91原创

Skip to content
Join our Newsletter

Your Good Health: High GFR, creatinine level signify kidney damage

The higher the creatinine level, the worse the kidney function. That, age and sex are used to estimate a person鈥檚 kidney function.
web1_dr-keith-roach-with-bkg
Dr. Keith Roach

Dear Dr. Roach: Last summer, a city policeman came to my door. My doctor had been unable to contact me with results of a recent blood test and called police. The officer handed me a card with the results. My creatinine level was 4.1, and my glomerular filtration rate (GFR) was 14. He said the numbers indicated that my kidneys were failing and that I should go to the emergency room immediately. Except for swelling in one ankle, I had no symptoms.

During a day and a half in hospital, I lost 14 pounds of fluid after the insertion of a catheter. Within two weeks, my creatinine level was at 2.1. After a few months of wearing the catheter, my prostate was “trimmed back” (my words, not the doctor’s) using a procedure called a “TURP.” I am back to normal.

What is a TURP, and how routine is it? Are there long-term negative effects? How close did I come to kidney failure?

T.J.R.

Your problem was obstruction of the urine flow due to an enlarged prostate. The urethra, the tube that carries urine out of the body, goes right through the middle of the prostate, and an enlarged prostate can block flow partially or completely. This is a common problem. Sometimes urine flow stops entirely, but this doesn’t have to happen in order for kidney damage to occur. It’s the increased pressure in the bladder that causes damage.

Creatinine is an end-product of protein metabolism, and since it is removed by the kidney, it’s a good indicator of kidney function. The higher the creatinine level, the worse the kidney function. Creatinine level (along with age and sex) are used to estimate GFR, a direct statement of a person’s kidney function.

A (stable) GFR of less than 15 is considered stage 5 kidney failure, which usually means dialysis will be necessary to preserve life. Note that creatinine itself isn’t the problem; it’s a marker for the fact that the kidney can’t remove all the other waste products, which will then build up and make a person very ill.

When a person with urinary obstruction develops a creatinine level over 6, it’s likely that they will have permanent kidney damage, but I have seen people with higher levels recover and some with lower levels experience permanent kidney function loss. My guess is that you were only a few days away from having permanent damage.

A trans-urethral resection of the prostate (TURP) is a traditional treatment for an enlarged prostate. Although newer treatments are often used in situations where there is time to spare, a TURP is a routine for the type of obstruction you had. There are possible long-term side effects from a TURP, such as erectile dysfunction, but those are usually noticed immediately after surgery and often get better over time.

Finally, a plea: Make sure your doctor has your up-to-date contact information.

Email questions to [email protected].