Acute renal failure

From ArticleWorld

Acute renal failure involves the sudden shutdown of kidney function due to multiple causes. The condition is usually serious and results in the accumulation of toxic nitrogen-based waste products in the blood stream. The blood becomes more acidic, affecting all parts of the body, potassium levels can rise and the body can retain large amounts of fluid. Fortunately, if treated promptly, the kidney can recover its function and return to normal.

Causes

Acute renal failure can be a result of problems originating before the kidney, within the kidney or after the kidney itself. “Pre-renal” conditions include the sudden or prolonged loss of blood pressure as in a case of traumatic shock, a serious blood infection, heart attack or severe dehydration. The kidneys need blood flow to function and, in very low blood pressure situations, the kidneys cannot filter blood.

Whenever the blood vessels leading to or from the kidneys are disrupted, the kidneys can fail. Blood clots, like those that cause heart attacks or strokes, can cut off the blood supply in the renal artery, leading to failure of the affected kidney. Similarly, a blood clot in the renal vein can cause disruption in the smooth flow of blood to a kidney that will ultimately shut down.

There are many “renal” causes of acute renal failure. An infection of the kidney can shut it down. If a large amount of muscle is damaged, such as with serious trauma, some medications or the street drug, ecstasy, a condition known as rhabdomyolysis occurs. This floods the kidney with breakdown products of muscle damage and can cause the kidneys to shut down.

Certain medications, such as lithium, anti-inflammatory medications, some antibiotics or antifungals or intravenous contrast medium, can cause acute failure of the kidneys. Excessive red blood cell breakdown floods the kidneys with hemoglobin, which damages the tubules in the kidneys and shuts the kidney function down.

Multiple myeloma can increase the amount of calcium in the blood and this calcium can combine with other molecules and “precipitate” (turn into solid form) in the kidneys. This can cause the kidneys to fail. Another condition, known as acute glomerulonephritis, affects the filtration ability inside the kidney itself. This condition can be a result of systemic lupus erythematosis, Wegener’s granulomatosis, Goodpasture’s syndrome and several genetic diseases.

“Post-renal” causes of acute renal failure are those that disrupt the flow of urine out of the kidneys. Kidney stones blocking the ureters, blockage of the bladder flow due to a bladder stone or enlargement of the prostate can result in acute renal failure.

Treatment

The treatment of acute renal failure involves both support of the body and treatment of the underlying cause of the problem. If the problem is due to severe hypotension, restoring normal blood pressure often solves the problem. Treating any kidney infection aggressively will restore function in most cases. While the patient is being evaluated and the underlying cause treated, the person may require dialysis, careful management of the acidity of the blood and monitoring of the potassium levels. Depending on the cause of the renal failure, recovery can be complete, partial or not at all.