Clinical and ultrasound evaluation for hemodialysis access creation.

Chronic kidney disease (CKD) is an emerging global burden with an increasing number of patient's requiring renal replacement therapy (RRT), with hemodialysis being the most prevalent dialysis modality. A functioning vascular access remains the main constrain for an adequate treatment. Clinical and, in some patients, ultrasound evaluation are fundamental for better access planning. Access planning is dependent not only on patient clinical characteristics and preference but also in vascular patrimony. As such, ultrasound evaluation aids in characterizing patient arterial and venous upper arm anatomy and provides information for which access would better suit each patient. Doctors dealing with CKD patients should be familiar with the role of ultrasound and Doppler use in access planning.

Post-mortem liver and bone marrow iron quantification in haemodialysis patients: A prospective cohort study.

BACKGROUND: Magnetic resonance liver scans indicate that iron overload is common in haemodialysis (HD) patients. However, histological evidence is scarce. METHODS: Liver biopsy and bone marrow aspirate were obtained in the first 24h post mortem from 21 adult HD patients. Biochemical liver iron content (LIC) was quantified by electrothermal atomization atomic absorption spectrophotometry. Tissue iron deposition was graded in the liver and bone marrow using Scheuer and Gale's criteria, respectively. FINDINGS: Median LIC was 42.5 (22.9-69.7) µmol/g and the majority (n=11; 57%) had mild to moderate liver iron overload (LIC >36 µmol/g). Scheuer grade was 2 (1-3) and 13 (62%) of liver biopsies had increased (> 1) iron deposition. In the bone marrow, median Gale's grade was 3 (3-4) and 9 (45%) patients had increased (>3) iron content. Contrary to old autopsy studies, done in the pre-erythropoiesis-stimulating agents (ESAs) era, both liver and bone marrow were iron replete and showed a positive correlation (r=0.71, p<0.001). Ferritin proved to have a good diagnostic accuracy for liver iron overload (0.87 95% CI 0.71-1.00) with an optimal cut-off value of 422 ng/ml. Haemoglobin was negatively associated with both LIC (r= -0.46, p=0.04) and iron content in the bone marrow (p=0.04). Patients with increased LIC had higher resistance to ESAs (p=0.02), yet no association with previous IV iron therapy. INTERPRETATION: In the majority of HD patients there was iron accumulation in both the liver and bone marrow that associated with anaemia severity and resistance to ESAs, suggesting a blocking mechanism of iron's utilization. FUNDING: None.

Clinical and ultrasound evaluation for hemodialysis access creation / Evaluación clínica y ecográfica para la creación de acceso para hemodiálisis

Chronic kidney disease (CKD) is an emerging global burden with an increasing number of patient's requiring renal replacement therapy (RRT), with hemodialysis being the most prevalent dialysis modality. A functioning vascular access remains the main constrain for an adequate treatment. Clinical and, in some patients, ultrasound evaluation are fundamental for better access planning. Access planning is dependent not only on patient clinical characteristics and preference but also in vascular patrimony. As such, ultrasound evaluation aids in characterizing patient arterial and venous upper arm anatomy and provides information for which access would better suit each patient. Doctors dealing with CKD patients should be familiar with the role of ultrasound and Doppler use in access planning. (AU)

La enfermedad renal crónica (ERC) es una carga global emergente con un número creciente de pacientes que precisan tratamiento renal sustitutivo (TRS) y la hemodiálisis es la modalidad de diálisis más prevalente. Un acceso vascular funcional sigue siendo la principal limitación para un tratamiento adecuado. La evaluación clínica y, en algunos pacientes la ecográfica, son fundamentales para una mejor planificación del acceso. La planificación del acceso depende no solo de las características clínicas y las preferencias del paciente, sino también de la anatomía vascular. Por tanto, la evaluación ecográfica ayuda a caracterizar la anatomía arterial y venosa de la parte superior del brazo del paciente y ofrece información sobre qué acceso sería más adecuado para cada paciente. Los médicos que tratan a pacientes con ERC deben estar familiarizados con el papel de la ecografía y el uso del Doppler en la planificación del acceso. (AU)

Intravenous iron in heart failure and chronic kidney disease / El hierro intravenoso en la insuficiencia cardiaca y la enfermedad renal crónica

Intravenous iron therapy is increasingly being used worldwide to treat anemia in chronic kidney disease and more recently iron deficiency in heart failure. Promising results were obtained in randomized clinical trials in the latter, showing symptomatic and functional capacity improvement with intravenous iron therapy. Meanwhile, confirmation of clinical benefit in hard-endpoints such as mortality and hospitalization is expected in large clinical trials that are already taking place. In chronic kidney disease, concern about iron overload is being substituted by claims of direct cardiovascular benefit of iron supplementation, as suggested by preliminary studies in heart failure.We discuss the pitfalls of present studies and gaps in knowledge, stressing the known differences between iron metabolism in heart and renal failure. Systemic and cellular iron handling and the role of hepcidin are reviewed, as well as the role of iron in atherosclerosis, especially in view of its relevance to patients undergoing dialysis. We summarize the evidence available concerning iron overload, availability and toxicity in CKD, that should be taken into account before embracing aggressive intravenous iron supplementation. (AU)

La suplementación con hierro intravenoso es cada vez más frecuente a nivel mundial en el tratamiento de la enfermedad renal crónica (ERC) y, más recientemente, se ha utilizado para tratar el déficit de hierro en la insuficiencia cardiaca (IC). En esta última, se obtuvieron resultados alentadores en estudios clínicos randomizados, demostrando una mejoría sintomática y en la capacidad funcional de la IC. Sin embargo, aún se aguarda la confirmación de beneficio clínico en los objetivos principales como mortalidad y hospitalización en los estudios clínicos amplios que actualmente están en curso.En la presente revisión se discuten las dudas que se presentan en los estudios actuales y las lagunas en el conocimiento en relación con las diferencias entre la ERC y la IC sobre el metabolismo del hierro. Se ofrece una revisión sobre el manejo celular y sistémico del hierro, así como sobre el papel de la hepcidina. Adicionalmente, se explica el papel del hierro en la ateroesclerosis y su importancia principalmente en los pacientes en diálisis. Por otra parte, en esta revisión se incluye un resumen actualizado sobre lo que existe de evidencia en relación con la sobrecarga de hierro, su disponibilidad y toxicidad en la ERC, lo cual se debe tener en cuenta antes de decidir realizar una terapia intravenosa agresiva con hierro. (AU)

Clinical and ultrasound evaluation for hemodialysis access creation.

Chronic kidney disease (CKD) is an emerging global burden with an increasing number of patient's requiring renal replacement therapy (RRT), with hemodialysis being the most prevalent dialysis modality. A functioning vascular access remains the main constrain for an adequate treatment. Clinical and, in some patients, ultrasound evaluation are fundamental for better access planning. Access planning is dependent not only on patient clinical characteristics and preference but also in vascular patrimony. As such, ultrasound evaluation aids in characterizing patient arterial and venous upper arm anatomy and provides information for which access would better suit each patient. Doctors dealing with CKD patients should be familiar with the role of ultrasound and Doppler use in access planning.

Intravenous iron in heart failure and chronic kidney disease.

Intravenous iron therapy is increasingly being used worldwide to treat anemia in chronic kidney disease and more recently iron deficiency in heart failure. Promising results were obtained in randomized clinical trials in the latter, showing symptomatic and functional capacity improvement with intravenous iron therapy. Meanwhile, confirmation of clinical benefit in hard-endpoints such as mortality and hospitalization is expected in large clinical trials that are already taking place. In chronic kidney disease, concern about iron overload is being substituted by claims of direct cardiovascular benefit of iron supplementation, as suggested by preliminary studies in heart failure. We discuss the pitfalls of present studies and gaps in knowledge, stressing the known differences between iron metabolism in heart and renal failure. Systemic and cellular iron handling and the role of hepcidin are reviewed, as well as the role of iron in atherosclerosis, especially in view of its relevance to patients undergoing dialysis. We summarize the evidence available concerning iron overload, availability and toxicity in CKD, that should be taken into account before embracing aggressive intravenous iron supplementation.

Amanita poisonings resulting in acute, reversible renal failure: new cases, new toxic Amanita mushrooms.

BACKGROUND: Renal failure as a consequence of eating mushrooms has been reported repeatedly after ingestion of webcaps of the Cortinarius orellanus group. But mushrooms of the genus Amanita can also cause renal failure: Amanita smithiana (North America) and Amanita proxima (Mediterranean area). Here, we discuss poisonings caused by other white amanitas. A German and--independently--two Portuguese patients reported the ingestion of completely white mushrooms with ring. Similar to intoxications with A. smithiana or A. proxima, the clinical picture was characterized by nausea and vomiting 10-12 h after ingestion, severe acute renal failure and mild hepatitis. Renal biopsy showed acute interstitial nephritis and tubular necrosis. Two patients were given temporary haemodialysis. All have fully recovered their renal function. Poisonings caused by mushrooms containing the toxin of A. smithiana were suspected. We tested 20 Amanita species for the presence of this toxin. METHODS: Thin layer chromatography was applied to detect A. smithiana nephrotoxin in herbarium specimens using authentic material of A. smithiana as reference. RESULTS: A. smithiana toxin could be detected in Amanita boudieri, Amanita gracilior and in Amanita echinocephala. A. boudieri was collected by the Portuguese patients. A. echinocephala is the only nephrotoxic Amanita growing North of the Alps and is suspected to be the cause of renal failure in the German patient. No A. smithiana toxin was detectable in the nephrotoxic A. proxima. CONCLUSIONS: A. boudieri, A. gracilior and A. echinocephala are nephrotoxic. These intoxications are clinically similar to that of A. smithiana, with acute reversible renal failure and mild hepatitis but are different in their clinical picture from Orellanus syndrome characterized by a delayed onset of severe and often irreversible renal failure.

Haemolytic uraemic syndrome associated with H1N1 influenza.

Haemolytic uraemic syndrome (HUS) is one of the two forms of thrombotic microangiopathies and is characterized by the triad of microangiopathic haemolytic anaemia, thrombocytopaenia, and acute renal failure. It has been associated with bacterial and viral infections as well as non-infective causes. We report a subject who presented with HUS associated with an influenza-like syndrome which was confirmed as an influenza A (H1N1) infection. There are reports of HUS associated with seasonal influenza, but there have been no reported cases of HUS after novel influenza A (H1N1) in the literature so far.