Kidney Disease

Kidney diseases, or nephropathies, are those that affect the structure and function of the kidneys.

According to the location of the pathology, kidney diseases can be classified into:

• Glomerulopathies: Affect the glomeruli, the kidney’s main filtration unit, made up of a network of capillaries.
• Tubulopathies: Diseases of the renal tubules, responsible for returning filtered blood to the body and carrying urine to the ureters.
• Interstitial nephritis: Inflammation of the kidney's interstitial tissues, which are the tissues surrounding the tubules.
• Nephroangiosclerosis: Affects the renal blood vessels.

Based on the manifestations of kidney diseases, these can be grouped into different syndromes:

• Nephrolithiasis: Presence of kidney stones.
• Nephrotic syndrome: Excessive protein in the urine.
• Nephritic syndrome: Clinical manifestations caused by an inflammatory process in the glomerulus, leading to reduced glomerular filtration, with the main sign being the appearance of blood in the urine.
• Hypertension: Narrowing of the renal arteries, which hinders blood flow.
• Acute renal failure: Sudden deterioration of kidney function.
• Chronic kidney disease or chronic renal failure: Progressive loss of kidney function.
• Tubulopathies: Diseases in which there is a specific tubular dysfunction.
• Urinary infections: Bacterial, viral, or fungal infections of the urinary tract.
• Urinary obstructions: Blockages of urine flow.

Symptoms

Each nephropathy has its own symptoms, but there are common signs in most of the most common kidney diseases:

• Increased or decreased urination.
• Changes in the quantity and appearance of urine.
• Presence of blood in the urine.
• Pain when urinating.
• Lower back pain.
• Swelling in the legs.
• Fatigue.
• Nausea or vomiting.
• Loss of appetite.
• General malaise.
• Headaches.
• Insomnia.

Causes

Each of the syndromes that encompass kidney diseases has different causes:

• Nephrolithiasis: Kidney stones form due to the crystallization of excess salts and minerals. This excess can be due to certain foods or medications, metabolic disorders, or urinary tract infections.
• Nephritic syndrome: Caused by the acute inflammation of the glomeruli (glomerulonephritis) resulting from an immune response to an infection.
• Nephrotic syndrome: Resulting from damage to the glomeruli caused by various kidney conditions that lead to inflammation or scarring of the glomeruli or thickening of their membranes. It is also associated with other diseases such as lupus or amyloidosis.
• Hypertension: Arterial narrowing is caused by plaque buildup in the arteries (atherosclerosis).
• Acute renal failure: Acute renal insufficiency is a syndrome secondary to multiple conditions that lead to reduced blood flow, direct kidney damage, or obstruction in the urinary tract that prevents urine elimination.
• Chronic kidney disease: Caused by an underlying condition that progressively affects kidney function, commonly diabetes (diabetic nephropathy), renal hypertension, and glomerulopathies.
• Tubulopathies: These are often hereditary but can also result from other diseases or the use of medications and toxins.
• Urinary infections: Most are caused by bacteria from the gastrointestinal tract flora, though infections from sexually transmitted diseases are also common.
• Urinary obstructions: Blockages in the urinary tract can be due to congenital malformations, ureter inflammation, clots, tumors, kidney stones, or formation of fibrous or scar tissue.

Risk Factors

The risk of developing kidney disease increases in the following cases:

• Diabetes.
• Hypertension.
• Family history.
• Obesity: Overweight is a risk factor for diabetes and hypertension.
• Smoking: Contributes to hypertension.
• Age: The risk increases after the age of 60.

Complications

Kidney disease can lead to the following complications:

• Irreversible kidney damage requiring dialysis or a transplant to survive.
• Pulmonary edema due to fluid retention in the lungs.
• Affected heart function due to elevated potassium levels or inflammation of the pericardium.
• Alterations in the central nervous system with neurological consequences.
• Anemia, as red blood cell production can be reduced.
• Worsening of the immune response.
• Risk to pregnancy and fetal development.

Prevention

Recommendations to protect kidney health include:

• Control blood sugar, cholesterol, and triglyceride levels.
• Follow a healthy, balanced diet, avoiding salts, fats, and sugars.
• Regular physical exercise.
• Maintain a healthy weight.
• Avoid tobacco and alcohol.

Which doctor treats kidney disease?

Kidney diseases are treated by nephrologists, and some of these conditions may also be monitored by family medicine specialists. In many cases, they are diagnosed in the check-up unit.