Patients surviving more than 10 years on haemodialysis. The natural history of the complications of treatment

β2-Microglobulin Elevates COL5A1 mRNA in the Subsynovial Connective Tissue of Patients Receiving Hemodialysis With Carpal Tunnel Syndrome

Background Although carpal tunnel syndrome (CTS) is frequently observed in patients undergoing long-term hemodialysis (HD), exactly how CTS arises is unknown. Here, we examined levels of COL5A1 in the subsynovial connective tissue (SSCT) of patients receiving HD and studied its potential regulation by β2-microglobulin (Β2-MG) in SSCT-derived cells (SSCTCs). Methods We extracted SSCT samples from 67 patients with CTS (49 non-HD and 18 HD) during carpal tunnel release. The samples were subjected to quantitative polymerase chain reaction (qPCR) to determine COL5A1 expression. Further, to examine the potential regulation of COL5A1 expression by Β2-MG, SSCTCs were stimulated in the absence (control) or presence of 10 µg/ml Β2-MG. Results The HD group showed significantly elevated COL5A1 levels compared to the non-HD group (P=0.027). Moreover, treating SSCTCs with Β2-MG for 24 h increased the mRNA expression of COL5A1 relative to control conditions (P=0.013). Conclusions Elevated COL5A1 expression may form part of the mechanism underlying the development of CTS, and Β2-MG may play a role in promoting COL5A1 expression in HD patients.

Median Nerve and Ulnar Nerve Entrapment with Cubital Tunnel Syndrome in a Hemodialysis Patient Following Creation of an Arteriovenous Fistula

Neurological and vascular complications associated with creation of arteriovenous access need to be recognized promptly to deliver appropriate interventions for relief of symptoms and avoid loss of function of the involved extremity. We present here a 55-year-old female with end-stage renal disease on hemodialysis secondary to diabetic nephropathy who had a surgical creation of first stage of the brachial artery-basilic vein fistula in the left arm. She subsequently developed pain and weakness of the left arm which was diagnosed as median and ulnar nerve entrapment. She was treated with surgical nerve release and neurolysis and her symptoms improved.

New Intravenous Calcimimetic Agents: New Options, New Problems. An Example on How Clinical, Economical and Ethical Considerations Affect Choice of Treatment

BACKGROUND

Dialysis treatment is improving, but several long-term problems remain unsolved, including metabolic bone disease linked to chronic kidney disease (CKD-MBD). The availability of new, efficacious but expensive drugs (intravenous calcimimetic agents) poses ethical problems, especially in the setting of budget limitations.

METHODS

Reasons of choice, side effects, biochemical trends were discussed in a cohort of 15 patients (13% of the dialysis population) who stared treatment with intravenous calcimimetics in a single center. All patients had previously been treated with oral calcimimetic agents; dialysis efficacy was at target in 14/15; hemodiafiltration was employed in 10/15. Median Charlson Comorbidity Index was 8. The indications were discussed according to the principlist ethics (beneficience, non maleficience, justice and autonomy). Biochemical results were analyzed to support the clinical-ethical choices.

RESULTS

In the context of a strict clinical and biochemical surveillance, the lack of side effects ensured "non-maleficence"; efficacy was at least similar to oral calcimimetic agents, but tolerance was better. Autonomy was respected through a shared decision-making model; all patients appreciated the reduction of the drug burden, and most acknowledged better control of their biochemical data. The ethical conflict resides in the balance between the clinical "beneficience, non-maleficience" advantage and "justice" (economic impact of treatment, potentially in attrition with other resources, since the drug is expensive and included in the dialysis bundle). The dilemma is more relevant when a patient's life expectancy is short (economic impact without clear clinical advantages), or when non-compliance is an issue (unclear advantage if the whole treatment is not correctly taken).

CONCLUSIONS

In a context of person-centered medicine, autonomy, beneficence and non-maleficence should weight more than economic justice. While ethical discussions are not aimed at finding "the right answer" but asking "the right questions", this example can raise awareness of the importance of including an ethical analysis in the choice of "economically relevant" drugs.

Positron Emission Tomography Can Support the Diagnosis of Dialysis-Related Amyloidosis

BACKGROUND

The improvements in dialysis have not eliminated long-term problems, including dialysis-related amyloidosis (DRA), caused by Beta-2 microglobulin deposition. Several types of scintigraphy have been tested to detect DRA, none entered the clinical practice. Aim of the study was to assess the potential of PET-FDG scan in the diagnosis of DRA.

METHODS

Forty-six dialysis patients with at least one PET scan (72 scans) were selected out 162 patients treated in 2016-2018. Subjective global assessment (SGA), malnutrition inflammation score (A), Charlson Comorbidity Index (CCI), were assessed at time of scan; 218 age-matched cases with normal kidney function were selected as controls. PET scans were read in duplicate. Carpal tunnel syndrome was considered a proxy for DRA. A composite "amyloid score" score considered each dialysis year = 1 point; carpal tunnel-DRA = 5 points per site. Logistic regression, ROC curves and a prediction model were built.

RESULTS

The prevalence of positive PET was 43.5% in dialysis, 5% in controls (p < 0.0001). PET was positive in 14/15 (93.3%) scans in patients with carpal tunnel. PET sensitivity for detecting DRA was 95% (specificity 64%). Carpal tunnel was related to dialysis vintage and MIS. A positive PET scan was significantly associated with dialysis vintage, MIS and amyloid score. A prediction model to explain PET positivity combined clinical score and MIS, allowing for an AUC of 0.906 (CI: 0.813-0.962; p < 0.001).

CONCLUSIONS

PET-FDG may identify DRA, and may be useful in detecting cases in which inflammation favours B2M deposition. This finding, needing large-scale confirmation, could open new perspectives in the study of DRA.

Parathyroid Cancer in a Hemodialysis Patient: A Case Report

An extremely rare case of parathyroid cancer in a hemodialysis patient is presented here. A 69-year-old man was operated on for secondary hyperparathyroidism due to chronic renal failure. A locally invasive tumor of the right inferior parathyroid gland and enlargement of the other three parathyroid glands were found during bilateral neck exploration. Surgical management consisted of en bloc resection of the right inferior parathyroid gland with the right thyroid lobe and part of a sternothyroid muscle along with subtotal parathyroidectomy of the three enlarged parathyroid glands. Histological examination of the resected tumor provided evidence of a parathyroid cancer in the right inferior parathyroid gland. Nodular hyperplasia was confirmed histologically in the other three glands. With less than 20 previous cases described in the literature, parathyroid cancer is a very rare condition in hemodialysis patients.

Antibiotic Prescribing Evaluation in an Outpatient Hemodialysis Clinic

Background

Empiric vancomycin treatment is frequently used in hemodialysis (HD) patients because of ease of administration when methicillin-resistant Staphylococcus aureus (MRSA) infection is suspected. Differing rates of MRSA indicate that empiric antibiotic treatment should be based on a center-specific antibiogram.

Objective

To develop a center-specific antibiogram, evaluate antibiotic prescribing patterns, and determine areas of improvement in infection treatment.

Methods

The antibiogram was constructed from culture and susceptibility (C&S) data from January through December 1999. Evaluation of prescribing habits was based on 3 criteria: (1) Hospital Infection Control Practices Advisory Committee and Centers for Disease Control and Prevention guidelines; (2) vancomycin for 1 dose followed by appropriate antibiotic based on C&S results; and (3) C&S obtained with more than 1 dose of antibiotic.

Results

HD was provided to 161 patients during the study period. Antibiotics were empirically prescribed 104 times in 62 different patients. Cultures were obtained 122 times, and 67 different isolates were identified. Gram-positive organisms and gram-negative organisms accounted for 77.6% and 22.4% of isolates, respectively. Gram-positive organisms were identified as Staphylococcus spp. (53.8%); 17.9% of the staphylococcal isolates were MRSA strains. No isolates of vancomycin-resistant enterococcus were identified. Based on the antibiogram, empiric antibiotic therapy within our center should be 1 dose each of vancomycin and an aminoglycoside. Empiric vancomycin was used 71 times. When criterion I is used, 12 prescriptions (16.9%) were considered appropriate. When criterion II and adjustment for MRSA reported for our center were used, 46 (64.8%) vancomycin prescriptions were considered appropriate. Forty-one patients had more than 1 dose of antibiotic therapy, and 18 (43.9%) of those patients did not have C&S data obtained as prescribed by criterion III. Areas of prescribing improvement include obtaining a C&S in all suspected infections prior to empiric therapy and a more aggressive antibiotic switch based on C&S results.

Conclusions

Antibiograms can be used to determine appropriate empric antibiotic therapy and identify areas of improvement.

Antibiogram Development for an Outpatient Dialysis Center

Infection causes significant morbidity and mortality in end-stage renal disease patients. Despite recommendations to the contrary, vancomycin is often used empirically. Antibiograms may aid in the choice of empiric antibiotic therapy. We developed an antibiogram and determined the susceptibility of various microorganisms to cefazolin, gentamicin, and vancomycin. Retrospective review of culture results and susceptibility data from a 21-month time period were used to determine microorganism frequency of identification and antimicrobial sensitivity. A total of 362 microorganisms were identified and 285 cultures performed in 171 patients (144 hemodialysis; 27 peritoneal dialysis). Predominant organisms were coagulase-negative staphylococci (39.8%) and Staphylococcus aureus (24.6%). Gram-positive organisms accounted for 73.5% of isolates. Methicillin-resistant S. aureus and vancomycin-resistant Enterococcus were identified 3.8% and 2.3% of time, respectively. Gram-positive and negative microorganisms were frequently susceptible to cefazolin and gentamicin. Antibiogram interpretation indicates that cefazolin alone or in combination with gentamicin may be appropriate empiric antibiotic therapy in our outpatient dialysis center.

Association of a high normalized protein catabolic rate and low serum albumin level with carpal tunnel syndrome in hemodialysis patients

Carpal tunnel syndrome (CTS) is the most common mononeuropathy in patients with end-stage renal disease (ESRD). The association between chronic inflammation and CTS in hemodialysis (HD) patients has rarely been investigated. HD patients with a high normalized protein catabolic rate (nPCR) and low serum albumin level likely have adequate nutrition and inflammation. In this study, we assume that a low serum albumin level and high nPCR is associated with CTS in HD patients. We recruited 866 maintenance hemodialysis (MHD) patients and divided them into 4 groups according to their nPCR and serum albumin levels: (1) nPCR <1.2 g/kg/d and serum albumin level <4 g/dL; (2) nPCR ≥1.2 g/kg/d and serum albumin level <4 g/dL; (3) nPCR <1.2 g/kg/d and serum albumin level ≥4 g/dL; and (4) nPCR ≥1.2 g/kg/d and serum albumin level ≥4 g/dL. After adjustment for related variables, HD duration and nPCR ≥1.2 g/kg/d and serum albumin level <4 g/dL were positively correlated with CTS. By calculating the area under the receiver-operating characteristic curve, we calculated that the nPCR and HD duration cut-off points for obtaining the most favorable Youden index were 1.29 g/kg/d and 7.5 years, respectively. Advance multivariate logistic regression analysis revealed that in MHD patients, nPCR ≥1.29 g/kg/d and serum albumin <4 g/dL, and also HD duration >7.5 years were associated with CTS. A high nPCR and low serum albumin level, which likely reflect adequate nutrition and inflammation, were associated with CTS in MHD patients.

Neurological Complications of Vascular Access

Neurological problems are common in patients undergoing haemodialysis. Over 60% of patients will suffer from symptoms of underlying polyneuropathy due to uraemia or diabetes. Others will have subclinical disease demonstrable by nerve conduction studies.

Nerve injury following haemodialysis access surgery is underreported. However, sensory nerve lesions are probably common after most vascular access procedures but are rarely debilitating.

Nerve compression syndromes such as carpal tunnel and ulnar compression syndromes are common, especially in patients who have been on dialysis for some years and at least some of these are related to or exacerbated by the access. Recognition is essential as they are eminently treatable by decompression surgery. Tourniquet use appears to be safe for carpal tunnel or ulnar nerve decompression surgery.

Ischaemic monomelic neuropathy (IMN) is rare but follows a period of ischaemia during or as a result of access surgery, most commonly to construct a brachial arteriovenous fistula or graft. It is characterised by intense pain, out of proportion to any ischaemia, involves all of the upper limb nerves and may progress to involve the motor nerves eventually resulting in a useless clawed hand. It requires prompt treatment of any residual ischaemia after access creation, if necessary by access ligation, as in the established syndrome, like the even rarer complication of reflex sympathetic dystrophy, it is very difficult to offer any useful treatment other than symptomatic relief and physiotherapy.

Does carpal tunnel release provide long-term relief in patients with hemodialysis-associated carpal tunnel syndrome?

BACKGROUND

Carpal tunnel syndrome (CTS) is a common complication in patients receiving long-term hemodialysis. In the short-term however, these patients are less likely to have pain relief and restoration of function after carpal tunnel release. However, it is unclear whether patients who have release for hemodialysis-associated CTS have differing persisting relief of symptoms compared with patients with idiopathic CTS.

QUESTIONS/PURPOSES

We therefore compared (1) the severity of pain and level of function in patients who had release for hemodialysis-associated CTS with scores of patients who had release for idiopathic CTS, and (2) the operation-related complications.

METHODS

We retrospectively reviewed 36 patients with CTS who were receiving hemodialysis and 54 patients with idiopathic CTS. Control subjects were matched for age, gender, and symptom severity. We obtained Boston Carpal Tunnel Questionnaire (BCTQ) scores preoperatively and at each followup. The minimum followup was 24 months (mean, 44.3 months; range, 24-90 months), although all comparisons were made at 2 years.

RESULTS

Two years after carpal tunnel release, the mean BCTQ-symptom (S) /BCTQ-function (F) scores improved from 3.3/2.1 to 2.1/2.1 in the hemodialysis-associated CTS group and from 3.2/2.3 to 1.4/1.4 in the idiopathic CTS group. All but six patients receiving hemodialysis had lower (better) BCTQ-S scores than their initial scores. Four patients had complications, all with hemodialysis-associated CTS: two had revision carpal tunnel releases and two had delayed wound healing. We observed no arteriovenous fistula-related complication.

CONCLUSIONS

Patients with hemodialysis-associated CTS seem to remain impaired, unlike patients with idiopathic CTS, but the majority of them might have much improved CTS-related symptoms at 2 years after carpal tunnel release.

Rheumatic complications of long term treatment with hemodialysis

Patients undergoing hemodialysis therapy develop serious osteoarticular diseases. The treatment is based on prevention. The aim of our study is to determine the frequency and the associated factors to the rheumatic manifestations in hemodialysis patients. A cross-sectional study was conducted, including all hemodialysed patients in our dialysis unit. Information was obtained from patients' symptoms, examination findings, and biological and radiological signs. The frequency of symptoms was 70% in our patients. It was proportional to the duration of hemodialysis and number of hemodialysis sessions per week. Early transplantation is of course a plausible solution, but other therapies such as improved dialysis must be considered.

Thirty-Five Years of Hemodialysis: Two Case Reports as a Tribute to Nils Alwall

Two patients with long-term (35 years) survival on hemodialysis are described. Kidney replacement therapy for these patients was initiated by a pioneer in hemodialysis, Nils Alwall, in 1968 and 1971, respectively. Kidney transplantation was attempted twice in both patients; however, the dialysis-free interval was less than 18 months in both patients. These patients represent two of the longest known survivors on hemodialysis worldwide. Factors that may have influenced their survival are discussed, and the complications that have occurred over the years are presented.

Association between attributed cause of end-stage renal disease and risk of death in Brazilian patients receiving renal replacement therapy

BACKGROUND

Studies conducted in several countries have indicated that the survival of patients undergoing renal replacement therapy (RRT) depends on the attributed cause of end-stage renal disease (ESRD).

OBJECTIVES

This study was conducted to evaluate the association between attributed cause of ESRD and mortality risk in RRT patients in Brazil.

METHODS

We analyzed 88,881 patients from the Brazilian Ministry of Health Registry who were undergoing RRT between April 1997 and July 2000. Cox proportional hazards models were used to estimate the relative risk (RR) of death in patients with ESRD secondary to diabetes mellitus (DM), polycystic kidney disease (PKD), and primary glomerulopathies (GN) compared with a reference group comprised of patients with ESRD caused by hypertensive nephropathy. Patient's age, gender, and length of time (years) in RRT before inclusion in the registry (vintage) were included in the adjusted Cox model.

RESULTS

Compared with the reference group, the mortality risk was 27% lower in patients with PKD (RR=0.73, 95% CI: 0.65-0.83, p<0.0001); 29% lower in patients with GN (RR=0.71, 95% CI: 0.68-0.74, p<0.0001); and 100% greater in DM patients (RR=2.00, 95% CI: 1.92-2.10, p<0.0001). These relative risks remained statistically significant after adjustment for age, gender, and length of time in RRT before inclusion in the registry.

CONCLUSIONS

Our data indicate that compared with the patients with hypertensive nephrosclerosis as attributed cause of ESRD, patients undergoing RRT in Brazil with idiopathic glomerulopathy and polycystic kidney disease have a lower risk of mortality, and patients with diabetes mellitus have a greater risk of mortality.

Outcome of home haemodialysis patients: a case-cohort study

BACKGROUND

Randomized, controlled comparisons between home haemodialysis (HHD) and centre haemodialysis (CHD) have not been performed to date. Reported survival benefits of HHD as compared with CHD from uncontrolled studies have been attributed largely to patient selection.

METHODS

In order to minimize a selection bias, we have compared the outcome of our HHD and CHD patients with a nested case-cohort study. For each patient trained for HHD at our dialysis centre between 1970 and 1995 (n=103), a corresponding match was searched from the CHD patients by retrospective chart analysis. The pairs were matched for sex, age (+/-5 years), time of dialysis therapy onset (+/-2 years) and renal disease category. For 58 of the 103 HHD patients, a corresponding matched CHD patient was identified. Both treatment groups had the same mean age (50+/-13 years) at dialysis onset and were comparable with respect to the Khan comorbidity index, prevalence and duration of hypertension, smoking habits, history of myocardial infarction, stroke and peripheral vascular disease. In both groups, approximately 50% of the patients were transplanted during the observation period.

RESULTS

HHD patients were hospitalized less often and tended to have fewer operations as compared with CHD patients. Survival was significantly longer in HHD as compared with CHD. Five, 10 and 20 year survival rates were 93 (n=55 patients at risk), 72 (41) and 34% (11) with HHD and 64 (38), 48 (26) and 23% (4) with CHD, respectively. This survival difference persisted after adjusting for predictors of mortality, i.e. age at onset of dialysis, year of start of dialysis therapy and Khan comorbidity index.

CONCLUSIONS

HHD offers a cheap and valuable alternative to CHD, with no apparent disadvantages.

Disablement and rehabilitation in end-stage renal disease

Patients with end-stage renal disease (ESRD) are encumbered by disabilities in spite of advances in medical treatments. Research shows that exercise training is one way to improve physical work capacity and reduce functional limitations that impede role behaviors, such as shopping, personal care, homemaking, and yard maintenance. However, exercise training does not ameliorate some of the psychosocial and environmental factors that exacerbate disabilities for patients with ESRD. A disability process model described in this review illustrates that disability prevention may be more effective if exercise rehabilitation is integrated with self-management education. Research is needed to delineate which disabilities in patients with ESRD are a product of psychosocial factors and physical environments. Once identified, those disability risk factors that are amenable to change can guide the development of tailored rehabilitation interventions.

Trends in anemia management among US hemodialysis patients

This study was undertaken to describe the relationship between hematocrit (Hct) and changes in the prescribed dose of erythropoietin (EPO) as well as selected patient and process care measures across annual national samples of hemodialysis patients from 1994 to 1998. This study uses the cohorts identified in the ESRD Core Indicators Project, random samples of 6181, 6241, 6364, 6634, and 7660 patients, stratified by ESRD Networks drawn for each year from 1994 to 1998. Patient demographic and clinical information was collected from October to December for each year. Surrogates of iron stores and patterns of iron and EPO administration were profiled from 1996 to 1998. Multivariable stepwise linear regression analyses were performed to adjust for potential confounding variables and to identify independent variables associated with Hct and EPO dose. Mean Hct and EPO dose increased each year from 31.1 +/- 5.2% to 34.1 +/- 3.7% and from 58.2 +/- 41.8 U/kg to 68.2 +/- 55.0 U/kg, respectively (P = 0.0001). Increasing Hct was positively associated with male gender, more years on dialysis, older age, higher urea reduction ratio and transferrin saturation, prescription of intravenous iron, and lower ferritin and EPO dose in multivariable models (all P = 0.0001). Male gender, older age, diabetes, higher Hct, and increasing weight, urea reduction ration, and transferrin saturation were associated with lower EPO doses (all P < 0.01). Conversely, intravenous EPO and iron were associated with higher prescribed EPO doses (all P = 0.0001). Although increasing Hct is associated with decreasing EPO dose at the patient level, the increase in Hct seen across years among the cohorts of hemodialysis patients in the United States has been associated with increasing doses of EPO at the population level.

Long-term dialysis survivors: a transformational experience

In this exploratory/descriptive study, the authors examined processes involved in some kidney patients' ability to survive on dialysis. Through long semistructured interviews with 18 dialysis survivors, they identified four self-affirmations that characterized participants' restructuring of self and four sets of illness experiences that required restructuring within the context of their extant worlds. The denouement involved the participants' transformation into comprehensive, active self-managers of their disease, its treatment, and its manifestations. The authors describe the participants' affirmations and adaptations leading to transformation. Understanding this process paves the way for research into the timing and sequence entailed in transformation and lays the groundwork for the development of interventions to guide kidney failure patients to the positive outcome of transformation: comprehensive, active self-management.

Impact of years of dialysis therapy on mortality risk and the characteristics of longer term dialysis survivors

With improving survival and a decreasing probability of receiving a transplant, patients with end-stage renal disease (ESRD) are more likely to remain on hemodialysis therapy for more years than in the past. This study evaluates the effect of years on dialysis (vintage) on relative risk (RR) for death with and without adjustment for comorbidities and treatment factors. It also compares characteristics of patients on hemodialysis therapy for 7 years or longer with those on hemodialysis therapy for 1 to 7 years. Data were combined from two special US Renal Data System studies, the Case Mix Adequacy Study and Waves 1, 3, and 4 of the Dialysis Mortality and Morbidity Study. Excluding the first year of dialysis, 12,687 patients were studied during a 2-year follow-up, censoring at transplantation or loss to follow-up. Unadjusted analysis (vintage 1 to < 2 years as referent) showed that the risk for death remained nearly the same until the end of year 7 of dialysis therapy, after which the risk decreased significantly. However, with adjustment for demographics, comorbidities, and treatment factors, vintage was significantly associated with increased mortality risk during years 2 to less than 8 (RR = 1.12 to 1.30; P < 0.05). Vintage was independently associated with increased adjusted mortality among patients with and without diabetes until approximately 6 to less than 8 years of dialysis therapy. Patients on dialysis therapy for 7 years or longer were significantly (P < 0.05) more likely to be women, younger, and have lower phosphorus levels, higher hematocrits, and higher delivered dialysis doses. We conclude that adjusted mortality risk does not decrease with years on dialysis therapy, and modifiable factors deserve greater attention to improve survival among patients with ESRD with and without diabetes treated by hemodialysis.

Dementia in patients undergoing long-term dialysis: aetiology, differential diagnoses, epidemiology and management

Dementia in patients undergoing long-term dialysis has not been clearly defined; however, four different entities have been described. Uraemic encephalopathy is a complication of uraemia and responds well to dialysis. Dialysis encephalopathy syndrome, the result of acute intoxication of aluminium caused by the use of an aluminium-containing dialysate, was a common occurrence prior to 1980. However, using modern techniques of water purification, such acute intoxication can now be avoided. Dialysis-associated encephalopathy/dementia (DAE) is always associated with elevated serum aluminium levels. Pathognomonic morphological changes in the brain have been described, but the mechanism for the entry of aluminium into the CNS is incompletely understood. The mechanisms involved in the pathogenesis of the neurotoxicity associated with aluminium are numerous. Although only a very small fraction of ingested aluminium is absorbed, the continuous oral aluminium intake from aluminium-based phosphate binders, and also of dietary or environmental origin, is responsible for aluminium overload in dialysis patients. Age-related dementia, especially vascular dementia, occurs in patients undergoing long-term dialysis as frequently as it does in the general population. The differential diagnoses of dialysis-associated dementias should include investigation for metabolic encephalopathies, heavy metal or trace element intoxications, and distinct structural neurological lesions such as subdural haematoma, normal pressure hydrocephalus, stroke and, particularly, hypertensive encephalopathy and multi-infarct dementia. To prevent DAE, dietary training programmes should aim to achieve the lowest phosphate intake and pharmacological tools should be used to keep serum phosphate levels below 2 mmol/L. To prevent vascular dementia, lifestyle modification should be undertaken, including optimal physical activity and fat intake, nicotine abstinence, and targeting optimal blood glucose, cholesterol and triglyceride levels, and blood pressure, to those outlined in current recommendations.

Immunologic defects and vaccination in patients with chronic renal failure

Patients with chronic renal failure suffer from defective host defenses which are directly the result of the renal impairment, in addition to those dependent on the primary illness leading to the renal failure. The mechanisms underlying the defective responses in phagocytic cells, lymphocytes and antigen processing are likely due to either failure to adequately eliminate suppressive compounds by the defective kidneys or to improper metabolic processing of the factors by the damaged renal parynchema. That some of the defects are reversed by transplantation and not dialysis suggests that renal parenchymal metabolic activities may be involved, although it is also possible that functioning glomerular cells are capable of filtering substances that membranes are not currently capable of eliminating. The current strategy for dealing with the immunodeficiency appears to be totally based on developing means to circumvent the defective function. The other approach, correction of the impaired function, cannot be even considered until the mechanisms underlying the defective function of the cells involved in defenses are better delineated. It seems possible that one or a few compounds are pivotal in altering the function of all the affected cell lines, since, with only a small amount of effort, it is possible to relate the dysfunction to abnormal cell membrane functions in phagocytic cells, dendritic cells and lymphocytes. Until the biochemical basis of the dysfunction of all the cell types affected are better defined, such exercises cannot be translated into better management of patients with chronic renal failure. Proper function of host defenses requires that appropriate cells can properly respond to threats to host viability. For the cells of the immune system (phagocytes and lymphocytes) this means that their response to regulatory molecules be appropriate, that their mobility be normal, that their adherence to substrates be preserved, and that they can generate the appropriate response to the challenge. For neutrophils, for example, it is necessary that they recognize and mobilize appropriately to chemotactic stimuli, that they be able to adhere to and migrate through endothelial lining, that their phagocytic activity be sufficient, and that they can kill and degrade endocytosed particles and generate appropriate secretions. Similar lists of requirements for good function can be generated for any cell type in the immune defense system. Uremia, as well as currently available treatments for uremia, directly or indirectly alters the function of all phases of appropriate immune cell function. Defective host responses in uremia have been recognized for decades and there has been considerable effort in the past decade to better define the extent and mechanisms of impaired defenses. Despite the multitude of major defects in humoral, cellular, and inflammatory processes, uremic patients who are cared for today, although they remain at higher risk of serious infectious complications, can and do maintain a good quality of life, with most remaining free of major infections for years and decades.

Serum albumin: its significance in patients with ESRD

Hypoalbuminemia is a major risk factor for morbidity and mortality in the ESRD population. The Core Indicators Project notes that the serum albumin value is a measure of the patient's nutritional status. Since 1994 every outcome parameter of the Core Indicators Project has shown improvement except for the serum albumin measurement. While the serum albumin level is a measure of the visceral protein pool size, a decrease in albumin synthesis is due to more than poor nutritional intake (in part related to inadequate dialysis). Acute-phase reactants and the plasma volume status are other major factors that impact on serum albumin determination. Plasma volume expansion, albumin redistribution, exogenous loss (in peritoneal dialysis patients), and decreased albumin synthesis all contribute to hypoalbuminemia. Understanding the cause (s) of hypoalbuminemia will allow us to target treatment modalities directed at correcting the hypoalbuminemia. It is still unknown if the serum albumin can be effectively raised in the chronic dialysis patient. Also unknown is whether an increase in the serum albumin level can alter long-term morbidity and mortality. We should not be using serum albumin as an indicator of adequate dialysis or nutritional status since the causes ofhypoalbuminemia are multifactorial. It is recommended that the serum albumin level be eliminated as an indicator of nutritional status in the ESRD patient.

Parathyroid carcinoma in a dialysis patient

A 75-year-old woman who had been receiving dialysis for 3 years and had a long history of chronic renal failure attributable to reflux nephropathy was investigated for progressive hypercalcemia in the context of very high intact parathormone (iPTH) levels. Imaging showed two functional parathyroid glands in the neck. At parathyroidectomy, four variously enlarged parathyroid glands were found and completely resected, without autotransplantation. The histology of one of the glands showed invasive parathyroid carcinoma. Parathyroid carcinoma is a very rare condition, with only 16 previous cases involving dialysis patients described in the literature. We review the literature to draw together presentational and therapeutic information on the management of this problem in the setting of renal replacement therapy.

Survival of patients who have been on a waiting list for renal transplantation

INTRODUCTION

Survival of transplanted patients is generally much better than for those on dialysis. This comparison is, however, incorrect, as in order to be accepted for renal transplantation the patient has to be in a relatively good condition and in addition transplanted patients are usually younger. We compared survival of all renal replacement therapy (RRT) patients who had undergone an identical medical check-up, been accepted, and put on the waiting list for cadaveric-kidney transplantation at Huddinge University hospital. A comparison with patients who were transplanted with a kidney from a living related donor (LD) is also included.

METHODS

All patients (n=608) accepted and on the waiting list for renal transplantation between January 1987 and April 1996 formed the basis of the study. Follow-up was terminated on 31 December 1997. Survival was recorded from the date that the patients were accepted and put on the waiting list. As long as the patient was not transplanted and remained on dialysis treatment, survival was considered as 'survival on dialysis', and if transplanted, subsequent survival was defined as 'survival after cadaveric-kidney transplantation'. A patient who had been transplanted remained in that group for the rest of the observation period even if the transplantation had failed and the patient had to go back to dialysis after the surgery.

RESULTS

Five-year survival was considerably better after LD-kidney transplantation (94%), than after cadaveric-kidney transplantation (76%) or on chronic dialysis (60%). Cox hazard regression analysis gave an age-adjusted relative risk for death of 0.46 for LD-transplanted and 1.49 for remaining on dialysis compared with cadaveric-transplanted patients. Transplanted patients, however, experienced a higher mortality during the first year after the transplantation than patients still on dialysis.

CONCLUSIONS

LD-kidney transplantation is clearly associated with a superior survival. Mortality is relatively high after cadaveric-kidney transplantation, especially during the first months after surgery. Nevertheless, in the long term cadaveric kidney transplanted patients have a better survival than those remaining on dialysis.

Vintage, nutritional status, and survival in hemodialysis patients

BACKGROUND

The link between dialysis "vintage" (length of time on dialysis in months to years) and survival has been difficult to define, largely because of selection effects. End-stage renal disease (ESRD) is thought to be a wasting illness, but there are no published reports describing the associations between vintage and body composition in hemodialysis patients.

METHODS

We explored the relationships among vintage, nutritional status, and survival in a 3009 patient cohort of prevalent hemodialysis patients. Body weight, total body water, body cell mass, and phase angle by bioelectrical impedance analysis were the body composition parameters of interest. We examined vintage as an explanatory variable in multiple linear regression analyses (adjusted for age, gender, race, and diabetes) using body composition parameters and biochemical indicators of nutritional status as dependent variables. Proportional hazards regression was used to evaluate the association of vintage and survival with and without adjustment for case mix and laboratory variables.

RESULTS

Dialysis vintage was 3.8 +/- 3.7 (median 2.6) years. Body composition parameters tended to be lower after dialysis year 2. Linear estimates per year of vintage beyond year 2 include -0.66 kg body wt (P < 0.0001), -0.17 kg total body water (P = 0.0003), -0.14 kg body cell mass (P < 0.0001), and -0.07 degrees phase angle (P < 0.0001). In unadjusted analyses, vintage was not associated with survival, either as a linear or higher order term. The adjustment for case mix yielded a vintage term associated with an increased relative risk (RR) of death (RR 1.04 (95% CI, 1.01 to 1.07 per year). A further adjustment for laboratory data yielded a RR of 1.06 (95% CI, 1.03 to 1.09 per year).

CONCLUSION

Dialysis vintage is related to nutritional status in hemodialysis patients, with vintage of more than years associated with a significant decline in all measured nutritional parameters. Cross-sectional analyses probably underestimate these effects. A year accrued on dialysis is associated with a 6% increase in the risk of death, all else equal. Longitudinal assessments of nutritional status, including body composition, are required to better understand the natural history of wasting with ESRD and its implications for long-term survival.