my mom who is 67yrs old suffering from diabetes, hypertension, high cholesterol has been diagnosed with right kidney functioning at 24% (the kidney has shrunk in size) and the other kidney is functioning at 76%. I am worried.
Has your mother had continuing kidney problems? Did she have previous scans of her kidneys?
Sometimes we are born with one kidney that is much smaller than the other, and eventually that kidney will shrink up to nearly nothing. As long as the other kidney is functioning well, there's nothing to worry about. If her total kidney function is at 76% or greater, given her age and her other health problems, she's doing pretty well as far as kidney function goes. That said, it is vitally important that her blood pressure be tightly controlled, as well as making sure her diabetes is under good control. Those two things will help prevent any further impairment to her overall kidney function.
I agree with Ruth. It sounds like her total function is still close to 100% with one kidney bearing more of the load. Another thing you might want to do is cut back on sodium (especially in prepared foods).