Acute renal failure
Alternative names: Acute kidney injury, Kidney failure, Renal failure, ARF
Overview of acute renal failure
Acute renal failure (ARF) refers to the rapid decrease (within a few days to weeks) in the functioning of the kidneys resulting in an inability to clear nitrogenous wastes, concentrate urine, conserve electrolytes and maintain fluid balance in the body. This leads to accumulation of these waste products in the body, which may secondarily affect the normal functioning of the body.
Acute renal failure may be caused due to various factors that may affect the normal functioning of the kidneys at various levels such as entry, within the kidneys or at the exit.
Acute renal failure is noticed in about 1–5% of patients admitted to the hospital and in about 15–20% of patients admitted in intensive care units (ICUs). It may be mortal if left untreated.1,2
Signs and Symptoms of acute renal failure
A wide array of signs and symptoms may be noticed based on the causative factors, which are responsible for ARF.
Some of these features may also be helpful in pointing out the underlying cause of ARF. Symptoms related to the underlying disorders may be the only initial features of renal failure.
The specific symptoms of ARF vary with the severity of the condition and can include:
- Decreased urination (oliguria)
- Weight gain
- Swelling of the feet, ankle (ankle edema) and legs
- Loss of appetite (anorexia)
- Nausea and vomiting
Causes of acute renal failure
Diagnosis of acute renal failure
The diagnosis of the cause of ARF is based on
- Comprehensive review of the history of the condition
- The signs and symptoms observed
- Physical examination
- Specific investigations
A history of burns, diarrhea, consumption of certain medications or other similar features that result in excessive fluid loss can project the pre-renal cause while some of the symptoms such as fever can point at an infectious cause.
The doctor may perform a physical examination to confirm or rule out the underlying disorders that may have resulted in ARF.
The list of laboratory tests can include various tests such as
- Complete blood cell count
- Estimation of levels of blood urea nitrogen and creatinine
- Urinalysis with microscopy and estimation of urine electrolytes
Kidney function tests
These tests are useful in pointing out the cause of renal failure and also assess the severity of the condition.
Following imaging studies may be advised in certain instances along with renal biopsy.
- Doppler studies
- Nuclear scans
- Renal angiography
Treatment of acute renal failure
The main aims of the treatment are to prevent death, remove the cause of renal failure and to prevent permanent damage to the kidneys.
The dosing schedules of the medications that would have caused ARF are readjusted. The underlying conditions or disorders are treated appropriately.
An increase in the potassium levels in the body (hyperkalemia) is one of the main concerns and this may be rectified with the administration of medications such as insulin with glucose, β2-adrenergic agonists or sodium bicarbonate.
Other appropriate medications based on the causative factor and the severity of the condition may be administered. Hemodialysis may be advised in severe cases of hyperkalemia.
The affected individual is usually advised to restrict the water and fluid intake according to the level of functioning of the kidneys. A diet rich with carbohydrates and low in protein, salt and potassium is recommended in order to prevent the load on the kidneys.
With effective treatment, the kidneys can return to their normal functioning ability however this is dependent on various factors such as the age of the individual, severity of the underlying condition and the damage to the kidneys.3,4
Complications of acute renal failure
The most severe complication in cases of ARF is death. If left untreated, ARF can progress to become a long-term disorder termed as chronic renal failure that may further be associated various other complications and permanent damage to the kidneys.
Altered functioning of the heart and nervous systems are some of the other complications.
Prevention of acute renal failure
Although ARF cannot be prevented in many instances, proper management of cases involving burns and other causes of fluid loss can prevent the occurrence of ARF in such individuals. Careful administration of drugs that are toxic to the kidneys can prevent kidney damage.
Written by: healthplus24.com team
Date last updated: December 10, 2014
You May Also Like To Read
1. Schrier RW, Wang W, Poole B, Mitra A. Acute renal failure: Definitions, diagnosis, pathogenesis, and therapy. J Clin Invest. 2004; 114: 5–14.
2. Kellum J, Leblanc M, Venkataraman R. Acute renal failure. Am Fam Physician. 2007; 76(3).
3. Needham E. Management of acute renal failure. Am Fam Physician. 2005; 72: 1739–1746.
4. Fry AC, Farrington K. Management of acute renal failure. Postgrad Med J. 2006; 82; 106–116.