Key Differences Between Acute and Chronic Renal Failure
We have two kidneys in our bodies; they are our natural detoxification machines. They help us by purifying our blood and removing unwanted by-products from the blood. The removed waste material is eliminated from the body via urine. However, the kidneys, just like any other organ, may fail and lead to the failure of the whole body. This medical condition is called Kidney Failure or Renal Failure. A typical condition of Kidney Failure is characterised by the diminished functionality of the kidneys by, at least, 15%. There are several reasons for kidney failure; we shall discuss the causes of kidney failure in detail in the following paragraph.
Causes
In most cases, the biggest cause of the failure of the kidneys is infections, especially long-term ones. People having medical conditions like diabetes mellitus and hypertension are the ones most likely to develop renal failure. Other problems like accidents, post-surgery complications, drug overdose, chemical overload in the body, namely from antibiotics, chemotherapy etc. are also some known causes of Renal Failure.
Types of Renal Failure
There are two categories of Kidney Failure, viz., Acute Renal Failure and Chronic Renal Failure.
Acute Renal Failure Symptoms: In this condition, the kidney suddenly stops the process of blood filtration. There are symptoms of this form of kidney failure; internal bleeding, confusion, high blood pressure, swelling in limbs and face and seizures are some common ones.
Subtypes in Acute Renal Failure: (1) Prerenal Acute Kidney Failure, (2) Intrinsic Acute Renal Injury, and (3) Post-Renal Intrinsic Injury.
Prerenal Acute Kidney Failure: In this type of kidney failure, the flow of blood is reduced or blocked. Thereby, there is no damage or injury inside the kidney. It may be caused by some common reasons like gastroenteritis, vasodilation due to drug reaction, active hypovolemia sepsis, anaphylaxis or allergic reaction, lowered cardiac output, Addisonian crisis, cerebral salt wasting, protein-losing enteropathy, change in the dynamics of the blood flow due to dehydration (altered haemodynamics), restricted blood flow due to trauma, surgery &c.
Intrinsic Acute Renal Injury: it is caused due to damage to the nephrons (structural and functional unit in the kidney). The problem is complex and may not be the causative but the secondary factor for the failure of kidneys. The Intrinsic Acute Renal Injury is also known to cause tubular necrosis.
Post-Renal Intrinsic Renal Injury: This type of failure of the kidneys is characterised by the restriction of urine from the kidney. This restriction of urine applies pressure on the kidney and causes internal injury or damage to the nephrons or posterior urethral valves. It may also lead to urethral stricture or narrowing, haemorrhagic cystitis, i.e., obstruction of the bladder due to blood clots, and kidney stones formation.
Chronic Renal Failure: It is a slow and progressive failure of the kidneys. The symptoms of this form of a kidney disorder are not apparent until the kidney functions fall below a mark of 20%. There are typical signs of this type of kidney failure, namely nausea, hypertension, seizures, vomiting, short breaths, pain in the chest, fatigue, headache and itching.
Symptoms of Kidney Failure
The slow progression of Chronic Renal Failure may make its diagnosis difficult. In most cases, the problem is not diagnosed until both the kidneys reach an irreversible level of failure. The most frequently noticed symptoms are diarrhoea, insomnia, rashes, fever, vomiting, cramps in the muscles, loss of appetite, frequent urination, obstructed breathing, nausea, back and abdominal pains, swelling in the lower body namely in the feet and ankles.
Prevention and Treatment
Due to the severe nature of the disease, prevention is very important. In some cases the likelihood of the onset of the disorder can be linked with the decreased circulation of blood following coronary bypass surgery, abdominal surgery, instances of blood loss through urine and stools due to abdominal trauma, and uric acid nephropathy. Drinking copious amounts of water can help someone to excrete toxins and chemicals from the body. Discontinuation of medicines that may cause obstructions in the kidneys can help in the prevention too.
For the treatment of the failure of the kidneys, diuretics are the class of medicines that help in increasing the urine flow for toxin extraction. Haemodialysis and peritoneal dialysis are the most effective treatments; they help in extracting the toxins and excess water from the body of the affected person; however, it is a short-term treatment. In the long run; however, kidney transplant of at least one kidney can help the patient get back to normal.
FAQs on Renal Failure Explained: Symptoms, Causes, and Treatments
1. What exactly is renal failure, and what happens in the body when it occurs?
Renal failure, also known as kidney failure, is a medical condition where the kidneys lose their ability to adequately filter waste products from the blood. When this happens, harmful levels of waste, such as urea and excess salts, accumulate in the body, leading to a toxic condition called uremia. This can also disrupt the balance of fluids and electrolytes, affecting overall health.
2. What is the main difference between acute and chronic renal failure?
The primary difference lies in the onset and potential for recovery.
- Acute Renal Failure (ARF) is characterised by a sudden and rapid loss of kidney function, often due to an injury, infection, or obstruction. In many cases, ARF can be reversed if the underlying cause is treated promptly.
- Chronic Renal Failure (CRF) involves a gradual and progressive loss of kidney function over months or years. This damage is typically irreversible and is often caused by long-term diseases like diabetes or hypertension.
3. What are the common causes of kidney failure that a student should know as per the CBSE syllabus?
According to the CBSE Biology syllabus, the primary causes of renal failure include:
- Diabetes Mellitus: High blood sugar levels can damage the filtering units of the kidneys over time.
- Hypertension: High blood pressure can damage the blood vessels in and around the kidneys.
- Glomerulonephritis: This is the inflammation of the glomeruli (the tiny filters in the kidneys).
- Obstructions: Blockages in the urinary tract, such as from kidney stones or an enlarged prostate, can also lead to kidney damage.
4. What are some of the early warning signs and symptoms of developing renal failure?
Early-stage kidney disease can be subtle, but key symptoms to be aware of include: decreased urine output, swelling (edema) in the legs, ankles, or feet due to fluid retention, persistent fatigue and weakness, nausea, and shortness of breath.
5. Why is a condition called 'uremia' a direct consequence of renal failure?
Uremia is a direct consequence because the fundamental role of the kidneys is to filter nitrogenous waste, primarily urea, from the blood and excrete it in urine. In renal failure, this filtering mechanism is compromised. As a result, urea and other metabolic wastes accumulate to toxic concentrations in the bloodstream, leading to uremia, which can affect nearly every system in the body.
6. How does the process of haemodialysis work as an artificial solution for renal failure?
Haemodialysis works as an 'artificial kidney' to filter the blood. During the procedure, blood is drawn from an artery and passed through a dialyzer. Inside the dialyzer, the blood flows through tubes made of a semi-permeable membrane (cellophane), which are bathed in a special fluid called dialysate. Waste products diffuse from the blood into the dialysate, while essential substances are retained. The purified blood is then returned to the body through a vein.
7. Can chronic renal failure be completely cured, or can it only be managed?
Chronic renal failure (CRF) is generally considered an irreversible condition and cannot be cured. Medical treatments focus on managing the symptoms and slowing down the progression of the disease. The two main management strategies are dialysis to artificially filter the blood and, ultimately, a kidney transplant, which is the most effective long-term solution for restoring kidney function.
8. What is a kidney transplant and why is it considered the ultimate treatment for renal failure?
A kidney transplant is a surgical procedure to place a healthy kidney from a living or deceased donor into a person whose kidneys have failed. It is considered the ultimate treatment for end-stage renal disease because, unlike dialysis which only performs the filtration function, a transplanted kidney can restore all the vital functions of a healthy kidney, such as regulating blood pressure and producing hormones. A close tissue match is essential to prevent immune rejection.
9. How can managing conditions like diabetes and hypertension help prevent kidney failure?
Managing diabetes and hypertension is critical for preventing kidney failure because they are the two leading causes. Uncontrolled high blood sugar (diabetes) and high blood pressure (hypertension) directly damage the delicate blood vessels and filtering units (glomeruli) within the kidneys over many years. By keeping blood sugar and blood pressure within a target range through medication, diet, and exercise, the long-term stress on the kidneys is significantly reduced, preserving their function.
