[Effects of dose of erythropoiesis stimulating agents on cardiovascular outcomes, quality of life and costs of haemodialysis. the clinical evaluation of the DOSe of erythropoietins (C.E. DOSE) Trial]. / Effetti della dose degli agenti stimolanti l'eritropoiesi su esiti cardio-cerebrovascolari, qualità di vita e costi in emodialisi.

BACKGROUND: Anaemia is a risk factor for death, adverse cardiovascular outcomes and poor quality of life in patients with chronic kidney disease (CKD). Erythropoietin Stimulating Agents (ESA) are the most used treatment option. In observational studies, higher haemoglobin (Hb) levels (around 11-13 g/dL) are associated with improved survival and quality of life compared to Hb levels around 9-10 g/dL. Randomized studies found that targeting higher Hb levels with ESA causes an increased risk of death, mainly due to adverse cardiovascular outcomes. It is possible that this is mediated by ESA dose rather than haemoglobin concentration, although this hypothesis has never been formally tested. METHODS: We present the protocol of the Clinical Evaluation of the Dose of Erythropoietins (C.E. DOSE) trial, which will assess the benefits and harms of a high versus a low ESA dose therapeutic strategy for the management of anaemia of end stage kidney disease (ESKD). This is a randomized, prospective open label blinded end-point (PROBE) design trial due to enroll 900 haemodialysis patients. Patients will be randomized 1:1 to 4000 UI/week i. v. versus 18000 UI/week i. v. of epoetin alfa, beta or any other epoetin in equivalent doses. The primary outcome of the trial is a composite of cardiovascular events. In addition, quality of life and costs of these two strategies will be assessed. The study has been approved and funded by the Italian Agency of Drugs (Agenzia Italiana del Farmaco (AIFA)) within the 2006 funding plan for independent research on drugs (registered at www.clinicaltrials.gov (NCT00827021)).

[2004 census of the Italian nephrology and dialysis units]. / Censimento 2004 dei Centri di Nefrologia e Dialisi Italiani.

The Italian Society of Nephrology (SIN) promoted a census of the renal and dialysis units to analyze structural and human resources, organizational aspects, activities and epidemiological data. An online 158-item questionnaire for the year 2004 was used. Three hundred sixty-three public renal units, 303 satellite dialysis centers and 295 private dialysis centers were identified, resulting in a total of 961 dialysis centers (16.4 per million population, pmp). The inpatient renal beds were 2,742 (47 pmp). Renal and dialysis activity was performed by 3,728 physicians (64 pmp), of whom 2,964 (80%) were nephrologists. There was no permanent medical assistance in 41% of the satellite dialysis centers. Renal admissions (1,800 pmp) and renal biopsies (99 pmp) were done. The management of the acute renal failure was one of the most relevant activities in the public renal units (13,456 cases, 230 pmp). In 2004 9,858 new cases of end-stage renal disease (169 pmp) were diagnosed. On December 31st 2004, 43,293 patients (741 pmp) were on renal replacement therapy, of whom 89.7% on hemodialysis and 10.3% on peritoneal dialysis. Renal transplant recipients were 16,765 (287 pmp). The benchmark data derived from this census show interesting comparisons between centers, regions and groups of regions. These data realised the clinical management of renal disease in Italy.

[Thrombotic microangiopathy during urinary tract infection]. / Un caso di microangiopatia trombotica in corso di infezione urinaria.

An 84 year-old woman was admitted because of sepsis, thrombocytopenia, anaemia and acute renal failure that required hemodialysis. The diagnostic tests performed during hospitalization showed a severe urinary tract infection due to Enterococcus faecalis, resulting in mild sepsis. This infection was responsible for acute tubular necrosis and thrombotic microangiopathy, in a clinical context of difficult differential diagnosis and hemolytic-uremic syndrome.

[Census 2004 of the Italian Renal and Dialysis Units--Piemonte, Liguria and Valle d'Aosta]. / Censimento 2004 dei Centri di Nefrologia e Dialisi italiani. Piemonte--Liguria--Valle d'Aosta.

The Italian Society of Nephrology (SIN) promoted a national survey in order to obtain detailed information from all Renal and/or Dialysis Units using the on-line questionnaire (158 items) regarding structural and technological resources, medical workforce organisation and activity features. The purposes of this initiative were to obtain regional benchmarks as references for renal units and to describe the current Italian renal network in order to plan further interventions for the next 5 years. In this paper data of the first three Italian Regions (Piemonte, Liguria and Valle d'Aosta) which completed the survey (100% of the units) are reported. Main findings in the 3 Regions. A) Epidemiology: prevalence of dialysis patients = 709, 720, 787 pmp (per million population); prevalence of transplanted patients = 325, 387, 279 pmp; incidence of dialysis patients = 166, 191, 156 pmp; gross mortality of dialysis patients = 13.7, 15.0, 13.0%; distribution of vascular access in prevalent dialysis patients: arteriovenous fistula = 74, 83, 76%, central venous catheter = 18, 12, 15%, vascular graft = 8, 5, 9%. B) Structural resources: hospital's number of beds = 49, 72, 49 pmp, dialysis places = 166, 158, 164 pmp. C) Personnel resources: renal physicians = 44, 47, 41 pmp, renal nurses = 186, 194, 205 pmp; each renal physician takes care of 16, 15, 19 dialysis patients and each renal nurse cares for 3.8, 3.7, 3.8 dialysis patients. D) Activity: admission to hospital = 1507, 2392, 1606 pmp, renal biopsies = 109, 133, 57 pmp. Despite discrepancies in population density in the three Regions, most indexes are surprisingly similar and show the satisfactory level of renal care attained in the Northwestern Italian area. Further improvements in health care management can be predicted as a consequence of a direct comparison between needs and results in the various Regions of the Country.

[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.

Antiphospholipid antibodies and hypertension.

Hypertension is a common manifestation of antiphospholipid syndrome (APS). Antiphospholipid antibodies (aPL) have been described in patients with hypertension secondary to renal artery stenosis (RAS). Twenty-six patients with RAS and 25 patients with severe essential hypertension (diastolic blood pressure > 110 mmHg or > or = 3 hypertensive drugs) were studied and compared to 61 age- and sex-matched healthy subjects. Serum samples were tested for lupus anticoagulant (LA), anticardiolipin (aCL) IgG and IgM, antiprothrombin (aPT) IgG and IgM, anti-beta2glycoprotein 1 (abeta2GP1) IgG and IgM. aPL were negative in all patients with RAS. Two patients with essential hypertension had positive aPL (8%) (LA in one patient confirmed in a second assay and abeta2GP1-IgG in the other patient confirmed one year later together with aCL IgG positivity). Among healthy subjects, one case (1.6%) was found to be positive for LA, aCL IgM, abeta2GP1 IgM, aPT IgG, aPT IgM. In conclusion, the association between RAS and aPL seems to be casual rather than an expression of an elective thrombotic localization ofAPS. The positive finding of aPL in 8% of patients with essential hypertension, a frequency higher than that of the control population, deserves further studies in larger series to better explore the relationship between aPL and hypertension.

[Clinical and instrumental surveillance of the arteriovenous fistula]. / La sorveglianza clinica e strumentale della fistola arterovenosa.

Stenosis and thrombosis are the most important complications leading to vascular access failure in hemodialysis (HD). Aiming for an early access dysfunction diagnosis and elective repair of the failing access, the DOQI guidelines recommend that all HD patients undergo a program of regular monitoring and surveillance. The K/DOQI 2000 update identifies specific types of evaluation for dialysis accesses. First nephrologists should examine patients by inspecting, ausculting and palpating the access at least every 4-6 weeks when patients are not being dialyzed. In addition, access surveillance should be regularly performed by various techniques, i.e. urea recirculation test, dialysis venous pressure measurement and access blood flow assessment. Recently many methods have been proposed and implemented. Ultrasound dilution is the most commonly used. This technique relies on the change in ultrasound velocity when blood is diluted with a normal saline bolus at a known dialyzer blood flow rate, after the lines have been reversed. Following the use of blood ultrasound dilution, multiple technologies have been implemented for access flow measurement with line reversal, i.e. hematocrit (Hct) dilution, thermodilution, conductivity variation assessment. There are three other methods that do not require line reversal: i.e. transcutaneous access flow (TQA) assessment, glucose pump test (GPT) and the variable flow Doppler. Finally, duplex scanning can provide both the anatomy and blood flow of the access. With a Qa <600 mL/min or <1000 mL/min, but reduced by 25% in 4 months, K/DOQI suggest performing angiography and eventual elective repair.

[Treatment of septic shock with the use of CPFA (associated plasma filtration and adsorption): impact on hemodynamics monitored with PiCCO ]. / Trattamento dello shock settico con l'impiego della CPFA (plasmafiltrazione e adsorbimento associate): impatto sull'emodinamica valutata con sistema PiCCO

BACKGROUND: Septic shock represents an emerging pathology and sepsis and its complications are the main cause of death in medical and surgical intensive care units. Single-target therapeutic trials failed to demonstrate any benefit, suggesting that the unselective removal of different mediators may be a more appropriate approach. METHODS: We evaluated a new technique (CPFA) combining a plasma-adsorption (with plasma filter and sorbent cartridge) with a traditional 'slow' extracorporeal treatment on 10 patients, 7 men and 3 women (mean age 53.8+/-16.3), all on mechanical ventilation, with septic shock and multiorgan failure. To identify easily comparable clinical data, the hemodynamic parameters of the patients were monitored with a recently developed, minimally invasive technology, Pulsion PiCCO . RESULTS: We obtained significant improvement of pre- versus post-treatment mean arterial pressure 77.2+/-12.5 vs. 83.3+/-14.1 mmHg (p<0.0001), cardiac index 4.03+/-0.89 vs. 3.46+/-0.82 L/m2/min (p<0.0001), indexed systemic vascular resistances 1388+/-496 vs. 1753+/-516 dynes x sec/cm5 (p<0.0001), PaO2/FiO2 ratio 204+/-87 vs. 232+/-81 (p<0.0001), and norepinephrine requirements 0.13+/-0.07 vs. 0 y/kg/min after a mean of 5.3+/-2.7 consecutive treatments. The survival at day 28 was 90%. Seven patients were discharged from the intensive care unit after a mean of 37.8+/-24 days (range 10-93). CONCLUSIONS: Our data suggest a promising role for CPFA in improving hemodynamics and correcting vasoparalysis in septic shock. Moreover, the noninvasive monitoring of hemodynamic parameters with PiCCO could become a useful tool for estimating the effect of treatment and gaining easily comparable data in different patients.

How well are hypertension and albuminuria treated in type II diabetic patients?

The purpose of this study was to assess the management of both hypertension and micro/macroalbuminuria in a cohort of type II diabetic patients. In the first 6 months of the year 2000, 5815 diabetic patients were identified through prescriptions for antidiabetic drugs in our sanitary district (191 568 inhabitants). In all, 65% (3810) of these type II diabetic patients were also given prescriptions for antihypertensive drugs. A total of 400 diabetic patients were randomly selected and 171 entered the study (gender: 94/77 M/F; age: 66.6+/-8 years; diabetes duration: 12+/-9 years): 100 patients (group DT) were treated with antihypertensive drugs and 71 (group DU) were untreated. Blood pressure, urine albumin-to-creatinine ratio (ACR), and glycated haemoglobin were measured in the two groups. A total of 80% (57/71) of DU patients were hypertensive (BP>/=130/85 mmHg). Specifically, 24.4% had diastolic hypertension (BP>/=85 mmHg) and 79% systolic hypertension (BP>/=130 mmHg). Only 63% (100/157) of the hypertensive patients were treated with antihypertensive drugs (two drugs/patient on average, range 1-5). In addition, only 13% of the DT patients were adequately controlled (BP<130/85 mmHg), while the others had above target blood pressure levels (14%: 130-139/85-89 mmHg; 40%: 140-159/90-95 mmHg, and 33%>/=160/95 mmHg). Angiotensin converting enzyme inhibitors (ACE-I) and angiotensin receptor blockers (ARB) were included in the antihypertensive medical regimen in 70% of the DT patients (ACE-I: 62%; ARB: 8%; diuretics: 39%; dihydropyridine calcium antagonists: 38%; alpha-blockers: 20%, beta-blockers: 17%; clonidin: 8%; nondihydropyridine calcium antagonists: 5%). Only 33% of type II diabetic patients underwent a screening for microalbuminuria as assessed on clinical records. The same percentage of micro- and macroalbuminuric patients (13.5%) was observed in the DT group, whereas 25% micro vs 3% macro were found in the DU group. In all, 73% of microalbuminuric patients were not on ACE-I/ARB. Hypertensive type II diabetic patients were often left untreated and only a minority of those treated were optimally controlled. The importance of an elevated systolic pressure is underestimated and the number of antihypertensive drugs prescribed insufficient. Screening and treatment of albuminuria are inadequate.

[Contrast nephropathy in cardiac procedures: no advantages with prophylactic use of N-acetylcysteine (NAC)]. / Nefropatia da contrasto in cardiologia interventistica: assenza di vantaggi con impiego profilattico di N-Acetilcisteina.

BACKGROUND: Acute renal failure induced by contrast agents represents the third cause of acute nephropathy in hospitalized patients. Some mediators are potentially involved in this process: recent data underscored the role of oxidising agents and prophylactic administration of NAC showed a lower incidence of acute renal damage after using contrast agents. METHODS: We analyzed 100 patients consecutively undergoing coronary angiography and/or transluminal angioplasty: the study group was given NAC orally at a dose of 600 mg twice daily, on the day before and on the day of administration of the contrast agent, together with hydration, while the control group was given only the hydration protocol with hypotonic saline. RESULTS: Twenty patients had baseline serum creatinine concentrations > 1.2 mg/dL (mild renal insufficiency group). The mean dose of contrast agent (Iodixanol; Visipaque 320, Nycomed) was 203 mL/procedure, with no statistical difference between groups. Among the patients with normal renal function, 5.7% in the NAC group and 8.8% in the control group had baseline serum creatinine concentrations above 0.3 mg/dL after 48 hours (p=NS). In patients with mild renal failure, 16.6% in the NAC group and 0% in the control group had serum creatinine concentrations > 0.5 mg/dL at 48 h (p=NS). We found no significant differences in serum creatinine values at 48 hours vs. baseline in anyone (NAC group with normal renal function or mild renal insufficiency, control group with normal renal function or mild renal insufficiency). Similarly, serum creatinine values at either baseline or after 48 hours were not significantly different in patients with normal renal function (NAC vs. control group) and with mild renal failure. CONCLUSIONS: Our study showed no potential advantage in the prevention of acute nephropathy, induced by high volumes of contrast agent, through the administration of NAC in patients with normal renal function and mild renal failure. However, the NAC dose used in our study might not be sufficient in balancing the contrast agent volume employed in these procedures.

[Inadequate treatment and control of arterial hypertension in patients with type 2 diabetes mellitus]. / L'ipertensione arteriosa non e' adeguatamente trattata e controllata nei pazienti con diabete mellito di tipo 2.

BACKGROUND: Aim of this study is to evaluate the treatment and control of arterial hypertension in patients with type 2 diabetes. METHODS: We identified 5815 diabetic patients in our health-care district (191,568 inhabitants) through prescriptions for insulin and/or hypoglycaemic drugs in the first 6 months of 2000; 3810 of them (65%) also had prescriptions for antihypertensive drugs. We evaluated a randomly selected sample of 171 patients with type 2 diabetes, 100 of whom were receiving antihypertensive drugs (94 males and 77 females, mean age 66.6 +/- 8 years, mean diabetes duration 12+/-9 years). RESULTS: Fifty-seven out of 71 patients not treated with antihypertensive drugs (80.3%) had a BP = 130/85 mmHg; 24.4% of them had a diastolic BP = 85 mmHg and 79% had a systolic BP = 130 mmHg. Thirteen out of 100 treated patients (13%) had a BP < 130/85 mmHg. Among the patients treated with antihypertensive drugs 36% received one drug, 36% two drugs and 28%=3 drugs; mean 1.98 +/- 0.9 drugs/patients. Among the patients treated with monotherapy 36.1% received ACE-inhibitors, 36.1% dihydropyridinic calcium-antagonists, 11.1% alpha-blockers, 11%, diuretics, 2.8% non-dihydropyridinic calcium-antagonists, and 2.8% angiotensin II antagonists. Patients treated with two antihypertensive drugs received more frequently an ACE-inhibitor plus a diuretic (31%) or an ACE-inhibitor plus an alpha-blocker (23%) or an ACE-inhibitor plus a dihydropyridinic calcium-antagonists (20%). A diuretic was used in 40% of the patients with two antihypertensive drugs and in 78% of those with >= 3 drugs. CONCLUSIONS: Many hypertensive type 2 diabetic patients are left untreated and only a minority of those treated reach optimal blood pressure control. The importance of an elevated systolic pressure is underestimated, and the number of antihypertensive drugs prescribed is suboptimal.

[Organohalogen contamination of a dialysis-water treatment plant]. / Contaminazione da organo-alogenati di un impianto di trattamento di acqua per dialisi.

On March 2001 the regular quality control test of the water used for dialysis in an urban centre using a reverse osmosis system revealed a high level of organo-halogenated contamination. The compounds implicated were: trichloroethylene (trielene) [M.Wt. 131 D], tetrachloroethylene, trichloromethane (chloroform) [M.Wt. 121 D], chlorodibromomethane. The dialysis unit was closed. Water samples were analysed in duplicate. The table shows the values (in ppm or microgram/l) obtained for chloroform at the given times: March 8th, altered sample; March 12th, confirmation sample; March 16th, after osmosis membranes change; March 22nd, after carbon filtration replacement; March 26th, after softener resins substitution. The AAMI doesn't recommend any value for organo-halogenated compounds in dialysis water. In the past, the European Pharmacopoeia and the Italian Health Ministry released some reference values for tap water, values which were extended to water used for dialysis. The values are 1 ppm as reference value, 30 ppm as maximum accepted value for the sum of all organo-halogenated compounds, and 10 ppm as the recommended value. In conclusion, the problem was solved by progressive replacement of the components of the water treatment system, even though the real cause remained undetermined. No clinical symptom was recorded and no level of chloroform or trielene was detected in patients' sera despite the low molecular weight and low protein binding of the compounds. A strict control of the water quality and a more comprehensive and updated reference guide are needed for better and safer dialysis delivery.

[Microbiological evaluation of two different disinfection protocols of a new hemodialysis monitor with an ultrafilter]. / Valutazione microbiologica di due diversi protocolli di disinfezione di un nuovo monitor di dialisi dotato di ultrafiltro sul dialisato.

BACKGROUND: Hemodialysis monitors represent a frequent site for bacterial contamination. METHODS: Two different disinfection protocols on a new device (Formula(R), Bellco) have been compared: only chemical or chemical plus heat disinfection by means of CFU, and LAL test. The endotoxin removing capacity of ultrafilter was tested with varying lipopolysaccharide concentrations. RESULTS: Similar results were obtained with heat disinfection compared to chemical disinfection (CFU and LAL test). The LAL test (chromogenic and gel-clot) showed that the ultrafilter performance decreased with use and was significant after 200 operating hours. CONCLUSIONS: Heat disinfection between dialysis shifts and chemical disinfection at the end of the day exclude bacterial contamination of the monitor as well as chemical disinfection; LAL test is a useful and simple tool to assess the ultrafilters performance in each Center.

[Biopsy experience at the G. Bosco Hospital from 1996 to 1999]. / Esperienza bioptica dell'Ospedale G. Bosco dal 1996 al 1999.

BACKGROUND: Aim of this study was a retrospective analysis of the renal biopsies performed in our Division. METHODS: Since January 1, 1996 to September 30, 1999 289 biopsies were performed on native kidneys, 90 patients were older than 65. RESULTS: The most frequent nephropathy was IgA glomerulonephritis (IgAGN) (28%), followed by membranous glomerulonephritis (MGN) (11%). In patients older than 65, the most frequent was MGN (20%), followed by IgAGN (12.2%). The total complications were 84 (29.1%) (hematomas >3 cm 1%; blood transfusion: 1.4%). Complications were not related to age, blood pressure, renal function, clinical presentation, number of shots. In 217 patients, the results obtained with two different modalities were compared: manual system (needle size=15 gauge) and automatic system (18 gauge). No statistically significant differences were found as regards the number of shots for single biopsy, number of glomeruli and major complications (1.6% vs 1.3%), while minor complications were more frequent in the second group. CONCLUSIONS: In conclusion, the number of renal biopsies performed in our Division has been increasing year after year. This trend can be partially explained by our wider indications to renal biopsy in elderly population (the data related to resident population showed the greatest prevalence of biopsies in patients 70 to 79 years old). Renal biopsy actually represents a safe examination even in elderly patients. From a technical point of view, on the basis of personal experience, 18 gauge acecut automatic needles seem to be preferred to other kind of devices.

Verapamil versus amlodipine in proteinuric non-diabetic nephropathies treated with trandolapril (VVANNTT study): design of a prospective randomized multicenter trial.

Angiotensin converting enzyme inhibitors (ACEI) are the most effective antiproteinuric agents and should be used as first-line drugs in both diabetic and non-diabetic proteinuric nephropathies. The role of calcium channel blockers (CCB) is much more controversial. In diabetic patients verapamil and diltiazem seem more effective than dihydropyridines in reducing urinary protein excretion, and have additive effects with ACEI, but little is available on chronic treatment of non-diabetic nephropathies for non-dihydropyridine CCBs. To test whether the combination of verapamil 180 mg or amlodipine 5 mg with trandolapril 2 mg reduces urinary protein excretion more than trandolapril 2 mg alone, we planned a prospective, randomized, double-blind, multicenter trial. The secondary aims are to evaluate the effects of both treatments on the selectivity of proteinuria and check their safety. Consecutive patients aged between 18 and 70 years with non-diabetic proteinuria > or =2 g/24 h and plasma creatinine < 3 mg/dl or creatinine clearance > or = 20 ml/min are asked to participate. After a four-week run-in during which previous antihypertensive therapy is withdrawn, a single dose of trandolapril 2 mg is given once a day in open conditions for four weeks. At the end of this period patients are randomly assigned to receive once a day, in a double blind fashion, either trandolapril 2 mg and verapamil 180 mg [plus a placebo], or trandolapril 2 mg plus amlodipine 5 mg. They are monitored after one, two, five and eight months.

Sympathetic nervous system and chronic renal failure.

The aim of this work was to review evidence on the role of the sympathetic nervous system (SNS) in chronic renal failure (CRF). Three main points are discussed: 1) SNS and pathogenesis of arterial hypertension; 2) SNS and cardiovascular risk; 3) implication of SNS in arterial hypotension during hemodialysis. Several lines of evidence indicate the presence of a sympathetic hyperactivity in CRF, and its relationship with arterial hypertension. It is suggested that diseased kidneys send afferent nervous signals to central integrative sympathetic nuclei, thus contributing to the development and maintenance of arterial hypertension. The elimination of these impulses with nephrectomy could explain the concomitant reduction of blood pressure. Several experiments confirmed this hypothesis. Regarding SNS and cardiovascular risk, some data suggest that reduced heart rate variability identifies an increased risk for both all causes and sudden death, independently from other recognized risk factors. Symptomatic hypotension is a common problem during hemodialysis treatment, occurring in approximately 20-30% of all hemodialysis sessions and is accompanied by acute withdrawal of sympathetic activity, vasodilation and relative bradicardia. This reflex is thought to be evoked by vigorous contraction of a progressively empty left ventricle, activating cardiac mechanoceptors. This inhibits cardiovascular centers through vagal afferents, and overrides the stimulation by baroreceptor deactivation. Alternative explanations include cerebral ischemia and increased production of nitric oxide, which inhibit central sympathetic activity. It is hoped that therapies aimed at modulating sympathetic nerve activity in patients with CRF will ameliorate their prognosis and quality of life.

[Spiral x-ray computed tomography in the diagnosis of central venous catheterization complications]. / Contribution de la tomodensitométrie spiralée dans le diagnostic des complications du cathétérisme veineux central.

In this work we report our initial experience on the utilisation of the spiral tomodensitometry in the study of the vascular complications due to the catheterization of the internal jugular vein. We present the results of a systematic search of vascular lesions after removal of an indwelling catheter in a group of 18 patients and describe a few cases of acute complications where the use of TDMS has been very useful in the diagnostic workout. The results confirm the risks associated with the catheterization of the internal jugular vein, showing a frequency of lesions of various degree in about 50% of the cases. Moreover, we discuss some aspects of the thrombotic complications in the patients carrying a central venous catheter and the advantages of the diagnostic application of the spiral tomodensitometry.

Dialock(R)subcutaneous port for hemodialysis: A twelve-month experience in a single center.

Background.The arteriovenous fistula (AVF) is still considered the golden standard form of vascular access for hemodialysis. However, the increasing use of central venous catheters mirrors the growing difficulty in planning an AVF. A totally implantable new device, the Dialock(R)system (Biolink Corporation, Norwell, MA), allowed us to conduct the first Italian experience. Methods.From February 1st 2000 to January 31st 2001, we implanted 21 devices in 12 males and 9 females, median age 66+/-12 years, with a dialysis duration ranging from 0 to 22 years. In 6 cases the Dialock (R)was first choice access, in 5 it replaced a malfunctioning tunneled central venous catheter, and in 10 cases it was the rescue access after previous AVF failures. Results.On average, the device was accessed 3.5 days after implantation. Median duration of use was 142 days (range 29-365), for a global observation period of 118.2 pt-months. Nineteen devices are currently working with-out any problem. One port was removed after 60 days due to thrombosis, and another after 9 months of use due to sepsis. Another patient had a systemic infection with cardiac and vertebral involvement with complete remission after 4 months of antibiotic therapy and salvage of the device. The infection rate was 1.3 per 1000 catheter-days. Prescribed blood flow was achieved in 95.7% of the sessions. Conclusion.Our short-term results confirm the efficacy and reliability of the new device. In order to assess the true indication for implanting Dialock(R), a more prolonged observation period is needed.

IL-10 stimulates production of platelet-activating factor by monocytes of patients with active systemic lupus erythematosus (SLE).

IL-10 displays modulatory properties on the synthesis of platelet-activating factor (PAF), a potent inflammatory mediator of vascular injury. Despite the fact that IL-10 is considered to be an anti-inflammatory cytokine, IL-10 levels correlate with disease activity in SLE. Moreover, in SLE IL-10 is unable to exert its immunosuppressive and anti-inflammatory effects. We have investigated the ability of IL-10 to stimulate PAF production from monocytes of SLE patients. Spontaneous and IL-10-stimulated PAF production by peripheral blood monocytes was measured in active (n = 13) and inactive (n = 14) SLE patients and in 15 normal control subjects. We observed that monocytes derived from patients with active SLE, but not from controls or inactive SLE, spontaneously produced significant amounts of PAF. Moreover, IL-10 enhanced the synthesis of PAF from monocytes of active SLE patients only. IL-10-induced PAF production correlated with the severity of the disease and with the extent of proteinuria. These results indicate that IL-10 only stimulates the synthesis of PAF from monocytes of SLE patients when immunologically active, suggesting that IL-10 may possess a paradoxical proinflammatory effect in SLE by promoting the production of PAF, a secondary mediator of inflammation.