The German Lipoprotein Apheresis Registry-Summary of the ninth annual report

During 2012-2020, 89 German apheresis centers collected retrospective and prospective observational data of 2028 patients undergoing regular lipoprotein apheresis (LA) for the German Lipoprotein Apheresis Registry (GLAR). More than 47 500 LA sessions are documented in GLAR. In 2020, all patients treated with LA showed a high immediate median reduction rate of LDL-C (68.2%, n = 1055) and Lp(a) (72.4%, n = 994). Patient data were analyzed for the incidence rate of major coronary events (MACE) 1 and 2 years before the beginning of LA treatment (y-2 and y-1) and prospectively up to 7 years on LA (y + 1 to y + 7). During the first 2 years of LA (y + 1 and y + 2), a MACE reduction of 78% was observed. Current analysis of GLAR data shows very low incidence rates of cardiovascular events in patients with high LDL-C and/or high Lp(a) levels, progressive ASCVD, and maximally tolerated lipid lowering medication regular by LA results.

Adsorptive cytapheresis for ulcerative colitis with focus on removing plateletets and platelet-aggregates

INTRODUCTION

Platelet abnormalities and secondary thrombocytosis are clinical features of ulcerative colitis (UC) and seem to play a relevant role in the pathogenesis. This work analysed the adsorption characteristics of the adsorber Immunopure.

METHODS

A prospective study was performed to investigate the module in vitro with blood from healthy donors in a down-scaled recirculation model and in vivo in six patients suffering from UC. Furthermore, adsorber beads were investigated by immunofluorescence analyses. Apheresis was performed over five weeks at weekly intervals.

RESULTS

In vitro as well as in vivo, the module showed a strong adsorption of platelets, monocytes, CD14⁺ CD16⁺ monocytes, neutrophils and platelet leukocyte aggregates (PLAs). Five of the six patients benefited from the treatment (83%), and four (67%) went into remission. On average, the CAI was reduced by 6.4 points.

CONCLUSION

Immunopure treatments improved the course of the disease and were well tolerated. The module strongly adsorbs platelets and platelet-aggregates. This article is protected by copyright. All rights reserved.

Using the World Apheresis Association Registry Helps to Improve the Treatment Quality of Therapeutic Apheresis

Therapeutic apheresis (TA) is prescribed to patients that suffer from a severe progressive disease that is not sufficiently treated by conventional medications. A way to gain more knowledge about this treatment is usually by the local analysis of data. However, the use of large quality assessment registries enables analyses of even rare findings. Here, we report some of the recent data from the World Apheresis Association (WAA) registry. Data from >104,000 procedures were documented, and TA was performed on >15,000 patients. The main indication for TA was the collection of autologous stem cells (45% of patients) as part of therapy for therapy. Collection of stem cells from donors for allogeneic transplantation was performed in 11% of patients. Patients with indications such as neurological diseases underwent plasma exchange (28%). Extracorporeal photochemotherapy, lipid apheresis, and antibody removal were other indications. Side effects recorded in the registry have decreased significantly over the years, with approximately only 10/10,000 procedures being interrupted for medical reasons.

Conclusion

Collection of data from TA procedures within a multinational and multicenter concept facilitates the improvement of treatment by enabling the analysis of and feedback on indications, procedures, effects, and side effects.

Novel Leucocyte/Thrombocyte Apheresis for Induction of Steroid-Free Remission in Ulcerative Colitis: A Controlled Randomized Pilot Study

BACKGROUND AND AIMS

In active ulcerative colitis [UC] refractory to mesalazine, escalation to either steroids or immunosuppression is common practice. The efficacy and safety of alternative escalation therapy with a novel leukocyte apheresis device were studied.

METHODS

This was a prospective, randomized, controlled multicentre pilot study comparing leukocyte apheresis with prednisolone in refractory UC (disease activity index [DAI] ≥ 4 and ≤8). Group A received weekly apheresis over five consecutive weeks. Group P received oral prednisolone 40 mg/day tapered to 0 mg at week 6. The primary end point was steroid-free clinical remission [DAI ≤ 2] at week 12. Clinical response was also analysed.

RESULTS

Twenty-four patients were enrolled, 13 of whom were randomized into group A and 11 into group P. Clinical remission off steroids at week 12 was achieved in 3/12 patients [25.0%] with apheresis and 2/10 [20.0%] with prednisolone [p = 1.0]. The response rate after 12 weeks was 75.0% in group A and 50.0% in group P. Mean DAI scores improved in both treatment groups [p = 0.008]. C-reactive protein decreased from 6.0 ± 5.3 to 3.8 ± 3.7 mg/L at 12 weeks in group A and increased from 5.2 ± 6.0 to 6.3 ± 7.9 mg/mL in group P. Both treatments were well tolerated. No unexpected serious adverse events were seen in group A. In group P one symptomatic infection with Clostridium difficile occurred.

CONCLUSIONS

In patients with active UC refractory to mesalazine a novel leukocyte apheresis showed promising results. A comparison with prednisolone revealed similar therapeutic effectivity and excellent safety, providing the chance to escalate without systemic steroids.

Treatment-related and health-related quality of life in lipoprotein apheresis patients

BACKGROUND

There is evidence for beneficial effects of lipoprotein apheresis (LA) in terms of reduction of cardiovascular events and interventions, but quality of life (QOL) in LA patients has only been explored in small samples.

OBJECTIVE

In this study, both LA- or treatment-related and health-related QOL (HRQOL) were assessed in 206 LA patients.

METHODS

Mental and physical HRQOL of the LA patients was assessed by means of the SF-12 as well as the EQ-5D. Physical complaints were assessed by the Patient Health Questionnaire-15 and LA- or treatment-related QOL by the Apheresis Quality of Life Form, developed for this study.

RESULTS

Comparison with general population norms showed that LA patients scored significantly lower on HRQOL and significantly higher on physical complaints. A higher perceived impact of the treatment proved to have a significant negative association with HRQOL and a positive one with physical complaints.

CONCLUSION

Previous studies reported higher levels of QOL in LA patients. This study showed that treatment-related QOL contributes to HRQOL and physical complaints in LA patients. While many patients do not experience LA as a real burden and report positive effects of the treatment, there is also an important group of patients for whom this is not the case. Although the impact on QOL of LA patients does most probably not outweigh the cardiovascular benefits of the treatment, it is important to screen treatment-related QOL in LA patients to optimize care in a personalized way. Future research is needed to compare QOL in LA with non-LA patients with similar medical conditions.

Granulocyte/monocyte adsorptive apheresis for the treatment of therapy-refractory chronic active ulcerative colitis

OBJECTIVES

Current options for patients with steroid-dependent, chronic-active ulcerative colitis (UC) with insufficient response/intolerance to immunosuppressants (ISs) and/or biologics are limited. The aim of this study was to assess the long-term outcome of granulocyte/monocyte adsorptive (GMA) apheresis (Adacolumn^®) in this population.

MATERIALS AND METHODS

Ninety five adults with steroid-dependent active UC and insufficient response/intolerance to IS and/or TNF inhibitors received 5-8 aphereses in a single induction series of ≤10 weeks. Endpoints included rates of remission (clinical activity index [CAI] ≤ 4) at weeks 24 and 48.

RESULTS

Of 94 patients (ITT population), remission and response rates were 34.0% and 44.7% at week 24, and 33.0% and 39.4% at week 48. Among 30 patients with prior failure of IS and biologics, 33.3% and 20.0% were in remission at weeks 24 and 48. At both weeks, 19.2% of patients achieved steroid-free remission. Sustained remission or response occurred in 27.7% of patients at 48 weeks. The cumulative colectomy rate at week 96 was 23.4%. Safety was consistent with previous findings.

CONCLUSIONS

This study confirms findings of the 12-week interim analysis and demonstrates that GMA apheresis provides a safe and beneficial long-term outcome for patients with chronic active UC resistant/intolerant to IS and/or TNF inhibitors.

On-Line Hemodiafiltration with Pre- and Postdilution: Impact on the Acid-Base Status

With on-line formation of the substitution fluid, high substitution rates in predilution (PRD) and postdilution (POD) can be obtained (Fresenius 4008 On-Line HDF, Gambro AK 100 Ultra). The substitution fluid is branched off from the dialysate produced by the dialysate delivery system of the HDF machine. Under these conditions it is desirable to consider the effect of the different treatment modes on the acid-base status. Using Fresenius 4008 On-Line HDF machines, ESRD-patients were treated alternately with high-flux hemodialysis (HD), postdilution HDF (POD-HDF) and predilution HDF (PRD-HDF), while all other treatment parameters were kept constant, in particular the bicarbonate dialysate concentration. Plasma-HCO3, - pH and -pCO2 were measured and compared with the results of a multicompartment bicarbonate model developed by Thews. Also plasma-pO2 and K+ were measured. The results showed no significant differences between HD, POD- and PRD-HDF. Acidosis was corrected effectively and no excessive compensation of the acid-base disturbance was observed.

On-Line Hemodiafiltration with Pre- and Postdilution: A Comparison of Efficacy

Since the introduction of on-line substituate preparation, high substituate rates (Qs) in pre- and postdilution for hemodiafiltration (HDF) procedures can be realized. During postdilution HDF (POD-HDF) and additional convective removal is possible, but in vivo Qs is limited to approx. 1/3Qb (bloodflow). With predilution HDF (PRD-HDF) higher Qs and therefore high convective transport rates by ultrafiltration can be reached. On the other hand the blood concentration is diminished by predilution. Further decrease of the diffusive transport is caused by reduced dialysate flow Qd due to separation of the substituate from the dialysate (Fresenius 4008 On-Line HDF, Gambro AK100 Ultra). The theoretical description of the combined diffusive-convective transport is limited to 1-dimensional models and small UF-rates. Therefore for practical and theoretical purposes the assessment of the efficacy of on-line PRD-HDF and POD-HDF in different molecular weight ranges is desirable. By means of in vitro experiments the effective clearances Keff of hemodialysis (HD, dialyzer: Fresenius F60) for urea, creatinine, vitamin B12 and inulin were compared with measured and theoretical Keff of POD- and PRD-HDF. The theoretical expectation is confirmed that Keff for small molecular weight substances decreases slightly with PRD-HDF and increases for larger molecules. In the case of POD-HDF Keff for small molecular weight substances increases slightly and strongly for larger molecules. In vivo experiments were performed to measure the real substance removal from patient's blood and to figure out the impact of dialysate flow (collection of the used dialysate during the 1. treatment hour and concentration measurements for urea, creatinine, phosphate, ß2-MG). The results show that the substraction of Qs from Qd reduces Keff for urea, creatinine and phosphate but not for ß2-MG. PRD-HDF with Qd = 500 ml/min is significantly less effective for small molecules than HD. There is no significant difference of Keff for urea, creatinine, phosphate during HD and PRD-HDF with Qd = 800 ml/min, but a significant increase of 10-15% for POD-HDF Keff for ß2-MG increases by 75% for PRD-HDF and 95% for POD-HDF compared with HD (Qd = 500 ml/min).

Efficacy of lipid reduction with DALI and MONET

BACKGROUND

Lipidapheresis techniques are increasingly used to treat drug-resistant hyperlipidemia but few efficacy studies under routine application are available. In this multicenter observational study we investigated direct adsorption of lipoproteins (DALI) and lipoprotein filtration (MONET) for the short and the long-term effects on lipid-lowering effects.

METHODS

Data of 122 apheresis patients from 11 centers (DALI: n = 78, MONET: n = 44) were prospectively collected for a period of 2 years. Routine lipid measurements were evaluated (2154 DALI and 1297 MONET sessions). It was investigated whether the relative reduction of LDL-C during apheresis session achieves at least 60%. Also relative reduction of total cholesterol, HDL, triglyceride, and Lp(a) were analyzed.

RESULTS

The relative reduction of LDL-C was at least 60%: DALI: 70.62%, 95% CI = [69.34; 71.90] and MONET: 64.12%, 95% CI = [60.79; 67.46]. Also triglycerides were reduced with both systems: DALI 38.63%, 95% CI = [33.95; 43.30] vs. MONET 57.68%, 95% CI = [51.91; 63.45]. Relative reductions of total cholesterol were in the range of 50% (DALI 95% CI = [46.49; 49.65] MONET 95% CI = [48.93; 55.26]) and of Lp(a) in the range of 65% (DALI 95% CI = [61.92; 65.83] MONET 95% CI = [63.71; 70.30]. HDL reduction was: DALI 15.01%, 95% CI = [13.22; 16.79] and MONET 22.59%, 95% CI = [19.33; 25.84]. For both devices treated patient plasma/blood volume and in case of DALI the use of the larger adsorber configurations (DALI 1000 and DALI 1250) were independent positive predictors of the relative reduction of LDL-C and of Lp(a).

CONCLUSIONS

Both systems effectively improved lipid profile and reduced atherogenic lipids. The results point to the importance of the individualized application of these valuable therapies to achieve clinical targets.

Alirocumab in patients with heterozygous familial hypercholesterolaemia undergoing lipoprotein apheresis: the ODYSSEY ESCAPE trial

AIM

To evaluate the effect of alirocumab on frequency of standard apheresis treatments [weekly or every 2 weeks (Q2W)] in heterozygous familial hypercholesterolaemia (HeFH).

METHODS AND RESULTS

ODYSSEY ESCAPE (NCT02326220) was a double-blind study in 62 HeFH patients undergoing regular weekly or Q2W lipoprotein apheresis. Patients were randomly assigned (2:1, respectively) to receive alirocumab 150 mg (n = 41) or placebo (n = 21) Q2W subcutaneously for 18 weeks. From day 1 to week 6, apheresis rate was fixed according to the patient's established schedule; from weeks 7 to 18, apheresis rate was adjusted based on the patient's low-density lipoprotein cholesterol (LDL-C) response in a blinded fashion. Apheresis was not performed when the LDL-C value was ≥30% lower than the baseline (pre-apheresis) value. The primary efficacy endpoint was the rate of apheresis treatments over 12 weeks (weeks 7-18), standardized to number of planned treatments. In the alirocumab group the least square (LS) mean ± SE (95% confidence interval [CI]) per cent change in pre-apheresis LDL-C from baseline at week 6 was -53.7 ± 2.3 (-58.2 to - 49.2) compared with 1.6 ± 3.1 (-4.7 to 7.9) in the placebo group. The primary efficacy endpoint showed statistically significant benefit in favour of alirocumab (Hodges-Lehmann median estimate of treatment difference: 0.75; 95% CI 0.67-0.83; P < 0.0001). Therefore, alirocumab-treated patients had a 0.75 (75%) additional reduction in the standardized rate of apheresis treatments vs. placebo-treated patients. During this period, 63.4% of patients on alirocumab avoided all and 92.7% avoided at least half of the apheresis treatments. Adverse event rates were similar (75.6% of patients on alirocumab vs. 76.2% on placebo).

CONCLUSIONS

Lipoprotein apheresis was discontinued in 63.4% of patients on alirocumab who were previously undergoing regular apheresis, and the rate was at least halved in 92.7% of patients. Alirocumab was generally safe and well tolerated.

Adverse events in apheresis: An update of the WAA registry data

Apheresis with different procedures and devices are used for a variety of indications that may have different adverse events (AEs). The aim of this study was to clarify the extent and possible reasons of various side effects based on data from a multinational registry. The WAA-apheresis registry data focus on adverse events in a total of 50846 procedures in 7142 patients (42% women). AEs were graded as mild, moderate (need for medication), severe (interruption due to the AE) or death (due to AE). More AEs occurred during the first procedures versus subsequent (8.4 and 5.5%, respectively). AEs were mild in 2.4% (due to access 54%, device 7%, hypotension 15%, tingling 8%), moderate in 3% (tingling 58%, urticaria 15%, hypotension 10%, nausea 3%), and severe in 0.4% of procedures (syncope/hypotension 32%, urticaria 17%, chills/fever 8%, arrhythmia/asystole 4.5%, nausea/vomiting 4%). Hypotension was most common if albumin was used as the replacement fluid, and urticaria when plasma was used. Arrhythmia occurred to similar extents when using plasma or albumin as replacement. In 64% of procedures with bronchospasm, plasma was part of the replacement fluid used. Severe AEs are rare. Although most reactions are mild and moderate, several side effects may be critical for the patient. We present side effects in relation to the procedures and suggest that safety is increased by regular vital sign measurements, cardiac monitoring and by having emergency equipment nearby.

World apheresis registry data from 2003 to 2007, the pediatric and adolescent side of the registry

OBJECTIVES

Paediatric patients are a special group in apheresis. It is general accepted to use adult indications in paediatric patients, but data in this age group are rare. In order to provide more information of apheresis practise in children and young adults (<21a) we will report of knowledge learnt by data from the registry from 2003 until 2007.

METHODS

This is a web-based registry. A link is available from the WAA homepage (www.worldapheresis.org). So far data from 12,448 procedures have been included. Six hundred and twelve procedures were performed in 135 children and young adults (308 procedures<16a, 237 from 17 to 20a, and 67 with 21a) representing 5% of the total population. The median age was 14 years (range 1-21 years), 74 male and 61 female. These data were entered by 15 centres with a frequency of in median 18 aphereses in young patients per centre (range 1-287) from 2003 to 2007.

RESULTS

Main indications: haematological diseases and also nephrological, and neurological. The type of aphereses was mainly Leukapheresis (196, 33%), plasma exchange (149, 25%), photopheresis (127, 21%), and lipid aphereses (79, 13%). Blood access: peripheral vessels in 305 procedures (50%, compared to 73% in adults), central venous catheter in 239 (38%), and AV-fistula in 2% and 0.3%, and in 8 (1.31%) procedures an arterial line was used. Anticoagulation was mostly by ACD (71%), heparin (18% or the combination of both (3%). 39 adverse events (AE) were registered in 22 (=3.59%) of the procedures, mostly graded as mild. Treatment was interrupted in 14 procedures (2.29%). AE's were abdominal pain, anaphylactic shock, flush, hyper- and hypotension, nausea, vertigo, cephalea and need for sedation and technical problems with the device and problems with the venous access. The rate of AE's was similar for stem cell harvesting and for plasma exchange (4% and 4.7%, respectively).

CONCLUSION

The paediatric data compared to the whole registry data set are showing that aphereses are performed as safe in paediatrics as in adults. Centres are mostly handling only a few cases younger than 21. Therefore more exchange of information and experience in paediatric apheresis is warranted.

Reduction of dendritic cells by granulocyte and monocyte adsorption apheresis in patients with ulcerative colitis

The influence of the granulocyte/monocyte apheresis (GMCAP) on cell populations participating in mechanisms of tolerance, e.g. dendritic cells (DCs), is still not very clear. In a first step, we aimed to investigate changes in the DC population of patients suffering from ulcerative colitis (UC) (n = 13) compared to healthy subjects (n = 9). In a second step, we studied the changes in peripheral DCs in a small group of patients with active UC before and after Adacolumn apheresis (n = 7). For this purpose, plasmacytoid and myeloid DCs and their maturation markers CD40, CD80, and CD86 were measured using four-color flow cytometry in the peripheral blood. After apheresis, and in acute flare-ups, we identified a significantly lower number of lymphocytes, plasmacytoid, and myeloid DCs. In conclusion, the additional removal of peripheral DCs by GMCAP, which otherwise would contribute to the inflammatory process in the gut, may lead to a higher tolerogeneic status towards luminal antigens.

Leukocytapheresis (LCAP) in the management of chronic active ulcerative colitis--results of a randomized pilot trial

Recent studies suggest that leukocytapheresis with Cellsorba is a valuable therapy for ulcerative colitis after failure of conventional treatment. In this study the potential of leukocytapheresis to induce remission in refractory chronic colitis under the conditions of European treatment guidelines was investigated. The therapeutic benefit of leukocytapheresis in the maintenance of remission was additionally elucidated. Twenty patients were treated weekly for 5 weeks. A significant decrease in the activity index was observed. Fourteen patients achieved clinical remission, and mucosal healing was observed endoscopically in six patients. After randomization these 14 patients in remission entered a second period of either monthly leukocytapheresis or no further treatment. In both groups steroids were tapered down. After 6 months, only one patient in the control group remained in remission, in contrast to five of eight patients in the leukocytapheresis group. In conclusion, leukocytapheresis may offer a therapeutic option in the induction and the maintenance of remission in chronic active ulcerative colitis.

In vitro and in vivo evaluation of Adacolumn cytapheresis in healthy subjects

Adacolumn is a medical device for adsorptive cytapheresis. It has been developed for selective adsorption of granulocytes and monocytes from peripheral blood of patients with immune disorders, such as autoimmune diseases and chronic inflammatory diseases. A double blind sham-controlled crossover study design was used in order to evaluate in vivo biological responses of leukocytes as well as biocompatibility during and after Adacolumn cytapheresis in healthy volunteers. In addition, experiments were undertaken to further evaluate leukocyte reactions to Adacolumn carrier (G-1: cellulose diacetate) beads in vitro. Six healthy volunteers, 4 males and 2 females, with a mean age of 26.7 years were randomly assigned to one of the two treatment arms in a crossover fashion. Three subjects received a single Adacolumn treatment, followed by a single sham treatment at an interval of 7 days. The other three subjects received the two treatments in reverse order. All subjects were followed up 7 days after the last treatment. Additionally, in vitro investigations were carried out using blood from the healthy donors to examine the effect of G-1 beads on granulocyte functions. In vitro exposure of human peripheral blood to G-1 beads caused downregulation of L-selectin expression and upregulation of Mac-1 expression on granulocytes, leading to a marked reduction of adhesive capacity of granulocytes to endothelial cells. The exposure also led to decreased granulocyte chemotactic activity to IL-8. The number of granulocytes and monocytes clearly decreased during Adacolumn cytapheresis. Granulocytes showed marked phenotypic changes of L-selectin(Low) and Mac-1(Hi) after passing through Adacolumn in vivo. Expression of TNF-alpha and chemokine receptors was downregulated. In addition, TNF-alpha and IL-1beta producing capacity of peripheral blood leukocytes was decreased after Adacolumn cytapheresis and these changes lasted even one week after the cytapheresis. The level of complement fragments, C3a and C5a, increased, while bradykinin concentration did not change during Adacolumn cytapheresis. Exposure of human peripheral blood to G-1 beads, both in vitro and in vivo, caused a significant reduction of adhesive capacity and proinflammatory cytokine producing capacity of peripheral blood leukocytes. Such changes were not observed after sham apheresis. Despite complement activation, tolerability of Adacolum cytapheresis was not influenced. These findings may at least partly explain the beneficial effect of Adacolumn cytapheresis in the treatment of autoimmune diseases.

Pilot clinical study of Adacolumn cytapheresis in patients with systemic lupus erythematosus

The aim of this study is to investigate the clinical effects of cytapheresis using the Adacolumn system (selective removal of circulating monocytes and granulocytes by means of an extracorporeal type column) in patients with active systemic lupus erythematosus (SLE). An open uncontrolled multicenter pilot study was conducted in 18 SLE patients who were showing a SLEDAI score of 8 or more under conventional medication. Patients with lupus nephritis (>class 1, WHO classification) were excluded. Extracorporeal cytapheresis with the Adacolumn system was administered once a week for five consecutive weeks. The efficacy of the treatment was evaluated using the SLEDAI for 10 weeks after the first cytapheresis session. The median SLEDAI decreased from 16 at baseline to six at week 11 (10 weeks after the first apheresis) (p<0.001). Significant improvements in musculoskeletal and dermal systems were observed. Arthritis and alopecia were present in 14 and nine patients at baseline and this number decreased to five and one patients, respectively by week 11. Three mild and one moderate adverse events out of the 42 reported events were judged 'probably related' to the treatment; no serious adverse events were reported. Selective removal of monocytes and granulocytes from the blood in an extracorporeal circulation system was associated with clinical improvement in this small series of patients with SLE. Since this approach seems not to have the disadvantages of pharmacological immunosuppression, further controlled studies of Adacolumn cytapheresis are warranted in SLE.

World apheresis association—world apheresis registry

In 2002 WAA decided to start a world-wide apheresis registry to gain insight into the extent of treatment, adverse events, and to facilitate contacts among centers when treatment indications are rare and experience limited. Stem cell and other blood products collections intended for therapeutic application can also be entered. The WAA planned to use the French Registry. Its translation into English has not been accomplished and the fiscal obligations for that registry has not, as yet, been determined or considered and approved by the WAA Board. From Dec 2002 the proposed registry (a merged version of the French, Canadian and Swedish registries) can be immediately implemented. We now cordially invite all centers to join that registry. Please, also inform colleagues at other centers in your country to join. E-mail and address lists of colleagues in your country who have not registered will be welcomed. The site is at: Go to World Apheresis Registry; Login code to test the Registry is: al61tms. Then apply for a specific login code for your center. We welcome you to this registry for your input of data. You will not be charged any registration fee. The registry includes a randomization system that can be used for local or multi center studies (randomization by in-center basis allows you to make your own studies). It includes a formula that increases the chance to get a more even distribution between groups also for smaller sample sizes.

Comparison of two filter combinations for low-density lipoprotein apheresis by membrane differential filtration: a prospective crossover controlled clinical study

Membrane differential filtration is an accepted procedure for the extracorporeal removal of low-density lipoprotein (LDL). Reduction rates largely depend on the nature of the membranes and are ideally evaluated in a crossover study design. Four patients who had been treated by LDL apheresis for at least 6 months were included. Six consecutive weekly sessions (40 ml plasma/kg body weight) were scheduled per system (Plasmacure PS06/Evaflux Eval 5A [Kuraray] versus Plasmaflo OP05W/Cascadeflo AC1770 [Asahi]). Laboratory measurements indicated reductions of plasma concentrations for fibrinogen (37% [Kuraray] versus 44% [Asahi]), IgG (15% versus 20%), IgA (24% versus 28%), IgM (63% versus 53%), and total protein (11% versus 16%). Total cholesterol was eliminated by 52% versus 49%, LDL by 67% versus 66%, triglycerides by 56% versus 41%, and high-density lipoprotein by 10% versus 20%. Three therapies employing the Asahi filter combination were terminated prematurely due to saturation of the plasma fractionator. In conclusion, despite similar physical properties, the membranes differ significantly concerning selectivity and sensitivity to saturation.

Selective removal of circulating immune complexes from patient plasma

The principle of a patient-specific immunoadsorber (PsIA) is demonstrated. Studies with model systems (HSA/anti-HSA) on immobilization, stability, and leakage form the basis for the presented fast-performance liquid chromatography (FPLC) and batch experiments, which were conducted using two different protein A adsorbers and autologous and heterologous PsIA systems. Experiments to determine the binding capacity of protein A adsorbers and PsIAs are described. In all experiments, the adsorption of plasma IgG, total protein, and C1q and C3d circulating immune complexes were measured. Plasma of patients with autoimmune diseases (rheumatoid arthritis, systemic lupus erythematosus) was investigated. Analysis was performed in both the initial plasma and the flow-through or supernatant. Results of the investigations using FPLC and batch experiments were compared. Autologous PsIA systems are suitable for the selective removal of elevated levels of circulating immune complexes in the plasma.

Online hemodiafiltration versus acetate-free biofiltration: a prospective crossover study

Online hemodiafiltration (online HDF) and acetate-free biofiltration (AFB) are 2 innovative renal replacement therapies. Convincing evidence has shown that both techniques are superior to conventional hemodialysis in many aspects. The aim of the present investigation was to compare online HDF and AFB in 12 stable maintenance hemodialysis patients in a prospective, randomized crossover trial. Twelve stable dialysis patients, age 49.7 +/- 11.3 years and on dialysis for 83.5 +/- 76.7 months, were treated prospectively and randomly by either AFB, predilution HDF (pre-HDF), or postdilution HDF (post-HDF) for a total of 36 weeks using exclusively F60S high-flux dialyzers. Routine blood biochemical tests, bone metabolism parameters, and clearance for both small and larger molecular weight substances were measured at defined intervals. During the trial period inter- and intradialysis symptoms, e.g., hypotensive episodes and intradialysis arterial blood gas analyses, were recorded. Both online HDF and AFB were well accepted by the overwhelming majority of patients and also by the dialysis staff. Pretreatment sodium, total and ionized calcium, chloride, bicarbonate, and urea did not differ within or between the 3 treatment groups. Potassium increased slightly in HDF patients while phosphate and beta2-microglobulin (beta2-M) decreased in all groups. After dialysis, AFB patients exhibited a significantly higher bicarbonate concentration and lower potassium level when identical potassium concentrations in dialysate were used. Patients receiving AFB manifested less intradialysis partial pressure of oxygen drop and partial pressure of carbon dioxide rise than those on HDF treatments. HDF treatments could afford higher single-pool and double-pool Kt/V, higher effective urea and beta2M clearance, and lower total interdialysis symptom scores than the AFB treatment method. While bone metabolism parameters did not differ between the 3 dialysis modalities, some parameters such as deoxypyridinoline in HDF and osteocalcin, pyridinoline, and deoxypyridinoline in AFB deteriorated at the end of the crossover study. Aluminum concentration decreased progressively to about one-third of prestudy values at the end of the study with all 3 treatments. AFB was associated with a lower predialysis mean arterial pressure (MAP), a smaller drop in MAP during treatment, and similar hypotension episodes compared with the 2 HDF treatments. Albumin concentration showed a trend to decrease during the first 2 months of the trial period followed by a slight increase thereafter but still significantly lower than initial value at the end of crossover. Both online HDF and AFB share most of the features of optimal renal replacement therapy. Online HDF is superior to AFB in such aspects as increased delivered dialysis dose both for small and larger molecular weight toxins and less interdialysis symptoms. On the other hand, AFB is associated with a smaller effect on arterial blood gas values and improved intradialysis hemodynamic tolerance. Some dialysis-related symptoms and complications in the case of our AFB practice could be attributable, at least in part, to low dialysate calcium level.

Changes in lymphocytic cluster distribution during extracorporeal immunoadsorption

The success of apheresis treatment is often measured as a decrease in the detected antibodies and an improvement in different disease-related scores. Sometimes, however, the seriousness of the disease does not correlate with the antibody level. During a period of 8 years, 15 patients (3 myasthenia gravis, 1 multiple sclerosis, 2 systemic lupus erythematosus, 3 alloimmunized kidney transplant, 6 rheumatoid arthritis) were treated by protein A immunoadsorption. Lymphocyte subpopulations (activated T cells, cytolytic T cells, B cells, natural killer cells) and inflammatory proteins (ferritin, C-reactive protein, alpha1-antitrypsin, alpha2-macroglobulin) were analyzed. After observing clinical outcomes, the patients could be divided into 2 groups, respectively: Group 1, responding patients with remission of disease; and Group 2, delayed-responding patients, who required chronic treatment. Group 1 patients characteristically showed a greater increase in activated T and cytolytic T cells which correlated with a greater decrease of B cells. It might be possible that protein A immunoadsorption induced immunomodulation. Further immunological investigation is required to verify these findings.

Extracorporeal fibrinogen adsorption--efficacy, selectivity and safety in healthy subjects and patients with foot ulcers

The elimination of fibrinogen from plasma improves plasma viscosity and whole blood viscosity. For extracorporeal adsorption of fibrinogen the pentapeptide gly-pro-arg-pro-lys was coupled to sepharose CL-4B. Columns containing 100 ml of coupled sepharose CL-4B were used to eliminate fibrinogen from the plasma of 8 healthy male subjects (mean age 27.4 +/- 4.3 years, height 180.9 +/- 8.3 cm, weight 85.1 +/- 13.6 kg). Four treatments were performed in each proband (days 1, 2, 4 and 7). Plasma fibrinogen concentration was lowered from 221.1 +/- 39.0 to 123.5 +/- 21.7 mg/dl (2275 +/- 477 ml plasma treated) by the first treatment, from 172.8 +/- 42.3 to 105.6 +/- 16.5 mg/dl (1609 +/- 761 ml) by the second, from 140.5 +/- 13.8 to 98.8 +/- 8.6 mg/dl (1224 +/- 118 ml) by the third and from 160.2 +/- 23.6 to 106.4 +/- 9.7 mg/dl (1513 +/- 521) by the fourth. Plasma viscosity was improved from 1.40 +/- 0.18 mPa s before the first treatment to 1.23 +/- 0.06 mPa s after fourth treatment, whole blood viscosity from 4.49 +/- 0.36 mPa s to 3.83 +/- 0.27 mPa s (P < 0.01). No clinical side effects and no clinically relevant change of laboratory parameters including in vitro tests on thrombocyte function were observed. Seven men and three women (48-75 years old, 9 patients suffered from diabetes mellitus, one patient from peripheral arterial occlusive disease, 5 patients were on regular hemodialysis) were treated by fibrinogen adsorption. Each column contained 135 ml of coupled sepharose CL-4B. Treatments were scheduled on day 1, 2, 4, 6, 8, 10, 13, 16, 19, 22, 25 and 28. 144 treatments with fibrinogen adsorption were performed. No clinical side effects due to the fibrinogen-adsorption procedure were observed. In these 10 patients the fibrinogen concentration before the first treatment was 473.7 +/- 183.7 mg/dl. In the first treatment session it was lowered to 241.4 +/- 125.8 mg/dl by treating 4270 +/- 1180 ml of plasma. In the following 134 treatments the pre-treatment concentration of fibrinogen was 262.6 +/- 83.4 mg/dl, the post-treatment concentration was 120.6 +/- 37.2 mg/dl. The mean volume of plasma treated was 3737 +/- 1643 ml, the mean duration of a treatment session (except the first treatment) was 143.7 +/- 63.1 min. In 7 patients a mean post-treatment fibrinogen concentration of < or = 123 mg/dl was obtained, in the other patients 133, 177 and 184 mg/dl. Yet, the decrease of fibrinogen concentration was also pronounced in these 3 patients: -82%, -67%, and -73%, respectively. Accelerated wound healing was observed in 9 of the 10 patients. In conclusion, affinity chromatography using the pentapeptide gly-pro-arg-pro-lys is an effective, selective and safe procedure to lower fibrinogen concentration in plasma thereby improving blood viscosity. It could be a therapeutic option in severe blood vessel disease where drug therapy is not sufficient and invasive procedures like bypass or angioplasty cannot be applied.

Background and indications for protein A-based extracorporeal immunoadsorption

Protein A (SPA), a major cell wall component of Staphylococcus aureus, has occupied numerous investigators from its discovery in the late fifties. Its availability and avid binding to human immunoglobulins have led to extensive usage for diagnostic and research purposes. Today, SPA-based extracorporeal immunoadsorption relies on two rather different systems, namely, SPA-silica (Prosorba), and SPA-Sepharose (Immunosorba). Both systems are approved by the Food and Drug Administration for the core indications of rheumatoid arthritis and idiopathic thrombocytopenic purpura (SPA-silica) or hemophilia with inhibitors (SPA-Sepharose). Off label indications include immune disorders with a conceivable connection between autoantibody titers and disease activity, like forms of glomerulonephritis, systemic lupus erythematodes, myasthenia, and the Guillain-Barré syndrome as well as alloantibody formation in the context of e.g., transplantation. This review summarizes historical developments and important properties of SPA. Indications for extracorporeal therapy are discussed on the basis of available information and personal experience.

Two Cases of Refractory Endocrine Ophthalmopathy Successfully Treated with Extracorporeal Immunoadsorption

Endocrine ophthalmopathy (EO) is a severe disease entity that is characterized by retrobulbar swelling due to accumulation of glycosaminoglycans on an autoimmune basis. This disorder can lead to the loss of vision and often is resistant to conventional therapy. There is a relation to Graves' hyperthyroidism, but probably no close association. Two patients with severe EO that was resistant to usual therapeutic approaches including steroids and radiological and surgical measures underwent a 20 session course of intensive immunoadsorption therapy (Plasmaselect/Therasorb Anti-IgG) with a mean 2- to 3-fold plasma volume treated. After the first sessions, both patients voiced an impressive relief of their major symptoms, which was confirmed by ophthalmological investigation. Throughout the time of therapy until present, these patients have remained at their respective levels of improvement. We consider immunoadsorption an effective therapeutic opportunity in severe EO resistant to conventional treatment.

Release of microparticles in LDL apheresis

Particle contamination of blood always takes place in extracorporeal systems and few studies have been conducted to evaluate potential risks. Particle concentration was measured in the efferent blood line on original equipment for two established LDL elimination procedures (DALI) (Fresenius) and Liposorber (Kaneka). Acquired data were compared with standards for infusion solutions from European (EP) and American (USP) Pharmacopoeia. All values were well below the given limits. Even in extreme situations (>20 pump stops) particle concentration did not exceed the standards. Considering an average treated blood volume of 7.31 for the DALI-System and 17.01 for Liposorber (long term clinical studies) the absolute amount of particles infused per treatment was 167,000 (DALI) and 465,000 (Liposorber) particles > or = 2 microm.

Three cases of C-ANCA-positive vasculitis treated with immunoadsorption: possible benefit in early treatment

Wegener's granulomatosis is a vasculitic disease predominantly affecting the upper respiratory tract, lungs, and kidneys. Three patients with Wegener's granulomatosis and rapidly progressive glomerulonephritis were treated with an intensified regimen of immunoadsorption (IA) (Excorim or Therasorb) in addition to cyclophosphamide (CYC) and methylprednisolone (PRE). Patient A had been in remission under oral CYC/PRE. The first exacerbation was treated successfully with 4 IA treatments without changing medication. Patient B experienced 3 flares within 1 year, which were treated with 28 IA (3-7 IAs/course), intravenous CYC after each course, and PRE. A fall of creatinine levels from 120 to 190 micromol/L to 100 micromol/L was noted after IA and before administration of CYC. Patient C presented in uremia. Autoantibodies were eliminated by 11 IA treatments parallel to CYC/PRE therapy. They remained within a normal range for >1 year's follow-up; however, kidney function did not return. In conclusion, the observations in Patients A and B suggest a beneficial therapeutic effect of early IA in WG.

The outcome in myasthenia gravis patients--an eight-year follow-up after finishing immunoabsorption therapy

Eight years ago four patients suffering from myasthenia gravis (MG) type C and E according to Compston with failed drug therapy were treated three times (one patient 11 times) by protein A immunoabsorption (Immunosorba, Excorim, Fresenius Hemocare GmbH, StWendel, Germany). No further immunoabsorption treatments have been carried out. In addition, three patients were given a thymectomy. The present status of the patients was checked six and eight years thereafter. We could see a beneficial effect in all MG patients. The patients are fit for work; all have an improved Besinger index. The patients were used as their own controls. A higher anti-AChR-ab level six years after protein A immunoabsorption than at the beginning was seen in all patients combined with a less serious MG. In addition, their immunomodulation could be induced as seen in lymphocyte and inflammatory protein changes during the first 36 days after beginning immunoabsorption treatment. A larger population has to be investigated to verify these results.

Extracorporeal removal of circulating immune complexes: from non-selective to patient-specific

The classical immune complex-mediated disease, termed serum sickness, developed a short time after the injection of horse anti-tetanus toxin. Antibodies against circulating horse plasma proteins lead to the formation of immune complexes within the blood circulation (CIC). The inflammatory response, including systemic complement activation and vasculitis, seriously affected the function of all organs, including the most susceptible kidney. Meanwhile CIC have been detected in almost every systemic disease, including autoimmune disorders and also cancer and infections. This brief review will focus on the rationale and the equipment for extracorporeal elimination of CIC.