Acute renal failure is the sudden loss of the kidneys' ability to filter waste products from the bloodstream, according to MayoClinic.com. Also known as acute kidney injury, it usually occurs in conjunction with another medical condition such as diabetes, heart failure, liver diseases, blood vessel blockages, kidney diseases and high blood pressure.
Prerenal Causes
Prerenal causes of acute renal failure refer to those conditions that decrease the kidney's blood supply, according to the American Academy of Family Physicians, or AAFP. This can be brought about by changes that affect the entire circulatory system such as low blood pressure, low blood volume, or heart failure. In other cases, it can be caused by damage to, or narrowing of, the blood vessels immediately connected to the kidney; renal vein thrombosis, whereby a blood clot forms in the renal vein that drains the kidney of blood; and renal artery stenosis, whereby the artery supplying the kidney narrows, restricting blood flow.
Intrinsic Causes
Intrinsic causes denote those cases when kidney failure is caused by damage to the organ itself. Some of the most common causes include acute tubular necrosis, or ATN; glomerulonephritis; and acute interstitial nephritis, or AIN. Each of these conditions refers to damage to a specific part of the kidney, and each one is capable of bringing about acute renal failure, according to MayoClinic.com.
ATN is of the most common causes of kidney failure. It involves the death of cells composing the tubule that bring urine to the ureters. ATN may be brought about by exposure to a toxic substance, or when the renal cells themselves fail to get enough oxygen.
Glomerulonephritis is a condition in which the small blood vessels in the kidneys are inflamed. This can be caused by a large number of factors, including bacterial, parasitic or viral infections, diabetes, drugs, or systemic diseases affecting the patient.
AIN, on the other hand, denotes a form of inflammation affecting the interstitium, or connective tissue, surrounding each kidney's tubules. It is commonly caused either by a reaction to medications or an infection.
Postrenal Causes
Postrenal causes of acute kidney failure refer to those that stem from a blockage of the urinary tract, notes the American Academy of Family Physicians. Related conditions and diseases that cause blockages include prostate cancer, cervical cancer, colon cancer, kidney stones, bladder stones, enlarged prostate and obstructed urinary catheter. Typically, postrenal causes are more easily reversed than intrinsic or prerenal causes. The recovery of kidney function is inversely proportional to how long the urinary tract remains blocked.
Treatment
Treatment of acute kidney failure centers on correctly addressing the cause, then working to return normal renal function and stopping waste products and fluids from accumulating in the system as the organs recuperate, according to MedlinePlus.
Antibiotics may be prescribed in case the cause is due to an infection. Diuretics may also be given to eliminate the excess fluid in the kidneys. Dialysis may be required if the patient's potassium levels are excessively high, if the patient stops urinating, or experiences a change in mental status. Typically, patients will rely on a diet low in protein, sodium and potassium, and high in carbohydrates. This is so that the kidneys won't be overly stressed in their task of filtering toxins out.
Prevention
It is very difficult, if not impossible, to prevent or predict acute kidney failure, according to MayoClinic.com. However, it is still a good idea to take precautions. Patients with ailments that increase the risk of acute renal failure should consult with their doctors to control or manage these conditions. In addition, when taking over-the-counter medication such as ibuprofen, aspirin and acetaminophen, follow the dosage instructions carefully. Excessive dosages can also increase the risk of renal failure.
