Brief answer....given below Detailed answer.... Hello, Thanks for the query. eGFR is a test which assesses how well and properly your kidneys are functioning. ...The eGFR (estimated glomerular filtration rate) is a number based on your blood test for creatinine,age and sex. Creatinine is a breakdown product of muscle and is normally cleared by the kidneys.If your kidneys are not working or functionally working,then it's level in the blood increases. ...eGFR is a calculation based on blood tests and not necessarily a true reflection of your kidney functions. ...The eGFR is a good test, but it’s not for everyone.  this test may not be accurate if you are younger than 18, pregnant, very overweight or very muscular,malnourished,people who have had amputation of one arm or leg,people with water retention etc. ....not all clinicians agree with the classification which states the normal kidney function means eGFR above 90,because this way many elderly people with no kidney disease or mildly reduced kidney functions,would be labelled as CKD patients. ...the fact which is generally recognised is that eGFR above 60 is considered as normal. ...if a person has normal blood pressure,no diabetes,no abnormal urine report or no abnormal creatinine,then this value of 51 can be taken as normal,however it will not be proper and prudent on my part to comment on it any further,since you have not stated your kidney function test reports and urine analysis report. Please state your reports,so that we can go ahead with our discussion. There is no doubt that this value of 51 does raise doubts and need clarity and clarification,because according to the table,it can be classified as stage 2 kidney disease. I hope it helps,however you may revert to me for any further clarification. Thanks

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