Diabetic Nephropathy

Diabetic nephropathy is a serious complication occurring in patients with diabetes characterized by Persistent albuminuria with or without a raised serum creatinine level, which is confirmed on at least 2 occasions 3-6 months apart. Progressive decline in the glomerular filtration rate and Elevated arterial blood pressure. It occurs due to uncontrolled blood sugar levels exceeding the capacity of the kidney to filter causing a toxic load on the kidneys and resulting in kidney disease. Patients with associated high blood pressure, obesity, smoking, and an individual with a family history of diabetes and kidney disease are at increased risk of developing this condition.

About 5-40% of diabetes patients develop chronic kidney disease. Both type 1 and type 2 diabetes can develop but are more common in type 2 diabetes patients. In diabetic nephropathy patients, the glomeruli and kidneys are normal or increased in size unlike in Polycystic kidney disease where their size is reduced. The occurrence of kidney disease is explained in 5 stages. Patients present with no symptoms in the initial stage. When symptoms are present the disease will be severe.

Early identification and treatment are important if left untreated can lead to chronic kidney failure. The diagnosis is based on testing the kidney function parameters which show abnormal levels. Adequate control of diabetes, lifestyle modifications, and controlling hypertension can help to delay the progression of kidney disease. When the kidney damage is severe patients require dialysis and some may require kidney transplantation.

Diabetic Nephropathy: Causes

Various factors influence the development of kidney disease in diabetes patients.

The following are the essential causes of developing diabetic nephropathy −

• Diabetes leads to kidney disease in several ways. At the onset of diabetes, blood flow into the kidneys increases, which may strain the glomeruli and lessen their ability to filter blood.

• Higher levels of blood glucose lead to the buildup of extra material in the glomeruli, which increases the force of the blood moving through the kidneys and creates stress in the glomeruli. This stress leads to gradual and progressive scarring of the glomeruli, eventually reducing the kidneys’ ability to filter blood properly.

• Long-standing diabetes patients develop this

• An individual with a family history of Diabetic nephropathy is more likely to develop it

• Inadequate Glucose Control for a longer duration or frequently

• People associated with high blood pressure fasten the damage to the kidney

• Hyperlipidemia and smoking also increase the risk of developing the condition

• During pregnancy, there is a rise in GFR which returns to normal after delivery. But hypertensive women or those with the renal disease before conception have a higher risk of progression of the disease

Diabetic Nephropathy: Symptoms

The patient with diabetic kidney disease initially does not produce any symptoms. When the symptoms are present the kidney damage is severe. The patient presents with the following symptoms −

• Swelling of the feet is pedal edema

• Swelling of the hands and face

• Trouble sleeping or concentrating

• Poor appetite

• Nausea

• Weakness

• Itching is present

• Extremely dry skin

• Drowsiness

• Abnormalities in the heart’s regular rhythm, because of increased potassium in the blood

• Muscle twitching

Diabetic Nephropathy: Risk Factors

Several factors play an essential role in the development of diabetic kidney disease which include:

• Long-standing diabetes patients of more than 10 to 15yrs are at increased risk

• Patients with both types of diabetes can develop this but type 2 diabetes mellitus patients are at increased risk

• An individual with a family history of diabetic nephropathy is more likely to develop

• Inadequate Glucose Control for a longer duration or frequently

• People associated with high blood pressure fasten the damage to the kidney

• Hyperlipidemia and smoking also increase the risk of developing the condition

• During pregnancy, there is a rise in GFR which returns to normal after delivery. But hypertensive women or those with the renal disease before conception have a higher risk of progression of the disease

• Diabetes patient with pre-existing kidney disease

Diabetic Nephropathy: Diagnosis

The diagnosis of diabetic kidney disease is mainly made based on history, and physical examination, and some investigations are required. Diagnosis is done as follows −

• History of symptoms and family history should be asked for

• Physical examination should be carried out to rule to look for changes in skin color and taps on specific areas of the patient’s body, checking for swelling of the feet, ankles, or lower legs

• Urine tests such as the Dipstick test for albumin and Urine albumin-to-creatinine ratio

• A blood test showing eGFR below 60 may indicate kidney damage and an eGFR of 15 or below may indicate kidney failure

• People with diabetes should get regular screenings for kidney disease. The National Kidney Disease Education Program recommends the following: urine albumin-to-creatinine ratio measured at least once a year in all people with type 2 diabetes and people who have had type 1 diabetes for 5 years or more. eGFR is calculated at least once a year in all people with type 1 or type 2 diabetes

Diabetic Nephropathy: Treatment

Once the kidney is involved in patients with diabetes the treatment is done as follows −

Conservative Treatment

Conservative treatment includes −

• The presence of Microalbumin in the urine indicates that treatment should be started

• Use of ACE inhibitors is essential as microalbuminuria indicates increased pressure in the kidney. BP should be managed to achieve <130/80mmHg.

• HbA1c should be managed to <6.5%.

• Reduce protein in the diet to 0.8-1.0gm/Kg body weight in early stages and to <0.8gm in later stages of CKD.

• Lipid management, non-smoking, and aspirin therapy are also helpful

• When GFR falls <60ml/min/1.73mt.sq.BSA, the person should be referred to a Nephrologist.

• When the kidney damage is severe the patients require frequent dialysis

Surgical Treatment

Advised in severe cases. When the kidney fails to function (kidney failure), transplantation of the kidney is required.

Diabetic Nephropathy: Prevention

Some of the measures that can help to prevent claudication include −

• Achieving blood glucose levels in the normal range with proper medications and diet can either delay the start or progression of Microalbuminuria to Macroalbuminuria.

• Lowering BP reduces the development of kidney disease.

• A diet with more fruits, vegetables, dietary fibers, whole grains, and other foods that are heart-healthy and lower in sodium, which often comes from salt is advised

• Regular measurement of blood sugar and HBA1C levels to keep the disease under control HbA1c should be checked at least twice a year and levels should be below 7 percent

• Regular check-ups for screening kidney disease in diabetes patients are advised.

• Regular physical activity to maintain body weight should be done

• Maintain the blood pressure under control with anti-hypertensive medicines and lifestyle modifications

• Avoid smoking

Conclusion

Diabetic kidney disease or diabetic nephropathy is a complication seen in patients with diabetes mellitus. It occurs due to uncontrolled diabetes where the high glucose levels in the blood cause the kidneys to filter blood at a higher rate than normal. Increasing glucose levels causes osmotic stress and toxic loads on the kidneys causing further damage and leading to failure at the final stage.

Patients don’t present with symptoms unless severe damage to the kidney is present, hence regular screening for kidney disease in diabetes patients is advised. Maintaining blood sugar levels and blood pressure under control along with lifestyle modifications is very important to prevent the development and progression of kidney disease.