What is glomerular filtration or glomerular filtration rate and what is it for?

When we perform a routine blood test we can find different elements that are analyzed or studied in a basic way, mainly because they are indicative of how we are in health and, in some elements in particular, help the doctor to know if the operation of certain organs of the person is the most appropriate.

So, for example, transaminases they can help to discover how the liver is and if it is functioning correctly, or if on the contrary there could be some pathologies or diseases that are preventing its proper functioning (for example, in case of fatty liver or inflammation of the liver).

However, routinely we can also find an element that is studied in a basic blood test: high creatinine. It is a very useful index to know the state of renal function, becoming the simplest, easiest and simplest way to monitor and analyze if the kidneys are performing their function correctly. That is, it is a common indicator that informs the doctor about the kidney function of the person.

However, there are also other elements that are analyzed when the specialist doctor observes or believes that there are signs or signs that the kidneys are not functioning properly, or when a person has already been diagnosed with kidney disease and how this is analyzed. It has been progressing. This is the case of the one known as glomerular filtration ( FG).

What is the glomerular filtration?

It consists of an analysis that serves to measure how the kidneys are filtering the creatinine, a waste substance produced by our muscles, which our body tends to produce at a constant rate. Since the kidneys are the organs in charge of their filtration, excreting it through the urine, When the kidneys are not functioning properly, creatinine tends to accumulate in the blood.

That is, it helps to obtain an estimate of the amount of blood that passes through the glomeruli, which are the tiny filters of the kidneys. Hence, it is essential to verify how these organs are functioning.

It is an analysis that is also known by the names of glomerular filtration rate, Estimated glomerular filtration rate or Estimated TFG.

What is the purpose of the glomerular filtration analysis?

As indicated above, this analysis is useful to measure how the kidneys are filtering the creatinine, since when the kidneys are not functioning as they should, it accumulates in the blood, giving values ​​of high creatinine, that is, above what is considered normal. In this regard we must bear in mind that the values ​​of creatinine They vary depending on the sex and age of the person, so it is not the same level considered as normal for an adult man than for a woman or for a child.

According to National Kidney Foundation, the Normal glomerular filtration results range from 90 to 120 mL / min., although this rate tends to decrease with age so that older people will have GFR levels below what is considered normal.

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  • Candela-Toha Á, Pardo MC, Pérez T, Muriel A, Zamora J. Estimated glomerular filtration rate is an early biomarker of cardiac surgery-associated acute kidney injury. Nephrology 2018 April 20. Pii: S0211-6995 (18) 30045-6. doi: 10.1016 / j.nefro.2018.01.002.
  • Jabary NS, Martín D, Muñoz MF, Santos M, Herruzo J, Gordillo R, Bustamante J. Serum creatinine and creatinine clearance for the assessment of renal function in hypertensive patients. Nephrology 2006; 26 (1): 64-73.
This article is published for informational purposes only. It can not and should not replace the consultation with a Physician. We advise you to consult your Trusted Doctor. ThemesBlood test

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