This substance is produced by the muscles and eliminated by the kidneys, so high levels mean that the body may not be able to eliminate it properly, indicating possible problems in the organs.

The normal reference values for creatinine levels in the blood are between 0.5 to 1.1 mg/dL for women and 0.6 to 1.2 mg/dL for men. But, according to Eugênia Maria Amôedo Amaral, BenCorp's medical manager, since the substance is produced in the body according to the degree of muscle mass, it is normal for men to have higher levels of creatinine in the blood, because theygenerally have more developed muscles than women.

"Normal blood creatinine values can vary by laboratory, and are different between men and women, so it is considered that creatinine is increased in men when the concentration is greater than 1.2 mg/ dL and in women when it is greater than 1.0 mg/ dL," he explains.

High Creatinine: Symptoms

When creatinine levels in the blood are much higher than normal, some of these symptoms may arise:

• Excessive fatigue
• Nausea and vomiting
• Feeling of shortness of breath
• Swelling in the legs and arms
• Weakness
• Fluid retention
• Mental Confusion
• Dehydration
• Finally, dry skin

Other causes

The increase of creatinine in the blood usually indicates problems in the kidneys, since the substance is filtered by them, but this doesn't happen in all cases. So, according to Eugenia, there are other important causes:

• Excessive physical activity (case of athletes and bodybuilders) This practice can increase the creatinine level in the blood due to the amount of muscle mass of these people. Other than that, it is common to supplement the substance in order to gain muscle, increasing the rates. In this case, there is no indication of alteration in the kidneys.
• Pre-eclampsia: occurs when there is a rise in blood pressure and a decrease in blood circulation during pregnancy, so it is a serious condition in which kidney damage is possible, and creatine accumulates in the blood.
• Infection or renal failure: In other words, kidney infection is caused by bacteria present in the urinary system, while renal failure is characterized by changes in kidney function, with reduced filtering capacity in the blood. This can be caused by a number of factors, from overuse of protein supplements andmedications to dehydration.
• Diabetes: When the disease is uncontrolled, there can be higher levels of glucose in the blood and complications such as changes in the kidneys.

How to know if creatinine is high?

The doctor warns that one should seek a doctor whenever the creatinine results are altered. Thus, some tests can help in the identification of the problem and its causes, such as partial urine creatinine and microalbuminuria, blood and urea tests, creatine clearance, kidney and urinary tract ultrasound and others that may be ordered by a nephrologist. In addition, if there is an increaseof creatinine in the urine, depending on the related reason, the treatment may involve diuretic, antibiotic, or even hypertensive medications.

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