Macrophage stimulating protein may promote tubular regeneration after acute injury

Macrophage-stimulating protein (MSP) exerts proliferative and antiapoptotic effects, suggesting that it may play a role in tubular regeneration after acute kidney injury. In this study, elevated plasma levels of MSP were found both in critically ill patients with acute renal failure and in recipients of renal allografts during the first week after transplantation. In addition, MSP and its receptor, RON, were markedly upregulated in the regenerative phase after glycerol-induced tubular injury in mice. In vitro, MSP stimulated tubular epithelial cell proliferation and conferred resistance to cisplatin-induced apoptosis by inhibiting caspase activation and modulating Fas, mitochondrial proteins, Akt, and extracellular signal-regulated kinase. MSP also enhanced migration, scattering, branching morphogenesis, tubulogenesis, and mesenchymal de-differentiation of surviving tubular cells. In addition, MSP induced an embryonic phenotype characterized by Pax-2 expression. In conclusion, MSP is upregulated during the regeneration of injured tubular cells, and it exerts multiple biologic effects that may aid recovery from acute kidney injury.

Polymyxin-B hemoperfusion inactivates circulating proapoptotic factors

Objective

To test the hypothesis that extracorporeal therapy with polymyxin B (PMX-B) may prevent Gram-negative sepsis-induced acute renal failure (ARF) by reducing the activity of proapoptotic circulating factors.

Setting

Medical-Surgical Intensive Care Units.

Patients and interventions

Sixteen patients with Gram-negative sepsis were randomized to receive standard care (Surviving Sepsis Campaign guidelines) or standard care plus extracorporeal therapy with PMX-B.

Measurements and results

Cell viability, apoptosis, polarity, morphogenesis, and epithelial integrity were evaluated in cultured tubular cells and glomerular podocytes incubated with plasma from patients of both groups. Renal function was evaluated as SOFA and RIFLE scores, proteinuria, and tubular enzymes. A significant decrease of plasma-induced proapoptotic activity was observed after PMX-B treatment on cultured renal cells. SOFA and RIFLE scores, proteinuria, and urine tubular enzymes were all significantly reduced after PMX-B treatment. Loss of plasma-induced polarity and permeability of cell cultures was abrogated with the plasma of patients treated with PMX-B. These results were associated to a preserved expression of molecules crucial for tubular and glomerular functional integrity.

Conclusions

Extracorporeal therapy with PMX-B reduces the proapoptotic activity of the plasma of septic patients on cultured renal cells. These data confirm the role of apoptosis in the development of sepsis-related ARF.

Electronic supplementary material

The online version of this article (doi:10.1007/s00134-008-1124-6) contains supplementary material, which is available to authorized users.

[The concept of ultrapure solution online production]

Online preparation of dialysis fluid, i.e., continuous mixing and immediate use, was introduced in 1964 and has contributed significantly to the expansion of dialysis therapy through simplified handling, improved microbiology, and enhanced efficiency. Online prepared replacement solution for hemofiltration was shown to be clinically safe as early as 1978, but the implementation was delayed for 20 years because of regulatory conservatism. Online preparation of sterile and pyrogen-free solutions for infusion is based on the use of water and concentrates that are mixed and distributed in a hygienically designed and maintained flow path. Ultrafilters with known retention capacity are placed in strategic positions to remove bacteria and endotoxins, which gives a sterility assurance level of at least six magnitudes, as required by the pharmacopoeia for sterile products. Microbiologic testing of the fluid should be applied when designing, validating, and troubleshooting online systems but not for routine quality control, because it only gives retrospective information. Quality assurance has to be built into a system and the way it is operated. The use of ultrapure dialysate must be considered as a suitable option for all hemodialysis modalities. To achieve this goal, one must keep in mind that ultrapure dialysate and infusate result from a complex chain of production where ultra-purity and/or sterility of the final solution relies on the weakest or worst component of the chain. Online fluid preparation, when properly performed, is safe, simple, and cost-effective and enhances the efficiency as well as the biocompatibility of dialysis therapy.

Severe course of primary hyperoxaluria and renal failure after domino hepatic transplantation

We report herein a domino orthotopic liver transplantation (LT), from a 38-year-old woman undergoing liver-kidney transplantation (LKT) for primary hyperoxaluria type I (PH1) to a recipient with cirrhosis and hepatocellular carcinoma. Delayed onset of PH1 and renal failure and 10% residual alanine-glyoxylate aminotransferase (AGT) activity in domino liver justified its use for domino procedure. The clinical course after LKT was similar to that described in other series, including ours. Renal function started promptly and maintained despite sustained hyperoxaluria from dissolution of oxalotic deposits. Conversely, the domino recipient manifested severe hyperoxaluria and developed nephrolithiasis and renal insufficiency with rapid progression over 2 months. A new LT resulted in slow decrease of oxaluria and improvement of renal function. Therefore, PH1 behaved quite differently in these two patients, leading us to conclude that domino LT using livers from PH1 patients should be considered very carefully, only as a bridge to definitive LT in recipients with critical clinical conditions.

Continuum of therapy in progressive renal diseases (from predialysis to transplantation): analysis of a new organizational model

In the aging of Western populations, decreased mortality is counterbalanced by an increase in morbidity, particularly involving chronic diseases such as most renal diseases. The price of the successful care of chronic conditions, such as cardiovascular diseases or diabetes, is a continuous increase in new dialysis patients. However, the increased survival of patients on chronic renal replacement therapies poses new challenges to nephrologists and calls for new models of care. Since its split from internal medicine, nephrology has seen a progressive trend toward super specialization and the differentiation into at least 3 major branches (nephrology, dialysis, and transplantation), following a path common to several other fields of internal medicine. The success in the care of chronic patients is owed not only to a careful technical prescription, but also to the ability to teach self-care and attain compliance; this requires good medical practice and a sound patient-physician relationship. In this context, the usual models of care may fail to provide adequate coordination and, despite valuable single elements, could end up as an orchestra without a conductor. We propose an integrated model of care oriented to the type of patient (tested in our area especially for diabetic patients): the patient is followed-up by the same team from the first signs of renal disease to eventual dialysis or transplantation. This model offers an interesting alternative both for patients, who usually seek continuity of care, and for nephrologists who prefer a holistic and integrated patient-physician approach.

The self-locating catheter: clinical experience and follow-up

BACKGROUND

The self-locating catheter invented by Nicola Di Paolo has been used increasingly in Italy and elsewhere since 1994, with about a thousand patients currently implanted every year. Twelve grams of tungsten inserted into the tip of the conventional Tenckhoff catheter during extrusion does not significantly change its form, but suffices to keep the tip firmly in the Douglas cavity.

OBJECTIVE

The aim of the present study was to confirm our preliminary results in a large population of peritoneal dialysis patients.

SETTING

16 Italian nephrology departments.

RESULTS

In addition to confirming the validity of the new catheter, the present results show that patients with the new catheter have fewer episodes of peritonitis, tunnel infection, cuff extrusion, catheter malfunction, obstruction, and leakage.

CONCLUSION

The present multicenter control study confirms preliminary results and demonstrates that complications of peritoneal dialysis, such as cuff extrusion, infection, peritonitis, early leakage, and obstruction, are statistically less frequent in patients with self-locating catheters than in patients with classic Tenckhoff catheters.

Vascular access survival and morbidity on daily dialysis: a comparative analysis of home and limited care haemodialysis

BACKGROUND

Concerns about vascular access failure may have limited the widespread use of daily haemodialysis (DHD). We assessed the incidence and type of vascular access complications during DHD and other schedules, both at home and on limited care haemodialysis.

METHODS

All patients were treated in a limited care and home haemodialysis unit with a stable caregiver team (November 1998-November 2002). Vascular access failure, surgical treatment, angioplasty and declotting were studied alone or in combination by univariate and multivariate models. We analysed the effects of age, sex, comorbidity, previous vascular events, schedule, setting of treatment (home, limited care), dialysis follow-up, vascular access (native vs prosthetic, first vs subsequent) and setting of vascular access creation. 'Intention to treat' and 'per protocol' analyses were performed.

RESULTS

In 2160 patient-months (home dialysis: DHD 400 months, non-DHD 655 months; limited care: DHD 208 months; non-DHD 897 months), 57 adverse events occurred (27 failures), in which 30 were at home (nine DHD) and 27 were in limited care (five DHD). The probability of remaining free from adverse events at 6 and 12 months was 89% and 80% on DHD and 79% and 76% on other schedules ('intention to treat'). Univariate analyses revealed a significant difference for the setting of the vascular access creation (lower risk of vascular access complications in our centre) and sex (male sex was protective). Logistic regression and Cox analyses confirmed the role for the setting of the vascular access creation.

CONCLUSIONS

Although DHD did not appear as a risk factor for vascular access morbidity or failure at home or in a limited care centre setting, the setting of vascular access creation may influence its success.

EPO or Not-EPO? An Evidence Based Informed Consent

Background

Informed consent is crucial in therapeutic choices; however, the forms presented to patients are often locally developed and information may not be homogeneous.

Objective

To prepare an evidence-based model for informed consent, applied in the case of erythropoietin therapy (EPO) as a teaching tool for medical students.

Methods

Methodological tools of Evidence-Based Medicine (EBM) were developed within the EBM Course in the Medical School of Torino, Italy, as problem solving and patient information tools (5th year students work in small groups under the supervision of statisticians, epidemiologists and experts of internal medicine - nephrology in this case).

Results

Methodological and ethical problems were identified: in the pre-dialysis field, evidence from randomized clinical trials (RCT) is scant; how to use evidence gathered in dialysis? How to deal with implementation? How with the mass media? Do we need to discuss the drug choice with the patients? How to deal with rare and severe side effects?). The “evidence” was searched for on Medline/Embase, by using key-words and free terms. About 680 papers were retrieved and screened. Forms available on the Internet were retrieved and a general scheme was drawn: it included 5 areas: title, aim and targets (patients and family physicians); search strategies and updating; pros and cons of therapy; alternative options; open questions.

Conclusions

EBM may offer valuable tools for systematically approaching patient information; the inclusion of this kind of exercise in the Medical School EBM courses may help enhance the awareness of future physicians of the correct communication with patients.

Flexibility as an implementation strategy for a daily dialysis program

BACKGROUND

Daily hemodialysis (DHD) is an interesting dialysis option, experienced worldwide by only a few hundred patients, because of clinical and logistic limitations. This study describes the main clinical and implementation results of a flexible policy applied in starting a DHD program.

METHODS

The setting is the University Nephrology Center of Turin, Italy (approximately 150 hemodialysis and 50 peritoneal dialysis (PD) patients) where in November 1998 a short daily DHD program was started. Outcome measures were logistical (enrollment rate, indications and drop-outs) and clinical (dialysis efficiency, metabolic control, hypertension and anemia control).

RESULTS

25 patients experienced DHD, 16 (11% of the hemodialysis pool) were on DHD in November 2001; overall the DHD follow-up was 409.1 months (median 18, range 0.7-36 months). Flexibility was applied to schedules (patients modulated dialysis time and could switch to 3-4 sessions/wk); treatment setting (home: 11 patients, limited care center: 13; alternate settings: one); clinical selection (23/25 patients with comorbidity). Main reasons for choice were poor tolerance of previous schedule and the search for "best" treatment. Five patients dropped out (work reasons), one died on DHD and three were grafted. As compared to baseline, dialysis efficiency increased (EKRc pre-DHD 14.5 +/- 2.1 mL/min; 17.4 +/- 2.8 mL/min and 17.7 +/- 3.5 mL/min at 1-6 months; p<0.000). Despite the potentially confusing effect of comorbidity, the main clinical data improved.

CONCLUSIONS

A flexible approach allowed development of DHD in approximately 11% of hemodialysis patients, with promising clinical results, despite frequent comorbidity.

Twenty years of renal replacement therapy in a type 1 diabetic patient: advantages of a multiple choice dialysis system

The prognosis of diabetic patients on renal replacement therapy (RRT) is usually poor. We report on the type 1 diabetic woman with the longest RRT follow-up in our area: over 20 years, half on dialysis, half with a renal graft. CS started RRT at age 27 on peritoneal dialysis (3 years), continued until an underdialysis syndrome developed, was switched to acetate dialysis and, because of poor tolerance, to hemofiltration which with good clinical results, allowing her to become the first Italian patient on home hemofiltration, which continued for 5 years. A cadaver graft lasted for the subsequent decade, despite several complications; afterwards she resumed bicarbonate dialysis, choosing a frequent home hemodialysis schedule. Despite several vascular access problems, her clinical conditions were good enough to candidate her for a second renal transplant, performed 3 years ago. This history of active self-care may draw attention to the advantages of a multiple choice dialysis network.

Home hemodialysis. Revival of a superior dialysis treatment

BACKGROUND

Home hemodialysis is usually considered a superior therapy, whose decline is related to demographic, social, psychological and financial factors as well as to competition with renal transplantation and PD.

METHODS

A home hemodialysis program was started in November 1998 in the University of Torino, Italy (200-210 patients on dialysis). Its main features are the tailoring of dialysis schedules and the acceptance of patients with comorbidity. Nurses assist home sessions in case of short-term problems, while the training center ensures follow-up for long-term clinical and logistic problems.

RESULTS

The program started in November 1998 on a previous one (active from 1970 to 1998; 6 patients on treatment in November 1998). Since then, 25 more patients joined the program. Out of 31 patients followed since November 1998, 4 were grafted, 2 died, and 2 dropped out from training. In June 2001, 15 patients were on home hemodialysis, 8 on training. Dialysis schedules and controls are flexible and tailored; in June 2001, range of dialysis time was 1.20-5 h; sessions: 2-6; 8 patients were on thrice-weekly dialysis, 7 on daily dialysis; all patients reached target EKRc >10 ml/min (median 15, range 11-24 ml/min).

CONCLUSION

Tailored, flexible schedules allowed home hemodialysis in over 10% of our patients, confirming that there is still room for this treatment in our setting.

[Costs of dialysis in hospitalised patients with acute or chronic renal failure, according to area of treatment]

BACKGROUND

In Italy, dialysis reimbursement is regulated by the "Tariffario delle prestazioni ambulatoriali" (G.U. N 216, 14/9/1996), which does not take into account separately the dialysis sessions performed in hospitalised patients. In these cases the dialysis activity is considered within the final DRG (Diagnosis Related Group). Aim of the study was an analysis of production costs of dialysis performed in hospitalised patients, according to the setting in which dialysis is performed (Intensive Care Units (ICUs), other Units, hospital dialysis ward).

METHODS

The direct production costs were assessed by the "bottom-up" technique logic (cost definition from the single elements needed for producing the treatment) referring to specific Cost Centres. The main items considered were health-care staff, dialysis supplies and hardware, blood tests, dialysis data recording and transmission.

RESULTS

During the year 2000, there were 4,450 treatments performed in 490 patients. They included 924 haemodialyses in ICUs; 2,531 in the nephrology hospital dialysis ward; 602 peritoneal dialysis treatments in ICUs-other wards, 393 in the nephrology ward. Direct cost per haemodialysis treatment ranged from 276.05 E (UF) to 413.46 E (HF) in ICU, from 170.47 E (Bicarbonate Haemodialysis) to 275.36 E (Slow Haemofiltration) in hospital dialysis ward; for peritoneal dialysis between 128.95 E (CAPD in dialysis ward) and 282.10 E (CAPD in ICU/other Units). During the year 2000, the global cost of production was 1,038,346.65 E.

CONCLUSIONS

The cost of dialysis in hospitalised patients is high. A dedicated budget is needed to avoid deficits, particularly in highly specialised Units of large referral hospitals.

[Daily dialysis: evaluation of the first year of experience at home and in a limited care center]

BACKGROUND

Among self dialysis treatments, daily dialysis is encountering a growing interest. Aim of this study was to evaluate results of the first year of daily dialysis in our Center.

METHODS

Since November 1998, twelve patients started daily dialysis. One patient started RRT on daily dialysis; one patient was in training; 8 were on home dialysis, 3 in the limited care center. Selection of patients was performed according to wide acceptance criteria as for age (range 33-61 years), dialysis follow-up (range 1-23 years), comorbidity (=/>1 comorbid factor present in 8). Dialysis schedule consisted of 6 sessions per week (2-3 hours), blood flow 250-320 ml/min, individualized dialysate. Occasional shift to 3-4 times per week were allowed for logistic or working reasons.

RESULTS

Results were analyzed taking into account patient satisfaction and main clinical parameters. In 9/12 the choice of treatment resulted from both clinical reasons and patient preferences, while in 3 was due to clinical indications (1/3 dropped out). The main reasons of choice were logistic or research of the best treatment. The most common fears regarded fistula and needle puncturing. Despite the time unconvenience, the rapidly regained well being was the reason for choosing this treatment. Also in this relatively short follow-up the favorable results reported as for weight gain, blood pressure control and metabolic pattern are confirmed. The few side effects were multifactorial (fistula thrombosis after blood pressure normalization, 2 recurrences of atrial fibrillation).

CONCLUSIONS

In conclusion, daily dialysis resulted also in our centre as a promising alternative even in difficult patients.

Patient knowledge and interest on dialysis efficiency: a survey

BACKGROUND

Therapeutic compliance is fundamental on dialysis; however following a therapy requires a prior understanding of it. Aim of the study was to assess the need and interest for information on dialysis efficiency and to prepare a dedicated teaching tool.

METHODS

72 patients, on hemodialysis in two limited-care satellite units, were given a questionnaire testing knowledge and interest on dialysis efficiency. In a subsequent second phase, following patients' suggestions, a cartoon book was prepared and opinions recorded.

RESULTS

63 patients' returned the questionnaire. 79.4% had basic knowledge on routine blood tests, 30.1% were aware of their specific meaning. All patients asked for further information, preferring books to other media. The book "Kt/V as cartoon" was distributed; 71.2% read it, 93% scored it as good-very good. In the Unit employing flexible dialysis schedules, 22/42 patients increased dialysis time.

CONCLUSIONS

Despite insufficient knowledge on dialysis efficiency, patient interest is high. An educational program is feasible and may also give practical results, such as self-increase in dialysis time.

Limits of aortic stop flow infusion chemotherapy in the treatment of advanced cancer

BACKGROUND

Advanced and relapsed tumors remain a challenging disease with a poor and dismal prognosis. Our choice for inoperable tumors consists in a percutaneous treatment strategy involving intra-arterial chemotherapy and hemofiltration, with previous blood stop-flow, which allows high doses of Cisplatin-cisplatinum, cis-diammine-dichloroplatinum (CDDP) and Mitomycin C (MMC) in the tumor-bearing area with minimal systemic toxicity.

METHODS

We analyse the morbidity and mortality associated with stop-flow in 20 patients with unresectable and/or metastatic thoraco- abdominal tumors, non responders to prior systemic chemotherapy.

RESULTS

In our experience, the rate of major side effects of the procedure was 31% with a mortality of 5%. The side effects were related to the radiological procedure and to the chemotherapic treatment. A 74-year-old patient died for acute kidney toxicity within 15 days after the procedure. The other transient toxicity symptoms recorded were: nausea, vomiting, increasing of creatinine levels, diplopia and appearance of necrotic ulcer associated to chemotherapic drugs. Concerning the complications related to the radiological technique, the main problem was the rupture of the balloon stop-flow catheter in four patients.

CONCLUSIONS

Stop-flow is a new procedure that could develop in the future, thanks to the possibility of obtaining a higher dose intensity of chemotherapic drugs in districts or organs affected by advanced tumors, with less systemic side effects. Unfortunately, the uncertain results in terms of increasing survival and the default of effective devices are to be resolved for a wider application of the procedure.

Daily dialysis Kt/V and flexible schedules: is it possible to control efficiency, when and how?

BACKGROUND

Daily hemodialysis is a promising treatment schedule but uniform criteria for defining efficiency are lacking.

METHODS

On our daily dialysis (DD) schedule, duration is flexible (2-3 hours, patients are free to add up to 30 min/session), Qb 250-350 mL/min; dialyser 1.6-1.8 m2. Study was performed on 12 pts on DD for > or = 2 months, with > or = 4 Kt/V on subsequent days, tested in the same laboratory.

GOAL

To evaluate variability and identify a simple method for weekly calculation, Kt/V was assessed for 133 sessions.

RESULTS

On flexible DD, variability of Kt/V-session is high (relative error 4.9%-22%). On flexible schedules, within the time range chosen (2-3 hours) variability of average hourly Kt/V is lower (standard deviation: min (0.014; max (0.052 hour, relative error 4.9%-10%) allowing calculation of weekly Kt/V (averaging 3 sessions: relative error < 6%) suitable for clinical practice.

CONCLUSIONS

Flexible schedules, allowing patients to increase treatment time, are an interesting clinical option, but a challenge for Kt/V assessment.

Modelling the "ideal" self care--limited care dialysis center

Limited care dialysis is an interesting option, which has gained attention in several settings because of the aging of the uremic cohort. The aim of this study was to assess its potential in the Piedmont region in northern Italy, evaluating patients' and care-givers' preferences and testing them in a mathematical model of organisation. The study was conducted in the satellite unit of a university hospital (200-210 dialysis patients), following 35 patients (15 at home, 20 in the center, 10 on daily dialysis). Opinions were collected with a questionnaire and features identified were empirically tested through a simulation model. Most patients (34/35) preferred a small unit, with a stable caring team. Further options were flexibility of dialysis schedule, multiple treatment options, integrated center/home care. These needs could be met by a flexible organization including conventional dialysis (3/week) and daily dialysis (6/week). We employed a simulation model (ARENA software) to calculate the nurses required for each shift and the opening hours and best schedule for the unit. Addition of daily dialysis (2-3 hours) to two conventional 4-5 hour sessions to increased the number of patients followed or "spared" beds, ensuring flexibility. According to patients' best choice (7 dialysis stations), and to the recorded calls, the needs are for two nurses per shift, two shifts per day and six nurses for up to 30 patients in limited care. In conclusion, small centers with flexible schedules can tailor dialysis to patients' needs. A managerial approach is valuable for testing cost/benefit ratios in specific contexts.

[Relationship between risk profiles, prognosis, and outcome of patients with acute renal failure treated with dialysis]

BACKGROUND

The paradox of the increased mortality in the patients with acute renal failure (ARF) although submitted to better cares and newer renal replacement therapies (RRT) has recently prompted to the use of quantitative individual severity scores (ISS) calculating for each patient an individual death probability (DP) in correlation with the risk covariates found before the start of RRT; beside the clinical use, the ISS allow an evaluation of the effect of strategies and modalities of treatments as quantitative additive factors eventually added or subtracted to the base-line individual background of risk. The ideal index should be chosen on the basis of its precocity (origin just at the start of therapy), sensitivity (true positive against false positive results), universality (independence from the development set) and discriminative power (the capability to discern patients potentially treatable from those with an unchangeable prognosis). Indexes already validated in their development set should be used and studied into a different set ("evaluation set").

METHODS

The aim of this study has been: to evaluate a literature index (ATN-ISS, Liaño, developed prospectively in a remote set) in the local (A) environment on 340 patients with ARF successively treated with dialysis (mostly hemo-filtration) studied retrospectively along a 4 year period in our regional hospital and compare its performances with a local index (PDTOR) developed by logistic analysis in the same pool; the fitness of both tests to the real outcome has been evaluated by the Limeshow test and by ROC curves; to compare both indexes in a remote environment (B) of a dialytic pool of 345 patients extracted by a group of 25721 patients treated by 25 Italian ICU (Archidia Study group). The responses of the two indexes have been compared even with the index (SAPSII) prospectively generated at the admittance in the ICU by the Archidia Group.

RESULTS

In the local set (A) TOR-ISS fits well with the outcomes (Limeshow test C2 = N.S.) as expected being evaluated in its own "development" set, while ATN-ISS significantly underestimates deaths, perhaps working on a retrospectively built data-base, that could contain fewer risk elements than necessary. (B) In the remote set, ATN-ISS fits very well, while TOR-ISS significantly overestimates expected deaths, for its retrospective origin or for a real lower death incidence compared to that of its development set. SAPSII shows no correlation at all with the outcome because its calculation is often well before (10 days on average) than the actual start of dialytic treatment.

CONCLUSIONS

In conclusion ATN-ISS, an index built prospectively on a large cohort of patients, fits correctly in a remote prospectively built evaluation set. Retrospective built indexes or data-base don't allow a correct ISS evaluation while ICU indexes (SAPSII, APACHE), generated at the admittance in the ICU should not be used for ARF patients submitted to dialysis.

[Research potential of a regional registry]

BACKGROUND

The need for data bank gathering information in dialysis patients is as old as dialysis. Dialysis Registries presently active are characterized by different policies of data gathering (large vs small number of information) and of use (research vs economical or clinical purposes). Aim of the work was a discussion on the use of a Regional Registry (RPDT, Regional Registry of Dialysis and Transplantation of Piedmont, Italy), gathering since 1981 a wide set of information (about 80 items) on all patients treated in a relatively small area (about 4,300,000 inhabitants).

METHODS

Two researches were selected: the first includes patients treated for > or = 20 years by RRT. Cases were identified on the basis of RPDT data and an inquiry regarding all patients was performed, with specific interest on comorbidity. The second includes diabetic patients on regular RRT, a sample of which was further analyzed in high detail.

RESULTS AND CONCLUSIONS

While a Regional Registry, even gathering a wide set of data is unable to answer to the most qualitative questions, such as quality of life, its archives are a powerful tool to identify cases. Furthermore, ad hoc inquiries may represent a way to control quality of data or to test new fields to be studied. In the case of patients with long RRT follow-up, comorbidity questions were tested before being included on RPDT. In the case of a sample of diabetic patients, type of diabetes and cause of ESRD were controlled. This biunivocal relationship between clinical work-up and epidemiological archives may often interest future perspectives.