[Guidelines for diagnosis and therapy of diabetic nephropathy]

The incidence of diabetes as cause of end-stage renal failure (ESRF) has significantly increased, and will continue to grow during the next few years. Moreover, diabetic nephropathy is associated with elevated cardiovascular morbidity and mortality. These guidelines focus on the possible intervention strategies to prevent and treat ESRF in diabetic patients. In normoalbuminuric patients, glycated haemoglobin levels less than and equal to 7.5% is mandatory for reducing the risk of incipient nephropathy. Furthermore, blood pressure levels < 130/80 mmHg are strongly recommended. In microalbuminuric patients, glycated hemoglobin levels below 7.5% and blood pressure levels below 130/80 mmHg (120/70-75 mmHg in patients < 50 years) are recommended. Moreover, there is evidence that inhibition of the rennin-angiotensin-aldosterone system, either by angiotensin-converting-enzyme inhibitors (ACE-I) or angiotensin II receptor antagonists (AIIRA) is able to reduce the incidence of overt nephropathy, regardless of blood pressure levels. Current guidelines recommed ACE-I as the first-choice drug in type 1 diabetes, while both ACE-I and AAIRA are considered first-choice therapy in type 2 diabetes. In proteinuric patients it is uncertain whether glycemic control affects the progression of nephropathy, which in turn is dramatically influenced by blood pressure. Optimal blood pressure levels are below 130/80 mmHg (120/70-75 mmHg in patients < 50 years). In type 1 diabetes there is consensus on the renoprotective role of ACE-1. In type 2 diabetes, two recent trials demonstrated that AIIRA are more effective than conventional therapy or calcium channel blockers in slowing down the progression of nephropathy. ACE-I are indeed recommended as first-choice drugs in type 1 diabetes while AIIRA are the first-choice agents for ESRF prevention in type 2 diabetes. Dialysis treatment should be started as soon as the creatinine clearance is reduced to about 10-15 mL/min. The choice of dialysis schedule should be individualized according to clinical and adequacy criteria (CAPD weekly Kt/V > or = 2 and single HD session Kt/V > or = 1.5). Simultaneous pancreas-kidney transplantation should be the first-choice therapeutic option in type 1 diabetes, while renal transplantation has been demonstrated to significantly improve the prognosis of type 2 diabetes patients with ESRF.