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PurposeThe aim of the study was to assess whether a history of dialysis is related to cardiopulmonary resuscitation (CPR) attempts and survival to hospital admission in patients with out-of-hospital cardiac arrest (OHCA).MethodsThe databases of the POL-OHCA registry and of emergency medical calls in the Command Support System of the State of Emergency Medicine (CSS) were searched to identify patients with OHCA and a history of dialysis. A total of 264 dialysis patient with OHCA were found: 126 were dead on arrival of emergency medical services (EMS), and 138 had OHCA with CPR attempts. Data from the POL-OHCA registry for patients with CPR attempts, including age, sex, place of residence, first recorded rhythm, defibrillation during CPR, and priority dispatch codes, were collected and compared between patients with and without dialysis.ResultsCPR attempts by EMS were undertaken in 138 dialyzed patients (52.3%). The analysis of POL-OHCA data revealed no differences in age, sex, place of residence, first recorded rhythm, and priority dispatch codes between patients with and without dialysis. Defibrillation was less frequent in dialysis patients (P = 0.04). A stepwise logistic regression analysis revealed no association between survival to hospital admission and a history of hemodialysis (odds ratio = 1.12; 95% CI 0.74–1.70,P = 0.60).ConclusionsA history of dialysis in patients with OHCA does not affect the rate of CPR attempts by EMS or a short-term outcome in comparison with patients without dialysis. Defibrillation during CPR is less common in patients on dialysis than in those without.

Stopping dialysis, as a cause of death is common, particularly in North America. In the USA it is now the third most common cause of death in dialysis patients, and in Canada the second most common cause, after vascular deaths, as illustrated in Figure 1.

Long before the routine use of dialysis, patients dying of uremia were found to have a high incidence of gastrointestinal abnormalities (1). This chapter will address issues relating to the digestive system in dialysis patients, with an emphasis on conditions that affect these patients more commonly than the general population. Improvements in dialysis technique and changes in the patient population undergoing dialysis have modified the spectrum of gastrointestinal diseases seen in patients with end-stage renal disease (ESRD), so the more recent literature will be emphasized

Viral liver diseases, especially due to hepatitis B virus (HBV) and hepatitis C virus (HCV), were observed with a high frequency in hemodialysis units throughout the world. Due to the deficient immune response of uremic subjects, which renders them unable to eliminate viruses, hemodialysis patients act as reservoirs of the viruses and transmit infection to other patients, to the dialysis unit staff and eventually to their own family, in the case of infection with HBV.

This chapter is an update of the excellent one written by Jennekens and Jennekens-Schinkel in the previous edition of this textbook. Although there has been no breakthrough in the understanding of the neurological problems occurring in dialysis patients, the management of neurological patients has changed during the past few years, making it necessary to revise this chapter. Neurological complications in dialysis patients are common and diverse. Some relate to persistence of mild uraemia others complicate the dialysis procedure. A number of neurological disorders occur with relatively high frequency in patients requiring this form of therapy but do not relate to uraemia nor to the methods used for treatment

Most of the data concerning survival of patients treated with maintenance dialysis therapies for end-stage renal disease (ESRD) published in the literature over the years are limited to up to 5–7 year survival after commencement of renal replacement therapy (RRT). This is true in particular for the data released on regular time-intervals through national or international renal data Registries such as the Registry of the European Dialysis and Transplant Association (EDTA-ERA) (1, 2, 3) or the United States Renal Data System (USRDS) (4), the Canadian Organ Transplant Register (5) or the Australia and New Zealand Dialysis and Transplant Registry (6). Comprehensive data relating to long-term survival for dialysis patients (10 or more years post start of treatment) are scarce (1) and usually display the experience of individual dialysis centres (7, 8, 9, 10, 11) or that of a small number of dialysis units operating within a limited geographical area (12). Overviews concerning experiences of very long survival on dialysis have also been reported on, or by, individual patients taken onto RRT during the early years of development of maintenance dialysis as a life-sustaining therapy for ESRD (13, 14, 15, 16).

‘Telemedicine’ is the remote consultation between physician and patient by means of videoconferencing, but broadly could apply to the gathering of electronic information at the bedside by remote devices, such as wireless Internet connection to sites with medical informatics. Both systems will be described in this subchapter. Currently telemedicine is quite short of superseding the telephone and email, by which dialysis patients communicate with their physicians, but recent changes in informatics and communications devices will likely lead to more widespread use of telemedicine. Compared to a year ago the number of Internet sites with the word ‘telemedicine’ has risen from about 250,000 to 500,000 (using the Internet search engine Google®); 12,800 sites with the terms ‘telemedicine dialysis’ were also found. At the time of writing in the National Library of Medicine database (1) there were 6303 publications on telemedicine, 29 of which were on telemedicine and dialysis.

Most nephrologists are primary health-care providers for patients receiving renal replacement therapy (1). Gastrointestinal symptoms are among the commonest complaints in this population with 79% of dialysis patients having at least one chronic gastrointestinal symptom (2). This chapter will provide an overview of gastrointestinal disorders and liver disease in end-stage renal disease (ESRD).

The burden of illness due to cardiac disease in chronic uremia is high. The cardiac death rate has been reported as 104/1000 patient-years in the USA, and cardiac disease accounted for 45% of all deaths (1). When compared to the general population the annual cardiovascular death rate for dialysis patients is substantially higher in all age groups, particularly at younger ages (Figure 1) (2). Indices of morbidity are also high. The prevalence of clinical manifestations of cardiac disease on initiation of end-stage renal disease (ESRD) therapy is high (3–5) (Table 1). The probability of having a myocardial infarction or angina requiring hospitalization in hemodialysis patients is 10% per year (6).

Aside from the organic uremic toxins it has become evident during recent decades that inorganic solutes may also be responsible for some of the symptomatology of the uremic state. Hence, interest in trace element accumulation/deficiency and the potential toxic consequences of disturbed concentrations of these substances has grown rapidly (1).

The prevalence of end-stage renal disease (ESRD) has increased dramatically during the past two decades, resulting in over 230,000 dialysis patients in the United States alone by 1998 (1). The need for therapeutic advances in dialysis therapy is underscored by the high rates of morbidity and mortality in this population. Fortunately, the progress of observational research for patients receiving dialysis therapy has been extensive, including the development and widespread utilization of national databases for ESRD. Observational studies have provided much information regarding the associations among numerous variables in dialysis populations, and have in many instances led to changes in clinical practice. However, the possibility of bias is difficult to rule out in observational studies of dialysis patients just as it is in other areas of biomedical research, and in most cases randomized clinical trials are required to definitively establish the effects of treatments on patient outcome.

Viral hepatitis B and C are among the most important infectious challenges for dialysis patients. The blood-borne viruses HBV and HCV can easily be communicated in the epidemiological setting of a dialysis center since susceptible patients are treated in centers together, using extracorporeal devices and access to the blood. This situation is further aggravated by the influence of uremia on immune function of dialysis patients, which renders many patients incapable of eliminating viral infections. The presence of chronically infected persons needing regular vascular access for dialysis enhances the risk of virus transmission.

Atherosclerosis is a slow, complex process in which lipids, cholesterol, calcium and other substances are accumulating in the endothelium of the arterial wall. These deposits stimulate the artery wall cell to produce substances that lead to further thickening of the endothelium. In consequence the artery’s diameter shrinks, ultimately resulting in clinically evident vascular disease.

Hemodialysis is the treatment that sustains the life and health of more patients with end-stage renal disease (ESRD) than any other therapy. There are approximately 232,000 people in the United States who receive this treatment, representing 89.5% of US dialysis patients (1). Most of these come to dialysis centers three times each week, where a multidisciplinary professional staff assesses their clinical status, and prescribes and administers dialysis and related therapies. The lifelong dialysis need, the frequency of treatment, and the need for patients to integrate dialysis into the fabric of their lives all make dialysis facilities somewhat unique in the medical care system. Patients often relate with dialysis staff more frequently and more intensely than they do with their family or close friends.

In the preceding chapters the relationship between ‘volume’ and blood pressure has been mentioned several times. We will now discuss this and other factors involved in dialysis hypertension in more detail.

While hypertension occurs in ±15% of a normal population, its frequency is much higher in patients with renal disease. Roughly speaking the incidence increases in parallel with progression of renal failure, and by the time dialysis treatment is started, up to 90% of the patients are hypertensive. The appearance of hypertension is related to the nature of the renal disease. It is most frequent — and may start before functional impairment — in various glomerular diseases and polycystic kidneys, while its onset is later in primary tubular and interstitial disorders. This difference is probably due to differences in salt excretion impairment and/or in activity of the renin-agiotensin system. Once the patient has become anuric, the relation of BP to the underlying disease is less clear, but this subject has not been sufficiently analyzed.

A newly appointed junior staff member of a large nephrology physicians group in a community hospital indicates his dissatisfaction with the system of referrals. He notes that after stabilizing newly evaluated kidney failure patients, continuing long-term care is arranged with one of several surrounding free standing dialysis units. The unit selected for transfer of the new patient is a proprietary facility owned by a partnership held by three of the senior renal staff members. The same physicians who referred the patient and own the unit then decide on the length of each dialysis treatment as well as other components of care such as whether or not to do nerve testing for a fee. Profits at this dialysis unit become the personal income of its owners. Concerned over abrogating his patient’s free choice, the junior nephrologist indicates his intention to resign from the group.

Commonly an individual is designated as elderly at 65 years. During this century the number of people living beyond age 65 has increased. In 1900 only 4% of the Western world’s population was over 65 years of age, but now this fraction is 12% and rising [1]. By the year 2040, 21% of the population in the United States will be over 65, and by the year 2050 one in 20 people in the USA will be older than 85 [2, 3]. This progressive increase in the elderly and the success of dialysis have produced a dramatic increase in the numbers of elderly dialysis patients worldwide. Thus, in the USA 47% of those on dialysis are over 65; this fraction is expected to increase to over 60% by the end of this century [4–6]. In Canada, in 1989, 35% of end-stage renal disease (ESRD) patients were over the age of 65 compared to 25% in 1981 [7]. In 1990, in a UK dialysis centre that provides the sole nephrological service for a population of 1.2 million people, those over 65 constituted more than 25% of all new patients accepted for dialysis [8]. The European Renal Association Registry has reported a similar trend. In 1977 only 9% of those patients starting renal replacement therapy were older than 65 years; in 1980, 11%; in 1983, 30%; whereas by 1992 this population had increased to nearly 37% [9, 10]. Thus, elderly patients, who previously were excluded from dialysis, now are the fastest-growing segment of the dialysis population [10, 11].

Anennia is an alnnost universal feature of end-stage renal failure and an important contributor to the complaints of these patients. In addition observational studies have identified anemia as an important independent risk factor for general and cardiovascular mortality in dialysis patients. Anemia is — together with hypertension — a major determinant of myocardial dysfunction, and in one study it appeared to be independently associated with left ventricular dilatation and the development of de novo cardiac failure.

Cardiac disease is the major cause of death in dialysis patients, accounting for half of the total mortality. Clinical manifestations (morbidity of cardiac disease) are equally high. When routinely assessed by echocardiography, the proportion of patients with abnormal dimensions of cardiac compart-ments is still higher. It should be remarked that this also applies to patients with chronic renal disease. In other words the sanne pathogenetic mecha-nisms are present before the start of dialysis treatment. Many patients entering dialysis programs have severe damage already and the complica-tions seen during HD treatment are the result of an ongoing process. Unfortunately, some authors consider it as inexorable fate and speak about the natural history of cardiac disease in dialysis patients. This suggests that the development is the result of sonne intrinsic cardiac process, while in reality its course is mainly determined by extrinsic factors, i.e. the way of treatment. Dialysis provides a unique opportunity to correct some of these pathogenetic mechanisms and thus slow down, improve, or even cure complications, which once were considered inevitable.

The cardiovascular complications remain an important cause of morbidity and mortality in dialysis patients and in the long term outcome of the kidney transplant recipients. Lipoprotein(a) [Lp(a)]: which concentrations are often raised in dialysis patients, is recognized as an independent risk factor for atherosclerosis, particularly when its level reaches 30 mg/dl.

Cardiac and vascular disease is the major cause of morbidity and mortality in dialysis patients. Hypertension, lipid disturbances and uremic toxicity play a key role in the pathogenesis of cardiovascular disorders. Overall, cardiac complications account for 40% of deaths in dialysis patients and up to 50% when adding cerebrovascular accidents (Figure 8-1).

Survival of patients on dialysis therapy for end-stage renal disease (ESRD) has been a main concern of nephrologists and physicians [1’9]. The steady increase in continuous ambulatory peritoneal dialysis (CAPD) patients made it possible to compare outcomes of CAPD patients and hemodialysis patients. The United States Renal Data System (USRDS), established in 1988, has begun to supply excellent-quality statistics on dialysis therapy. Analysis of these data revealed many determinants in morbidity and mortality of dialysis patients: dialyzer reuse, duration of dialysis, quality of dialyzer membranes, causes of ESRD, availability of transplantation, and the age distribution of background population.

Previous comparisons of the survival of end-stage renal disease (ESRD) patients in the US with Europe and Japan indicated worse survival outcomes for the US, with adjustment for differences in age and diabetes [1]. A similar set of survival comparisons between Japan and the US was presented at a recent conference in New York [2] (April 26, 1993) for a newer cohort of incident patients treated with continuous ambulatory peritoneal dialysis (CAPD) and hemodialysis (HD). This report summarizes the results of those across-country comparisons, with added consideration given to the expected survival of dialysis patients compared to the expected survival of the general population in both societies.

The leading causes of morbidity and mortality in patients with end stage renal disease (ESRD) who are treated by maintenance dialysis include cardiovascular diseases, renal osteodystrophy, infections (vascular access related and other systemic), and inadequate dialysis delivery. Many recent publications have focused on these issues, demonstrated various parameters to identify indices for poor patient survival, and have outlined steps to reduce morbidity and mortality [1–6]. One issue which has not received much attention is the role of, or lack thereof, patient’s participation in his own care, and adherence to prescribed treatment regimen, in contributing to morbidity and mortality. Many urban dialysis centers are obliged to care for an increasing number of patients with renal failure who are intravenous drug addicts (IVDA), infected with the Human immunodeficiency virus (HIV), prisoners, undocumented aliens, homeless individuals, indigent patients with little or no family support. In such a clinical setting, noncompliance to prescribed therapy due to a variety of reasons is another major factor in limiting the ability of nephrologists to achieve the goals of renal replacement therapy in ESRD subjects.

International comparisons of survival of dialysis patients have become popular [1–4]. Such comparisons have been used to evaluate differences in the procedure of hemodialysis. In general, the conclusions have been that short dialysis (independent of Kt/V values), low Kt/V values, the procedure of re-use of dialyzers, or non-compliance by patients, are responsible for the fact that survival is best in Japan, second-best in Europe, and lowest in the US [1–4]. There are many factors that influence mortality of dialysis patients (Table 1). Many are subjects of controversy even in single factor analyses. The interaction of many such factors is virtually unknown.

There are four major factors that affect survival of dialysis patients. They are: 1) the dose of dialysis 2) protein and calorie intake 3) smoking and 4) control of blood pressure. In the current dialysis literature most publications deal extensively with the dose of dialysis and to a somewhat lesser extent, the nutrition of the patient. In contrast, virtually no current meetings or publications deal with the ill effects of smoking and hypertension as risk factors that have a strong adverse effect on the survival of dialysis patients. Two examples: a review of the table of contents of this volume will reveal that the topic is not addressed in a separate presentation; a supplement to the Feb. 1993 issue of Kidney International contained 15 manuscripts from an excellent international meeting comparing the results of hemodialysis and peritoneal dialysis. None of the manuscripts dealt with the subject of control of hypertension.

It seems agreed that annual mortality rates for dialysis patients reflect a considerable range from unit to unit, doctor to doctor, region to region and country to country. The US, starting late in its distribution efforts, without a system for universal health care, has done a remarkable feat in enabling close to 200,000 uremic patients to survive on dialysis at a unit cost which has steadily declined since 1973. Nothing else procured by our Government has declined in cost during those inflationary years. Moreover, the transplant rate has been the envy of many, limited mainly by the supply of organs and catering to many foreign-born nationals in the process.

Hemodialysis was first performed in the home in 1964 and 1965 [1,2]. Advantages of cost [3], convenience and enhanced survival [4] were rapidly associated with home hemodialysis. This treatment grew to encompass 42% of all patients in the United States treated for end stage renal disease [5]. In areas of strong advocacy by Nephrologists such as Seattle, the percentage of patients on this therapy was even higher. Shortly after Medicare assumed funding for most treatments of dialysis patients, home hemodialysis began a decline which has continued to the present. Currently less than 2% of the US popuilation is treated in this way [6].

In the United States and many other countries, the number of elderly ESRD patients treated by dialysis continues to increase. Many of these receive treatment for a relatively short time before they die. Our own analysis of factors related to survival on dialysis of 1354 black and 965 white patients, who began treatment during 1982–1986 at age 60 or older, showed median survival times of only 2.7 years for black patients and 1.7 years for white patients [1]. Data reported by Neu and Kjellstrand [2] and by Eggers [3] indicate that elderly patients are significantly more likely to withdraw from dialysis than are younger patients, raising questions about the value that elderly persons attribute to life on dialysis. As Marai et al. have noted, “with the shorter life expectancy in the elderly, particularly in the group over 65 the ‘quality of life’ provided by dialysis is particularly relevant…” [4]. We investigated the quality of life of elderly dialysis patients, using responses from a large probability sample of older patients living in the southeastern United States, and will discuss the relation of demographic variables, health status, and dialysis treatment modality to patients’ quality of life responses.

A common cause of death in dialysis patients in North America is the stopping of dialysis. In Canada, approximately 20% of such deaths are due to discontinuation of treatment, second only to cardiac events, which are responsible for 35% of all deaths. In the USA, stopping dialysis is responsible for approximately 15% of deaths, secondary to cardiac causes — 50% — and infection — 20% [1, 2]. Australia [3] reports similar figures, but figures from Europe are lower [4]. In the West, stopping treatment is directly related to age, while in Japan [5] it is inversely correlated with age (Fig. 1).

This chapter will explore three major questions: in general, what is the current state of the law on termination of treatment decisions as we begin the 1990s, what is the current law on stopping treatment in dialysis patients, and what are the unique features of stopping dialysis that make these decisions more, or less, legally problematic?

Stopping dialysis, as a cause of death is common, particularly in North America. In the USA it is now the third most common cause of death in dialysis patients, and in Canada the second most common cause, after vascular deaths, as illustrated in Figure 1.

Chronic hemodialysis started in Iran in 1967. In 1967 an End Stage Renal Disease (ESRD) office was established in the Ministry of Health to cover dialysis expenses for all patients throughout the country (1). The result was that the rate of acceptance of new dialysis patients steadily increased from 179 (5.3 per million) in 1976 to 1060 (21 per million) in 1989. The total number of dialysis patients also rose during this period. At the end of 1980 a total of 700 patients (16 per million) were being dialysed throughout the country, which increased to a total case load of 3100 (62 per million) patients by the end of 1989.

This form of dialysis became freely available in 1980. There has been a substantial increase in use of this technique, interest in the procedure and development of biomedical expertise in continuous ambulatory peritoneal dialysis (CAPD). Approximately half of the dialysis patients in Britain receive this form of treatment; world wide the figure is between 15 and 20 per cent. Long-term results are as good as those for haemodialysis or transplantation. Because of CAPD many people are dialysed who previously would not have received treatment.

The association of aluminum toxicity on the development of osteomalacia and aplastic bone disease in dialysis patients is a subject of major research interest. To study the adverse effect of aluminum on bone, experimental animal models of aluminum induced bone disease have been developed. Although an exact duplication of the bone disease observed in dialysis patients has not been achieved, morphological changes resembling those observed in patients have been produced in the various experimental models of aluminum intoxication. The importance of these animal models is not that they accurately reproduce the disease but that they are useful in studying the mechanisms of bone aluminum toxicity.

Clinical and other biochemical studies of trace metals depend upon accurate and precise methods of analysis. A review of the history of aluminium-related diseases [1] indicates that it was the measurement of aluminium in brain and other tissues that led to the proposal that this metal was a causative agent responsible for the condition now recognised as dialysis encephalopathy [2]. An early study showed that the bones of Newcastle dialysis patients contained both an excess of aluminium and an excess of fluoride compared with patients who had been dialysed in other treatment centres [3]. Likewise, it was the discovery of high aluminium concentrations in the water supplies of geographical areas coincident with the dialysis centres with the greatest incidence of dementia and dialysis osteodystrophy that provided crucial evidence in identifying the major source of aluminium exposure for haemodialysis patients [4].

Everyone involved with dialysis patients knows that the treatment can be very stressful, for some more than others. Many patients have difficulty in adapting to their new way of life. There are the often unspoken fears regarding earning capacity, length of artificially prolonged life and the uncertainties of waiting for a transplant kidney.

Visual complaints are frequent in dialysis patients, especially at the onset of chronic haemodialysis treatment. Many experience visual disturbances or headache, that usually are not due to a disequilibrium syndrome, causing a relative increase of intraocular pressure. In some patients these complaints do not disappear, returning during each individual dialysis session.

Dialysis and transplantation greatly prolong the life of patients with chronic renal failure. Neurological problems in dialysis patients have slowly changed as complications have been recognized, studied and consequently prevented or treated. Reviews of the neurological complications of chronic renal disease from the early sixties stress problems which are not seen frequently today (1). Increased knowledge has slowly shifted the emphasis to prevention of such problems.

CAPD has become an accepted alternative form of therapy for patients with end-stage renal disease. Rapid expansion in the number of dialysis units with experience in this form of therapy is occurring. As of Fall 1980, 261 dialysis facilities in the United States and an approximate equal number throughout the world have made CAPD available to most patients (Figure 1). An increase in this patient population is continuing and more than 2000 patients (near 2 to 3% of the dialysis patients in the USA) are presently undergoing CAPD (Figure 2).

Today, throughout the world, close to 100,000 patients with end-stage renal disease are kept alive by maintenance hemodialysis therapy (1). As health care workers, it is incumbent upon us to be familiar with the many facets of this ubiquitous therapy. Important technical information such as selection of equipment for hemodialysis (dialyzers, monitors, etc.) is discussed elsewhere in this book. This chapter addresses the problems of when to initiate dialysis therapy, how to select a schedule, and special precautions and considerations for high risk patients. In addition to providing a scheme for routine monitoring of dialysis patients it also gives an assessment of 10 (or more) years veterans of dialysis.

Prior to the advent of chronic hemodialysis, infection was frequently a terminal or preterminal event in patients with end-stage renal failure. During the last decade, better hemodialysis techniques coupled with general advances in medical therapy have improved the prognosis (1–3). However, infectious complications continue to be a major medical threat to patients receiving maintenance hemodialysis (4–7). It is unquestionable that the most common type of infections are those related to the blood access device. In this chapter we will review incidence and type of infectious complications that occur in patients undergoing chronic hemodialysis, both as documented in the literature and as determined by us in a survey of 445 patients. It seems important to emphasize at the beginning that most of the infections seen in patients with severe renal failure can be accounted for by commonly occurring bacteria and not by unusual or opportunistic organisms. The repetitive exposure of these patients to infectious risk factors during hemodialysis appears of major importance in determining the infectious complications observed.

The prime aim of haemodialysis for chronic renal failure is to rehabilitate the patient to as normal a life as possible. This means restoring him to the life style he could reasonably expect had he not developed end stage renal disease. Such a life style includes the ability to travel either as a requirement of employment or for vacational purposes. The ability to travel is becoming increasingly important in many occupations and vacational travel, particularly to other countries, is increasing in popularity. Treatment by intermittent haemodialysis places a restriction on travel for most patients and this may provide a source of frustration to themselves and their families. There is, therefore, a strong need to provide facilities for both travel and holidays for dialysis patients and their families.

Surgical considerations are of fundamental importance in the success or failure in both dialysis and transplantation. Dialysis patients’ lives often depend on the adequacy of their shunts or fistulas. Creation of an arteriovenous fistula is the most important surgery they undergo: it is their lifeline to the dialysis machine.

In 1965 the number of regular dialysis patients notified to the EDTA for the whole of Europe was 160. By 1971 this number had risen to 7000 and by 1975 it exceeded 22 000. This dramatic rise has led to logistic and financial problems which have been tackled with varying degrees of success in the different European countries.

Osteomalacia renal osteodystrophy in patients on long-term hemodialysis has been associated with aluminum accumulation in bone (Ho82). Aluminum has been shown to be localized at the mineralization front in dialysis osteomalacia, suggesting it as a possible cause of this disorder. Animal models of aluminum-induced osteomalacia have been demonstrated which mimic the clinical disease (Go, in press, Ch83). In addition, recent work has shown that aluminum had an inhibitory effect on mineralization in organ cultures of embryonic chick bone (Mi84). It has been demonstrated that aluminum exerts a significant physical chemical effect on the formation and growth of crystalline hydroxyapatite (HA) in three in vitro test systems thought to be analogous to biological mineralization (B184). This earlier study suggested that aluminum interfered with HA production in these different systems by acting as a surface poison blocking nucleation and/or growth sites on ACP and HA surfaces.

Everyone involved with dialysis patients knows that the treatment can be very stressful, for some more than others. Many patients have difficulty in adapting to their new way of life. There are the often unspoken fears regarding earning capacity, length of arti­ficially prolonged life and the uncertainties of waiting for a transplant kidney.

We have available in Italy a national registry of all dialysis and transplant patients which is run by the ‘Associazione Nazionale Emodializzati’ (ANED), the Italian association of dialysis patients. It is a very useful source of information for all surveys in this field in our country; the data are more complete than those of the EDTA registry and are very accurate, because of the direct control of the individual patient data in every single facility.