ANCA-associated vasculitis: a comparison of cases presenting to nephrology and rheumatology services.

BACKGROUND: Anti-neutrophil cytoplasmic antibody (ANCA) -associated vasculitis (AAV) is a disease characterized by inflammation of small vessels and detectable ANCA in the circulation. Patients may develop a broad spectrum of clinical features ranging from indolent sino-nasal disease and rashes to fulminant renal failure or acute life-threatening pulmonary haemorrhage. Consequently, patients with AAV present to a variety of specialties including nephrology and rheumatology, whose training and approaches to management of such patients may differ. There is little literature comparing patients presenting to different specialties and their outcomes. METHODS: We compared two cohorts of patients with ANCA-positive AAV presenting to either the rheumatology or nephrology department at Galway University Hospitals from June 2002 to July 2011. A standardized data collection form was used to collect information regarding baseline demographics, manifestations of AAV, initial management, relapses and complications. RESULTS: Forty-five patients were included in this study (15 rheumatology/30 nephrology). The nephrology cohort was older, had a higher C-reactive protein, Birmingham Vascular Activity Score and ANCA titer at presentation compared to the rheumatology group. Induction treatment varied between the cohorts with rheumatology patients most commonly receiving a combination of oral corticosteroids (73%) and methotrexate (60%) and nephrology patients receiving a combination of intravenous corticosteroids (93%) and cyclophosphamide (90%). Fifty-three percent of the rheumatology patients who completed induction therapy relapsed compared to 30% of the nephrology patients. CONCLUSION: This study presents two different cohorts of patients with the same disease that were managed by two different disciplines. It highlights the heterogeneity of AAV and the importance of interdisciplinary communication and cooperation when managing these patients.

Successful pregnancy after simultaneous pancreas-kidney transplantation.

The effect of pregnancy on simultaneous pancreas-kidney transplant recipients has previously been described, but experience is limited. We describe the case of a thirty-five-year-old female who previously underwent simultaneous pancreas-kidney transplant for type 1 diabetes mellitus-complicated nephropathy. An integrated multidisciplinary team including the transplant team, nephrologist, endocrinologist, and obstetrician closely followed progress during pregnancy. Blood glucose levels and HbA1c remained within normal limits, and she did not require insulin treatment at any point. She experienced deterioration in renal indices and underwent an uncomplicated, elective Caesarean section at thirty-week gestation. She delivered a male infant of 1.18 kg, appropriate for gestational age, who had hypothermia and respiratory distress, which required intubation and ventilation and an eleven-week stay in the special care baby unit. At eighteen-month followup the infant shows normal development, and there has been no deterioration in either grafts' function.

Chronic kidney disease in general practice: prevalence, diagnosis, and standards of care.

There is little prevalence data for chronic kidney disease (CKD) in Ireland and it has been suggested that rates of diagnosis of CKD in primary care are low. The aim of this cross sectional study was to examine the prevalence, diagnosis and standards of care for CKD. All patient records in three general practices in the West of Ireland were reviewed. In 2602 patients > 50 years in the community, 435 (16.7%) had chronic kidney disease defined as eGFR <60 ml/min/1.73 m2. Of these 435 individuals, only 58 (13.3%) had a diagnosis of CKD documented in their patient record. Among all patients with an eGFR <60 ml/min/1.73 m2, those with a documented diagnosis of CKD were significantly more likely to be prescribed an ACE/ARB and a lipid-lowering agent and were more likely to have had an ACR/PCR checked in the previous twelve months. Blood pressure was being appropriately monitored in the majority of patients but irrespective of eGFR level or a documented diagnosis of CKD, less than a fifth of patients had achieved a target of <130/80 mmHg. CKD is common in primary care but remains largely undiagnosed and blood pressure control remains suboptimal. A key step in improving care appears to be documenting the diagnosis which in turn appears to lead to improved standards of care and risk factor management.

What are radiologists doing to prevent contrast-induced nephropathy (CIN) compared with measures supported by current evidence? A survey of European radiologists on CIN associated with computed tomography.

BACKGROUND: Contrast-induced nephropathy (CIN) is a serious complication of the use of iodinated contrast media (CM), and is associated with increased morbidity and mortality. PURPOSE: To investigate whether radiologists take sufficient measures to prevent CIN in computed tomography (CT). MATERIAL AND METHODS: 2005 survey of 509 European radiologists who had > or =3 years' experience and performed > or =50 CT scans/week. RESULTS: The most common methods used to identify patients at risk of CIN were renal function measurements (64%), clinical judgment (55%), and patient questionnaires (31%); 9% made no routine attempt to identify at-risk patients. The most common preventive protocols used in at-risk patients included: intravenous (i.v.) saline volume repletion (59%) or oral hydration (52%) before/after CT; use of low-osmolar CM (LOCM; 40%) or isosmolar CM (IOCM; 36%); and N-acetylcysteine (20%); 8% used no hydration regimen. While 78% of respondents used < or =100 ml of CM in high-risk patients, 14% used < or =150 ml, and 9% set no volume limit. For 57% of respondents, osmolality was the most important attribute in choosing an iodinated CM in at-risk patients; 41% agreed that CIN risk is lower with IOCM versus LOCM (31% disagreed). CONCLUSION: A European radiologist survey identified a need for increased implementation of evidence-based protocols to improve CIN prevention: routine identification of at-risk patients; withdrawal of nephrotoxic drugs; use of volume repletion regimens; lowest possible volume of CM; and appropriate CM.

Association of intradialytic blood pressure changes with hospitalization and mortality rates in prevalent ESRD patients.

The relationship between blood pressure (BP) and clinical outcomes among hemodialysis patients is complex and incompletely understood. This study sought to assess the relationship between blood pressure changes with hemodialysis and clinical outcomes during a 6-month period. This study is a secondary analysis of the Crit-Line Intradialytic Monitoring Benefit Study, a randomized trial of 443 hemodialysis subjects, designed to determine whether blood volume monitoring reduced hospitalization. Logistic regression was used to estimate the association between BP changes with hemodialysis (Deltasystolic blood pressure=postdialysis-predialysis systoic BP (SBP) and the primary outcome of non-access-related hospitalization and death. Subjects whose systolic blood pressure fell with dialysis were younger, took fewer blood pressure medications, had higher serum creatinine, and higher dry weights. After controlling for baseline characteristics, lab variables, and treatment group, subjects whose SBP remained unchanged with hemodialysis (N=150, DeltaSBP -10 to 10 mm Hg) or whose SBP rose with hemodialysis (N=58, DeltaSBP > or =10 mm Hg) had a higher odds of hospitalization or death compared to subjects whose SBP fell with hemodialysis (N=230, DeltaSBP < or =-10 mm Hg) (odds ratio: 1.85, confidence interval: 1.15-2.98; and odds ratio: 2.17, confidence interval: 1.13-4.15). Subjects whose systolic blood pressure fell with hemodialysis had a significantly decreased risk of hospitalization or death at 6 months, suggesting that hemodynamic responses to dialysis are associated with short-term outcomes among a group of prevalent hemodialysis subjects. Further research should attempt to elucidate the mechanisms behind these findings.

Clinical characteristics of chronic kidney disease patients with and without diabetes: a subanalysis of the PAERI study.

AIMS: Diabetes is the leading cause of chronic kidney disease (CKD) in the United States, and cardiac disease is the primary cause of death in patients with CKD and diabetes. The Prevalence of Anemia in Early Renal Insufficiency (PAERI) study evaluated the prevalence of anemia and associated comorbidities in a community-based sample of patients with CKD. The purpose of this post hoc analysis was to identify differences, if any, in the prevalence and severity of anemia (hemoglobin < or = 12 g/dl (120 g/l)) and other clinical characteristics between CKD patients with diabetes and patients with CKD who did not have diabetes. MATERIALS AND METHODS: The PAERI study was a prospective, cross-sectional, multicenter survey. Eligible patients were > or = 18 years old with CKD, defined as serum creatinine 1.5 - 6.0 mg/dl (132.6 - 530.4 micromol/l) in females and 2.0 - 6.0 mg/dl (176.8 530.4 micromol/l) in males within 12 months before enrollment. Study duration for each patient was a single site visit. RESULTS: Of the original 5,222 patients enrolled, 3,361 had diabetes and 1,861 did not. A family history of diabetes was present in 72.7% of diabetic patients vs. 27.2% of nondiabetic patients (p < 0.0001). Patients with diabetes had a significantly higher prevalence of anemia (52.7 vs. 39.4%, p < 0.0001) and cardiac disease (55.7 vs. 42.9%, p < 0.0001). The prevalence of hypertension was high in both groups (91.5 and 89.3%). Significantly more diabetic patients than nondiabetic patients received angiotensin-converting enzyme inhibitors (60.4 vs. 43.8%, p < 0.0001). Hyperlipidemia was more common in patients with diabetes (73.9 vs. 55.4%, p < 0.0001). Patients with diabetes were slightly younger and had a significantly higher mean body mass index and lower transferrin saturation compared with nondiabetic patients. In diabetic and nondiabetic patients, more than 97% had glomerular filtration rate < 60 ml/min/1.73 m2 and more than 70% had serum creatinine < 2.5 mg/dl (221.0 micromol/l). CONCLUSIONS: These findings underscore the extent and severity of concurrent illnesses in patients with both diabetes and CKD. In those patients, diabetes was associated with a greater prevalence of serious cardiac-related comorbidities than observed in nondiabetic patients.

Associations between CMS's Clinical Performance Measures project benchmarks, profit structure, and mortality in dialysis units.

Prior studies observing greater mortality in for-profit dialysis units have not captured information about benchmarks of care. This study was undertaken to examine the association between profit status and mortality while achieving benchmarks. Utilizing data from the US Renal Data System and the Centers for Medicare & Medicaid Services' end-stage renal disease (ESRD) Clinical Performance Measures project, hemodialysis units were categorized as for-profit or not-for-profit. Associations with mortality at 1 year were estimated using Cox regression. Two thousand six hundred and eighty-five dialysis units (31,515 patients) were designated as for-profit and 1018 (15,085 patients) as not-for-profit. Patients in for-profit facilities were more likely to be older, black, female, diabetic, and have higher urea reduction ratio (URR), hematocrit, serum albumin, and transferrin saturation. Patients (19.4 and 18.6%) in for-profit and not-for-profit units died, respectively. In unadjusted analyses, profit status was not associated with mortality (hazard ratio (HR)=1.04, P=0.09). When added to models with profit status, the following resulted in a significant association between profit status (for-profit vs not-for-profit) and increasing mortality risk: URR, hematocrit, albumin, and ESRD Network. In adjusted models, patients in for-profit facilities had a greater death risk (HR 1.09, P=0.004). More patients in for-profit units met clinical benchmarks. Survival among patients in for-profit units was similar to not-for-profit units. This suggests that in the contemporary era, interventions in for-profit dialysis units have not impaired their ability to deliver performance benchmarks and do not affect survival.

Explaining counter-intuitive clinical outcomes predicted by Kt/V.

Population-based studies of maintenance hemodialysis patients have demonstrated a reproducible relationship between the dose of hemodialysis and mortality and morbidity outcomes. In these analyses, which have aggregated hemodialysis patient subgroups, improved outcomes are associated with greater doses of hemodialysis. However, remarkable counterintuitive findings are observed if patients are analyzed by subgroups based on their race, gender, and anthropometric and blood-based biomarkers of nutritional state. For example, blacks generally receive lower doses of hemodialysis than whites, but enjoy relatively improved survival; patients who receive the highest doses of hemodialysis have an increased death risk; and the dose response curve between hemodialysis and survival is altered based on the patients' body mass index. These seemingly paradoxical relationships between hemodialysis dose and patient survival can be explained because of the use of mathematical urea kinetic constructs as clinical outcome predictors; they integrate a measure of solute removal (K x t) with an anthropometric surrogate of nutrition, the urea distribution volume (V). Both these measures have an independent influence on patient survival and in some clinical circumstances are of unequal power as clinical outcome predictors. These complex interactions must be kept in perspective as clinical care is delivered in the context of hemodialysis dose.

Long-term outcomes of revascularization for peripheral vascular disease in end-stage renal disease patients.

The occurrence of peripheral vascular disease (PVD) and atraumatic lower-extremity amputations is significantly greater in patients with end-stage renal disease (ESRD) than those with normal renal function. Moreover, the mortality for dialysis patients undergoing atraumatic lower-extremity amputations is far greater. Because PVD requiring amputation is an extreme form of PVD, we tested the hypothesis that mortality and intermediate outcomes for patients with ESRD undergoing lower-extremity revascularization, a less extreme form of PVD, would be equivalent to that for patients without ESRD. This is a retrospective case-control analysis of lower-extremity revascularization in patients with ESRD. Procedures in patients with ESRD were matched with procedures in non-ESRD controls for patient age, sex, race, diabetes mellitus, and hospital setting. Patient survival, graft survival, and limb salvage rates were determined using Kaplan-Meier analysis. Subjective interpretation of functional and symptomatic improvement was determined by telephone interviews with patients or relatives. Thirty-one procedures were performed on 20 patients with ESRD and 64 matched procedures were performed on 57 patients without ESRD. In the ESRD group, median patient survival was 1.72 years compared with 5.17 years for the control group (P < 0.001). Time to 50% limb loss was 1.24 years in the ESRD group and longer than 5.65 years in the control group (P < 0.001). Time to 50% graft patency loss was 0.70 years in the ESRD group and longer than 5.5 years in the control group (P < 0.05). Subjective improvement was less in patients with ESRD. Outcomes of lower-extremity revascularization in patients with ESRD are inferior to those in non-ESRD controls. The mortality rate for patients with ESRD who undergo revascularization is extremely high. Patient-related variables (eg, increased prevalence of hypertension and cardiovascular disease) and/or provider-specific factors (eg, timing of surgery in the course of PVD) may be responsible for poorer outcomes.

Differential survival after coronary revascularization procedures among patients with renal insufficiency.

BACKGROUND: Acute myocardial infarction, cardiac arrest, and other cardiac events are the major cause of mortality among patients with renal insufficiency. Previous studies of interventions for coronary artery disease among patients with renal insufficiency have not controlled for potentially confounding factors such as coronary artery disease severity and left ventricular function. This study investigates the comparative survival for patients with renal insufficiency and coronary artery disease following coronary artery bypass graft (CABG) surgery as compared with percutaneous coronary artery intervention (PCI), while controlling for confounding factors. METHODS: This retrospective cohort study of patients undergoing CABG surgery or PCI discharged between 1993 and 1995 uses the New York Department of Health databases and Cox proportional hazards analyses to estimate the mortality risk associated with CABG as compared with PCI for patients with renal insufficiency. Renal function was categorized as creatinine <2.5 mg/dL (N = 58,329), creatinine > or =2.5 mg/dL (N = 840), and end-stage renal disease (ESRD) requiring dialysis (N = 407). RESULTS: Patients with either ESRD or serum creatinine > or =2.5 mg/dL had more severe coronary artery disease and a greater frequency of comorbid conditions as compared with patients with creatinine <2.5 mg/dL. Creatinine > or =2.5 mg/dL and ESRD were both associated with an increased mortality risk among all distributions of coronary artery disease anatomy. Among patients with ESRD, the risk ratio (RR) of mortality for patients undergoing CABG compared with PCI was 0.39 (95% CI, 0.22 to 0.67, P = 0.0006). Among patients with creatinine > or =2.5 mg/dL, CABG surgery did not convey a survival benefit over PCI (RR, 0.86, 95% CI, 0.56 to 1.33, P = 0.50). CONCLUSIONS: This study demonstrates a survival benefit among patients with ESRD undergoing CABG surgery as compared with PCI, while controlling for severity of coronary artery disease, left ventricular dysfunction, and other comorbid conditions. These results suggest that management decisions among patients with coronary artery disease should be made in the context of not only location and severity of coronary artery lesions, but also on the presence and severity of renal dysfunction.

Management of small renal tumors: an overview.

The incidental finding of a small renal mass poses a therapeutic dilemma. The traditional treatment of clinically important masses has been radical nephrectomy. Recently, nephron-sparing surgery has emerged as a viable alternative; and experimental minimally invasive percutaneous tissue ablation techniques, including cryotherapy and radiofrequency ablation, are being evaluated. In this review, we discuss the dilemma posed by frequent renal imaging and the increased proportion of incidental tumors being detected, the limitations of needle biopsies for histologic diagnosis, nephron-conserving and minimally invasive surgery, and the possible merits of radiofrequency ablation and cryotherapy. We envision a defined role for minimally invasive percutaneous or extracorporeal ablation of small renal tumors.

Pathogenesis of beta(2)-microglobulin amyloidosis: role of monocytes/macrophages.

beta(2)-microglobulin (beta(2)M) amyloidosis (A beta(2)M) is a serious, often incapacitating complication for patients undergoing long-term hemodialysis. Amyloid deposits composed of beta(2)M fibrils as the major constituent protein are mainly localized in joints and periarticular bone and lead to chronic arthralgias, carpal tunnel syndrome, and eventually destructive arthropathy. Although recent histologic studies have shown the accumulation of monocytes/macrophages around amyloid deposits, the factor(s) causing their infiltration and pathologic involvement have yet to be fully elucidated. Immunohistochemical staining reveals that macrophages in tenosynovial tissues express CD13, CD14, CD33, HLA-DR, and CD68 antigens on their surfaces and express interleukin (IL)-1 beta, tumor necrosis factor (TNF)-alpha, and IL-6. Many of these cells also express LFA-1 (CD11a/CD18), Mac-1 (CD11b/CD18), and VLA-4 (CD49d/CD29) on their surfaces. AGE-modified beta(2)M enhances chemotaxis of monocytes and stimulates macrophages to release bone-resorbing cytokines, such as IL-1 beta, TNF-alpha and IL-6. Via a RAGE-mediated pathway, AGE-modified, but not unmodified beta(2)M, significantly delays constitutive apoptosis of human peripheral blood monocytes. Monocytes survival in an advanced glycation end product (AGE) beta(2)M-containing microenvironment is associated with their phenotypic alteration into macrophage-like cells that generate more reactive oxygen species and elaborate greater quantities of IL-1 beta and TNF-alpha. Thus through regulation of their survival and differentiation, AGE beta(2)M in amyloid deposits may be able to influence the presence and quantity of infiltrated monocytes, and hence their biologic effects.

Racial inequity in America's ESRD program.

The end-stage renal disease (ESRD) program has a significant overrepresentation of racial and ethnic minority groups. The increased susceptibility of nonwhite populations to ESRD has not been fully explained and probably represents a complex interplay of genetic, cultural, and environmental influences. Because the program delivers care under a uniform health care payment system, it represents a unique environment in which to explore variation in health care delivery. A number of disparities in outcomes and delivery of ESRD care have been noted for racial minority participants. These include possible overdiagnosis of hypertensive nephrosclerosis, decreased provision of renal replacement therapy, limited referral for home dialysis modalities, underprescription of dialysis, increased use of synthetic grafts rather than fistulas as permanent angioaccess, and delayed wait-listing for renal transplantation. Transplantation inequities mean that black patients are likely to remain on dialysis relatively longer, so that their susceptibility to less than optimal processes of care increases disproportionately. Improved survival and quality of life (QOL) for blacks with ESRD may have encouraged provider complacency about racial disparities in the ESRD program and in particular about referral for transplantation. It is also apparent that minority ESRD patients may, similar to their non-ESRD counterparts, be referred less frequently for invasive cardiovascular (CV) procedures. Despite these observations of inequality in ESRD care, the adjusted mortality for minority participants in the ESRD program are better than for the majority population. This seeming paradox may define an opportunity to improve outcomes for minorities with ESRD even more.

The association of epsilon-aminocaproic acid with postoperative decrease in creatinine clearance in 1502 coronary bypass patients.

UNLABELLED: Renal dysfunction is a common serious complication after cardiac surgery. Reports of proteinuria and hyperkalemia after cardiac surgery with epsilon-aminocaproic acid (EACA) have therefore raised concerns for renal safety. Since EACA renders these markers unreliable, we used perioperative change in creatinine clearance (DCrCl) to test the hypothesis that EACA is associated with greater reductions in creatinine clearance after heart surgery, particularly for patients with renal disease. We evaluated data from all elective primary coronary bypass patients during EACA introduction at our institution (July 1, 1991-December 31, 1992; 10 g iv bolus pre-cardiopulmonary bypass, then 1 g/h for 5 h). DCrCl was calculated using preoperative (CrPre) and postoperative peak serum creatinine values, using the Cockroft-Gault equation. Patients with CrPre > or = 133 micromol/L were also separately analyzed. Evaluated patients (n = 1502, +/-EACA; 581/905, 16 exclusions) included 233 with CrPre > or = 133 micromol/L (+/-EACA; 98/135). Multivariate analyses confirmed several known risk factors, but no association between DCrCl and EACA in all patients (P: = 0.66), and the subgroup with CrPre > or = 133 micromol/L (P: = 0.42). IMPLICATIONS: In a large population of primary Coronary Artery Bypass Graft including a subset with preoperative renal dysfunction, there were no postoperative reductions in creatinine clearance attributable to epsilon-aminocaproic (EACA) administration. This retrospective study suggests that moderate epsilon-aminocaproic acid dosing during cardiac surgery is safe for the kidney; however, this inference is based on a single marker of renal dysfunction and requires prospective confirmation using a variety of tests of renal function.