urinary tract health

Kidney failure

Generality

Kidney failure is the medical term that indicates an inability on the part of the kidneys to properly perform its functions (clean up blood from waste products, regulate the hydro-saline and acid-base balance of blood, produce erythropoietin, etc.).

Those suffering from kidney failure suffer from a serious health condition, worthy of adequate and timely care.

There are two types of renal failure: acute renal failure and chronic renal failure.

The first is reversible, while the second has irreversible effects.

The causes of kidney failure are numerous and require careful diagnosis for their correct identification.

Treatment depends on the type of renal failure. In general, both the acute form and the chronic form include: a causal therapy, a symptomatic therapy, dialysis and the adoption of a particular lifestyle.

Short revision of the kidneys

Two in number, the kidneys are the main organs of the urinary or excretory apparatus.

The excretory apparatus is the set of anatomical organs and structures responsible for the production and elimination of urine .

Returning to the kidneys, these reside in the abdominal cavity, on the sides of the last thoracic vertebrae and the first lumbar vertebrae; they are symmetrical and have a shape that is very reminiscent of a bean.

The most important functions of the kidneys are:

  • Filter waste substances, harmful substances and foreign substances present in the blood and convert them into urine.
  • Adjust the hydro-saline balance of blood.
  • Adjust the acid-base balance of blood.
  • Produce erythropoietin glycoprotein.

The blood on which the kidneys act comes from the renal artery and returns to the venous system through the renal vein; renal vein which then rejoins the vena cava.

The anatomy of the kidneys is quite complex: the image below shows the main anatomical elements of a generic human kidney.

What is kidney failure?

Kidney failure is a serious medical condition, the presence of which is indicative of an inability on the part of the kidneys to properly perform its functions.

WHAT HAPPENS WHEN KIDNEYS WORK EVIL?

When the kidneys malfunction, various mechanisms are skipped:

  • The mechanism of disposal of waste substances present at the blood level. This involves the progressive accumulation of these substances and the consequent intoxication of the blood.

    Two important parameters that describe the amount of waste substances accumulating in the blood are azotemia and creatininemia .

    Azotemia is the concentration of non-protein nitrogen (or urea) in the blood; non-protein nitrogen is a waste product of protein metabolism.

    Creatininemia, on the other hand, is the concentration of creatinine in the blood; creatinine is a waste product deriving from the metabolism of creatine in the muscles.

    A high azotemia and, in the same way, an elevated creatininemia are indexes of a malfunction of the kidneys.

  • The mechanism of regulation of the hydro-saline balance of blood. This involves the accumulation of fluids (edema) in various parts of the body, for example in the legs or ankles.
  • The mechanism of regulation of the acid-base balance of blood. From this derives an alteration of the blood levels of electrolytes, such as phosphorus and potassium.
  • The production mechanism of erythropoietin.

Types

Doctors and experts in renal diseases distinguish two types of renal insufficiency: acute renal failure and chronic renal failure .

The criterion of distinction is the speed with which the kidneys lose their functional capacity.

In acute renal failure, the kidneys lose their functions suddenly and abruptly. The term "acute" refers precisely to the suddenness with which the medical condition is established.

In chronic kidney failure, however, the kidneys lose their functional capacity gradually, gradually. Loss of kidney function is an inexorable and slowly evolving mechanism, which can last months or even years.

While in the case of acute renal failure it is possible to restore renal functions (therefore the condition is potentially reversible), in the case of chronic renal failure the recovery by the kidneys of their functional capacity is normally impossible.

As you will see, for both conditions, there are treatments, but their purpose is different.

Causes

The causes of kidney failure are numerous and represent a very broad topic.

Therefore, for reasons of clarity, this article will treat the triggers of acute renal failure and the factors triggering chronic renal failure.

CAUSES OF ACUTE RENAL FAILURE

Acute kidney failure can occur in the presence of:

  • Conditions that slow or block direct blood flow to the kidneys.

    These conditions include:

    • Myocardial infarction (or heart attack);
    • Heart diseases ;
    • Liver failure . It is a serious medical condition, the establishment of which implies the incapacity of the liver to correctly fulfill its functions;
    • Inadequate intake of aspirin, ibuprofen, naproxen and other similar drugs;
    • Allergic reactions ;
    • Severe burns ;
    • Severe dehydration ;
    • Severe bleeding ;
    • Inadequate intake of blood pressure reduction drugs (hypotensive drugs).

  • Conditions or events that cause direct damage to the kidneys. These conditions include:
    • The formation of blood clots in the arteries or veins of renal blood vessels;
    • The formation of cholesterol deposits in renal blood vessels. This obstructs the flow of blood through the kidneys;
    • Glomerulonephritis, or inflammation of the renal glomeruli (see the figure on the anatomy of a kidney);
    • The so - called hemolytic-uremic syndrome . It is a disease of the blood and kidneys. In addition to causing acute renal failure, this condition also causes microangiopathic hemolytic anemia and thrombocytopenia;
    • Infections of the kidneys;
    • Systemic lupus erythematosus . It is an autoimmune disease that can cause glomerulonephritis;
    • The use of pharmacological or medical substances, such as chemotherapy, antibiotics, contrast fluids for diagnostic imaging tests and zoledronic acid;
    • Multiple myeloma ;
    • Scleroderma, a disease of the skin and connective tissues, which also damages renal blood vessels;
    • Thrombotic thrombocytopenic purpura, a very rare blood disorder;
    • Intoxications from alcohol, cocaine or heavy metals ;
    • Vasculitis, or inflammation of the blood vessels.

  • Conditions that block the flow of urine into the organs and structures of the excretory system. These conditions include:
    • Bladder cancer ;
    • The formation of blood clots in the urinary tract ;
    • Uterine cervical cancer, in women;
    • Colon cancer ;
    • Benign prostatic hypertrophy, in humans;
    • Kidney stones ;
    • Prostate cancer, in humans;
    • Damage to the nerve structures that control the bladder.

NB: it should be pointed out that many of the conditions affecting the flow of urine along the excretory apparatus are also the cause of chronic renal failure.

CAUSES OF CHRONIC RENAL FAILURE

The main conditions or diseases that can cause chronic kidney failure are:

  • Type 1 diabetes and type 2 diabetes ;
  • Hypertension ;
  • Glomerulonephritis ;
  • Interstitial nephritis, an inflammation of the renal tubules and surrounding structures (to identify the renal tubules, see the figure relating to the anatomy of a kidney);
  • The polycystic kidney ;
  • Prolonged obstruction in the urinary tract. The causes of obstruction include: benign prostatic hypertrophy, kidney stones and some neoplasms in the organs adjacent to the structures that make up the urinary tract;
  • Vesicoureteral reflux . It is a disease characterized by the rise of urine from the bladder to the ureters, first, and the renal pelvis, then;
  • Kidney infections, such as a pyelonephritis (inflammation of the renal pelvis).

RISK FACTORS OF ACUTE RENAL FAILURE

The subjects most at risk of acute renal failure are: the elderly, diabetics, people suffering from hypertension, heart patients, carriers of a kidney disease, individuals with liver disease, people with high cholesterol levels blood and carriers of the so-called peripheral arterial disease.

RISK FACTORS OF CHRONIC KIDNEY FAILURE

The subjects most at risk of chronic renal failure are: diabetics, people suffering from hypertension, heart patients, smokers, individuals with high levels of cholesterol in the blood, the obese, the elderly, people with a history family of kidney diseases, African-American individuals, Native Americans and Asio Americans.

Symptoms and Complications

To learn more: Symptoms of Renal Insufficiency

The symptoms and signs of renal failure are numerous.

The presence of: high azotemia (or hyperazotemia ) depends on:

  • Vomiting and diarrhea. These two conditions often involve dehydration
  • Nausea
  • Weight loss
  • Nocturia (ie need to urinate during the night)
  • Frequent urination, with urine having a light color
  • Reduced urination, with urine having a somewhat dark color
  • Blood in the urine
  • Difficulty urinating

On the accumulation of phosphorus in the blood ( hyperphosphataemia ) depends the presence of:

  • itch
  • Damage to the bones
  • Failure of bone repair, in case of bone fractures
  • Cramps or muscle spasms

The presence of: from the accumulation of potassium in the blood ( hyperkalemia )

  • Muscular paralysis
  • Cardiac rhythm abnormalities

The presence of: from the accumulation of fluids in the various tissues of the human body ( water retention )

  • Swelling in the legs, ankles, feet, hands and face
  • Pleural effusion and / or pericardial effusion, conditions from which dyspnea (or shortness of breath) and chest pain result

A reduced production of red blood cells and a consequent state of anemia depend on the lack of production of erythropoietin . This state of anemia involves:

  • Sense of fatigue, tiredness and weakness
  • Drowsiness
  • Memory problems and confusion
  • Difficulty concentrating
  • Dizziness
  • Hypotension

Finally, due to the failure to carry out other renal mechanisms, the following may appear:

  • Foamy urine
  • Hypertension
  • Loss of appetite
  • Night sleep disorders
  • Darkening of the skin
  • Convulsions

TYPICAL SYMPTOMS OF ACUTE RENAL FAILURE

Typical symptoms and signs of acute renal failure include: reduced urine output, lower limb edema, drowsiness, dyspnea, fatigue, confusion, nausea, convulsions and chest pain.

TYPICAL SYMPTOMS OF CHRONIC RENAL FAILURE

Symptoms and signs of chronic renal failure appear gradually.

The classic clinical manifestations of this medical condition are: nausea, vomiting, loss of appetite, sense of fatigue and weakness, disturbed sleep at night, impaired urine production, reduced mental acuity, spasms and / or muscle cramps, hiccups, edema lower limbs, itchy skin, chest pain, dyspnea and hypertension.

WHEN TO REFER TO THE DOCTOR?

The presence of the aforementioned symptoms and signs must induce an individual to immediately contact his own doctor and consult with him about what to do.

Kidney failure is a medical condition that requires proper treatment. Otherwise, the patient's life is in serious danger.

COMPLICATIONS

Kidney failure is in itself a complication of other conditions or diseases.

Having said this, its further deterioration may coincide with: an aggravation of water retention (a condition of pulmonary edema is established); an even greater risk of bone fractures; the appearance of impotence or reduced libido; damage to the central nervous system, with all the consequences of the case; a reduction in immune defenses (hence a greater susceptibility to infections); for a woman, the impossibility of facing a pregnancy; the need to undergo dialysis or a kidney transplant surgery; finally, death, especially in the absence of adequate or timely treatment.

Diagnosis

For a correct diagnosis of renal failure and its triggering causes, the fundamental tests are: physical examination, medical history, blood tests, urinalysis and some diagnostic imaging tests.

In some situations, the use of a renal biopsy may also be necessary.

OBJECTIVE AND ANAMNESIS EXAMINATION

Physical examination and medical history are two diagnostic evaluations that provide useful information about the symptoms and signs shown by the patient.

Furthermore, they allow the doctor to understand the health status of the person under examination and to get an idea of ​​the possible causes of the symptomatology in progress.

BLOOD ANALYSIS

Blood tests can be used to measure blood concentrations of urea - that is, azotemia - and creatinine concentrations - creatininemia.

Azotemia and creatininemia are two parameters that allow a significant assessment of an individual's renal function.

URINE ANALYSIS

Urinalysis provides information on the causes and characteristics of kidney failure in an individual.

DIAGNOSTICS FOR IMAGES

Among the possible diagnostic imaging tests, the following are worth mentioning: the ultrasound - which allows an evaluation of the anatomy and the size of the kidneys - and the abdominal CT - which provides three-dimensional images of the kidneys rich in details.

RENAL BIOPSY

Renal biopsy is a minimally invasive diagnostic test, which consists in collecting a sample of kidney cells (renal cells) and in its subsequent laboratory analysis.

Renal biopsy involves local anesthesia and the use of a long needle for aspiration of the renal cell sample.

Renal biopsy is useful to clarify the causes of renal failure.

Treatment

Generally, the treatment of renal failure involves a therapy aimed at treating the causes ( causal therapy ), a therapy focused on improving the symptomatic picture and complications ( symptomatic therapy ), dialysis and the adoption of a lifestyle appropriate to the circumstances in place.

Analyzing the two types of renal insufficiency in more detail, it is appropriate to specify three aspects immediately:

  • Acute renal failure usually requires hospitalization of the patient until renal function is resumed. Early discharge is very rare.
  • Chronic kidney failure is also treatable from home and is among the conditions for which kidney transplantation is indicated.
  • The purpose of treatment of acute renal failure is to eliminate the cause of the aforementioned condition and restore normal renal function .

    The purpose, instead, of the treatments of chronic renal failure is to eliminate the triggering cause (s) and slow down, as far as possible, the inexorable progression of the disease .

ACUTE RENAL FAILURE: SYMPTOMATIC THERAPY

Generally, the symptomatic therapy that doctors adopt in case of acute renal failure includes:

  • The use of remedies and drugs to favor the renal elimination of those liquids that have accumulated in the tissues. Among the medicines used, diuretics deserve a mention.
  • The administration of drugs that regulate the concentration of potassium in the blood. Usually, the purpose of these medicines is to prevent the accumulation of potassium in the blood.

    Among the indicated drugs, sodium polystyrene sulfonate is used in particular.

  • The administration of drugs that restore the normal concentration of calcium in the blood. These are calcium infusions .

CHRONIC RENAL FAILURE: SYMPTOMATIC THERAPY

Generally, the symptomatic therapy adopted in case of chronic renal failure includes:

  • The administration of drugs against hypertension. Medicines used for this purpose include: ACE inhibitors, angiotensin II receptor antagonists and diuretics .
  • Medication to lower cholesterol levels. Examples of such medicines are statins .
  • The administration of drugs and other substances against anemia. Generally, against anemia due to chronic renal failure, doctors prescribe erythropoietin and iron supplements.
  • The administration of medicines to reduce the edemas present in the body.
  • Drug administration to protect bones from fractures. Medicines used for this purpose include: calcium and vitamin D supplements and drugs to reduce excess phosphorus in the blood.

DIALYSIS

Briefly, dialysis is a treatment that artificially reproduces certain functions of the kidney, cleaning up the blood from excess waste products and water.

Figure: dialysis

KIDNEY TRANSPLANTATION

Kidney transplantation is a surgical procedure to replace both kidneys with a healthy kidney from a compatible donor.

In general, the "new" kidney belongs to a recently deceased donor; however, there is also the possibility of taking a kidney from a living and consenting subject.

Usually, living donors are direct family members, although they could be volunteers who are completely unrelated to the recipient.

Kidney transplantation is the treatment indicated for the final stages of chronic renal failure.

LIFESTYLE AND HOMEMADE REMEDIES

Generally, every patient with kidney failure receives precise instructions from their treating physician on what type of diet to adopt .

Keeping to the letter of the doctor's planned diet is a fundamental cornerstone of the therapeutic process.

Among the most frequent recommendations regarding the type of diet to be followed in case of renal insufficiency are:

  • Avoid too salty foods.
  • Prefer foods low in potassium.
  • Limit the ingestion of protein-rich foods.
  • Limit foods that are high in phosphorus.

Prognosis

The prognosis in case of renal insufficiency depends on the type, the triggering causes, the timeliness of the diagnosis and treatments and, finally, on the general health conditions of the patient.

Prevention

Avoid or limit the consumption of alcohol, do not exceed the use of drugs that could damage the kidneys (aspirin, ibuprofen, etc.), control body weight, follow a healthy and low-salt diet, do not smoke, exercise regularly with regularity, treating even the least worrying of kidney problems immediately are the main preventive measures against kidney failure.