Creatinine
Creatinine is a waste product that comes from the normal wear and tear on muscles of the body. Everyone has creatinine in their bloodstream. Its value is dependent on Age, Race and Gender of the patient and the general reference range is 0.4-1.4mg/dl.
It is just one of the many toxins rising from Kidney failure, there are thousands of such molecules which are not measured or cannot be measured. Creatinine hence is a surrogate for all the other toxins of renal failure and by itself may not be the sole determinent of symptoms, however it acts as a general guide or reference to the things happening internally.
When kidneys function normally, creatinine is filtered off the blood through the kidneys.
When creatinine levels are high, it can be an indicator of kidney disease.
To find out a person’s creatinine levels are, doctor will order a blood test called serum creatinine to determine kidney function and use the number to calculate the glomerular filtration rate (GFR), which can determine the stage of kidney disease.
Doctors perform two other tests to determine creatinine level -creatinine clearance (Ccr or CrCl) and/or GFR, which measures how much of the function is affected, or how well kidneys filter waste.
When a person has kidney disease, his or her doctor will continue performing creatinine test at regular intervals to monitor the disease progression and to determine treatment.