Acute renal failure or ARF is a condition brought about by the sudden decline of the kidneys’ ability to remove excess water from the body and filter waste products from the blood. The accumulation of these waste products in the bloodstream would lead to the symptoms of ARF which could be felt within hours, days or weeks from the onset of function loss. And the inability of the kidney to regulate fluid balance could lead to other conditions that are deleterious to the body. These conditions are reversible with the early correction of the problems, which would then insure restoration of normal blood flow to the kidneys.
Acute renal failure has three general classifications. They are prerenal ARF, renal ARF and postrenal ARF.
Prerenal ARF, which is the most common form, is caused by inadequate blood flow to the kidneys.
Major factors leading to this are hypovolemia and cardiovascular diseases. Hypovolemia or low blood volume is brought about by uncontrolled blood loss, and dehydration from various causes such as diarrhea, vomiting, use of diuretics, diabetes insipidus, burns and inadequate intake of fluid. Cardiovascular diseases such as myocardial infarction, congestive heart failure and pulmonary hypertension promotes low cardiac output and subsequently decrease renal blood flow. Other contributory factors are severe infections that reach the blood stream, improper use of antihypertensive drugs and other drugs, and anaphylactic shock.
Renal ARF or intrinsic ARF develops when important structures of the kidneys are damaged thereby promoting functional abnormalities. Factors leading to this are obstruction in the renal arteries and veins, inflammations within the kidneys’ structures, malignant hypertension, autoimmune diseases, tumors, infections, toxins and drug allergies. Most common drugs having adverse reactions to the kidneys are antibiotics and over-the-counter pain medications.
Postrenal ARF, which occurs less frequently, is caused by any obstruction in the urinary tract that prevent passage of urine. These include obstruction of the two ureters at the same time by blood clots or stones, bladder neck obstruction due to stones, tumors, prostate enlargement and infections, and narrowing at the opening of the urethra brought about by the presence of infection and inflammations.
Symptoms of acute renal failure are not specific, and could be attributed to other disease processes. These symptoms include decrease urine output, dizziness, headache, body malaise, confusion, drowsiness, fever, seizures, abdominal pain, chest pain, swelling of the ankles and legs, rashes and joint pains.
When acute renal failure is not treated early, irreversible damage to the kidneys could occur, leading to the permanent loss of their functions. When this happens, only regular dialysis or a kidney transplant could help the patient.
**The following materials were used in the preparation of this article on Acute Renal Failure: Causes, Symptoms and Complications
Harrison’s Principles of Internal Medicine, 17th Edition (2008), Chapter 273. Acute Renal Failure: Introduction
Mayo Clinic. Diseases and Conditions. Kidney Failure, acute. Retrieved October 28, 2009. Available: Mayo Clinic
