Understanding Chronic Kidney Disease: Causes, Symptoms, and Treatment

Chronic kidney disease (CKD) is the gradual damage of kidney function that has developed over a period of time, typically at least 3 months or more. 

Chronic kidney disease can progress to severe end-stage kidney disease that can result in permanent kidney damage. When this happens, it can affect other body organs and cause complications like heart disease, high blood pressure, electrolyte imbalance, or anemia. A patient with end-stage kidney disease may ultimately need dialysis to maintain their kidney function. 

In this blog, we will discuss chronic kidney disease in detail, including its causes, symptoms, diagnosis, treatment, prevention, and more. 

What Is Chronic Kidney Disease?  

Our kidneys are responsible for filtering blood and other waste products out of the body in the process of producing urine. CKD occurs when your kidneys are damaged, hence unable to filter toxins, waste products, and other excess fluids from the body. 

This leads to the accumulation of abnormal levels of fluids (causing edema), electrolytes (such as high level of potassium or phosphorus), and wastes in the body. 

Stage 5 is the most severe form of chronic kidney disease, where the kidneys have completely failed or become permanently damaged, and dialysis at this point is necessary to maintain kidney function. 

Dialysis is a procedure to remove excess water, toxins, and solutes from the blood through a machine. Patients on dialysis may need to visit a dialysis center 2 – 3 times each week, often for 4 – 5 hours each session. Unfortunately, this can limit participation in work, family, and social activities.

Symptoms of Chronic Kidney Disease 

The symptoms of CKD rarely appear until the disease has advanced. This is because the condition progresses slowly and develops over time. The common signs and symptoms of chronic kidney disease, depending on the severity, include: 

• Fatigue
• Nausea
• Swelling of ankles and feet
• Decreased urination
• Weakness
• Hypertension (high blood pressure)
• Breathing difficulties
• Chest pain
• Loss of appetite

Diagnosis of Chronic Kidney Disease

There are multiple tests for diagnosing renal failure, but blood and urine tests are the initial tests to assess chronic kidney disease. Imaging studies, such as ultrasound, X-rays, or kidney biopsy, can also be used to identify the cause of chronic kidney disease. Some of these tests are described in further detail below:

Glomerular Filtration Rate (GFR)  

A glomerular filtration rate is a blood test that measures the amount of blood filtered by the kidneys per minute. Therefore, if the kidneys are filtering less blood it helps identify kidney damage. The glomerular filtration rate also indicates the stage of chronic kidney disease. It measures the efficiency of kidney functioning. If there is a reduction in your GFR level, your doctor may refer you to a nephrologist (kidney specialist).

Creatinine Clearance (CrCl)

Creatinine clearance is a test that evaluates the level of creatinine in the blood or urine. Creatinine is a byproduct or waste product of the body that is normally filtered by the kidneys and excreted through the urine. A high amount of creatinine in the blood may indicate kidney damage. 

Blood Urea Nitrogen (BUN) 

Like creatinine, urea nitrogen is another waste product of the body that has to be filtered by the kidneys and excreted through the urine. Blood urea nitrogen is a blood test that measures the amount of the waste product and urea nitrogen present in the blood. 

A healthy kidney filters urea nitrogen and excretes it out through urine. But if the kidneys are damaged, a high level of urea nitrogen will be present in the blood, indicating signs of kidney damage. 

Ultrasound and Kidney Biopsy

An ultrasound is an imaging test that shows a picture of the kidneys and how they are functioning. Size of the kidney, cysts in the kidney, or abnormal kidney mass may be seen on the ultrasound.

While not frequently performed, a kidney biopsy is a procedure that removes a small piece of tissue from the kidney by inserting a thin needle in the skin. The tissue is examined under a microscope to determine the extent of kidney damage. This is done to possibly determine the etiology of the kidney disease.

Stages of Chronic Kidney Disease 

There are five stages of chronic kidney disease, where stage 1 is the least severe and stage 5 is the most severe form of kidney failure. The 5 stages are commonly defined on the basis of the values of estimated glomerular filtration rate (eGFR).

Stage 1  

Stage 1 chronic kidney failure is when the patient has normal levels of eGFR (above 90 ml/minute), but other tests have indicated signs of kidney damage.

Stage 2  

Stage 2 is when the patient has other signs of kidney damage with slightly decreased levels of eGFR around 60 – 89 ml/min.

Stage 3 

An eGFR ranging from 30 – 59 ml/min with mild to moderate signs of renal damage is defined as stage 3 chronic kidney disease.

Stage 4  

An eGFR value of 15 – 29 ml/min with severe loss of kidney function is indicated as stage 4 chronic kidney disease.

Stage 5 

Stage 5 is the last and most severe form of kidney failure, where the eGFR value is less than 15 ml/minute. In this stage, dialysis or kidney transplant becomes necessary, depending on the patient’s condition.

Treatment 

The treatment of CKD depends on the severity and stage of the disease: 

• For early stages of kidney disease, medications and lifestyle modifications (dietary and physical activity) are recommended.
• For advanced chronic kidney disease, commonly stage 4 and stage 5, dialysis and kidney transplants are done to restore kidney functioning.

Risks of Chronic Kidney Disease 

The risk factors of chronic kidney disease include: 

Age. Kidney function decreases with age in both men and women. In patients over the age of 75, more than half of the patients may have Stage 3 to 4 kidney disease.

High blood pressure and high blood sugar. Both increased levels of blood pressure and blood sugar can damage the blood vessels and nephrons of your kidneys. These blood vessels can become narrowed and clogged. This causes dysfunction of the kidney and as a result, it doesn’t filter blood and waste materials properly. 

A family history of kidney failure or kidney disease. 

Smoking. If you smoke, there is a 2.5 times higher likelihood of developing kidney disease.

Obesity. Being overweight or obese can put excessive pressure on your kidneys to work harder to filter blood and waste materials out of the body. With time, the extra burden can damage the kidney and its ability to function properly. Moreover, obesity increases the risks of hypertension and diabetes, which are the two leading causes of chronic kidney disease.

Prevention of Chronic Kidney Disease 

Prevention of chronic kidney disease simply means preventing its risk factors, for example: 

Yearly Checkups and Tests

To ensure that your kidneys are functioning properly, get your tests and checkups done yearly especially if you are at high risk for developing kidney disease. 

Hypertensive, obese, and diabetic patients, plus people with a family history of renal failure and elderly individuals, are at high risk of developing chronic kidney disease. 

Tests like GFR, serum creatinine, and X-rays can be done to evaluate any initial problem with the kidneys. 

Dietary Modifications 

For managing blood pressure, blood sugar, and controlling weight, dietary and lifestyle modifications are most important. 

Dietary modification should include restricting salt intake to less than 2,300 mg per day and not more than 24 – 36 grams of sugar per day. 

Exercise 

In addition to dietary modifications, exercise is equally important, especially for people at risk of chronic kidney disease. 

Moderate-intensity exercise for at least half an hour five times a week not only controls weight but also reduces blood pressure, managing the risks and progression of chronic renal failure. 

Even if you have CKD, managing blood pressure, weight, and blood sugar with exercise and dietary modifications can help prevent further complications.