Symptoms and manifestations
As repeatedly expressed in the article, diabetic nephropathy is a progressive disease, which through stages of increasing gravity passes from the most total asymptomatic to chronic irreversible renal failure.
STADIUM I
Defined as a stage of glomerular hyperfiltration, it is characterized by the absence of symptoms and apparently normal renal function. In reality, histological alterations can also be detected at this stage and it is possible to demonstrate the presence of
- polyuria, occasional glycosuria and a constant increase of the glomerualre filtrate, 20-50% higher than healthy subjects of the same age; at this stage the urinary excretion of albumin is normal
STADIUM II
Also called "of silent nephropathy"
- Also in this phase NO symptoms are present, but, especially after physical efforts or food abuse, microalbuminuria appears. The term microalbuminuria was coined to report the urinary presence of albumin in modest but still significant concentrations from a chemical and clinical point of view
STADIUM III
Also called the stage of "incipient nephropathy"
- At this stage, microalbuminuria is permanent and occurs even in the absence of physical effort or food abuse. The glomerular filtrate is reduced, but still remains at high values; often arterial hypertension appears
STAGE IV
Also called the stage of "overt nephropathy"
- There is a frank proteinuria (> 200 µg / min), and the glomerular filtrate is reduced to frankly pathological values. Constant arterial hypertension, constant increase in creatininemia. The transition from microalbuminuria to proteinuria also marks the passage of diabetic nephropathy from the pre-clinical to the clinical phase. Symptoms and complications are those typical of the nephrotic syndrome: edema, therefore swelling especially in the face, feet and abdomen, foaming in the urine, increased susceptibility to infections, malnutrition, increased cardiovascular risk (thrombosis and hyperlipidemia ), anemia, weakness, malaise.
STAGE V
Also called uremic stage or "chronic renal failure"
- It is characterized by chronic renal failure which evolves towards terminal uremia which requires dialysis treatment. Diabetics are less tolerant of uremia than chronic uremics, so their survival is less
Diagnostic criteria
Standard urine testing is the first step in the diagnostic process and screening of diabetic nephropathy.
In order to be able to speak confidently about diabetic nephropathy it is first of all necessary to exclude the numerous causes that can alter the urinary excretion of albumin: infections, but also decompensated diabetes (occasionally elevated hyperglycemia), physical activity, urinary infection, fever, heart failure and hypertension strict. Hence the need not to limit itself to the dosage of albumin alone, but to extend the examination to the evaluation of other important parameters: urinary sediment analysis, leukocyte count, glucose and nitrite dosage ...
- MICROALBUMINURIA:> 30 mg / day or 20 µg / min or 30 µg / mg creatinine
- PROTEINURIA OR MACROALBUMINURIA: albuminuria> 300 mg / day
PLEASE NOTE: The urinary excretion of albumin shows considerable variations from day to day; for this reason the safety of finding oneself in front of a microalbuminuric patient is obtained only through the detection of high levels of albumin in at least 2 out of 3 samples collected over a period of 3-6 months.
Therapy and prevention
Preventive and therapeutic strategies to delay the onset of diabetic nephropathy and its evolution towards chronic renal failure include:
- Intensive (rigorous) control of blood glucose, whose target is represented by glycated hemoglobin percentages lower than 6-7%, to be implemented through:
- dietary control (see diet and diabetes)
- regular physical activity (see sport and diabetes)
- drug therapy (see diabetes medicines)
- Control of arterial hypertension, whose target is represented by blood pressure values around 125/75 mmHg, to be implemented through:
- dietary control (see diet and hypertension)
- regular physical activity (see sport and hypertension)
- drug therapy to be implemented with ACE inhibitors, angiotensin II receptor antagonists and / or sartans
- Restriction of caloric intake in the event of overweight or obesity; in the case of diabetic nephropathy the target is the maintenance of BMI between 20 and 25
- Restriction of protein intake in the diet (hypoproteic diet) favoring proteins of plant origin and fish, whose target is a protein intake of 0.8 g / kg (about 10% of daily calories). This dietary intervention is especially useful in tertiary prevention, to prevent or slow the evolution of the disease from the stage of overt diabetic nephropathy to that of uremia
- Abolition of smoking
- Correction of dyslipidemia, whose target is represented by LDL values lower than 100 mg / 100 ml (see: drugs for high cholesterol)
- Abstention from nephrotoxic drugs (contrast agents, antibiotics and NSAIDs such as ibuprofen, naproxen and celecoxib)
For patients who have reached the fifth stage, dialysis treatment is necessary. Isolated kidney transplantation or the joint kidney-pancreas transplantation is almost always contraindicated in type 2 diabetics due to the presence of cardiovascular alterations and other risk factors (advanced age, poor life expectancy ...) that can compromise the outcome of 'intervention.
