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La dialisi peritoneale ha disatteso le aspettative dei nefrologi e di quella parte dell'industria che tanto ha investito in questo campo. Dopo 40 anni di studi, l'evidenza principale è stata quella della scarsa biocompatibilità della DP e dell'inaspettata potente reazione di difesa del peritoneo, che cerca in tutti i modi di difendersi da quella che ritiene una vera e propria aggressione esterna. Anche se molto è stato fatto per rendere più accettabile il trattamento, questo è ancora oggetto di frequenti complicazioni, che devono indirizzare il nefrologo a impiegare la DP solo dove esistono indicazioni assolute o controindicazioni alla dialisi extracorporea, tralasciando, per ora, la DP come trattamento di prima scelta.

Peritoneal dialysis (PD) failed to meet the expectations not only of nephrologists but also of those companies that invested so much in this field. After 40 years of studies, the main evidences show the little biocompatibility of PD and the unexpected strong reaction of the peritoneum, which tries in every way to defend itself against what it considers an external aggression. Although much has been done to make PD more easily acceptable, this procedure implies a number of frequent complications that urge the nephrologist to use PD only when there are absolute indications for intracorporeal treatment or contraindications to extracorporeal dialysis, thus excluding, for the moment, PD as a treatment of first choice.

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Objective Peritoneal catheters often become dislocated, and this may lead to malfunction. Since it is not usually possible to bring them back into their correct position, they must be replaced. With the aim of preventing this complication, we designed a new catheter. Design The new catheter has the same form as the Tenckhoff catheter except for a small increase in external diameter of the last 2 cm, made possible by the high specific weight of a small12-g tungsten cylinder incorporated in the Silasticat the abdominal end. The new catheter may be inserted by a percutaneous technique. Setting University hospitals of Sienaand Perugia, Italy. Patients In the last three years, 32 of these catheters have been implanted for a total experience of 468 patientmonths. Their position was checked on insertion and every two months thereafter by radiography; 26 Tenckhoff catheters (415 patient-months) were studied at the same time. Insertion was performed surgically and by a percutaneous method. The frequency of cuff extrusion, exit-site infections, leakage, and peritoneal infection were noted, together with peritoneal function, which was evaluated by KTN and weekly creatinine clearance one month after catheter insertion; the tests were repeated when dislocation occurred and at the end of the trial. Results No dislocations occurred with the self-locating catheters, whereas nine dislocations occurred in control patients (p = 0.0003). There were no significant differences with respect to controls for cuff extrusion, exit-site infections, leakage, peritoneal infection, and peritoneal function. Conclusions The presence of a small weight at the catheter tip prevents displacement completely, keeping the intraperitoneal part of the catheter in place.

The history of the various connection systems proposed and tried during the first 15 years of clinlcal application of continuous ambulatory peritoneal dialysis (CAPD) is reviewed. In order to understand the reasons for their success or lack of success, the main technical and operating characteristics regarding their efficacy In preventing peritonitis are examined in detail, together with a range of other pros and cons (I.e., reliability, simplicity, ease of use, cost, aesthetlcal aspects). The result Is an updated state-of-the-art review In the field of CAPD connectology, with a look at future trends.

Summary A major cause of morbidity for haemodialysis patients is vascular access failure and/or occlusion. It is commonly believed that increased frequency of dialysis sessions, among other factors, might lead to higher rates of fistula complications. To evaluate if patients on daily haemodialysis carry a higher risk of vascular access occlusion, we examined the raw incidence rate of access occlusion and the survival function of native vascular access in patients undergoing daily dialysis (DD - N. =24) as compared to patients on standard three times a week haemodialysis (TWD-N. =198). The number of thrombotic events in the first group was 2 (8%) whereas in the second group we observed 76 (38%) access problems (8%) (p

Human and rabbit peritoneal mesothelial cells have been successfully cultured and autoimplanted. An original biopsy technique was used to take samples of peritoneal mesothelial cells and after culture they were characterized from the structural and caryological points of view. Staphylococcal peritonitis was induced in 12 rabbits with indwelling peritoneal catheters and after 4 days of antibiotics 6 of them were autoimplanted with cultured autologous mesothelial cells previously marked in 3 cases with thymidine (H3TdR). Direct morphological observation and autoradiography were used to compare the mesothelium of control rabbits and implanted rabbits sacrificed on days 3 and 6 and showed that the cell implants had taken. Four uremic CAPD patients recovering from severe peritonitis were implanted with about 300 million autologous peritoneal mesothelial cells, previously cultured and frozen. Morphological signs of taking were evident from peritoneal laparoscopy biopsies performed 3 and 6 days after implant. The aim of the study was merely to demonstrate that such implants are possible; however, the techniques may have interesting applications not only in peritoneal dialysis, but also in the vaster fields of medicine and surgery.

In this randomized trial renal transplant recipients were treated with basiliximab, everolimus 3 mg/day, low-dose CsA. At transplantation, patients were randomized to stop steroids at the seventh day (group A) or to continue oral steroids in low doses (group B). Of the 113 patients enrolled, 65 were randomized to group A and 68 to group B. All patients were followed for 2 years. During the study 28 (43%) group A patients required reintroduced corticosteroids. One patient died, in group B. The Graft survival rate was 97% in group A and 90% in group B. There were more biopsy-proven rejections in group A (32% vs 16%; P = .044). The mean creatinine clearance was 54 +/- 21 mL/min in group A vs 56 +/- 22 mL/min in group B. Mean levels of serum cholesterol tended to be lower in group A, but the difference was of borderline significance (191 +/- 91 vs 251 +/- 188 mg/dL; P = .07). Vascular thrombosis (0 vs 5) and pneumonia requiring hospitalization (2 vs 7) tended to be more frequent in group B. Only three cases of CMV infection (1 vs 2) occurred. An immunosuppressive therapy with everolimus and low-dose CsA allows one to obtain excellent renal graft survival and stable graft function at 2 years. Early interruption of steroids in patients treated with this regimen may increase the risk of acute rejection, but neither affects graft survival nor graft function, while possibly reducing the risk of hyperlipemia and vascular thrombosis. About 60% of patients given everolimus and low-dose CsA can definitively stop steroids after 1 week.

Advanced glycation end products (AGE) accumulate in uremia and represent an important etiopathogenetic cause of morbidity in dialyzed patients. Conventional hemodialysis treatment seems to be ineffective in lowering AGE levels. We wished to investigate whether daily hemodialysis (DHD), a treatment that seems to result in better clinical condition in end-stage renal disease patients, is effective in the reduction of these compounds.We evaluated 10 non-diabetic patients on standard hemodialysis (SHD = 3 x 4 h/week) for more than 6 months by a crossover study. These patients were assigned randomly to 6 months of DHD (6 x 2 h/week) or 6 months of SHD. Then, they were switched to 6 months of the alternative treatment. At the end of these two periods, we studied pentosidine-like AGE compounds by measuring the total fluorescence at a wavelength characteristic for these substances: Ex: 335nm/Em:385nm; we also measured protein-linked pentosidine at the same time points. Finally, we determined the AGE-related total fluorescence in the deproteinized serum of 13 uremic patients on peritoneal dialysis (CAPD) and of 10 healthy controls.Pre-HD AGE-related total fluorescence obtained after 6 months of DHD was significantly lower than that obtained with standard HD (DHD = 201.3 +/- 36.4 AU/ml vs. SHD = 267.5 +/- 141.4 AU/ml, p = 0.03). The extraction rate per minute of dialysis was slightly, but not significantly higher during DHD than SHD (0.29 +/- 0.11% vs. 0.23 +/- 0.04, p = 0.07). AGE-related total fluorescence pre-HD values in patients treated by SHD and DHD were about 20-fold higher than in control subjects. They did not differ from CAPD patients. The pre-dialysis level of protein-linked pentosidine was significantly lower in DHD than in SHD (DHD = 16.12 +/- 4.71 pmol/mg protein, SHD = 22.64 +/- 6.86 pmol/mg protein, p0.01).DHD showed a reduction in AGE-related total fluorescence, although the mean value remained higher than in control subjects. DHD is also accompanied by a decrease in protein-linked pentosidine.

A major cause of morbidity for hemodialysis patients is vascular access failure and/or occlusion. It is commonly believed that an increased frequency of dialysis sessions, among other factors, might lead to a higher rate of fistula complications.To evaluate if patients on daily hemodialysis carry a higher risk of vascular access occlusion, we examined the incidence rate of access occlusion and the survival function of native vascular accesses in patients undergoing daily dialysis (DD; n = 24) as compared to patients on standard three times a week hemodialysis (TWD; n = 124).The mean follow-up time was 3.6 years. In the TWD group 42 patients had a first-access closure, whereas only 2 patients out 24 had a similar event in the DD group. The proportion of first-access closure was 33.9% for TWD and 8.3% for DD (p0.01). The incidence rate was 9.8 (95% CI: 7.2 -13.2) and 2.2 (95% CI: 0.4 - 7.1) events per 100 patient-years for TWD and DD, respectively. The rate difference was 7.6 (95% CI 3.4 - 11.9) events per 100 patient-years, and the unadjusted risk ratio was 4.5 (95% CI: 1.2 - 16.9; p0.01). The mean vascular access survival before closure was 3.3 years in TWD and 3.7 years in DD. Survival curves, obtained considering the first-access closure as the endpoint, showed a significant difference between DD and TWD (log-rank 5.16; p0.05). In a Cox-proportional hazard model the relative risk (RR) of vascular-access closure in TWD remained significant (RR = 4.3; 95% CI 1.1 - 18.2) after adjustment for age.The results of this observational study, conducted on a limited number of DD patients, suggest that daily dialysis might not have an adverse prognostic significance for access closure.

A new connection system for continuous ambulatory peritoneal dialysis (CAPD) has been established, and its efficacy in preventing microbial contamination of the peritoneal cavity has been tested in vitro. The system consists of a Y-shaped channel formed in the bottom of a Plexiglas cup. The Luer-lock shaped ends of the Y-shaped channel are designed to host the connectors from the drainage bag, the catheter transfer set, and the bag of fresh dialysate. Because the connectors from the catheter transfer set and the fresh bag are located at the inner surface of the cup bed, and because the cup is filled with disinfectant during the entire exchange procedure, all at-risk steps are continuously protected by disinfectant (that is, removal of the caps from the connectors, connection and disconnection, replacement of the caps). Still, because the patient could inadvertently extract and contaminate one of the two connectors (although such a possibility is unlikely), the disinfecting efficacy of the system was tested in vitro. Despite contamination with various micro-organisms at the highest possible concentrations, all tests showed negative bacterial growth, thus confirming the absolute efficacy of the system in preventing exogenous transluminal peritonitis.

Renal functional reserve (RFR), resulting from an increase in glomerular filtration (GFR) after protein load, is a matter of debate. In kidney transplant recipients most studies have failed to show conclusive results, reporting either the absence, the reduction or the presence of renal reserve in normo-functioning kidneys. The aim of this study was to investigate RFR in kidney transplant patients as well as the possible hormonal vasoactive alterations underlying the reduction of renal reserve reported in some patients.We studied 8 controls and 25 patients, the latter with no history of acute rejection for at least 12 months and GFR50 ml/min. The 25 patients were divided into 2 groups based on the presence (10) or the absence (15) of RFR.Both the RFR group and the controls experienced a similar increase of GFR after oral protein load: 24.3 +/- 15.57% vs 24.4 +/- 10.8%. The group without RFR showed a paradoxical reduction of GFR after oral protein load: 13.3 +/- 13.2% (p0.001). We analyzed the filtration fraction (FF) and observed that the group without RFR had higher values than the group with RFR and the controls: 0.35 +/- 0.11 vs 0.29 +/- 0.07 (p = 0.01) and vs 0.26 +/- 0.02 (p = 0.04). The hyperfiltration state observed in the group without RFR was sustained by a high level of thromboxane. The urine ratio TxB2/6ketoPgF1alpha was higher in the group without RFR than in the RFR group 0.78 +/- 0.2 vs 0.64 +/- 0.1 (p = 0.01). This ratio decreased only in the RFR group after a meat meal. In all the patients, changes of TxB2/6ketoPGF1alpha were inversely correlated to changes of GFR after a meat meal (r = -0.6, p = 0.01).In conclusion, these data demonstrate that kidney transplant recipients with good organ function can be grouped according to the presence of RFR. RFR appears to be inversely correlated with the TxB2/6ketoPGF1alpha ratio, and its decrease seems to be linked to the failure of thromboxane to decrease and prostacycline to increase after a meat meal.

Objective To investigate the effect on the patient's acidbase status of a 39 mmol/L bicarbonate-buffered continuous ambulatory peritoneal dialysis (CAPD) solution. Design This was an open, controlled, cross-over, two-center study in 9 patients. After three months of treatment with a 34 mmol/L bicarbonate-buffered solution (to) patients were switched to a 39 mmol/L bicarbonate-containing solution for four weeks. At the end of the study period (t4) patients were again treated with a 34 mmol/L bicarbonate-buffered CAPD solution for one month (t8). Results Mean venous plasma bicarbonate level significantly increased during the study and decreased at the baseline level during the control period (to = 22.94±2.54, t1 = 26.74±3.07, t2=28.47±2.68, t3=28.11±3.56, t4=28.71±3.27, t8=24.94±2.56). Arterial blood pH and plasma bicarbonate significantly increased during the study and significantly decreased attheend of the control period (pH: to= 7.37±0.04, t4= 7.42±0.04, t8= 7.37±0.06. Bicarbonate: t0= 21.97±2.57, t4= 25.85±2.02, t8= 21.87±2.89). The changes in plasma bicarbonate during the study period were inversely correlated with the metabolic acid production calculated from the protein catabolic rate and with the apparent distribution space for bicarbonate (ABS) of patients. Conclusions The 39 mmol/L bicarbonate-buffered CAPD solution improved the patient's acid-base status. Potential undesirable metabolic alkalosis could be prevented by analyzing the ABS and the metabolic acid production of patients.

Decrease of HCV viral load and HGF plasma levels increase have been related to HD sessions. Beneficial effects of HGF stimulation in HD on the outcome of HCV liver disease have been described. Aim was to analyze potential differences between intermittent (3 × week) and short daily (6 × week) HD, examining differences between HCV+ and – pts. We studied 41 pts from 2 HD centres, 26 on intermittent HD (6 on line HF), 8 HCV+, and 15 on short-daily HD with 4 HCV+ 40 pts used synthetic HD membranes (low-flux and high-flux). Among HCV + we determined viral load by Amplicor (Roche) pre- and post- HD. All pts were studied for HGF levels (ELISA) baseline, 15 min, end, and at start of the following session viral load is significantly higher preHD and decreases over session. High-flux membranes were more efficient in reducing viremia (67% vs 45%), which level was higher pre- and post-HD principally in patients using low-flux membranes. Viremia in DHD is lower than in intermittent (470067.3 ± 663974.5 vs 1015695.5 ± 1202679.0). HCV+ HCV− p HGF baseline 3261.3 ± 1904.5 2186.5 ± 815.7 0.01 HGF 15 min 8000.0 ± 0.0 7774.0 ± 1129.8 ns HGF end 6142.5 ± 2262.3 4443.7 ± 2515.7 0.03 HGF start 3391.0 ± 1680.6 2311.7 ± 633.6 0.007 HGF at baseline, at the end of the session, and starting the following one was significantly higher in HCV + patients. Maximum increase appears always at 15 min. HGF levels were significantly higher in daily HD than intermittent. Of the 14 patients who showed HGF after session higher than 8000, 8 were HCV+(3 in DHD, 5 high flux), 6 were HCV−(5 DHD and 3 high flux), 14 pts finished HD session with HGF>8000, 8HCV+(3 DHD, 5 high flux) and 6HCV−(5 DHD, 4 high-flux). HGF stimulation appears in daily and intermittent HD, with higher level in the latter; HCV+ showed higher HGF vs negative, independently from the HD frequency; HCV viral load diminishes in all HD sessions, more in those with high-flux membranes. Short-daily HD with high-flux synthetic membranes seems the best option for HCV+ patients, and when performed in home precludes nosocomial transmission.

Objective Using the erythrocyte as a model for other kinds of cells not directly exposed to peritoneal dialysis (PD) solutions, we investigated the tolerance of the cell metabolism to lactate and bicarbonate buffers Design We studied, in vivo (in two groups of 5 PD patients each) and in vitro, the Embden-Meyerh of pathway (EMP) because it represents a potential target for the unphysiological effects of lactate or bicarbonate buffers. The EMP is the main glucose-utilizing route in the red blood cell (RBC), producing energy and reducing power. Methods The enzymatic activities of the key steps in the glycolytic pathway and the energy charge (EC), determined by the levels of phosphorylated adenine nucleotides, were investigated spectrophotometrically and by high performance liquid chromatography (HPLC) in two groups of patients undergoing lactate (L-group) and bicarbonate (B-group) PD, respectively. The in vitro effects of both bicarbonate and lactate buffers on some EMP enzyme activities and energy production were determined. Cellular pH (pHi) was also investigated. Results The B-group showed an EC value near the control levels, while in the L-group a significantly lower EC value was observed (t-test: p < 0.05 vs both B-group and controls). The key enzymes in the EMP, and in particular hexokinase, were higher in the L versus B-group (p < 0.03 for the comparison of the Hk mean values). As demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis, the bound form of glyceraldehyde-3-phosphate dehydrogenase (G-3-PD), an inactive form of this EMP enzyme, was significantly higher in the Lgroup with respect to the B-group (p< 0.004). In thein vitro experiments, high lactate concentrations acutely inhibited the key enzymatic steps of glycolysis, producing a significant decrease in glucose consumption and adenosine triphosphate production. These effects were not observed when bicarbonate was used in the incubations. Bothin vivoandin vitrolactate, but not bicarbonate, induce a significant drop in pHi (p < 0.05). Decreased levels of pHi like those observed in the lactate-incubated RBC were demonstrated to be able to inhibit G-3-PD activity (25±2%) here used as an indicator of the actual decrease in pH. Conclusion This study provides evidence for a damaging action of lactate with respect to bicarbonate buffer on the RBC metabolism. This condition was demonstrated observing a cell energy depletion, which coincidesin vitro with an acute EMP impairment; the lactate accumulation together with the consequent lowering of pHi seem to be responsible for this effect, which was not observed when bicarbonate was used instead of lactate.

A study on event-related P300 potential (ERPs) was performed in 20 patients suffering from chronic uraemia and undergoing haemodialysis in order to assessing the functioning of their cognitive processes. The patients were evaluated before and after a standard treatment of haemodialysis. The P300 potential was studied by means of the "oddball" paradigm and the acoustic modality. Moreover the patients' performance was assessed on the basis of the following psychological tests: the Mini Mental Test, the Number Connection Test and the Digit Span of the Wechsler Adult Intelligence Scale. A significant improvement in the P3 latency was demonstrated following the dialysis treatment. Even though a slight improvement in the N2-P3 deflexion amplitude was recorded after dialysis, it was not statistically significant. These data indicate a positive modification in the speed of the cortical function as a consequence of dialysis. These results suggest that the P3 latency obtained from auditory stimuli can help to assess the benefits obtained through extracorporeal dialysis, especially in the follow-up to the illness.

We employed the so-called event-correlated potential (ECP) P300, a neurophysiological test which explores the circuits of attention and memory in the brain and is altered in subjects with a dismetabolic or degenerative encephalopathy, in order to evaluate the cognitive faculty in two groups of uremic patients [18 on continuous ambulatory peritoneal dialysis (CAPD), 15 on hemodialysis (HD)] comparable with respect to age and time on dialysis. The values of latency (msec) of P300 resulted in CAPD patients 356 +/- 26 in CZ (central zero electrodes) and 357.5 +/- 25 in PZ (parietal zero electrodes), not significantly different from the values in normal controls (341 +/- 14.5 in CZ and 340 +/- 15.6 in PZ) and in HD patients postdialysis (354 +/- 24.4 in CZ and 354 +/- 25.6 in PZ). On the contrary, the predialytic values of HD patients (384 +/- 25.6 CZ and 385 +/- 25.5 in PZ) were significantly different from the postdialytic values and from the values of CAPD patients and controls (p0.01). These results support the conclusion that HD is able to restore a normal cognitive faculty only transiently in the postdialytic phase, while CAPD maintains this important function steadily close to the normal range, thus being clearly better than HD.

In the last few years different authors have observed that kidney transplant recipients with good organ function do not have a renal functional reserve (RFR). This condition is accompained by a high glomerular filtration rate (GFR). We studied RFR in patients with very good organ function under different immunosuppressive therapies, who were divided into groups based on the presence or absence of RFR.

In the last few years different authors have observed that kidney transplant recipients with good organ function do not have a renal functional reserve (RFR). This condition is accompained by a high glomerular filtration rate (GFR) [2–6]. We studied RFR in patients with very good organ function under different immunosuppressive therapies, who were divided into groups based on the presence or absence of RFR.

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The aim of our study was to get information on the immune status of patients who undergo haemodialysis in the presence of an HCV infection. This virus infects not only hepatocytes, but also blood mononuclear cells, in particular B cells [1], but we do not know the role of this lymphocyte involvement in the maintenance and progression of hepatitis. The impairment of the cell-mediated immune response in uraemic patients is well known, for example only 50–60% of uraemic patients undergo a seroconversion after HBV vaccine, compared to 95% of the normal population. Paradoxically the immunodeficiency is concomitant with an activation of related cells which is increased rather than ameliorated by the dialysis treatment [2]. In these patients lymphocytopenia is also present with a reduction of the absolute number of T lymphocytes which remain normal in percentage. The study was performed on the following groups of subjects.

Quantitation of the thrombocytopathy of uraemics may be one useful way of evaluating forms of therapy. 24 patients treated by haemodialysis and peritoneal dialysis at two different times had platelet aggregation studies whose parameters were compared with those of 24 normal persons, 5 successful transplants or 13 untreated uraemics. Renal transplantation and peritoneal dialysis improved platelet function. The haemodialysis procedure itself impaired platelet function: this was not due to heparin.

Peritoneal effluent of patients on chronic ambulatory peritoneal dialysis (CAPD) contains a surface-active material (SAM) made up of phospholipids and showing phosphatidylcholine on thin-layer chromatography. This substance drastically lowers surface tension, helps to repel water and has a lubricating effect. The presence of stratified phosphatidylcholine on the peritoneum might narrow the stagnant dialysate fluid layer and situations which can alter the quantity or composition of SAM may affect peritoneal transport and also, perhaps, the formation of adherences. This led us to verify, experimentally, the presence of phospholipids in basal conditions, after CAPD and during peritonitis and to check if addition of phosphatidylcholine to dialysis liquid is able to modify water transport in patients with low ultrafiltration and peritonitis. Phospholipids in the dialysis effluent of patients who have been on CAPD for a long time are lower than observed in the first days of peritoneal dialysis. A more drastic, significant decrease in phospholipids was observed in patients with low ultrafiltration and in patients with peritonitis. Mean ultrafiltration significantly increases in patients with low ultrafiltration and in those with peritonitis during dialysis exchanges containing phosphatidylcholine (50 mg/l) indicating that the latter is able to restore normal physiological conditions.

Success in culturing human and animal peritoneal mesothelial cells for the purpose of study, led us to determine whether these cells could be autoimplanted in animals and man during peritoneal dialysis in cases of acute and extensive loss of mesothelial surface area. Using an original biopsy technique, we were able to cultivate and characterize from the structural and caryological point of view, human and rabbit peritoneal mesothelial cells. Staphylococcal peritonitis was provoked in 12 rabbits with in-dwelling peritoneal catheters and after 4 days of antibiotic therapy, 6 of them were autoimplanted with cultured mesothelial cells. In the animals sacrificed on the third and sixth days, direct morphological observation and autoradiographic techniques showed that the transplanted cells had taken and revealed a different picture from that in the non-transplanted rabbits.In a 56 year old female diabetic patient, upon insertion of the first peritoneal catheter, a specimen of mesothelial cells was cultured and then frozen. Seven months later after an episode of peritonitis from Candida which dictated removal of the peritoneal catheter, since there was a sufficient number of cultured mesothelial cells and the patient consented, the implant was performed. Peritoneal biopsy by laparoscopy three and six days later showed that the cells had taken. The purpose of the study was merely to show that autoimplant of mesothelium in man and animals is possible.

The short- and long-term effect of hemodialysis with two different membranes — cuprophan and polyacrilonytrile — on platelet aggregation has been investigated in 12 uremic patients undergoing extracorporeal dialysis, passing from one treatment to the other. Cuprophan membranes failed to correct the defective platelet aggregation of uremia, and their thrombogenicity was documented by a fall in platelet count and further impairment of platelet aggregation during dialysis. On the contrary, polyacrilonitryle membranes showed the capacity to correct completely but transiently the platelet aggregation, without changes in platelet count. The results indicate that polyacrilonytrile membranes show a better biocompatibility toward platelets than cuprophan membranes.

Pharmacological investigations with tobramycin have been conducted in animals and in man. In the experimental animal, tobramycin showed lower acute toxicity and lower nephrotoxicity than gentamicin. Moreover, the antibiotic did not cause any significant systemic effects and was rapidly absorbed in the blood and excreted in the urine. The pharmacokinetic evaluation of tobramycin was undertaken in patients with varying degrees of reduced renal function. The influence of peritoneal and extracorporeal dialysis on the removal of the antibiotic from the serum of patients with terminal renal failure was examined. Possible tobramycin treatment schedules for patients with varying degrees of reduced renal function are briefly discussed.

Motor nerve conduction velocity (MNCV), sensory nerve conduction velocity (SNVC) and distal motor latencies times (DMLT) were evaluated both in upper and lower limbs in three groups of 15 patients of comparable age, treated respectively by extracorporeal dialysis (HD), continuous ambulatory peritoneal dialysis (CAPD) and combined peritoneal dialysis (CPD) for comparable sufficiently long periods. Moreover, MNCV was monitored longitudinally in two groups of patients shifted from CAPD to HD and vice versa. The results show a significant superiority of peritoneal dialysis and particularly of CAPD with respect to HD in controlling uremic neuropathy.

Success in culturing human and animal peritoneal mesothelial cells for the purpose of study, led us to determine whether these cells could be autoimplanted in animals and man during peritoneal dialysis in cases of acute and extensive loss of mesothelial surface area. Using an original biopsy technique, we were able to cultivate and characterize from the structural and caryological point of view, human and rabbit peritoneal mesothelial cells. Staphylococcal peritonitis was provoked in 12 rabbits with in-dwelling peritoneal catheters and after 4 days of antibiotic therapy, 6 of them were autoimplanted with cultured mesothelial cells. In the animals sacrificed on the third and sixth days, direct morphological observation and autoradiographic techniques showed that the transplanted cells had taken and revealed a different picture from that in the non-transplanted rabbits. In a 56 year old female diabetic patient, upon insertion of the first peritoneal catheter, a specimen of mesothelial cells was cultured and then frozen. Seven months later after an episode of peritonitis from candida which dictated removal of the peritoneal catheter, since there was a sufficient number of cultured mesothelial cells and the patient consented, the implant was performed. Peritoneal biopsy by laparoscopy three and six days later showed that the cells had taken. The purpose of the study was merely to show that autoimplant of mesothelium in man and animals is possible.