- Acute Kidney Injury (AKI)
- Chronic Kidney Disease (CKD)
- Acute-on-Chronic Renal Failure (AoCRF)
Acute Kidney Injury (AKI) was also known as Acute Renal Failure (ARF) earlier. It is a rapid progressive loss of renal function, which can be characterized by decreased urine production (Oliguria) i.e.- as less as 400 ml per day in adults. AKI could be the result of variety of causes, generally classified as pre-renal, intrinsic and post-renal. Dialysis may be necessary, while the identification and treatment of AKI is progressed.
Chronic Kidney Disease (CKD) develops slowly and show few initial symptoms. The affects of CKD are normally irreversible. It is a progressive loss of renal function over a period of months or years. The symptoms of worsening kidney function are unspecific, and might include feeling generally unwell and experiencing a reduced appetite. Often, chronic kidney disease is diagnosed as a result of screening of people known to be at risk of kidney problems, such as those with high blood pressure or diabetes and those with a blood relative with chronic kidney disease. Chronic kidney disease may also be identified when it leads to one of its recognized complications, such as cardiovascular disease, anemia or pericarditis (inflammation of the of the pericardium – the fibrous sac surrounding the heart).
Acute-on-Chronic Renal Failure (AoCRF) It is a combination of Acute Kidney Injury alongwith Chronic Kidney Disease. The acute part of the AoCRF is reversible and the Chronic part may be irreversible.
The most common cause of CKD is diabetic nephropathy, hypertension and inflammation of small blood vessels in the kidneys. In addition, certain geographic areas have a high incidence of HIV nephropathy. Basically the kidney diseases have been classified according to the part of the renal anatomy that is involved.
Acute Kidney Injury/Acute Renal Failure
Acute kidney failure usually occurs as the result of a sudden interruption in the blood supply to the kidney, or as a result of a toxic overload of the kidneys. Some causes of acute failure include accidents, injuries or complications from surgery where the kidneys are deprived of normal blood flow for an extended period of time. Heart-bypass surgery is an example of a situation in which the kidneys receive reduced blood flow.
Drug overdoses, whether accidental or from chemical overloads of drugs such as antibiotics or chemotherapy, may also cause the onset of acute kidney failure. The kidneys can often recover from acute failure, allowing the patient to resume a normal life, unlike in chronic kidney disease. People suffering from acute failure require supportive treatment until their kidneys recover function, and they often remain at an increased risk of developing future kidney failure.
Chronic Kidney Disease
There are many causes of CKD. The most common cause is diabetes mellitus. The second most common cause is long-standing and uncontrolled hypertension. Polycystic kidney disease is also a well known cause of chronic kidney disease. The majority of people afflicted with polycystic kidney disease have a family history of the disease. Many other genetic illnesses also affect kidney function. Overuse of some common drugs, such as aspirin, ibuprofen, cocaine and acetaminophen can also cause chronic kidney damage.
Symptoms of kidney disease can vary from person to person. Some people with kidney disease may not even feel sick, or they may not notice their symptoms. If the kidney function fails, there is abnormal rise in the levels of nitrogen-containing compounds, such as urea, creatinine and other nitrogen rich compounds in the blood. This condition is termed as azotemia. Mild levels of azotaemia may produce little or no symptoms, but if the kidney failure continues then symptoms will become noticeable (if the failure is of sufficient degree to cause symptoms). Renal failure accompanied with noticeable symptoms is termed uremia.
Symptoms of kidney failure include:
- High levels of urea in the blood, which can result in:
- Vomiting and/or diarrhea, which may lead to dehydration
- Weight loss
- Nocturnal urination
- Foamy or bubbly urine
- More frequent urination, or in greater amounts than usual, with pale urine
- Less frequent urination, or in smaller amounts than usual, with dark coloured urine
- Blood in the urine
- Pressure, or difficulty urinating
- A build up of phosphates in the blood that diseased kidneys cannot filter out may cause:
- Bone damage
- Muscle cramps (caused by low levels of calcium which can cause hypocalcaemia)
- A build up of potassium in the blood that diseased kidneys cannot filter out (called hyperkalemia) may cause:
- Abnormal heart rhythms
- Muscle paralysis
- Failure of kidneys to remove excess fluid may cause:
- Swelling of the legs, ankles, feet, face and/or hands
- Shortness of breath due to extra fluid on the lungs (may also be caused by anemia)
- Polycystic kidney disease, which causes large, fluid-filled cysts on the kidneys and sometimes the
liver, can cause: Pain in the back or side.
- Healthy kidneys produce the hormone erythropoietin which stimulates the bone marrow to make oxygen-carrying red blood cells. As the kidneys fail they produce less erythropoietin resulting in fewer red blood cells being produced to replace the natural breakdown of old red blood cells. As a result the blood carries less haemoglobin which is known as anemia. This can result in:
- Memory Problems
- Difficulty Concentrating
- Feeling tired and/or weak
- Low Blood Pressure
- Fluid volume overload – symptoms may range from mild edema to life-threatening pulmonary edema
- Metabolic acidosis, due to accumulation of sulfates, phosphates, uric acid etc. This may cause altered enzyme activity by excess acid acting on enzymes and also increased excitability of cardiac and neuronal membranes by the promotion of hyperkalemia due to excess acid (acidemia).
- People with chronic kidney disease suffer from accelerated atherosclerosis and are more likely to develop cardiovascular disease than the general population. Patients afflicted with chronic kidney disease and cardiovascular disease tend to have significantly worse prognoses than those suffering only from the latter.
- Other Symptoms include:
- Appetite loss, a bad taste in the mouth
- Difficulty Sleeping
- Darkening of Skin
- blood pressure is increased due to fluid overload and production of vasoactive hormones, increasing one’s risk of developing hypertension and/or suffering from congestive heart failure.
Although every organ of the body is equally important but the role of kidney is of utmost importance because it filters the entire toxins generated in the human body. Human body is the biggest chemistry lab; every action/reaction is the result of some or the other chemical reaction. The kidney failure results in a chemical misbalance in the body, which can be the cause of numerous diseases and organ failure.