In medical terms, GFR abbreviates to Glomerular Filtration Rate. GFR is basically the measurement of the Kidney Function. It is used in the assessment of Kidney health and determine whether the kidneys are functioning as they are supposed to function. The kidney is an organ that helps in the purification of blood. The human body consists of a pair of them. Kidneys help in balancing the fluid in the body, they check on the right amount of electrolytes, along with blood purification. Once the blood is filtered, the purified blood goes back to the body and the waste is removed in the form of urine. Glomeruli are the tiny capillaries that lie within the nephrons of kidneys which play an important role in the filtration process.
The Glomerular Filtration Rate( GFR ) cannot be measured directly hence before that, measurement of creatinine and creatinine clearance is considered.
Creatinine is a residual product which is produced after the breakdown of muscles, this is excreted through urine after the blood undergoes filtration by kidneys. Creatinine clearance means the total volume of blood that is purified of creatinine by the kidneys. Creatinine clearance is a potent method for measurement of the renal function. The creatinine clearance differs based on the gender, age, height, and weight of the individual.
Firstly blood sample is collected to check the creatinine levels in the blood. For a creatinine clearance test, urine is collected and stored for 24 hours and then brought for testing. The more the creatinine level in the blood, the lower is the creatinine clearance and GFR.
Before the test is conducted the patient must inform the physician whether they are on any kind of medication or they have any problem since there are certain diseases like diabetes, thyroid dysfunction, hypertension, or certain antibiotics that might cause alteration in the test result.
Determining chronic kidney disease using GFR:
The normal GFR range varies between 90-110mL/min/1.73m2 . GFR decreases with age hence in older people the GFR would be lower than normal.
A physician generally classifies the kidney disease based on the staging system that uses GFR:
Stage 1: This comes under normal kidney function since the GFR is 90 or more.
Stage 2: There would be a mild variation in the kidney function since the GFR would be around 65-85.
Stage 3: The kidney function is moderately reduced and the GFR is between 35-60.
Stage 4: The kidney function is severely affected and the GFR is between 15-30.
Stage 5: The GFR is less than 15 and it is considered as kidney failure. In this stage usually, people require dialysis for blood purification.
If the GFR is more than 120 then it is considered as Hyperfilteration which usually happens in the elderly.
Managing Kidney Disease:
Kidney disease is mainly caused in the case of long term Diabetes or Hypertension. When an individual is detected with either of these problems the first line of treatment includes lifestyle modification by improving the eating habits, exercising, and keeping the metabolism fit. The initial stages of kidney diseases can be managed with this along with some medications. However, where severe kidney disease is involved the patient must be monitored very carefully and hospitalization becomes necessary.
If the patient is neither Diabetic nor Hypertensive then evaluation is done subjecting the patient to other tests and examinations to determine the root cause.
Even a healthy individual is subjected to GFR or Creatinine Clearance tests to make sure the Kidneys are working fine and to properly prescribe the medications in case any decline in the kidney function is noted.
Generally, in a normal individual, the decline in the kidney function takes place due to few analgesics so it is always recommended not to take any over the counter medication until prescribed by a physician.
1. Is creatinine clearance and GFR the same?
The creatinine clearance is an estimate of GFR( Glomerular Filteration Rate ). However, the Creatinine Clearance can be slightly higher than the actual GFR since Creatinine is secreted by proximal tubule in addition to the filtering by Glomerulus.
2. What does it mean to have a low GFR?
The measurement of GFR helps the medical professional to assess the stage of the kidney disease. If the GFR is low then it indicates that the Kidneys are not working as they should. The earlier a kidney disease is identified the sooner the damage can be controlled by proper medication.