24 months after therapy initiation.

RESULTS

LDL apheresis was performed on 40 registered patients with diabetes. The proportion of cases in which proteinuria decreased by 30% or more after 6 months of LDL apheresis was 25%, which was similar to that of historical controls. The overall survival and end-stage kidney disease-free survival rates were significantly higher in the LICENSE group compared to those in historical controls.

CONCLUSION

Our results suggest that LDL apheresis may be effective and safe for patients with diabetes, proteinuria, and dyslipidemia.

TRIAL REGISTRATION

Trial registration number: jRCTs042180076.

Low-Density Lipoprotein Apheresis in Patients with Acute Kidney Injury Due to Minimal Change Disease Requiring Acute Renal Replacement Therapy

Low-density lipoprotein apheresis (LDL-A) has been developed as a therapy for familial hypercholesterolemia, but LDL-A has also been used as a general treatment for drug-resistant nephrotic syndrome (NS) due to focal segmental glomerulosclerosis (FSGS). The patients with NS due to minimal change disease (MCD) are often difficult to control effective circulating plasma volume, causes acute kidney injury (AKI), and when diuretics are not effective and the respiratory condition of patients worsens, patients require acute renal replacement therapy (ARRT). The effectiveness of LDL-A is not only reduction of serum low-density lipoprotein but also various other benefits. LDL-A might have improved renal hemodynamics by reducing vasoconstrictive eicosanoids and contributed to the therapeutic effect of antiproteinuric drugs such as corticosteroids. We treated a 49-year-old Japanese woman and a 71-year-old Japanese man with AKI caused by NS due to MCD, who required ARRT. Although these patients received ARRT and corticosteroids, their AKI and MCD did not improve sufficiently. We initiated LDL-A treatment for these patients as an additional treatment modality, because their total serum cholesterol levels were high at the time of admission. After the additional LDL-A treatment, both patients were able to discontinue ARRT, because NS and AKI in both patients were improved sufficiently. It is possible that early additional LDL-A is effective for patients with AKI and NS due to MCD who require ARRT, and may help patients discontinue ARRT because of the effect of LDL-A such as improving hypercoagulability and renal hemodynamics and contributing to the therapeutic effect of corticosteroids.

An update on LDL apheresis for nephrotic syndrome

Low-density lipoprotein (LDL) apheresis has been used increasingly in clinical practice for the treatment of renal diseases with nephrotic syndrome (NS), specifically focal segmental glomerulosclerosis (FSGS). Persistent hyperlipidemia for prolonged periods is nephrotoxic and leads to chronic progressive glomerular and tubulointerstitial injury. Effective management of hyperlipidemia with HMG-CoA reductase inhibitors or LDL apheresis in drug-resistant NS patients may prevent the progression of renal disease and, in some patients, resolution of NS symptoms. Available literature reveals beneficial effects of LDL apheresis for NS refractory to drug therapy. Here we update on the current understanding of lipid nephrotoxicity and application of LDL apheresis to prevent progression of renal diseases.

Dextran-Sulfate Plasma Adsorption Lipoprotein Apheresis in Drug Resistant Primary Focal Segmental Glomerulosclerosis Patients: Results From a Prospective, Multicenter, Single-Arm Intervention Study

Background: Focal segmental glomerulosclerosis (FSGS) causes end stage renal disease (ESRD) in significant proportion of patients worldwide. Primary FSGS carries poor prognosis and management of FSGS patients, refractory to standard treatments or resistant to steroids, remains a major challenge. Lipoprotein apheresis is a therapeutic approach for drug resistant primary FSGS and post-renal transplant primary FSGS recurrence. Objectives: To examine the safety and probable benefit at 1, 3, 6, 12, and 24-months following completion of apheresis treatment using Liposorber® LA-15 system in patients with nephrotic syndrome (NS), due to refractory primary FSGS or primary FSGS associated NS, in post renal transplant children. Material and Methods: Prospective, multicenter, single-arm intervention study using Liposorber® LA-15 system. Patients ≤21 years old with drug resistant or drug intolerant NS secondary to primary FSGS with glomerular filtration rate (GFR) ≥60 ml/min/1.73 m² or post renal transplant patients ≤21 years old with primary FSGS associated NS were included in the study. Each patient had 12 dextran-sulfate plasma adsorption lipoprotein apheresis sessions over a period of 9 weeks. All patients were followed up at 1, 3, 6, 12, and 24-months following completion of treatment. Results: Of 17 patients enrolled, six were excluded from the outcome analysis (protocol deviations). Of the remaining 11 patients, all but one have completed apheresis treatments. Three patients were lost to follow-up immediately after completion of apheresis and excluded from outcome analysis. At one-month follow-up, 1 of 7 patients (14.3%) attained partial remission of NS while 2 of 4 subjects (50%) and 2 of 3 subjects (66.7%) had partial/complete remission at 3- and 6-months follow-up, respectively. One of two patients followed up for 12 months had complete remission and one patient had partial remission of NS after 24 months. Improved or stable eGFR was noted in all patients over the follow-up period. Conclusion: The results of our multicenter study showed improvement in the response rates to steroid or immunosuppressive therapy and induced complete or partial remission of proteinuria in some of the patients with drug resistant primary FSGS. The main limitation of our study is the small number of subjects and high dropout rate.

The 1st and the 2nd Italian Consensus Conferences on low-density lipoprotein-apheresis. A practical synopsis and update

The clinical indications and guidelines for low-density lipoprotein (LDL)-apheresis set by the 1st Italian Consensus Conference held in Ostuni in 1990 and completed in 1992, but never published, are reported schematically. In 1994, within the Project "Prevention and control of the factors of the disease (FATMA)" by the Italian National Research Council, subproject 8 "Control of cardiovascular disease", a "Hearing on therapeutic apheresis: need for a target-oriented project" was organised. The meeting was the last scientific initiative on LDL-apheresis supported by public funds in Italy. After roughly two decades of use of LDL-apheresis, new guidelines were required based on the latest scientific evidence. In 2006, the Italian multicentre study on LDL-apheresis Working Group (IMSLDLa-WP), a scientific initiative at national level, was developed. It initially gathered together 19 Italian centres qualified for the application of lipid apheresis and LDL-apheresis (2007-2008), then 23 in 2010, located in the north, south, centre of Italy and in Sicily and Sardinia. The multicentre study aimed to validate the protocol for selecting patients and to create a network between the Italian centres. A secondary objective was the creation of a database of patients with familial hypercholesterolaemia and other severe forms of dyslipidaemia undergoing treatment with LDL-apheresis using the available techniques. Since LDL-apheresis has multidisciplinary treatment indications, the agreement on the new guidelines was reached through a panel of experts, of different medical and surgical specialties, with scientific and medical interest in the treatment indications, application and development of LDL-apheresis. The initiatives of the IMSLDLa-WP led to the 2nd Italian Consensus Conference on LDL-apheresis held in Rome in 2009. The previous and most recent guidelines are reported here synoptically.

Umbilical Cord Blood Transplantation-associated Nephrotic Syndrome Successfully Treated by Low-density Lipoprotein Apheresis

The development of nephrotic syndrome (NS) after umbilical cord transplantation (UBT) has been reported in only four cases to date. We herein report the case of a 50-year-old woman who developed NS 94 days after UBT. She fell into oliguria and required dialysis. A kidney biopsy revealed focal and segmental glomerulosclerosis. Although glucocorticoid monotherapy did not improve her condition, the addition of low-density lipoprotein (LDL) apheresis resulted in remission of NS, a drastic improvement in her renal function, and withdrawal from dialysis. To the best of our knowledge, this is the first report of UBT-associated NS treated with LDL apheresis.

Low-density lipoprotein apheresis for proteinuria in lupus nephritis with intraglomerular foam cells containing cholesterol crystals

A 28-year-old woman with systemic lupus erythematosus was referred to our hospital due to nephrotic-level proteinuria despite approximately 1 year of treatment with 50 to 60 mg/d of prednisolone and 100 to 150 mg/d of cyclosporine with methylprednisolone pulse therapy. Kidney biopsy showed diffuse global lupus nephritis (World Health Organization class 4-G A/C) with many intraglomerular foam cells containing cholesterol crystals. Surprisingly, proteinuria diminished after only 5 low-density lipoprotein (LDL) cholesterol apheresis sessions. This case demonstrated the potential of LDL apheresis to exhibit a remarkable effect on not only focal segmental glomerulosclerosis, but also other types of nephritis, particularly nephritis with intraglomerular foam cells.

Lipoprotein glomerulopathy treated with LDL-apheresis (Heparin-induced Extracorporeal Lipoprotein Precipitation system): a case report

Introduction

Lipoprotein glomerulopathy is a glomerulonephritis which was described for the first time by Saito in 1989 and is currently acknowledged as a separate nosological entity. It is histologically characterized by a marked dilatation of the glomerular capillaries and the presence of lipoprotein thrombi in the glomerular lumens. The dyslipidemic profile is similar to that of type III dyslipoproteinemia with Apolipoprotein E values that are often high; proteinuria and renal dysfunction are present. Proteinuria often does not respond to steroid and cytostatic treatments.

The phenotypic expression of lipoprotein glomerulopathy is most probably correlated to a genetic alteration of the lipoprotein metabolism (mutation of the Apolipoprotein E coding gene). In literature, lipoprotein glomerulopathies have mainly been reported in Japanese and Chinese subjects, except for three cases in the Caucasian race, reported in France and the USA.

Case presentation

We describe the case of a 60-year-old female, Caucasian patient suffering from lipoprotein glomerulopathy, carrier of a new mutation on the Apolipoprotein E gene (Apolipoprotein E_MODENA), and treated successfully with low density lipoprotein-apheresis with the Heparin induced extracorporeal lipoprotein precipitation system. After a first phase of therapeutic protocol with statins, the patient was admitted for nephrotic syndrome, renal failure and hypertension. Since conventional treatment alone was not able to control dyslipidemia, aphaeretic treatment with heparin-induced Extracorporeal Lipoprotein Precipitation - apheresis (HELP-apheresis) was started to maintain angiotensin converting enzyme inhibitor therapy for the treatment of hypertension. Treatment with HELP-apheresis led to a complete remission of the proteinuria in a very short time (four months), as well as control of hypercholesterolemia and renal function recovery.

Conclusion

According to this case of lipoprotein glomerulopathy, we believe that renal damage expressed by proteinuria correlates to the levels of lipids and, furthermore, the treatment with HELP-apheresis, by lowering low-density lipoprotein cholesterol and triglycerides, may be considered as a therapeutic option in synergy with pharmacological treatment in the treatment of lipoprotein glomerulopathy.

Preparation of heparin-immobilized PVA and its adsorption for low-density lipoprotein from hyperlipemia plasma

In this study, heparin was covalently coupled by glutaraldehyde to Poly(vinyl alcohol) [PVA] in solid-liquid two-phase reaction system by two-step synthesis method to prepare a LDL-selective adsorbent. The parameters (the material ratio, reaction time and dosage of catalyzer) were investigated to evaluate their effect upon the immobilized amount of heparin onto the surface of PVA, IR was used to verify the covalent immobilization result and the heparin-modified PVA was also undergone the evaluation of its adsorption capability for low-density lipoprotein from hyperlipemia plasma, and its hemocompatibility was preliminarily evaluated by platelet adhesion test. Results showed: (1) under optimized reaction conditions the highest immobilization amount of heparin onto PVA surface within the experiments of this study has been obtained; (2) the optimized reaction conditions were: (i) at the refluxing temperature 78 degrees C; (ii) the material ratio of "PVA(g): 50% glutaraldehyde (ml)" was about "1:3"; (iii) the reaction time was about 5 h; and (iv) the amount of catalyzer (concentrated HCL) was about 1% of the 50% glutaraldehyde; (3) within the experiments of this study the highest immobilization amount would be up to 25 microg heparin on the surface of per g PVA granules; (4) the heparin-modified PVA granules showed significant adsorption for LDL under faintly alkaline environment (pH=7.2-9.5) ; (5) The result of platelet adhesion test showed no platelet adhered to its surface. Therefore, immobilization of heparin onto the surface of a support is one approach to prepare a kind of LDL adsorbent for blood purification.