Acute Renal Failure

Acute kidney injury (AKI) is a sudden episode of kidney failure or kidney damage that happens within a few hours or a few days. AKI causes a build-up of waste products in your blood and makes it hard for your kidneys to keep the right balance of fluid in your body. Although ARF can be life-threatening while it lasts, kidney function usually returns after the cause of the kidney failure has been treated. In many patients, ARF is not associated with any permanent damage. However, some patients may recover from ARF and subsequently develop CKD.

Signs of Acute Kidney Failure

Symptoms include decreased urinary output, swelling due to fluid retention, nausea, fatigue, drowsiness and shortness of breath. Sometimes symptoms may be subtle or may not appear at all.

Causes of Acute Kidney Failure

Most cases of AKI are caused by reduced blood flow to the kidneys, usually in someone who’s already unwell with another health condition. It’s most common in those who are critically ill and already hospitalized. AKI often occurs due to multiple processes. The most common cause is dehydration and sepsis combined with nephrotoxic drugs, especially following surgery or contrast agents. The causes of acute kidney injury are commonly categorized into prerenal, intrinsic, and postrenal. dehydration, among other things.

Direct trauma to the kidney — from a car accident, for example — can cause acute kidney failure. So can obstruction in the ureters, which leave your body unable to pass waste through your urine.

Treating Acute Kidney Failure

In addition to addressing the underlying cause, treatments include fluids, medication, and dialysis.

Chronic Kidney Disease (CKD)

The two kidneys are bean-shaped organs located just below the rib cage, one on each side of the spine. Every day, the two kidneys filter about 120 to 150 quarts of blood to produce about 1 to 2 quarts of urine, composed of wastes and extra fluid.

Their main job is to filter wastes and excess water out of your blood to make urine. They also keep the body’s chemical balance, help control blood pressure, and make hormones.

CKD is the slow, gradual loss of kidney function which means your kidneys cannot filter blood like they should. This damage can cause wastes to build up in your body. Blood tests are necessary to determine if you are at risk for chronic kidney disease. The most commonly used blood test marker for kidney function is “creatinine”. However, creatinine can be an imperfect marker for patients that are in the early stages of kidney failure (in general, a normal creatinine is around 1.0 or below). To help screen patients for early kidney disease, an additional test is added to any chemistry panel checking kidney function called “eGFR”, or “Estimated Glomerular Filtration Rate”. This test is a calculated and estimated test of kidney function, and must be interpreted as such based on the patient’s age, gender, muscle mass, and general health. A lower eGFR suggests that your kidneys do not function as well as they should. Based on the eGFR your PCP may refer you to see a kidney specialist or nephrologist.

The single biggest cause of kidney failure is diabetes. It causes almost half of all kidney failure in the US. When diabetes leads to significant kidney damage, this is called diabetic nephropathy

Hypertension, or high blood-pressure, is the second leading cause of kidney disease. Diabetes and hypertension share similar risk factors, like obesity, and unhealthy diet, and a lack of exercise. This means that the two ailments often come together — which can increase your risk for kidney disease.

African Americans, Hispanics, and American Indians are at high risk for developing kidney failure. This risk is due in part to high rates of diabetes and high blood pressure in these communities.

There are many other causes of kidney disease:

· Disease that cause inflammation of the filtering units to your kidneys (glomerulonephritis).

· Inherited diseases such as polycystic kidney disease

· Congenital malformations.

· Certain medications such as NSAIDs that may be toxic or may cause inflammation in your kidneys.

· Conditions that obstruct the urinary flow from your kidneys such as kidney stones, enlarged prostates and tumors.

· Recurrent urinary infections during childhood or sometimes as an adult

CKD progresses in 5 stages, with stage 5 being the most severe. It entails near total failure of your kidneys and is otherwise known as end stage renal disease (ESRD). The symptoms of the early stages of CKD are very subtle and difficult to detect — so it’s important to get screened for it if you have any of the risk factors mentioned above.

Five Stages of Kidney Disease

· Stage 1 with normal or high GFR (GFR > 90 mL/min)

· Stage 2 Mild CKD (GFR = 60-89 mL/min)

· Stage 3A Moderate CKD (GFR = 45-59 mL/min)

· Stage 3B Moderate CKD (GFR = 30-44 mL/min.

· Stage 4 Severe CKD (GFR = 15-29 mL/min)

· Stage 5 End Stage CKD (GFR <15 mL/min)

 

 

Some forms of CKD can be controlled or slowed down. For example, diabetic nephropathy can be delayed by tightly controlling blood glucose levels and using certain medications such as ACE inhibitors and ARBs to reduce proteinuria and control blood pressure. But CKD cannot be cured. In many cases, CKD leads to total kidney failure.

 

Total Kidney Failure (End Stage Renal Disease, ESRD)

To stay alive, a patient with total kidney failure must go on dialysis—hemodialysis or peritoneal dialysis—or receive a new kidney through transplantation. Patients with CKD who are approaching total kidney failure should learn as much about their treatment options as possible so they can make an informed decision when the time comes. With the help of dialysis or transplantation, many people continue to lead full, productive lives after reaching total kidney failure.

Points to Remember

· The kidneys filter waste and extra fluid from the blood.

· The filtering process takes place in the nephron, where microscopic blood vessel filters, called glomeruli, are attached to fluid-collecting tubules.

· A number of different disease processes can damage the glomeruli and thereby cause kidney failure. Glomerulonephritis and glomerulosclerosis are broad terms that include many forms of damage to the glomeruli.

· Some forms of kidney failure can be slowed down, but scarred glomeruli can never be repaired.

· Treatment for the early stages of kidney failure depends on the disease causing the damage.

Early signs of kidney failure include blood or protein in the urine and swelling in the hands, feet, abdomen, or face. Kidney failure may be silent for many years.