What Is Kidney Disease?

Kidney disease is any condition or disorder that affects the proper functioning of the kidneys. It refers to any unhealthy condition or specific illness that affects the kidneys and impairs kidney function. This could range from mild kidney infection to life threatening conditions, such as kidney cancer.

Signs of early kidney problems are not always obvious and can be easily overlooked or ignored. For example, high blood pressure, which is a leading cause of kidney failure, produces very little early warning signs.

Many people who suffer with this condition have no obvious symptoms and may have no clue of its presence or the silent destruction it is causing. If it goes undetected and untreated for an extended period of time, the consequences can be quite devastating to the kidneys and other organs in the body.

Some diseases are hereditary and are passed on from parents to children. These are sometimes unavoidable and can be very difficult to treat. Others are caused by bacteria that either originate in the body or enter the body from external sources and attack the kidneys and other organs.

By far, however, the vast majority of diseases that cause kidney problems result from improper dietary and harmful lifestyle choices. These are sometimes referred to as lifestyle diseases. In many cases, these can be completely reversed by making timely dietary and lifestyle changes.

Occasionally, one or both kidneys may cease to function properly as a result of factors external to the body, such as severe shock caused by trauma.

Whenever the kidneys are affected by diseases (such as high blood pressure or diabetes), normal kidney function becomes impaired. In other words, they are not able to do their job as well as they should. The specific disease or condition that impairs kidney function is referred to as kidney disease, while the actual decline in kidney function is described as kidney failure.

Diseases that cause kidney function to decline over an extended period of time (3 or more months), are described as chronic. There are five (5) stages of chronic kidney diseases. Stage 1 is the least severe while stage 5 represents the most severe. This final stage is also known as end stage renal disease (ESRD). This classification system provides a standard, which offers guidelines for clinical treatment.

Conditions or disorders that result in sudden and rapid decline in kidney function are described as acute.

Common Causes of Kidney Diseases

Renal problems can be caused by a range of factors. Most diseases that affect the kidneys do not necessarily originate in the kidneys themselves, but may result from health conditions in other parts of the body. The following is a list of common causes of kidney disease. (This is not an exhaustive list.)

  • Bacterial infections contribute to diseases of the kidneys. In fact, the most common form of kidney disease, known as pyelonephritis (inflammation of the kidney), is caused by bacterial infection. Such infections tend to originate in the urinary tract (particularly the bladder), then spread to the kidneys. Urinary Tract Infection is a good example of an infection that begins in the urethra or the bladder, but could also affect the kidneys.

    Bacteria that affect other organs can also affect the kidneys. For instance, the bacteria that cause tuberculosis can sometimes travel from the lungs to the kidneys and infect them.

  • Kidney blockage is another factor that can adversely affect the kidneys. It is possible for damaged muscles to release large amounts of protein into the bloodstream, blocking the nephrons. Kidney functions may also be affected by blockage, which is not directly in the kidneys. For instance, an obstruction that affects the flow of urine in the urinary tract can harm the kidneys. Urine stagnation, due to blockage of the urinary tract or prostate enlargement, increases the risk of infection.

    Kidney function can also be affected when the body's immune system is impaired. Antibodies and other substances, which form large particles in the bloodstream, can become trapped in the kidneys' glomeruli, causing inflammation.

  • Diet and lifestyle choices can profoundly impact the health of the kidneys. These are probably the leading causes of kidney disease. Many kidney problems can be avoided or reversed if these two areas are improved.

    While a greater number of people have now become more aware of the consequences of poor diet and lifestyle habits, a lot more still need to be done in order to reduce lifestyle diseases. In many cases, lifestyle diseases such as obesity, high blood pressure and diabetes can be avoided with proper diet, exercise and other healthy lifestyle choices.

    Whatever foods or chemicals we consume or put into our bodies, eventually affect our blood and kidneys (positively or negatively). Since the kidneys are responsible for filtering the blood and maintaining its correct volume and concentration, they are likely to be impacted by components within the blood. So, if we consume more of the correct foods in the right quantities, exercise more often and engage in healthy recreational activities, our kidneys will benefit immensely. If, however, we consume foods or drugs (legal and illegal) that are harmful to our body's biological systems, our kidney functions and general health are likely to decline, leading to diseases.

  • Hypertension (or high blood pressure) is another example of not only a cause but also a symptom of kidney disease. On average, the kidneys receive over 180 liters (50 gal) of blood each day. This means that they take on a heavy work load of balancing the chemicals in the blood and removing waste products. High blood pressure, therefore, puts more stress on the kidneys and eventually damages them.

    Additionally, the kidneys play an important role in helping to regulate blood pressure. Hypertension is therefore an indication that the kidneys are not functioning as well as they should. In this regard, hypertension is both a cause and major symptom of renal problems.

  • Diabetes Mellitus is caused by malfunctioning pancreas that produces little or no insulin, or the inefficient use of insulin by the body. It affects millions of people and is responsible for almost 4 million deaths every year, worldwide.

    Diabetes is sometimes referred to as a lifestyle disease since in many cases, it is completely avoidable. Some simple lifestyle adjustments, such as healthier dietary choices, regular physical activities, maintaining a normal body weight and avoiding tobacco use, can contribute significantly to preventing or delaying the onset of this disease.

  • Kidney stone is another example of a kidney disease that can largely be attributed to poor diet. Tiny stones, sometimes called "silent stones", generally do not cause any problems. They can easily pass undetected trough the ureters (narrow tubes that connects the kidneys to the bladder), into the bladder and eventually out of the body.

    Large stones are quite different and can cause severe kidney problems. They tend to get stuck within the urinary tract, restricting the normal flow of urine. This creates pressure on the kidneys and causes severe pain. Eventually, the pressure created by backed-up urine can cause the kidneys to become swollen, damaged and infected.

  • Kidney cancer is one of the most serious and potentially deadly forms of kidney disease. It causes the cells in certain tissues of the kidneys to grow abnormally and form malignant tumors. These malignant tumors tend to grow quickly and can easily spread to other organs, by way of the blood or lymph. They readily grow into other tissues and replace healthy cells with malignant cells. While the exact cause is not known with certainty, some studies suggest that persons exposed to chemicals such as cigarette tar, nitrites and numerous industrial chemicals are more likely to develop kidney cancer.

  • Birth defects or hereditary disorders in the kidneys may also cause renal problems. Such defects may cause the kidneys to have abnormal shapes or to function improperly.

    Kidney cyst is one example of a kidney condition that is caused by hereditary or genetic disorder. This condition is not usually classified as a disease, since in most cases it does not affect normal kidney function. There is another condition, however, which is similar to kidney cyst but is much more serious. It is called polycystic kidney disease. This is a genetic disorder characterized by the growth of multiple cysts on the kidneys. These cysts can slowly replace much of the kidney tissue, reducing kidney function and ultimately lead to kidney failure.

    Alport Syndrome is another serious hereditary disorder that not only affects the kidneys, but vision and hearing as well. It is more common in males, with much more severe symptoms. Although some women with this condition display little or no symptoms, they can pass it on to their children.

    Kidney reflux disease is a condition also caused by hereditary or genetic disorder. It is found mainly in children who inherited it from their parents. It begins in the bladder and eventually affects the kidneys. With this condition, urine is allowed to flow back up towards the kidneys, which can result in serious kidney damage.

    Medullary sponge kidney is rare kidney disease that causes pools of urine to remain in the kidneys. These pools of urine encourage stone formation and kidney infection. Although some cases of this disorder seem to be inherited, usually the cause is not known.

The causes of kidney disease are numerous. Since the major function of the kidney is to filter and regulate the blood, any disease that affects the blood or that can be transported in the bloodstream can also affect the kidneys. The body is a unit of inter-related systems, therefore, diseases that affect other organs or parts of the body can very easily affect the kidney, and vice versa.

Regulating our diets, exercising regularly and minimizing our exposure to harmful chemicals and substances, can go a long way in helping to prevent kidney disease and other serious medical conditions.