Regular Hemoperfusion in Regular Dialysis Treatment. A Long-Term Study

The capacity of activated charcoal to remove toxins from the blood is well established. Its poor biocompatibility, inability to remove urea, electrolytes and water, and high cost have so far been the major objection to a wider use of charcoal with chronic uremic patients.

The availability of a charcoal coated by a new highly hydrophilic methacrylate based membrane enabled us to keep 18 uremic patients on a combined hemodialysis-hemoperfusion schedule for 4–52 weeks. Investigations concerned patients in whom relapsing signs of uremia occurred despite technically adequate dialysis, and other cases where dialysis was both technically and clinically adequate. In the first group of patients, the conbined programme led to an improvement of the dialysis resistent clinical signs, while certain positive metabolic effects were also observed. In the second group, the hemodialysis-hemoperfusion treatment allowed a reduction of about 30% in time of treatment per week.

Tolerance of the new coated charcoal was good throughout treatment in terms both of biocompatibility and of side effects.

Combined Hemodialysis-hemoperfusion Treatment Reduces the time of Substitutive Therapy in Chronic Uremia

Charcoal hemoperfusion has long been used in chronic uremia as an adjunct or substitute for conventional hemodialysis.

In this study a regular combination of hemoperfusion and hemodialysis was used to cut down the weekly substitutive sessions from 3 to 2. Ten RDT patients were treated with the reduced-time schedule for 5–56 weeks. Clinical and metabolic conditions remained stable in all patients and no sign of inadequate treatment appeared. Long-term charcoal hemoperfusion was confirmed to be a safe and risk-free procedure. No change in platelets, white cells, red cells, fibrinogen and other hematochemical parameters were detected.

Effects of Dialysis Membrane Nature on Intradialytic Phagocytizing Activity

Blood-membrane contact in the extracorporeal circuit affects the activation of many biological systems. Among these, phagocytizing activity has been reported to be influenced by the nature of the hemodialysis membrane used, whether cellulosic or synthetic.

This work reports on an ex-vivo, comparative test between cellulosics and synthetics concerning the effects of blood-membrane contact on the polymorphonucleate and monocyte phagocytizing function, both during and after the hemodialysis session.

By means of flow cytometry, we evaluated the capacity for phagosoma formation and oxidative burst both in polymorphonucleates and monocytes. Ten hemodialysis patients were included in the study. Six separate dialysis procedures for each patient were considered, one per dialyzer (3 cellulosic and 3 synthetic membranes). Tests were performed at 15', 60', 210’ and 4 hours after the session end. Comparative evaluation was made according to Student's t test.

Polymorphonucleate phagocytosis and oxidative burst activation were globally more marked for synthetic than cellulosic membranes, tending to level out in the post-dialysis. This result could be affected by their functional exhaustion following pulmonary sequestration. Monocyte intradialytic phagocytosis and oxidative burst proved more activated by cellulosic membrane. All differences tended to vanish in the post-dialysis.

Biocompatibility of Charcoal Hemoperfusion. Effects of Long-Term Treatment on Lymphocyte Characteristics and Function

Biocompatibility of charcoal hemoperfusion was studied in a group of 15 uremic patients, evaluating the effects of long-term treatment on some structural and functional parameters of circulating lymphocytes: in vivo distribution of T-cell subsets; surface T3, T4 and T8 antigen expression, in vivo and in vitro DNA synthesis. A comparative analysis was performed with patients on conventional dialysis using cuprophan membranes.

Severe Gastrointestinal Bleeding in a Uremic Patient Treated with Estrogen-Progesterone Therapy

Gastrointestinal bleeding is a frequent complication in hemodialysis patients; angiodysplasia is a potential cause, with a higher incidence in uremic patients. We describe a case of severe anemia (Hemoglobin up to 3.5 g/dl) secondary to diffuse angiodysplastic lesions in a hemodialysis patient with mixed connective tissue disease. The case is characterised both by the severity of the clinical picture (extension and entity of angiodysplastic lesions, frequency of bleeding episodes) and by the patient's religious faith which made her reject blood transfusions. We underline the efficacy of estrogen-progesterone therapy in view of the modest results obtained with other therapeutic strategies on bleeding.

Mathematical Modeling of Solute Kinetics and Body Fluid Changes during Profiled Hemodialysis

A mathematical model of solute kinetics oriented to improve hemodialysis treatment is presented. It includes a two-compartment description of the main solutes (K+, Na+, Cl–, urea, HCO–3, H+, CO2), acid-base equilibrium through two buffer systems (bicarbonate and non-carbonic buffers) and a three-compartment model of body fluids (plasma, interstitial and intracellular). The main model parameters can be individually assigned a priori, on the basis of body weight and plasma concentration values measured before beginning the session.

Model predictions are compared with clinical data obtained during 11 different hemodialysis sessions performed on six patients with profiled sodium concentration in the dialysate and profiled ultrafiltration rate. In all cases, the agreement between the time pattern of model solute concentrations in plasma and clinical data turns out fairly good as to urea, sodium, chloride and potassium kinetics. Finally, the time patterns of plasma bicarbonate concentration and pH can be reproduced fairly well with the model, provided CO2 concentration remains constant. Only in two sessions, blood volume was directly measured in the patient, and in both cases the agreement with model predictions was good.

In conclusion, the model allows a priori computation of the amount of sodium removed during hemodialysis, and may enable the prediction of plasma volume changes and plasma osmolarity changes induced by a given sodium concentration profile in the dialysate and by a given ultrafiltration profile. Hence, it can be used to improve the dialysis session taking the characteristics of individual patients into account, in order to minimize intradialytic imbalances (such as hypotension or disequilibrium syndrome).

Jugular Vein-Mammary Artery Fistula after Catheterism for Hemodialysis: Case Report

The demographic characteristics of hemodialysis (HD) patients increase the need for the tunneled cuffed permanent catheter (TCC) as a definitive vascular access (VA) for HD. The internal jugular vein is increasingly being used as a route for TCC or temporary catheter placement and can be associated with serious complications. Among them other authors have described arteriovenous fistula (AVF) creation between the common carotid artery and the right jugular vein. We describe a case of an AVF between the right internal jugular vein and the right internal mammary artery. The fistula was detected during the TCC placement in a patient who underwent several jugular and subclavian catheterisms for HD in her clinical history.

Fluidodynamic Evaluation of Arteriovenous Fistulae for Hemodialysis

Arteriovenous fistulae (AVF) are commonly used in dialysis treatment of uremic patients. However, many AVF create problems and have to be re-examined. Problems arise in the cannulation site and must be treated with antibiotics, and stenosis, both in the arterial and in the venous side of the AVF. In the worst case, the AVF must be replaced for treatment to continue. However, this can only be repeated once before the AVF site is no longer viable. This increases the discomfort, the morbidity and the mortality of the dialysis patient. Several kinds of AVF were studied to determine whether flow disturbances give rise to these complications. Many studies have already demonstrated the importance of hemodynamic factors in vascular disease pathogenesis. These factors include: the pulsatility of flow, the elasticity of the vessel, the non-Newtonian blood, flow behavior and, very importantly for AVF, the vessel geometry. In model studies, intimal changes have been observed in bends and bifurcations, regions of vessel construction and vessel stenosis. In these regions, blood flow changes abruptly and this contributes to arterial disease. We prepared several one-to-one, true-to-scale elastic silicon rubber models of different AVF. The AVF models were based on angiographic studies of chronic dialysis patients and on AVF from the arms of cadavers. The models had a similar compliance to that of the human blood vessel. Flow was visualized using photoelasticity apparatus and a birefringent blood-like fluid. This method is suitable to analyze the spatial configuration of flow profiles, to differentiate laminar flow from disturbed flow, and to visualize flow separation, vortex formation and secondary flow. It was found that AVF create disturbances that are not found under normal physiological flow conditions. The X-formed AVF was very unsatisfactory, creating significant flow disturbances. The AVF had high velocity fluctuations. These could lead, for example, to aneurysm formation. A better configuration would be an end-to-end AVF. However, this formation creates other complications. For example, there is not enough blood to the hand and parts of the hand lose feeling. The recommended AVF would be an end-to-side anastomosis. In this case, attention is needed for placement geometry, to minimize additional flow disturbances. Several models as well as patient angiographic studies are discussed.

Hemoperfusion in Reduced-Time Programmes for Chronic Uremia. Long-Term Results

This paper reports the Authors' 8 year experience in the clinical use of charcoal hemoperfusion as a means to reduce the weekly time of treatment in chronic uremic patients. Two different programmes were applied. Programme A (34 patients) which involved substituting the 3 procedures per week of standard dialysis (4 hours duration each) by 2 procedures of combined hemodialysis and hemoperfusion, again of 4 hours duration each. Programme B (18 patients) which involved substituting the 3 procedures per week of 4 hours duration by 3 procedures of 3 hours each, 2 of combined hemodialysis and hemoperfusion, 1 of conventional dialysis. The net weekly reduction was 33% for Programme A and 25% for Programme B. The efficacy of the two Programmes was evaluated by clinical, hematochemical, nutritional and instrumental parameters.

Hemoperfusion with a New Anion Exchange Resin Corrects the Metabolic Alkalosis in Pyloric Stenosis: An Experimental Demonstration

An experimental model of hypertrophic pyloric stenosis was made by suture of the pyloric wall and gastrostomy in 10 rabbits under general anesthesia. Blood sampling indicated severe alkalosis and hypochloremia 3h 30 min after surgery. To correct the derangement, we tested an ion exchange resin (Dowex SAR), coated with a methacrylic hydrogel. A cartridge containing 18 g of this resin was inserted in an extracorporeal circuit. This chloride charged resin achieved uptake of HCO−3 ions, and elution of CI− ions. The electrolytic balance was fully restored after 10 min of treatment.

Evidence of Profiled Hemodialysis Efficacy in the Treatment of Intradialytic Hypotension

In the last 10 years the percentage of dialysis patients suffering from clinical intradialytic intolerance has greatly increased.

Profiled hemodialysis (PHD) is a new technical approach, alternative to standard hemodialysis (SHD) for the treatment of intradialytic symptomatic hypotension. It is based on intradialytic modulation of the dialysate sodium concentration, using a dialysate sodium concentration profile elaborated by a new mathematical kinetic model.

The aim of PHD is to reduce the intradialytic blood volume decrease, thanks to a dialysate sodium profile, which allows a reduction in the plasma osmolarity decrease, thereby boosting intravascular fluid refilling.

This work aims at clinically validating the PHD technique, by testing its ability, against SHD, to maintain a more stable intradialytic blood volume; this evaluation was supported by monitoring some hemodynamic parameters.

Twelve dialysis patients on SHD treatment were selected because of their intradialytic symptomatic hypotension. Twelve SHD (one per patient) and 12 PHD sessions (one per patient) were performed to achieve the same sodium mass removal and body weight decrease on both PHD and SHD. During these sessions we monitored the blood volume variation % by the critline (a non invasive blood volume monitoring device), the mean blood pressure and heart rate directly and, finally, the stroke volume and cardiac output indirectly by bidimensional doppler-echocardiography.

Comparison of the results obtained with the two techniques shows PHD to achieve a significantly more stable blood volume, blood pressure and cardiovascular function than SHD, in particular during the second and the third hour of the dialysis session.

An Algorithm for the Rational Choice of Sodium Profile during Hemodialysis

The incidence of intradialytic disequilibrium syndrome and symptomatic hypotension has increased significantly among dialysis patients over the last ten years. Profiled hemodialysis (PHD) is a new technique, based on the intradialytic modulation of dialysate sodium concentration, which aspires to reduce to previous imbalances.

This paper presents a new algorithm for the determination of a rational dialysate sodium profile during PHD. A mathematical model of solute kinetics, monocompartmental for sodium and bicompartmental for urea is used. The algorithm allows the sodium profile to be elaborated a priori before each dialysis session, respecting the individual sodium mass removal and weight gain. A procedure allowing the adjustment of the method to the individual characteristics, on the basis of routine measurements performed before each session is also presented.

The method was validated during seven dialysis sessions. Comparison between data measured in vivo and those predicted by the model showed standard deviations corresponding to the range of laboratory measurement errors: 1.50 mEq/L for sodium and 0.87 mmol/L for urea. In vivo implementation of PHD by our algorithm allows one to remove an amount of sodium close to that established a priori on the basis of patient's need.

Fibroblast proliferation over dialysis membrane: an experimental model for “tissue” biocompatibility evaluation

The present study reports on a biological model based on fibroblast proliferation applied to 3 different types of flat-plate dialysis membrane, in order to ascertain whether the artificial materials currently used in hemodialysis cause in vitro cellular proliferation. The study plan we followed involved plate membrane isolation from non-used dialyzers and used dialyzers, observed through scanning electron microscopy (SEM) both before and after testing with human fibroblasts by means of cell culture. Fibroblast growth was assessed by phase contrast light microscopy examination and cytometric DNA content evaluation. Our investigations proved that the artificial materials we considered interact with fibroblast cultures. Noticeable proliferative response was observed both after contact with unused material and on mediation by the protein layer absorbed on the membrane surface at the end of dialysis sessions. In this last case fibroblast proliferative activity appeared higher than that observed with unused membranes, showing that the soluble molecules entrapped in the protein layer appeared able to exert a biological activity even in in vitro tests

Effect of Different Dialysis Membranes on Platelet Function. A Tool for Biocompatibility Evaluation

Intradialytic coagulative and platelet activation, one of the main consequences of blood-membrane contact, was studied in a group of 5 RDT patients with a comparative evaluation of 3 different dialytic membranes: Cuprophan (CU), Polysulfone (PS) and Cellulose Triacetate (CT). Each patient underwent 5 consecutive dialysis sessions with the above mentioned membranes. Intradialytic platelet activation was studied through a morpho-functional evaluation between the mean platelet volume (MPV) and Serotonin (S), ß-Thromboglobulin (ß-TG) and Platelet Factor 4 (PF4) serum levels. These determinations were made before HD (time 0) and after 30', 120’ and 240'. We also checked the intradialytic status of thrombogenesis and fibrinolysis determining aPTT, thrombin time, fibrinogen, antithrombin III (AT III), α-2 antiplasmin and plasminogen, at the same time intervals. All membranes tested (CU, PS, CT) caused appreciable intradialytic platelet activation, above all after 15’ and at the end of dialysis sessions, more marked for CU than PS or CT. In particular MPV showed a decrease throughout the session (-5% at 30’ and -9% at 240') while S, ßTG and PF4 peripheral blood levels showed a significant increase at the same intervals with CU membrane. Lastly coagulative and fibrinolytic parameters showed no significant differences among any of the membranes tested.

A Simple Mathematical Model of Intradialytic Sodium Kinetics: “in vivo” Validation During Hemodialysis with Constant or Variable Sodium

A simple mathematical model of the intradialytic relationship between natraemia and dialysate sodium concentration is presented. The model includes a bicompartmental description of sodium, urea and fluid kinetics and an algebraic characterization of diffusive/convective mass-transfer across the dialysis membrane. Its ability to provide realistic responses has been validated comparing model predictions by a priori parameter tuning against quantities measured during in vivo sessions with both constant and variable dialysate sodium concentration. A quantitative analysis of model predictions indicates that the mean deviation between data calculated by the model and those measured in vivo is 1.32 mEq/l for sodium and 0.76 mmol/l for urea, values which do not greatly exceed the measurement errors of current instruments. The model's predictive capacity thus proves reliable. The ability of the model to calculate the amount of sodium removed and the time course of intra-extracellular volumes during the dialysis session makes it possible to forecast the patient's clinical tolerance to a given sodium dialysate concentration.

The First Case of Ureteral Duplication in a Combined Liver-Kidney Transplantation

Aim

Kidney transplantation with ureteral duplication may represent a doubled risk factor in terms of ureteral stenosis or necrosis with urinary leakage usually from the site of ureteroneocystostomy. The incidence of complete duplication is very low at 0.19%. We report a kidney with ureteral duplication in the specific setting of multiorgan transplantation since it could be considered a adjunctive risk factor for urological complications.

Methods

The recipient was a 67-year old man, suffering from terminal renal insufficiency. He was also affected by HCV-related cirrhosis. The patient had been waiting for the combined transplantation for 27 months and in the last two months his hepatic function dramatically worsened. The donor was a 53-year old man who died of non-traumatic subarachnoid hemorrhage. Good HLA compatibility was observed between donor and recipient. During harvest both kidneys presented a complete ureteral duplication. So the ureters were freed together with a wide cuff of periureteral tissue and dissected distally. No vascular abnormalities were noted during the removal of either kidney. The grafts were flushed with University of Wisconsin solution and stored in the same solution.

Results

The liver was reperfused after 9 hours of cold ischemia. Subsequently the kidney was vascularized after 15 hours of cold ischemia. Urine production occurred immediately after revascularization. Two separated ureteroneocystostomies with a single antireflux technique were performed. Cyclosporine and steroids were given. Post-operative course was uneventful and liver and kidney function were normal. The 7-day cystography was normal. The 6, 12, 24 month ultrasonographies showed no signs of hydronephrosis or hydroureter. After 28 months renal cancer was diagnosed and the patient underwent a right nephrectomy. The liver-kidney recipient had excellent hepatic and renal function for 84.7 months. He died of malignancy from de novo tumor.

Conclusions

On the basis of this experience, a kidney with an ureteral duplication, while rare, can be satisfactorily used also in combined liver-kidney transplantation.

Clinical Application of Sodium Profiling in the Treatment of Intradialytic Hypotension

Background

Intradialytic hypotension is mainly induced by the removal of extracellular sodium during dialysis, which impairs intravascular fluid refilling and reduces blood volume. To counter this complication we tested a new kind of profiled hemodialysis (PHD) consisting of the intradialytic modulation of dialysate sodium concentration according to individual profiles set up using a new mathematical model for intradialytic solutes and water kinetics. The clinical aim of this PHD is to stabilize blood pressure maintaining higher blood volume values than standard dialysis treatments. We clinically validated PHD in comparison with constant dialysate sodium dialysis (CHD).

Methods

Twenty hypotensive dialysis patients underwent one PHD and one CHD session maintaining the same dialysis length, sodium mass removal and body weight decrease. A new mathematical model was used to define both the dialysate sodium profiles for PHD and the constant dialysate sodium for CHD. Percent blood volume variation (Crit-line), mean blood pressure, heart rate, cardiac output (Doppler-echocardiography) were monitored intradialitically.

Results

Cardiovascular stability improved on PHD as compared with CHD sessions; blood volume and cardiac output during PHD showed a lower decrease than on CHD, the differences statistically significant (from 30' and 60' respectively). Mean blood pressure was, at all time intervals, more stable on PHD than on CHD and was accompanied, on PHD, by a lower heart rate increase (differences statistically significant).

Conclusions

This study shows that PHD performed using dialysate sodium profiles elaborated by our mathematical model obtains, in hypotensive patients, a higher hemodynamic intradialytic stability than CHD, probably due to a higher stabilization of blood volume.

Is β2-Microglobulin-Related Amyloidosis of Hemodialysis Patients a Multifactorial Disease? a New Pathogenetic Approach

Purpose

β2-microglobulin amyloidosis (Aβ2M) is one of the main long-term complications of dialysis treatment. The incidence and the onset of Aβ2M has been related to membrane composition and/or dialysis technique, with non-homogeneous results. This study was carried out to detect: i) the incidence of bone cysts and CTS from Aβ2M; ii) the difference in Aβ2M onset between cellulosic and synthetic membranes; iii) other risk factors besides the membrane.

Methods

480 HD patients were selected between 1986 to 2005 and grouped according to the 4 types of membranes used (cellulose, synthetically modified cellulose, synthetic low-flux, synthetic high-flux). The patients were analyzed before and after 1995, when the reverse osmosis treatment for dialysis water was started at our center, and the incidence of Aβ2M was compared between the two periods. Routine plain radiography, computer tomography (CT) and nuclear magnetic resonance imaging (MRI) as well as electromyography were used to investigate the clinical symptoms.

Results

Bone cysts occurred in 29.2% of patients before 1995 vs. 12.2% after 1995 (p<0.0001). CTS occurred in 24% of patients before 1995 vs. 7.1% after 1995 (p<0.0001). Bone cysts and CTS occurred in older patients, who began dialysis at a late age, with high CRP, low albumin, low residual GFR, and low Hb. Cox regression analysis showed that the risk factor for bone cysts was high CRP (RR 1.3, p<0.01), while albumin (RR 0.14, p<0.0001) and residual GFR (RR 0.81, p<0.0001) were revealed to be protective factors. Cox analysis for CTS confirmed CRP as a risk factor (RR 1.2, p<0.01), and albumin (RR 0.59, p<0.0001) and residual GFR (RR 0.75, p<0.0001) as protective factors. The comparison obtained between membranes did not suggest any protective effect on Aβ2M.

Conclusions

The findings that the inflammatory status as well as low albumin and the residual GFR of the uremic patient are predictive of Aβ2M lesions suggests that Aβ2M has a multifactorial origin rather than being solely a membrane- or technique-related side effect.

Physical activity in solid organ transplant recipients: organizational aspects and preliminary results of the Italian project

Most of the difficulties when trying to realize the proposal to prescribe physical activity for transplantation patients come from patient attitudes and cultural beliefs that ignore the benefits of exercise, but there also are organizational aspects arising from the difficulties that these patients face in accessing supervised exercise facilities. To address these difficulties, the Italian study project "Transplant … and Now Sport" was developed based on a model of cooperation among transplantation specialists, sports physicians, and exercise specialists organized as a team combining their specific skills to effectively actuate the physical exercise programs. This preliminary report is based on 26 patients (16 male, 10 female; 47.8±10.0 years old; 21 kidney and 5 liver transplantations; time from transplantation 2.3±1.4 years) who performed prescribed and supervised exercises consisting of 3 sessions per week of aerobic and strengthening exercises for 1 year. Preliminary results show a significant decrease in body mass index (t=1.966; P<.05) and a significant increase in peak aerobic power (t=4.535; P<.01) and maximum workload (t=4.665; P<.01) on the incremental cycling test. Also maximum strength of knee extensors (t=2.933; P<.05) and elbow flexors (t=2.450; P<.05) and countermovement jump performance (t=2.303; P<.05) significantly increased. Creatinine and proteinuria tended to decrease, but the differences were not significant. In health-related quality of life assessed by the SF-36 questionnaire, the Bodily Pain, General Health, Vitality, Social Functioning, and Role Emotional scale scores showed a significant improvement (P<.05). Preliminary results of the study protocol "Transplant…and Now Sport" show the positive effects of the model based on cooperation among transplantation centers, sports medicine centers, and gyms in the administration of a supervised exercise prescription. These data should be considered a contribution to developing and promoting further detailed exercise protocols and to fostering improved posttransplantation health and survival, helping to ensure that physical activity becomes a safe routine medical treatment plan of patient management.

Donor-specific anti-HLA antibodies after bone-graft transplantation. Impact on a subsequent renal transplantation: a case report

Immunological evaluation by panel-reactive antibody (PRA) and determination of anti-HLA specificity are important phases in the evaluation of patients awaiting kidney transplantation. The main causes of immunization are previous solid organ transplantation, hemotransfusion, and pregnancy. It is also possible that immunogenicity can be triggered by vascularized tissue grafts. Immune induction by cryopreserved bone prostheses is not yet understood. A 19-year-old patient with osteosarcoma had undergone resection of the left proximal tibia with reconstruction using human bone in 1997. The donor HLA typing was as follows: A3, A29 (19); B44 (12), Bw4; DR13 (6), DR7, DR52, DR53. The patient was subsequently enrolled onto the waiting list for cadaveric donor kidney transplantation due to chronic kidney failure caused by cisplatin toxicity. Pretransplantation immunological screening using the complement-dependent cytotoxicity (CDC) technique revealed a PRA of 63%. IgG antibody specificities were detected against class I and class II donor antigens, specifically anti-A3, B44, DR7 antibodies, using flow cytometry (Tepnel Luminex). Further immunological studies using single HLA specificity analysis (LSA Class I degrees -II degrees , Tepnel-Luminex) showed direct antibodies against all donor antigen specificities. This case showed immune induction after the implantation of bone prosthesis in a kidney transplant candidate, underlining the importance of the availability of HLA typing data of donors of a human prosthesis.

Multicentric experience with combined hemodialysis/hemoperfusion in chronic uremia

A multicentric study was carried out to investigate the safety and effectiveness of long-term treatment of chronic uremic patients by a regular combination of hemodialysis and charcoal hemoperfusion. 39 RDT patients from five dialysis centers were treated for up to 12 months. The combined treatment proved to be safe, well tolerated and effective in improving certain dialysis-resistant uremic signs, mainly severe peripheral neuropathy, asthenia, anorexia, nausea, lack of well-being and relapsing pericarditis. There was also a marked decrease, after several weeks of combined treatment, in plasma values of urea, uric acid and creatinine.

Use of combined hemodialysis/hemoperfusion in chronic uremia

The capacity of charcoal to absorb endogenous and exogenous toxins is well established. It removes substances of higher molecular weight than standard dialysis membranes. The regular use of charcoal hemoperfusion as an adjunct to hemodialysis in chronic uremia is a real prospect capable of improving the patient's clinical and laboratory condition and/or reducing the weekly time of treatment. In line with our previous experience, 5 consenting informed patients on regular dialysis treatment from 9 to 35 months (residual creatinine clearance 0-1.8 ml/min, mean diuresis 350 ml) were treated without interruption for 5-8 months according to a schedule including two combined hemodialysis/hemoperfusion procedures instead of the previous three hemodialysis sessions. Patients were on adequate dialysis and their clinical, metabolic and laboratory conditions were stable. In the hemodialysis/hemoperfusion procedure a cartridge containing 150 g of methacrylate-coated activated charcoal with high biocompatibility was inserted in the dialysis circuit in series with a flat plate or hollow fiber dialyzer. Clinical, laboratory and metabolic conditions remained unchanged in all patients despite the one third reduction in dialysis hours per week. The tolerance of treatment was good: platelets, white cells and fibrinogen were unaffected. The marked reduction in weekly time of treatment led to a more satisfactory personal and social rehabilitation, enabling more patients to be treated with the same facilities.

The Kidney Donor Profile Index (KDPI) of marginal donors allocated by standardized pretransplant donor biopsy assessment: distribution and association with graft outcomes

Pretransplant donor biopsy (PTDB)-based marginal donor allocation systems to single or dual renal transplantation could increase the use of organs with Kidney Donor Profile Index (KDPI) in the highest range (e.g. >80 or >90), whose discard rate approximates 50% in the United States. To test this hypothesis, we retrospectively calculated the KDPI and analyzed the outcomes of 442 marginal kidney transplants (340 single transplants: 278 with a PTDB Remuzzi score<4 [median KDPI: 87; interquartile range (IQR): 78-94] and 62 with a score=4 [median KDPI: 87; IQR: 76-93]; 102 dual transplants [median KDPI: 93; IQR: 86-96]) and 248 single standard transplant controls (median KDPI: 36; IQR: 18-51). PTDB-based allocation of marginal grafts led to a limited discard rate of 15% for kidneys with KDPI of 80-90 and of 37% for kidneys with a KDPI of 91-100. Although 1-year estimated GFRs were significantly lower in recipients of marginal kidneys (-9.3, -17.9 and -18.8 mL/min, for dual transplants, single kidneys with PTDB score<4 and =4, respectively; p<0.001), graft survival (median follow-up 3.3 years) was similar between marginal and standard kidney transplants (hazard ratio: 1.20 [95% confidence interval: 0.80-1.79; p=0.38]). In conclusion, PTDB-based allocation allows the safe transplantation of kidneys with KDPI in the highest range that may otherwise be discarded.

Induction therapy with alemtuzumab (campath) in combined liver-kidney transplantation: University of Bologna experience

BACKGROUND

Combined liver-kidney transplantation (LKT) is considered to be a safe procedure, but the appropriate immunosuppressive regimen is unclear.

PATIENTS AND METHODS

Between January 1997 and October 2011, 55 patients were listed for LKT: 45 (82%) were effectively transplanted, 5 (9.2%) died whereon here the waiting list, 3 (5.5%) temporarily out of waiting list, 1 (1.8%) was on waiting list and 1 (1.8%) refused LKT. Five LKTs treated with cyclosporine (CyA) were excluded from the analysis. Mean recipient age was 50.32 ± 10.32 years (14-65), MELD score at time of LKT was 19.22 ± 4.69 (8-29), mean waiting list time was 8.14 ± 9.50 months (0.1-35.76), and follow-up, 4.09 ± 3.02 years (0.01-10.41). Main indications for LKT were policystic disease (n = 15; 37%), hepatitis virus C (HCV)-related cirrhosis (n = 9; 22%) metabolic disease (n = 5; 13%), hepatitis virus B (HBV) cirrhosis (n = 4; 10%), alcoholic cirrhosis (n = 4; 10%), and cholestatic disease (n = 3; 8%). Immunosuppressive regimen was based on tacrolimus and steroids in 40 cases with induction therapy with alemtuzumab (Campath; 0.3 mg/kg) in 13 of 40 instances cases administered on day 0 and day 7.

RESULTS

Postoperative mortality was 2.5%. Acute cellular rejection episodes were biopsy-proven in 2 (5%) cases, post-LKT infections developed in 17 cases (42.5%), and de novo cancer developed in 3 (7.5%) cases. Similar 5-year overall survivals were obtained irrespective of the LKT indication: 100% in cholestatic and alcoholic cirrhosis patients, 86% in policystic disease, 75% in metabolic disease and HBV patients, and 66% in HCV cirrhosis. Overall survivals for the alemtuzumab vs without-induction therapy groups at 1, 3, and 5-years were 100%, 85.7%, and 85.7% vs 76%, 76%, and 70%, respectively (P = .04).

CONCLUSION

An immunosuppressive regimen based on tacrolimus and steroids with induction therapy with alemtuzumab was safe, with excellent long-term results for combined LKT.

The desorption process of macromolecules adsorbed on interfaces: the force spectroscopy approach

They're flexible and sticky: While investigations of the very stiff DNA molecular conformation on surfaces have been made, the equivalent for more typical macromolecules is complicated by their shorter persistance length. A gentle detachment study with a polymer bound to an SFM tip allows the forces between the polymer and surface to be probed; the detachement force required depends on the surface conformation, whether only a small loop or a long tail must be peeled from the surface, as shown by the cartoon.

Family recurrence and oligo-anuria predict uremic restless legs syndrome

OBJECTIVES

To determine clinical and laboratory predictors of restless legs syndrome (RLS) in patients with end-stage kidney disease (ESKD) undergoing long-term hemodialysis (HD).

MATERIALS AND METHODS

One hundred and sixty-two consecutive patients were assessed. History of sleep disturbances, neurological examination, clinical, and laboratory data were collected. Patients with and without RLS were compared, and a logistic regression model described the relations between independent predictors and RLS.

RESULTS

Fifty-one patients (32%) currently had RLS (RLS+). RLS+ vs RLS- patients were more frequently women (49% vs 29%, P = 0.012), had first-degree relative with RLS (22% vs 6%, P = 0.004), insomnia (59% vs 36%, P = 0.007), peripheral neuropathy (41% vs 21%, P = 0.006), and low residual diuresis (92% vs 68% with below 500 ml/24 h, P = 0.001). Low (OR = 8.71, CI = 2.27-33.41; P = 0.002) and absent (OR = 4.96, CI = 1.52-16.20; P = 0.008) residual diuresis, peripheral neuropathy (OR = 4.00, CI = 1.44-11.14; P = 0.008), and first-degree relative with RLS (OR = 3.82, CI = 1.21-12.13; P = 0.023) significantly predicted RLS in ESKD patients undergoing HD.

CONCLUSION

Positive family history for RLS together with reduced/absent residual renal function and peripheral neuropathy predicts the risk for RLS in ESKD patients undergoing HD. Longitudinal studies are warranted to correlate RLS occurrence with genetic and environmental factors.

Incidence of cancer in kidney transplantation waiting list patients: a single center experience

INTRODUCTION

It is widely accepted that the risk of malignancies is significantly increased among patients with end-stage kidney disease (ESKD) and after kidney transplantation compared with the general population. Only a few data are available on kidney transplantation waiting list patients. The aim of this study was to investigate solid organ cancer incidence among subjects on the waiting list at a single center.

MATERIALS AND METHODS

We retrospectively reviewed the records of all patients enrolled on our kidney transplantation waiting list between August 1, 2008 and July 31, 2010, seeking to evaluate the causes of withdrawal from the list, incidence of cancer, type of neoplasm, and its correlation with clinical features. We estimated the ratio of observed to expected numbers of cancers, the standardized incidence ratio (SIR).

RESULTS

Among 1184 patients, we excluded 569 patients from the waiting list including 26 (4.56%) who displayed malignancies. The overall incidence of cancer was 0.11 events/person-months and the overall prevalence of cancer was 2.2%. In 97% of patients, the malignant disease was confined to the primitive organ of origin without secondary dissemination. We observed a prevalence of cancers related to ESKD (17; 65.38%). The SIR for all cancer types in our population compared with the general population was 2.22. The SIR for native kidney and thyroid cancers among our population compared with the general population was >10.

CONCLUSION

The incidence of cancer was significantly increased among kidney transplantation waiting list patients compared with the general population. Our study highlighted the importance of a careful, targeted neoplastic screening. It could be particularly important for ESKD-related malignancies like native kidney tumors or thyroid cancers.

Physical performance in kidney transplanted patients: a study on desert trekking

Physical performance of kidney transplanted patients in challenging environments, such as deserts, has been poorly studied. Six kidney transplanted (T: 5 males, 1 female; 45±6 yrs) and 8 control (C: 5 males, 3 females; 49±13 yrs) subjects participated in a 5-day desert trek. Blood pressure, hydration status (Height2/Rz by bioimpedance), heart rate, energy expenditure (by SenseWear Pro Armband) and walking velocities were recorded during each daily trekking stage (GPS-assisted wearable devices). Systo-diastolic blood pressure did not differ between C (119/77±12/8 mmHg) and T (121/77±10/6 mmHg) groups throughout the study. The hydration status was stable from day 1 (Ht2/Rz: 64±13 cm2/Ohm in T and 59±12 cm2/Ohm in C subjects) to day 5 (66±11 cm2/Ohm in T and 61±13 cm2/Ohm in C subjects) in both groups. Two patients on steroid treatment showed a relative hyperhydration. Mean heart rate did not differ between T (135±10 bpm) and C (136±5 bpm) subjects throughout the study, although a reduction from day 1 to day 5 was observed in T subjects only (p<0.05 vs C group). No differences were found between T and C group in walking velocity (1.7±0.6 km/h in T and 1.7±0.5 km/h in C group); mean intensity of physical activity was 3.4±0.5 METs in T and 3.3±0.6 METs in C group during each trekking stage. Negligible differences were observed in cardiovascular, metabolic and hydration status adaptations to desert trekking between selected T and C individuals. T subjects with creatinine clearance > 55 ml/min showed acceptable physical performance and acclimatization to desert environment, suggesting a good long-term outcome of transplantation.

Alpine skiing and anaerobic performance in solid organ transplant recipients

Limited information has been published about sporting activities in solid organ transplant recipients. The aim of this study was to assess "in the field" performance capacities of a group of transplant recipients involved in an alpine skiing competition. We studied 16 transplant recipients (13 men and 3 women) who had undergone transplantations (11 kidney, 4 liver, and 1 heart) at 89 +/- 68 months prior while participating in an alpine skiing race. The patients performed a countermovement jumping test to measure the explosive power of the lower limbs. In all patients blood lactate concentrations (La) were measured at the end of a giant slalom race. The maximum displacement of the center of mass during the jumping test was 22.4 +/- 9.3 cm; the time to complete the giant slalom was 75.5 +/- 16.5 seconds and La was 3.5 +/- 0.8 mmol/L. We observed significant linear relationships between race time and La (R(2) = 0.4733; P < .01) and between race time and performance in the jumping test (R(2) = 0.3655; P < .05). This study indicated that recovery of anaerobic and technical sporting activities is possible in organ transplant recipients. Muscular power and anaerobic performances among a selected group of solid organ transplant recipients were similar to those of the general untrained population.

Native kidney function after renal transplantation combined with other solid organs in preemptive patients

Kidney transplantations combined with other solid organs are progressively increasing in number. There are no guidelines regarding the nephrologic indications for combined transplantations, namely liver-kidney (LKT), or heart-kidney (HKT), in preemptive patients with chronic kidney failure who are not on regular dialysis therapy. The objective of this study was to assess the functional contribution of the native kidneys after preemptive kidney transplantation combined with other solid organs. From 2004, 9 patients (aged 50.3 +/- 8.5 years) with chronic kidney failure (creatinine 2.5 +/- 1.0 mg/dL) caused by polycystic kidney disease (n = 4), vascular nephropathy (n = 2), interstitial nephropathy (n = 1), glomerulonephritis (n = 1), or end-stage kidney disease (n = 1), underwent combined transplantations (8 LKT, 1 HKT). A scintigraphic functional study (Tc-99DMSA or Tc-99mMAG3), was performed at 4 +/- 3 months after transplantation to evaluate the functional contribution of both the native kidneys and the graft. All patients were given immunosuppressive drugs, including a calcineurin inhibitor (tacrolimus/or cyclosporine). At the time of scintigraphy, renal function in all patients was 1.3 +/- 0.3 mg/dL. The functional contribution of the transplanted kidneys was on average 77 +/- 18%. Only in 1 patient was the contribution of the graft <50%. At follow-up after 36 months, patient and kidney survivals were 100%. The study confirmed a high risk of loss of native kidney function in the presence of organic nephropathy. In light of our experience, a creatinine clearance <30 mL/min in an appropriate cutoff for a combined transplantation. Close clinical and instrumental assessment pretransplant is essential before proceeding with a combined transplant program to exclude functional forms and to optimize the use of organs.