[Erythropoiesis-stimulating agents in chronic kidney disease: which route of administration?]. / Agenti stimolanti l'eritropoiesi nell'insufficienza renale cronica: quale via di somministrazione?

In the last twenty years, erythropoiesis-stimulating agents (ESAs) have improved the management of renal anemia, with significant amelioration of quality of life in patients on hemodialysis. ESAs can be administered both intravenously and subcutaneously. In predialysis chronic kidney disease and in peritoneal dialysis, the administration route is necessarily subcutaneous. In hemodialysis the intravenous route was initially preferred because of the presence of ready vascular access for drug administration. Subsequent studies have demonstrated that the subcutaneous route allowed the achievement of optimal levels of hemoglobin with a reduction of mean administered dose, number of injections, and costs. A few years ago, the finding of a higher risk of pure red cell aplasia associated with subcutaneous administration of epoetin reopened the debate about the route of administration. We here review the studies on the preferable route of administration of epoetin and darbepoetin- alpha, in terms of efficacy and safety, and take a look at future perspectives.

[Diagnostic role of ambulatory blood pressure monitoring in non-dialysis CKD patients]. / Monitoraggio della pressione arteriosa per 24 ore: indicazioni e utilità nella IRC pre-dialitica.

In chronic kidney disease, blood pressure control is a major aim of therapy to slow down renal disease progression and reduce the cardiovascular risk. Ambulatory blood pressure monitoring is a valid tool to define the prognosis and indicated therapy for hypertension. It allows to detect blood pressure patterns such as the white-coat effect, resulting in a better definition of the cardiovascular risk profile. Description of the circadian pressure rhythm, moreover, may reveal the presence of physiological nocturnal loss (dipping status). Recently, it has been demonstrated that a non-dipping status is associated with a higher risk of end-stage renal disease and more rapid progression of kidney disease independent of blood pressure control. Furthermore, longitudinal studies have demonstrated that a non-dipping status is associated with increased cardiovascular morbidity and mortality in the general population and in hypertensive patients. We have less information on this issue in chronic kidney disease. In this high-risk subgroup of hypertensive patients, it remains ill-defined whether ambulatory blood pressure monitoring predicts cardiovascular outcomes better than in-office measurement.

[Hypertension in patients on hemodialysis: the role of salt intake]. / L'ipertensione arteriosa nell'uremico in emodialisi: importanza dell'intake di sale.

In the 1960s, about 10% of hemodialysis (HD) patients had hypertension; the current percentage of hypertensive patients has risen to 70-75%. The scarce implementation of low-salt diets and the increment of dialysate sodium concentration aimed at ameliorating treatment tolerability are the main causes of the currently poor hypertension control. Considerable sodium intake activates a vicious circle: an increase in serum osmolarity, greater thirst and greater water intake, high inter-dialytic weight gains, need for large ultrafiltration rates, more frequent episodes of intradialytic hypotension, failure to achieve dry weight, progressive extra-cellular volume (ECV) expansion, and finally, blood pressure (BP) increase. Therefore, many studies have pointed out the importance of a low-salt diet in HD; it has been proven that the normalization of BP and ECV overload with a low-salt diet is associated with left ventricular hypertrophy regression and diastolic dysfunction improvement. Preparing meals with fresh foods, using spices, avoiding salt when cooking, and drastically limiting salty foods reduce dietary sodium down to about 6 g/day. Sodium intake during inter-dialytic periods can easily be assessed by measuring the changes in serum sodium concentration and in body weight.

[Clinical management of the patient affected with acute renal failure (ARF) secondary to volume depletion]. / Gestione clinica del paziente con insufficienza renale acuta (IRA)da ipovolemia.

Most cases of ARF are secondary to volume depletion. In the literature, very few scientific publications address the problem of what to do when confronted with such a patient. As regarding the diagnosis of hypovolemia, an accurate history and physical examination can help to determine both the presence and etiology of volume depletion; postural hypotension (decrement in systolic blood pressure of more than 20 mmHg after standing from the supine position), associated with a pulse increment of 30 beats/min or more and dizziness are specific symptoms of hypovolemia. Laboratory indices are useful to diagnose volume depletion, but their interpretation is not simple, and they may not be available in the non-nephrologic environment. Fluid replacement therapy in hypovolemia is largely dependent upon the type of fluid that has been lost and concurrent electrolytic and acid-base disorders. Patients with hypernatremia and volume depletion should receive mild hypotonic solutions, whereas those with hyponatremia and hypovolemia should receive mild hypertonic solutions. The entity of reinfusion depends on daily losses. Conversely, monitoring of body weight can be considered an adequate index of fluid balance. Concerning the treatment of ARF, the use of loop diuretics in the early phases of pre-renal ARF decrease oxygen consumption in the tubular cells by inhibiting transcellular sodium transport, therefore preventing or limiting ischemic cell injury. The use of loop diuretics should also be evaluated in intermediate syndrome and ischemic NTA where diuretics can, respectively, reduce renal ischemia and convert oliguric ARF into the non-oliguric form.