Chronic Kidney Disease (CKD)

Overview

Chronic kidney disease, also known as chronic renal disease or CKD, is a condition characterized by a gradual loss of kidney function over time. It includes conditions that damage your kidneys and reduce their ability to keep you healthy by filtering out wastes and excessive fluids from your blood which are then removed in your urine. If kidney disease worsens, wastes can build to high levels in your blood and make you feel sick.

Symptoms

Signs and symptoms of chronic kidney disease develop over time if kidney damage progresses slowly. Depending upon the severity, symptoms of kidney disease may include:

Nausea or vomiting
Loss of appetite
Fatigue and weakness
Trouble sleeping
Urinating more often, especially at night
Difficulty in concentrating
Muscle cramps
Swollen feet and ankles
Dry, itchy skin
Puffy eyes
High blood pressure (hypertension)
Shortness of breath
Chest pain
Skin darkening

Causes

Chronic kidney disease develops when a disease or condition harms kidney function, causing kidney damage to worsen over several months or years. Diabetes and high blood pressure, or hypertension, are responsible for two-thirds of chronic kidney disease cases. Other diseases and conditions that cause chronic kidney disease include:

Diabetic nephropathy, caused by type 1 or type 2 diabetes
Hypertensive nephrosclerosis, caused by high blood pressure
Glomerulonephritis, a type of kidney disease that causes inflammation of the kidney’s filtering units (glomeruli)
Interstitial nephritis, an inflammation of the kidney’s tubules and surrounding structures
Membranous nephropathy, a disorder in which body’s immune system attacks the waste-filtering membranes of the kidney
Polycystic kidney disease, a genetic disorder that causes several fluid-filled cysts to grow in kidneys, and reduces the ability of kidneys to function
Prolonged obstruction of the urinary tract, from conditions such as enlarged prostate, kidney stones or some cancers
Vesicoureteral reflux, a condition in which urine flows backward from the bladder to the kidneys
Recurrent kidney infection, also called pyelonephritis
Other inherited kidney diseases

Risk Factors

Factors that can increase your risk of developing chronic kidney disease include:

Diabetes
High blood pressure
Heart (cardiovascular) disease
Smoking
Obesity
Being Africa-American, Hispanic, Native American, Asian Pacific Islanders, and American Indians
Family history of kidney disease
Abnormal kidney structure
Older age (over 60 years)
Frequent use of medications that can damage the kidneys (such as aspirins and ibuprofen)

Complications

Chronic kidney disease can affect nearly all parts of your body. Some of the complications of chronic kidney disease include:

Fluid retention, which could lead to swelling in arms and legs, or fluid in lungs (pulmonary edema)
High blood pressure
Gout
Anemia
Heart disease, increased risk of stroke and heart attack
Weak bones and a higher risk of bone fractures
Rise in potassium levels in your blood (hyperkalemia), which weaken your heart’s functionality and can be life-threatening
Decreased sex drive, erectile dysfunction, or reduced fertility
Damage to your central nervous system, which can cause difficulty concentrating, personality changes or seizures
Decreased immune response, which increases your risk of infection
Pregnancy complications
Irreversible damage to your kidneys (end-stage kidney disease), leading to either dialysis or a kidney transplant for survival

Diagnosis and Tests

As the first step towards diagnosis of kidney disease, your medical provider discusses your personal and family medical history with you. In addition to other things, your provider might inquire about whether you have been diagnosed with high blood pressure, if you have taken any medication that might impair kidney function, if you have noticed changes in your urinary habits and whether you have family members who are suffering with kidney disease.

Your healthcare provider will perform blood tests, a urine test and will also check your blood pressure to determine how severe your kidney disease is. Tests might include:

Blood tests. Kidney function tests look for the level of waste products, such as creatinine and urea, in your blood.
Urine tests. Analyzing a sample of your urine can reveal irregularities that point to chronic kidney failure and help find the cause of chronic kidney disease.
Glomerular filtration rate (GFR). To examine how efficiently your kidneys are filtering blood – how many milliliters per minute your kidneys are filtering. Your GFR is used to determine the stage of your kidney disease.
Imaging tests. Your doctor might use ultrasound to assess your kidneys’ structure and size. Other imaging tests such as MRI and CT scan might be used in some cases.
Kidney biopsy. Your doctor might recommend a kidney biopsy, which involves removing a sample of kidney tissue. Kidney biopsy is usually done using local anesthesia, and with a long, thin needle that is inserted through your skin and into your kidney. The biopsy sample is sent to a lab for examination and to help determine the cause of your kidney problem.

Treatment and Medication

Treatment for chronic kidney disease focuses on slowing the progression of kidney damage, usually by controlling the cause. Though some types of kidney disease can be treated but, chronic kidney disease has no cure. In such cases, even controlling the cause might not keep kidney damage from progressing. Chronic kidney disease can progress to end-stage kidney failure, which is fatal without artificial filtering (dialysis) or a kidney transplant.

Depending on the cause of your kidney disease, you provider may prescribe one or more medications. These medications may include:

High blood pressure medications. An angiotensin-converting enzyme (ACE) inhibitor or an angiotensin receptor blocker (ARB) to lower your blood pressure.
Medications to relieve swelling. A diuretic to help your body eliminate extra fluid.
Medications to lower cholesterol levels. Your doctor might recommend medications called statins to lower your cholesterol.
Medications to treat anemia. Supplements of the hormone erythropoietin are prescribed to build red blood cells if you are anemic.
Medications to protect your bones. Vitamin D and calcium supplements (calcitriol) to prevent weak bones and risk of fracture.
Phosphate binder. If your kidneys can’t eliminate phosphate.

Your provider might recommend regular follow-up testing and check-ups to see whether your kidney disease remains stable or progresses.

Prevention

Regular check-up with your provider throughout your life is a healthy way of preventing kidney disease. One in every three people in the United States is at risk for kidney disease. Following lifestyle modifications may help prevent it:

Keep your blood sugar level under control (for diabetics).
Avoid taking painkillers and other medications that may worsen your kidney disease.
Keep your blood pressure level under control.
Consult a registered dietitian to make healthy diet modifications. These may include limiting the intake of protein, sodium (salt), potassium and eating foods that reduce blood cholesterol levels.
Avoid smoking.
Treat anemia (if present).
Exercise every day and adopt an active lifestyle.
Maintain a healthy weight.

Prognosis

If you are diagnosed with kidney disease, you can still live a productive home, work life, and enjoy time with your family and friends. To have the best outcome possible, it is important for you to actively take part in your treatment team.

Early detection and appropriate treatment are important in slowing the disease progression, with the goal of preventing or delaying kidney failure. You will need to keep up with your medical appointments, take your medications as prescribed, eat a healthy diet, monitor your blood pressure, and blood sugar level.