Infodemiology of renal diseases: a novel opportunity to investigate public global interest.

OBJECTIVE: The aim of this study was to investigate the global community interest about renal diseases through relative search volumes (RSVs) of Google Trends (GT). MATERIALS AND METHODS: The online interest for the search terms hematuria (H), proteinuria (P), chronic kidney disease (CKD) and dialysis (D) was measured by evaluating RSVs from 2010 to 2019. All countries listed in GT were analysed and those presenting RSVs related to all search terms were considered following geographical position. RESULTS: Mean values of RSVs for D, CKD, H and P were 80±9%, 11±2%, 17±2% and 11±1%, respectively. D is the search term most frequently typed in English-speaking countries. On the other hand, in Latin Countries, the interest for P and H was higher than D. Searching for D, CKD and H are highly correlated whilst correlation coefficients between RSVs for D, CKD, and H with P are lower. Since 2010, the interest for renal diseases maintained stable. CONCLUSIONS: GT is a reliable tool in evaluating global interest for renal diseases in different geographical areas and temporal patterns. Although infodemiology represents a method for investigating the dissemination of information at a global level, our results suggest the need for increasing general population's interest for renal diseases especially, and move from simple interest to global awareness in the view of prevention strategies.

Present and future of kidney replacement therapy in Italy: the perspective from Italian Dialysis and Transplantation Registry (IDTR).

Incidence of kidney replacement therapy (KRT) stabilizes or declines both in Europe and in the US; however, it is predictable that global prevalence of KRT will double by 2030. In this paper, we focus on the patterns of incidence, mortality, and prevalence of KRT in Italy, and we compare, when possible, the findings with other countries. The Italian Dialysis and Transplantation Registry (IDTR) currently collects aggregate data from regional registries. In Italy, KRT yearly incidence is around 160 patients per million population (pmp). This incidence showed an increasing trend up until 2011 with an average annual percentage change (AAPC) of 1.8%, after which it stabilized. Older age is an important determinant for KRT incidence, and it is strongly associated with the variability between Italian regions. Incidence is very stable within patients less than 50 years old; however, it greatly differs between regions for patients over 75 years old, ranging from 400 to 900 pmp. Moreover, the incidence for patients over 50 years old declined from 366 pmp in 2011 to 285 in 2017. An age-period-cohort (APC) model showed a very strong cohort effect, which shows the decline in incidence seems mainly due to the better health conditions of people born after 1940. Mortality rate in KRT patients was 109 per 1000 patient-year (py) between 2011 and 2017 with great differences among treatment modalities: 162 per 1000 py in haemodialysis, 117 per 1000 py in peritoneal dialysis, and 16 per 1000 py in kidney transplantation. Premature death is better detected by the standard expected years of life lost (YLL). The distribution of YLL rate per age shows a sharp increase between 40 and 70 years old both in haemodialysis and peritoneal dialysis patients with an AAPC of 5.2% and 4.1% respectively. Transplanted patients experience a very low YLL rate at any age. KRT prevalence was 1118 pmp in 2017 and it should be close to 1175 pmp by 2025 with a projected increase of transplanted patients' prevalence to 500 pmp, and a decrease of dialysis patients from 714 to 680 pmp. The proportion of patients treated with one of the three modalities strictly depends on age, with a sharp increase of haemodialysis after the age of 50. All data suggests the necessity to improve the care of middle and older age patients who experience the higher incidence of disease and mortality.

Gamma glutamyltranspeptidase activity and viral hepatitis in dialysis population.

BACKGROUND: Numerous investigations have reported that viral hepatitis is associated with significant hepatocellular damage, as expressed by raised aminotransferases in serum, in dialysis population. However, scarce information exists on the activity of gamma glutamyltranspeptidase (GGTP) in dialysis patients with infection by hepatotropic viruses. OBJECTIVES: We measured serum GGTP values in a large cohort (n=757) of patients receiving long-term dialysis; healthy controls were also included. The relationship between GGTP values and a series of demographic, clinical, and biochemical parameters was analyzed. METHODS: Serum GGTP levels were tested by spectrophotometry. A subset (n=333) of dialysis patients was tested by molecular technology (branched-chain DNA (bDNA) assay) to evaluate the relationship between serum GGTP and HCV viremia. A subgroup (n=78) of dialysis patients was analyzed by an ultrasound scan of gallbladder and biliary tract to assess the presence of gallstone disease. Multivariate analyses were made using regression models; serum GGTP values were included as a dependent variable. The usefulness of serum GGTP levels in detecting HBsAg and anti-HCV positivity was evaluated using receiver operating characteristics (ROC) curve analysis. RESULTS: Univariate analysis showed that serum GGTP levels were significantly higher in HBsAg positive and/or anti-HCV positive patients than in HBsAg negative/anti-HCV negative patients on dialysis; 85.1+/-184.1 versus 25.86+/-23.9 IU/l (P=0.0001). The frequency of raised GGTP levels was 22.2% (41/184) among dialysis patients with chronic viral hepatitis. Multivariate analysis showed a significant and independent association between serum GGTP values and positive HBsAg (P=0.005) and anti-HCV antibody (P=0.0001) status. Mean GGTP values were significantly higher in study patients than controls, 32.32+/-60.02 versus 23.5+/-16.92 IU/L (P=0.01); however, no significant difference with regard to GGTP between study and healthy cohorts persisted after correction for age, gender, race, and viral markers. No relationship between gallstone disease and serum GGTP was found (NS). An independent and significant association (P=0.0291) between raised GGTP levels and detectable HCV RNA in serum was noted among patients tested by biology molecular techniques. ROC technology demonstrated that GGTP was equally useful for detecting HBV (P=0.0004) and HCV (P=0.0005) among dialysis patients. CONCLUSIONS: We found an independent and significant association between serum GGTP values and HBsAg and/or anti-HCV antibody in dialysis population. Twenty-two percent of dialysis patients with chronic viral hepatitis had elevated GGTP. No difference in GGTP between HBsAg- negative/anti-HCV- negative dialysis patients and healthy individuals was found. Routine testing for serum GGTP levels to assess liver disease induced by hepatotropic viruses or other agents in dialysis population is suggested.

Intra-dialytic blood oxygen saturation (SO2): association with dialysis hypotension (the SOGLIA Study).

BACKGROUND: Intradialytic hypotension (IDH) has a dramatic impact on the main outcomes of dialysis patients. Early warning of hemodynamic worsening during dialysis would enable preventive measures to be taken. Blood oxygen saturation (SO2) is used for hemodynamic monitoring in the critical care setting and may provide useful information about IDH onset. AIM: To evaluate whether short- and medium-term variations in the SO2 signal (ST-SO2var, MT-SO2var,) during dialysis are a predictor of IDH. METHODS: In this 3-month observational cohort study, 51 hypotension-prone chronic hemodialysis (HD) patients, with vascular access by arteriovenous fistula (AVF) or central venous catheter (CVC), were enrolled. Continuous non-invasive blood SO2 was monitored (fc = 0.2 Hz) by an optical sensor on the arterial line of the extracorporeal circulation; blood pressure (every 30 min), symptoms and their time of appearance were noted. Predictive power of IDH was expressed by the area under curve (AUC) sensitivity and specificity based on intradialytic variations in SO2. RESULTS: A total of 1290 HD sessions were analyzed. Overall, off-line ST-SO2var analysis proved able to correctly predict IDH in 67 % of the sessions where IDH occurred. The best predictive performance was found in the presence of highly arterialized AVF (SO2 > 95 %) (75 % sensitivity; AUC 0.825; p < 0.05). On the contrary, in sessions with CVC, IDH prediction proved more efficient by MT-SO2var (AUC 0.575; p = 0.01). CONCLUSIONS: Intradialytic SO2 variability could be a valid parameter to detect in advance the hemodynamic worsening that precedes IDH. Appropriate timely intervention could help prevent IDH onset.

[Ethical issues in living renal transplantation]. / Problemi etici nel trapianto renale da vivente.

The paper by EA Friedman and AL Friedman, recently published in Kidney International, advocating legislation to govern and regulate kidney sales, stimulated a heated discussion on the Mailing List of the Italian Society of Nephrology (ML-SIN). The aim of this article is to review the main elements of the issue raised by the authors and summarize the messages on this topic. It is known that the steady increase in the number of patients with end-stage renal disease treated by dialysis outpaces the available kidney donors: the approach proposed by EA and AL Friedman to expand the pool of kidney donors is to legalize payment of a fair market price to donors. According to the authors, the case for legalizing kidney trade hinges on the right of individuals to control their body parts. The participants in the discussion on the ML-SIN generally took a critical stance against this proposal, even if they expressed their opinions more or less clearly and used different arguments. The most widely held view among the nephrologists of the ML-SIN is that trade of organs for transplant is unethical and that it is impractical to propose the legislative hypothesis suggested by Friedman in Italy because of the characteristics of its social, cultural and healthcare systems, and because it would necessitate review of all related current laws.

[On the mailing list: use of acyclovir in patients on hemodialysis]. / Sulla Mailing List: uso dell'acyclovir nei pazienti dializzati.

In the SIN Mailing List a message published in May 2004 gave rise to an interesting debate as to the use and dosage of acyclovir in dialysis patients for the treatment of varicella-zoster infection, considering the side effects (mainly neurological) reported in patients affected by renal insufficiency. In this issue, we summarised the main pharmacological characteristics of acyclovir and the clinical indications for using this drug. Finally, we analysed the literature data concerning acyclovir side effects in the setting of renal insufficiency. As they indicate that acyclovir-induced neurotoxicity in renal insufficiency patients may be unpredictable even at reduced dosages, this should discourage the use of acyclovir when severe renal insufficiency is present, unless severe herpes infection is present and after evaluating carefully the risk-benefit. In this case, the patient has to be kept under strict medical control to detect the acyclovir-induced side effects early. The use of new antiviral drugs, such as famciclovir or brivudine, to treat herpes virus infections in patients with renal insufficiency is currently not supported by sufficient data for a critical review.

[From the Mailing List SIN: professional risks for the nephrologists: clinical risk and risk management]. / Dalla Mailing-List soci SIN (ML-SIN). Eventi indesiderati nei Centri Dialisi: Rischio clinico e risk management nel sistema sanitario.

An extensive debate on bacteraemias due to aquatic bacteria has recently developed in the Mailing List SIN. This topic was analyzed in two previous issues where the epidemics observed in two Dialysis Centers have been presented and discussed. The two experiences had in common the difficulty in identifying the source of contamination in industrial products commercialized as ''sterile''. In one case, the source of the epidemic could not be identified, in the other one it was discovered only incidentally thanks to a notice of the supplier company of the contaminated material. This underlines the importance of defining specific operating protocols in case of hospital epidemics and stresses the issues related to the professional risk and the potential legal implications.

[Epidemiology and demography of uremia: data from the Lombardy Dialysis and Transplantation Registry (RLDT)]. / Epidemiologia e demografia dell'uremia: dati dal Registro Lombardo Dialisi e Trapianto (RLDT).

The Lombardy Registry of Dialysis and Transplantation (RLDT) since 1983 has collected data concerning patients affected by end-stage renal disease (ESRD) on renal replacement therapy (RRT) in Lombardy, a region of Northern Italy with 9 million inhabitants. This report illustrates the main features of ESRD patients on RRT: there were 6589 patients undergoing treatment at 31 December 2003, with a prevalence rate of 727 pmp. Patient numbers regularly increased by 4.5%/yr for the last 5 yrs. This phenomenon is probably due to the high incidence rate (172 pmp) of ESRD patients in Lombardy during these years related to a relatively stable mortality rate (15.2%). The increasing incidence is probably correlated to the population's characteristics: higher rates (189-223 pmp) were observed in certain provinces (Cremona, Lodi and Pavia) with a larger elderly population (people >65 yrs = >20%, people <65 yrs = <16%). Of dialysis modalities, 85% of prevalent patients were on hemodialysis (HD), 55% in hospital, and 30% in limited care units. The number of patients treated by peritoneal dialysis (PD) was stable during the last years, but showed a slow percentage decline (15% during 2003) since 1999. However, PD remains the first dialysis modality for 21.4% of new patients, with a wide variability among renal units. Regarding HD, highly efficient techniques (on-line hemodiafiltration (HDF)) represented 19.2%, with a significant increase (1.8%) compared to 2002. During 2003, the number of dialysis units in Lombardy was stable; there was only an increase in facility beds in limited care units in order to treat the increasing numbers of uremic patients.

[From the Mailing List SIN: Therapy and prevention of peritoneal sclerosis]. / Dalla Mailing-List soci SIN (ML-SIN). La sclerosi peritoneale: terapia e prevenzione.

Recently, in the Mailing List of the Italian Society of Nephrology (ML-SIN), a message asking for opinions on the diagnosis and treatment of peritoneal sclerosis gave rise to an extensive debate on this interesting clinical topic. The discussion evidenced significant differences both in the reported onset of clinical manifestations, emphasizing the difficulty in obtaining a definite early diagnosis, and in therapy approaches. Occasionally, this is limited to medical treatment, but surgery, although burdened with elevated complexity and high mortality rates due to post-operative complications, is usually advocated for intestinal obstruction. This is the second issue reserved for the review of the ML-SIN concerning this topic, following that dedicated to definition, etiology, pathology and clinical characteristics. In this section, two expert colleagues complete the analysis of the different aspects of peritoneal sclerosis, discussing the therapy and the prevention of this serious complication of peritoneal dialysis.

[From the Mailing List SIN: peritoneal sclerosis]. / Dalla Mailing-List soci SIN (ML-SIN): la sclerosi peritoneale.

In the course of previous months, in the Mailing List of the Italian Society of Nephrology (ML-SIN), a message asking for opinions on the diagnosis and treatment of peritoneal sclerosis, gave rise to an extensive debate concerning this clinically interesting topic. The discussion evidenced significant differences both in the reported onset of clinical manifestations, emphasizing the difficulty in obtaining a definite early diagnosis, and in therapy approaches. This is sometimes limited to medical treatment, but surgery, although burdened with elevated complexity and a high mortality rate, mainly due to post-operative complications, is usually advocated for intestinal obstruction. In this issue of the review dedicated to the ML-SIN, two expert colleagues will analyze the different aspects of peritoneal sclerosis. The argument is developed in two sections: the first section is dedicated to the discussion of definition, etiology, pathology and clinical characteristics of this serious complication in peritoneal dialysis (PD).

[From the Mailing List SIN: Epidemic of infections caused by 'aquatic' bacteria in patients undergoing hemodialysis via central venous catheters]. / Dalla Mailing-List soci SIN (ML-SIN). Epidemia di infezioni causate da batteri 'acquatici' in pazienti emodializzati tramite cateteri venosi centrali.

UNLABELLED: Bacteremia due to central venous catheter (CVC) infection is the most frequent complication of CVC use as vascular access for hemodialysis (HD). We report a case of an epidemic of CVC infections caused by 3 strains of unusual bacteria: Ralstonia pickettii (Rp), Leifsonia xyli/Leifsonia aquatica (Lxa), Tsuckamurella strandjordae (Ts). From 20/8/01 to 30/9/01, 23 of 35 patients dialyzed via CVCs experienced intra-HD pyrogenic reactions. Their hemocultures were positive for: Rp (14 pts), Lxa (3 pts), Rp+Lxa (5 pts) and Rp+Ts (1 pt). The hemocultures of 12/35 asymptomatic pts were positive for: Rp 2 pts, Lxa 2 pts, Rp+Lxa 2 pts, Ts 1 pt, Rp+Ts 1 pt. The epidemiological and microbiological analyses of environmental samples failed to identify the source of the epidemic. Actions taken were: a) replacement of the batches of disposable materials; b) removal of CVCs in cases where possible to prepare a different access; c) treatment of the infections with intra-CVC antibiotic lock therapy. No relapses were recorded until April 2002, when 8 pts had again pyrogenic reactions due to Rp. After quick substitution of the CVC and repetitions of the action a), no relapses of pyrogenic reactions were observed. CONCLUSIONS: 1) given the characteristics of Rp, Lxa and Ts, saprophytes of moist environments, the most plausible source of the epidemic was a low-charge contaminated solution that was not identified due to low sensitivity of environmental sample culturing methods; 2) antibiotic lock therapy is a viable option for the conservative treatment of CVC infections.

Transcoronary platelet thromboxane A2 formation without platelet trapping in patients with coronary stenosis-effect of sulphinpyrazone treatment.

Platelet count, and plasma thromboxane B2 (TXB2) and circulating platelet aggregates (CPA) were determined in the coronary sinus (CS), aortic bulb (AO) and cubital vein (V) in 21 patients with stable angina and in 6 control subjects before and after atrial pacing (AP). TXB2 measurements were repeated before and after AP in 6 of the 21 angina patients after 15 days' sulphinpyrazone treatment. Platelet count and CPA ratio were similar in angina patients and controls at all three sampling sites and were unchanged at AP peak. In the controls, basal TXB2 values in CS, AO and V were not significantly different and were unchanged at AP peak. In the angina patients compared with the controls, basal TXB2 values in the AO, CS and V were not significantly different whereas the CS/AO TBX2 ratio was significantly higher; at AP-induced ischaemia, CS TXB2 was significantly increased and the CS/AO TXB2 ratio was increased. A weak but significant direct correlation was found between CS/AO TXB2 ratio and coronary score. Sulphinpyrazone treatment reduced CS TXB2 levels at rest and after AP, but not the ischaemic threshold at AP.

Survival of diabetic patients on peritoneal dialysis or hemodialysis.

Our objective was to analyze the survival of diabetic patients on renal replacement therapy and to compare their survival on extracorporeal and on peritoneal dialysis. All data regarding diabetic patients admitted to dialysis between 1 January 1983 and 31 December 1993 were collected by means of individual patient questionnaires sent to all of the 44 regional Renal Units (100% answers) of Lombardy, Italy. Cox proportional hazards model, stepwise procedure, was applied in order to select the covariates significantly associated with survival. Age (at baseline), sex, type of diabetes, initial modality of treatment (hemodialysis or peritoneal dialysis), and initial clinical risk factors (malignancies, serious heart disease, vascular disease, cirrhosis of the liver, cachexia) were considered. Descriptive analysis of survival was performed using the Kaplan-Meier technique. The survival of all diabetic patients (895) was 86.5% at one year, 52% at three years, and 34% at five years. The main causes of the 488 deaths of diabetic patients were cardiovascular diseases (56%), cachexia (18%), and infections (11%). The relative death risk of patients on peritoneal dialysis versus those on hemodialysis, after taking into account the main comorbid conditions, did not significantly differ from 1, as estimated by the Cox proportional hazards regression model. Five-year survival of diabetic patients was 34%, and no differences were found between peritoneal dialysis and hemodialysis as far as mortality is concerned.

Comparison of survival in CAPD and hemodialysis: a multicenter study.

We studied 1,622 patients who started regular dialysis treatment between 1985 and 1989 in 19 centers from the Italian CAPD Study Group. There were 962 pts (59%) and on HD; 660 pts (41%) on CAPD. CAPD pts were older and had more risk factors at the start than HD pts (p < 0.0001). Overall patient survival was not statistically different between CAPD and HD at 6 years (42% CAPD; 54% HD). Multivariate analysis (Cox's model) on all population revealed that age and pretreatment risk factors had a statistically significant impact on patient survival (p < 0.0001), but not the type of dialytic treatment (CAPD or HD). When multivariate analysis was applied separately by treatment modalities, in HD group age and risk factors had the same negative influence on survival (p < 0.0001) while in CAPD group the influence of age on survival was less significant (p 0.025). This multicenter study carried out with appropriate statistical methods in a large number of pts demonstrates that patients' survival at 6 years is not different on CAPD and HD (despite the worse patient selection on CAPD) and can be even better on CAPD for aged patients.

[The activity of the Soci SIN Mailing List (ML-SIN): an update]. / aggiornamento sull'attività della Mailing List Soci SIN (ML-SIN).

The Soci SIN Mailing List (ML-SIN) is the automatic on-line moderated discussion group for nephrology professionals of the Italian Society of Nephrology, which regularly operates since October 2000. The new publishing initiative of the Giornale Italiano di Nefrologia reserves to the ML-SIN a special survey in which the most discussed topics will be summarised and commented. This paper presents an update of the last six months (October 2003 - march 2004) of ML-SIN activity. The number of ML-SIN members has increased from 525 to 603 (+15%), thus confirming an increasing interest in the ML-SIN as discussion instrument and reliable source of professional advice for the Italian nephrological community. The number of messages received and accepted was 1024, for the most part (49%) related to general or organizational topics (i.e., regulatory information, meeting announcements and management issues) and only 51% to scientific debate. Some of the topics are discussed in detail, e.g. the proposal for a retrospective study on cholesterol crystal embolism and the analysis of dialysis treatment reimbursement rates by the Health System Financial Organization.

[From the Mailing List of the Italian Society of Nephrology: use of isolation rooms for HBV-positive patients in dialysis--part two]. / Dalla Mailing List SIN: utilizzo di sale contumaciali per pazienti HBV positivi in dialisi (seconda parte).

In the course of recent months, on the mailing list of the Italian Society of Nephrology (ML-SIN), a message asking for opinions on preventative measures for HBsAg patients has stimulated an extensive debate, in particular on the use of separate dialysis rooms. The discussion evidenced significant differences in the procedures adopted, not only between dialysis units, but also in regional health systems' directives. This emphasizes the necessity in dealing carefully with this problem, taking into account the scientific evidence of the infectious risk and epidemiological profile of hepatitis B virus (HBV) in dialysis patients. Moreover, potential solutions must be considered in terms of their effective cost benefit ratio. To complete the previous article, which examined the question from the viewpoint of an expert nephrologist, this issue of the review dedicated to the ML-SIN reports the opinion of an infectious diseases specialist, identified for its scientific contribution to this specific discussion.

[From the Mailing List of the Italian Society of Nephrology: Pharmacological therapy and plasma exchange in the treatment of HCV-associated cryoglobulinemia]. / Sulla Mailing List di maggio: ruolo della terapia farmacologica e della plasmaferesi nel trattamento della crioglobulinemia associata al virus dell'Epatite C.

The Mailing List SociSIN (ML-SIN) is beginning to develop, beside more experienced organisational topics, there is also some discussion on clinical topics. During the month of May, some messages requesting the opinion of experienced Colleagues on the use of plasma exchange in the cryoglobulinaemia correlated with HCV have risen an interesting debate on this argument. This issue of the review dedicated to the ML-SIN presents a short introduction dedicated to the definition, the main characteristics and the therapeutic bases of the cryoglobulinaemia associated to HCV. The messages on this topic are then summarised and, finally, the opinion of an expert on the matter is reported. The expert is chosen on the basis of the importance of his international scientific contribution to this particular topic.

[Italian Registry of Dialysis and Transplantation: 1996-2001 experience]. / Registro Italiano Dialisi e Trapianto. Esperienza 1996-2001.

The Italian Registry of Dialysis and Transplantation (RIDT) was born in 1996 under the aegis of the Italian Society of Nephrology, and it is organized as a federation of regional registries. This study aimed to completely revise the epidemiological data collected during the first 5 yrs (1996-2001) of RIDT activity to evaluate the trends of the main epidemiological features. During this period, regional registries were not always able to assure complete and exhaustive information according to RIDT requirements, owing to different levels of organization and functioning. To avoid any possible error in data analysis, information inadequately assessed was refused. The incidence of end-stage renal disease (ESRD) patients on renal replacement therapy (RRT) in Italy has increased from 114 pmp in 1996 to 139 pmp in 2001, that means an increase of 3.5%/yr, corresponding to 5718 patients during 1996 and 8000 patients during 2001. Primary renal diseases (according to the EDTA) in incident ESRD patients are vascular and diabetic nephropathy. Main dialysis modality in incident patients was hemodialysis (HD) (85%), while peritoneal dialysis (PD) was only 15%; pre-emptive transplantation was a very unusual modality. The prevalence of ESRD patients at 31 December was 693 pmp in 1996 and 827 pmp in 2001; among dialysis patients, the corresponding rates were 575 pmp and 657 pmp, respectively. Consequently, the number of dialyzed patients increased, respectively, from 28892 to 37919. The prevalent dialysis modality was bicarbonate dialysis in 74% of cases, followed by hemodiafiltration (HDF) in 15%, continuous ambulatory peritoneal dialysis (CAPD) in 7% and APD in 3%. The gross mortality rate in dialyzed patients was stable during this period, at approximately 14%, the main causes of death being cardiovascular diseases and cachexia.

Vascular access for chronic haemodialysis in elderly patients: the Lombardy experience.

The growing proportion of elderly patients largely accounts for the striking increase in number of patients admitted to renal replacement treatment (RRT) in recent years. Most of them are treated with haemodialysis, which involves various problems connected with vascular access. A survey was therefore conducted amongst the Dialysis Units of Lombardy. The aim was to evaluate how vascular access surgery for elderly patients is or-ganized, and which techniques are used to monitor surgical access as well as the central catheters (CVCs). A questionnaire was sent to the 43 Lombardy Units, 79.1% of which replied. The results of a previous study analyzing the same topics in all patients on RRT in Lombardy were considered as 'controls'. In this way it was possible to compare the strategy used for elderly patients with that of the general dialysis population. Forty-one percent (41%) of elderly patients in Lombardy were started on RRT using acute CVCs. This percentage is quite similar to that documented (39%) in the general dialysis population. The distribution is quite dif-ferent when we consider the patients alive on RRT at 31 December 1999, when a permanent vascular access (distal AVF, proximal AVF or AV graft) was used in about 70% of cases. For elderly patients, as for the general RRT population, first choice access is mainly (79%) distal arterio-venous fistula (AVF) with end-to-end, side-to-side with distal ligature of the vein or side-to-end anastomosis. As a second choice, proximal AVF is more widely used than AV grafts, which are implanted only when all native vessels and related surgical procedures are exhausted. CVCs are valid solutions not only as temporary access, but also as an alternative permanent solution to the problems related to elderly dialysis patients. In the elderly, the jugular vein is the most frequent site of inser-tion for chronic tunnelled devices (91%) and the femoral vein for acute CVCs (40%). Despite the documented incidence of related episodes of stenosis/obstruction, the subclavian vein is used as a temporary access in quite a high percentage of cases (22% in the elderly and 32% in the general RRT population). Only in selected cases diagnostic procedures (mainly Venography and Doppler studies) are performed prior to permanent access choice. Similarly, vascular access is monitored mainly using a recirculation test, albeit not routinely. As in the general dialysis population, in the cases of vascular access thrombosis and stenosis, surgical re-vision is the most common approach.

Vascular access for chronic haemodialysis in Lombardy.

To evaluate the organisation of vascular access surgery, the techniques used to monitor surgical access and the central catheters, a survey was conducted amongst dialysis Units of Lombardy. A questionnaire was sent out to the 43 dialysis centres in Lombardy, 96% of which replied. In almost 90% of dialysis units nephrologists perform vascular access albeit in close cooperation with vascular surgeons for the more complex cases. First choice access is by distal arteriovenous fistula (AVF): 36% end-to-end, 31.7% side-to-end, and 19.5% side-to-side with distal ligature of the vein. As second choice proximal AVF is more widely used than AV grafts, which are implanted only when all native vessels and related surgical procedures are exhausted. Central venous catheters offer valid solutions not only as temporary access, but also as an alternative permanent one. In both cases the jugular vein is the most frequent site of insertion. Despite the documented incidence of related episodes of stenosis/obstruction, the subclavian vein is used as a temporary access in quite a high per-centage of cases. Only in selected cases are diagnostic procedures (mainly Venography and Doppler studies) performed prior to permanent access choice. Similarly vascular access is monitored mainly using a recirculation test albeit not routinely. In case of vascular access thrombosis, surgical revision is the most common approach.