Manuel Burdese

Impact of contrast-induced acute kidney injury definition on clinical outcomes

BACKGROUND Contrast-induced acute kidney injury (CIAKI) is a frequent complication after infusion of contrast media in patients undergoing percutaneous coronary intervention. A wide range of CIAKI rates occurs after intervention between 3% and 30%, depending on the definition. The aim of this study was to identify which methodology was more effective at recognizing patients at high risk for in-hospital and out-of-hospital adverse events. METHODS AND RESULTS Serum creatinine increases, after contrast agent infusion, were evaluated in 755 consecutive and unselected patients. Incidences of CIAKI diagnosed by 2 common definitions varied from 6.9% (creatinine increase of ≥0.5 mg/dL, CIAKI-0.5) to 15.9% (creatinine increase of ≥25%, CIAKI-25%). Significant differences appeared between the 2 definitions of sensitivity to predict renal failure according to receiver operating characteristic curve analysis (98% for CIAKI-0.5 and 62% for CIAKI-25%), using a cutoff value of postprocedural glomerular filtration rate of 60 mL/min. Both definitions of CIAKI were related to composite adverse events, but CIAKI-0.5 showed a stronger predicting value (odds ratio 2.875 vs 1.802, P = .036). In multivariate linear regression, only CIAKI-0.5 was a predictive variable of death (odds ratio 3.174, 95% CI 1.368-7.361). CONCLUSIONS An increase in serum creatinine of ≥0.5 mg/dL is more sensitive because it recognizes more selectively those patients with a higher risk of mortality and morbidity. Serum creatinine increases of ≥25% overestimate CIAKI by including many patients without postprocedural relevant deterioration of renal function and affected by a lower risk of adverse events at follow-up.

Low-protein vegetarian diet with alpha-chetoanalogues prior to pre-emptive pancreas-kidney transplantation.

BACKGROUND Pre-emptive pancreas-kidney transplantation is increasingly considered the best therapy for irreversible chronic kidney disease (CKD) in type 1 diabetics. However, the best approach in the wait for transplantation has not yet been defined. AIM To evaluate our experience with a low-protein (0.6 g/kg/day) vegetarian diet supplemented with alpha-chetoanalogues in type 1 diabetic patients in the wait for pancreas-kidney transplantation. METHODS Prospective study. Information on the progression of renal disease, compliance, metabolic control, reasons for choice and for drop-out were recorded prospectively; the data for the subset of patients who underwent the diet while awaiting a pancreas-kidney graft are analysed in this report. RESULTS From November 1998 to April 2004, 9 type 1 diabetic patients, wait-listed or performing tests for wait-listing for pancreas-kidney transplantation, started the diet. All of them were followed by nephrologists and diabetologists, in the context of integrated care. There were 4 males and 5 females; median age 38 years (range 27.9-45.5); median diabetes duration 23.8 years (range 16.6-33.1), 8/9 with widespread organ damage; median creatinine at the start of the diet: 3.2 mg/dl (1.2-7.2); 4 patients followed the diet to transplantation, 2 are presently on the diet, 2 dropped out and started dialysis after a few months, 1 started dialysis (rescue treatment). The nutritional status remained stable, glycemia control improved in 4 patients in the short term and in 2 in the long term, no hyperkalemia, acidosis or other relevant side effect was recorded. Proteinuria decreased in 5 cases, in 3 from the nephrotic range. Albumin levels remained stable; the progression rate was a loss of 0.47 ml/min of creatinine clearance per month (ranging from an increase of 0.06 to a decrease of 2.4 ml/min) during the diet period (estimated by the Cockroft-Gault formula). CONCLUSIONS Low-protein supplemented vegetarian diets may be a useful tool to slow CKD progression whilst awaiting pancreas-kidney transplantation.

Cholesterol crystal embolism syndrome in dialysis patients: an emerging clinical diagnosis?

Background: Cholesterol crystal embolism syndrome (CCE) is an increasing end-stage renal disease cause. Few cases have been described on dialysis, despite the high prevalence of the predisposing factors. Methods: The diagnostic criteria of the present study were: skin lesions, myalgia, fatigue, fever and acute inflammatory serologic signs, in the presence of severe vasculopathy. The precipitating factors were: anticoagulation, endovascular intervention and ulcerated atherosclerotic plaque. Results: Between October 2003 and September 2005, CCE was diagnosed in 6 dialysis patients (of 200–210 on chronic treatment): 5 males, 1 female, median age 59.5 years (47–70) and end-stage renal disease follow-up 11.5 years (3–25). All had severe vasculopathy, 5 cardiopathy, and 4 were failed graft recipients. The treatment included: peritoneal dialysis, daily dialysis, ‘conventional’ hemodialysis (2 cases) and hemodiafiltration. The diagnosis was based on the clinical-laboratory picture in 1 patient. In the 5 others clues were present (dicumarol therapy, angioplasty, femoral artery thrombosis, CCE predialysis and ulcerated aortic plaque). The therapeutic approach consisted of corticosteroids (5 cases), statins (4 cases) and prostaglandin analogues (4 cases). Conclusion: The differential diagnosis of CCE should also be considered in dialysis patients (necrotic lesions, limb pain and vasculitis-like signs).

Mitochondrial neurogastrointestinal encephalomyopathy treated with peritoneal dialysis and bone marrow transplantation

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE) is a rare disease caused by thymidine phosphorylase deficiency which leads to toxic accumulations of thymidine (dThd) and deoxyuridine (dUrd). It lacks an established treatment and the prognosis is traditionally poor. We report a case of a young female patient with normal renal function and MNGIE treated by peritoneal dialysis (PD) and allogeneic bone marrow transplantation (BMT). PD was effective in reducing dThd and dUrd plasma levels and in improving clinical symptoms. To our knowledge, this is the first report on the beneficial effects of PD regarding MNGIE neurological symptoms. PD, therefore, should be considered especially in medically compromised patients as a supportive treatment to improve clinical conditions before BMT.

The grafted kidney takes over: disappearance of the nephrotic syndrome after preemptive pancreas-kidney and kidney transplantation in diabetic nephropathy

This report describes the rapid and complete reversal of proteinuria after preemptive transplantation in diabetic nephropathy. Case 1 was a 42-year-old woman with type 1 diabetes (before pancreas-kidney graft: serum creatinine 1.6 mg/dL and proteinuria 9.1 g/day; 1 month after pancreas-kidney graft: proteinuria 0.3 g/day and creatinine 1.3 mg/dL). Case 2 was a 48-year-old man with type 2 diabetes (before kidney graft: creatinine 2 mg/dL and proteinuria 5.9 g/day; 1 month after: proteinuria 0.7 g/day and creatinine 1.1 mg/dL). The proteinuria pattern changed (pre: glomerular nonselective, tubular complete; post: physiologic). Renal scintiscan (99mTC-MAG3) demonstrated functional exclusion of the native kidneys, despite high pretransplant clearance (> 50 mL/min). The effect was not linked to euglycemia or readily explainable by pharmacologic effects (no difference in renal parameters after pancreas transplantation with the same protocols). These data confirm the efficacy of preemptive kidney and kidney-pancreas transplantation in diabetic nephrotic syndrome and indicate that a regulatory hemodynamic effect should be investigated.

CKD patients and erythropoietin: do we need evidence-based informed consent?

Background Consent to therapy is increasingly requested in the form of “informed consent”. Objective To validate an evidence-based informed consent form for erythropoietin (EPO) therapy and to evaluate patient opinions about the informed consent approach. Methods An evidence-based informed consent form was developed as part of the Evidence-Based-Medicine course at the Medical School of Turin, Italy. It was validated by anonymous questionnaires (0–10 analogical scales and open answers) administered to patients at different stages of CKD (19 pre-ESRD, 26 hemodialysis, 12 transplant patients) attending an outpatient unit of the University of Turin, to 8 nurses, and to 26 medical students. Results All individuals filled in the questionnaire. Interest in a detailed explanation of the therapy was high (median 9), as was comprehension (median 9), with no differences between patients with regard to disease stage (pre-ESRD vs. RRT) or educational level. Prior knowledge of the therapy was affected by the educational level (p=0.013 for the advantages and p=0.004 for the side effects) and the professional role (patients vs caregivers: p=0.009 for the advantages and p<0.001 for side affects); patient knowledge of the advantages (median 6) tended to increase as the disease progressed (p=0.015). The most common response by patients was that informed consent was necessary for all drugs (35.1%); 73.1% of the caregivers considered it necessary only for severe side effects. The preferred modality of consent was discussion with the caregiver during the clinical controls (42% of all cases). Conclusions Patient interest in and comprehension of an informed consent form with a detailed explanation of the therapy was high; the caregivers opinion was still the most valued teaching tool.