The kidneys are responsible for numerous physiological functions. They filter your blood from toxic substances, regulate your blood pressure, and even produce a hormone which controls the production of red blood cells (erythrocytes). Kidney failure can have different causes, such as cardiovascular disease, bacterial and viral infections, autoimmune diseases, etc. However, the first symptoms are usually similar in all those cases. If you notice any of the following symptoms, you are advised to visit your doctor and perform some routine tests of kidney function.
- Less Frequent Urination
In persons with kidney failure, the kidneys usually produce lower amount of urine than it is normal. This is because the damaged kidneys are not able to filter as much blood as normal kidneys. Lower frequency of urination can be symptomatic of kidney disease and requires detailed examination. The necessary amount of daily urine, below which the human organism cannot function is 500 ml, regardless of the amount of fluid you take during the day.
As a consequence of inappropriate elimination of excess water and sodium from the circulation, swelling of the soft tissues can also appear in persons with damaged kidney function. The swelling is usually present around the ankles and feet and it is usually worse during the day than during the night.
- Pain in The Kidney Area
If you feel chronic pain or even discomfort in the middle-to-lower back, it can be a sign of kidney disease. Bacterial infections of the kidneys can cause glomerulonephritis and usually produce this symptom. They can be treated successfully by antibiotics, but it is important to discover them before they make serious damage to the kidneys.
- Heart Palpitations and Muscle Cramps
The kidneys are also responsible to keep optimal balance between minerals and electrolytes in bodily fluids. Damaged kidneys lose the ability to keep potassium and calcium in the body, which can affect muscle contraction. The heart can suffer from arrhythmia due to lack of potassium, and skeletal muscles can experience cramps and twitching due to electrolyte imbalance.
Accumulation of the unnecessary and harmful substances, which should have been eliminated by the kidneys, can produce the feeling of fatigue, exhaustion, insomnia, nervousness, and even mental problems.
Hypertension (high blood pressure) is one of the most common symptoms of kidney disease. The damaged kidneys are not able to eliminate enough fluid from the body, so it remains in the circulation and applies pressure on the walls of the blood vessels. Hypertension due to kidney disease belongs to so called secondary hypertensions, which account for about 5% of all patients with high blood pressure. This type of hypertension caused by kidney failure is usually hard to treat.
Anemia usually occurs in advanced stage of kidney failure, due to the inability of the kidneys to produce erythropoietin, the hormone which stimulates the production of red blood cells. The symptoms include exhaustion, tiredness, pale skin, fragile nail plates, dry skin, and sometimes syncope (short episodes of fainting). This anemia can be treated by erythropoietin injections.
Electrolyte imbalance combined with accumulation of toxic metabolic products can sometimes trigger seizures in patients with kidney disease. The human brain is very vulnerable and highly sensitive to many toxic substances. That is why sometimes it can react in unpredictable ways. Patients with kidney disease can sometimes express abnormal behavior, hallucinations, and signs of delirium or mental illnesses.
- Uremic Coma
Uremic coma appears when the concentration of toxic substances containing nitrogen is so high that they prevent normal functioning of the nervous system. This is an emergency situation and it requires immediate life support measures and hemodialysis.
- Increased Blood Levels of Urea and Creatinine
Urea and creatinine are normal products of metabolism and the kidneys are responsible for their elimination. By measuring levels of these substances in the blood, we can actually assume to what extent the kidney damage has progressed. Creatinine level measurements can also be used to assess the efficacy of the kidney disease treatment.
Of course, not all the persons with kidney problems will have all of these symptoms, but catching some of them in the early stage can be very helpful for discovering the cause of kidney damage and stop further worsening of the disease.
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