The human body has two kidneys about 115 g in size located at the back of the peritoneal cavity, which are its vital organs.

The main function of the kidneys is to regulate the balance of salt, water and other ions and trace elements in the human body, such as calcium, phosphorus, magnesium, potassium, chlorine and various acids.

At the same time, the kidneys secrete hormones such as erythropoietin, vitamin D and renin. In particular, erythropoietin stimulates the production and maturation of red blood cells in the bone marrow, while vitamin D regulates the body’s calcium and phosphorus, bone structure and a host of other actions. The kidneys are also the site of action of hormones responsible for regulating blood pressure, fluid balance or bone metabolism and vascular calcification.

Finally, the kidneys eliminate all the waste products of metabolism as well as drugs and other toxins that enter the body.

The decline in kidney function is called chronic kidney disease (CKD). By this definition we mean a decline in kidney function to varying degrees for a period of more than three months.

There may also be no decrease in kidney function but there may be a functional disorder, such as protein excretion (albuminuria) or microscopic haematuria, or on the other hand there may be a structural disorder as determined by imaging (kidney ultrasound).

How is kidney disease documented?

The diagnosis of kidney disease is made, in addition to the measurement of leucoma excreted in the urine, the detection of microscopic haematuria or the imaging tests mentioned above, by assessing renal function through the calculation of the Glomerular Filtration Rate (GFR). This calculation takes into account the patient’s body measurements, age, sex, race and laboratory values of serum creatinine. On the basis of the GFR, CKD is classified into five stages.

In some cases, a percutaneous kidney biopsy is performed to determine the specific type of kidney disease, the extent of kidney involvement and to plan specific treatment.

Symptoms of kidney disease

A peculiarity of chronic kidney disease is the fact that it often runs its course without symptoms or, if present, they are blunt.

Symptoms appear when kidney function is reduced to 15-20% of normal and may manifest as weakness, easy fatigue, sensitivity to cold, swelling in the lower limbs, itching, “foamy” urine due to increased excretion of albumin, hematuria.

It is also possible for patients with CKD to develop life-threatening conditions due to hyperkalemia, metabolic acidosis or pulmonary oedema.

Among the complications of renal failure are :

  • anemia
  • skin pigmentation
  • nausea
  • vomiting
  • anorexia
  • bone disease
  • libido disorders
  • impotence
  • inactivity
  • convulsions
  • peripheral neuropathy
  • myopathy
  • uremic coma
  • arterial hypertension
  • pericardial effusion
  • sleep disorders
  • restless limbs
  • muscle cramps 
  • susceptibility to infections.

The earlier the diagnosis of kidney disease is made, the greater the chance of avoiding serious and life-threatening complications.

Causes of chronic kidney disease

The most common causes of CHD, which account for two-thirds of cases, are diabetes mellitus and hypertension.At the same time, chronic kidney disease itself can cause high blood pressure.

Other conditions that can cause kidney damage are:

  • glomerulonephritis
  • hereditary diseases
  • congenital malformations of the fetus
  • lupus and other autoimmune diseases
  • obstructive nephropathy  caused by problems such as kidney stones
  • benign and malignant tumors or prostate gland hypertrophy in men
  • urinary tract infections
  • drug toxicity

If for some reason the kidneys are underactive, many drugs are not normally eliminated from the body, causing them to accumulate in the blood and create toxic effects. Also, many drugs affect the function of the kidneys themselves.

The most common nephrotoxic drugs are non-steroidal anti-inflammatory drugs, which are used in musculoskeletal pain.

Other nephrotoxic drugs are various antibiotics, such as aminoglycosides.

Drugs used in imaging tests (CT scans, pyelography, coronary angiography, etc.) are called iodinated contrast agents and may have a nephrotoxic effect.Immunosuppressive drugs such as cyclosporine and methotrexate damage the kidneys in chronic use, as do antineoplastic drugs (such as cis-platinum).Finally, several other substances (snake venoms, mushrooms, herbicides, some herbs and heavy metals such as lead and mercury) also cause nephrotoxic damage.

Treatment of Chronic Kidney Disease

The first step in treating CKD is to prevent kidney disease. This includes identifying the predisposing factors (age, family history, race, kidney size) and the initiating factors of kidney disease (diabetes, hypertension, infections, autoimmune diseases, lithiasis, medications). This is followed by the treatment of CKD, which involves:
  • slowing the progression of kidney disease by controlling albuminuria
  • arterial hypertension
  • smoking cessation
  • improving lipid profile
  • and controlling diabetes.
At the same time, specific causes that may be reversible are identified and corrected. Finally, the treatment of the complications of progressively worsening kidney disease is essential. Among other important aspects are
  • the management of renal anemia
  • the treatment of bone disease and metabolic acidosis, together with appropriate dietary guidelines
  • evaluation of medication and preparation in advanced stages for renal function replacement therapy.

Kidney Failure

Despite all of the above, the patient is likely to end up in the end stage of Chronic Kidney Disease which means that he or she has lost more than 85% of normal kidney function. In contrast to what happens with other organ failure, the patient has options to replace renal function while maintaining a satisfactory quality of life. Substitution of kidney function Hemodialysis: The patient undergoes treatment to clear his blood of metabolic waste products through a special hemodialysis machine, usually three times a week. Depending on the patient and his or her co-morbidity, it is possible to modify the mode and duration of hemodialysis. Peritoneal dialysis:
The patient is treated to clear the metabolic waste substances through special solutions that enter the peritoneal cavity daily. Kidney transplant:
This is the substitution method that is ideal for each patient, instead of hemodialysis or peritoneal dialysis, and is performed in special Transplant Centers. The kidney transplant can be from a living or cadaveric donor. The advantage is that the patient can have an excellent quality of life. At the same time, however, continuous administration of immunosuppressive drugs is necessary in order to prevent the kidney transplant from being rejected by the body, which recognizes it as a foreign body. For this reason and to avoid infections or other complications from the treatment, regular nephrological monitoring is required.