December 13, 2006
Question from Houston, Texas, USA:
My grandson was diagnosed at age two and a half. He is now 12. This summer, he showed protein in the urine. He has taken two urine tests, both having complete rest for two days with the urine test on the third day. They both tested positive. He will see a kidney specialist at Texas Children’s in January. What do you think we can expect? Will they suggest beta blockers? If so, would he be on them the rest of his life? There are no blood pressure problems and he is quite active. He is very healthy considering he has had ten years with diabetes.
Diabetes-related kidney disease can be very serious. While a kidney biopsy is rather quite definitive, it certainly is an invasive procedure. So, SCREENING tests have been developed., Other than biopsy changes, one of the earlier signs of diabetes-related kidney disease is “leakage” of very small amounts of albumin protein into the urine. These very small amounts of albumin are sometimes referred to as “micro-albumin.” The kidneys can also lose small amounts of albumin due to other kidney diseases, but also during times of fever and after some more vigorous exercise. So, often the urine is collected on quiet days when the person is well.
What the kidney specialist (“nephrologist”) will do hinges in part on many things that you have not noted in your question including, but not limited to, the actual amount of protein, other potential irregularities found, his overall glucose control, and others.
If the two urine tests done so far were random samples or even “first-thing-in-the-morning” samples, they may have only done the SCREENING test which commonly would have been the ratio of albumin relative to a waste product called creatinine. This albumin/creatinine ratio should be less than 30 mcg/mg in this type of sample.
A more quantifiable test is measuring how much albumin is excreted over a period of time, usually with an overnight urine collection following a night’s sleep or even a complete 24 hours. This is measured as the amount of albumin (microalbumin) per minute. With this test, the family would have been instructed to carefully record the time interval during when the urine collection was started and stopped. A normal rate is typically less than 20 mcg/minute.
So, after the nephrologist learns the history and performs an examination, with special attention to blood pressure, and depending upon the results of the previous urine results, he or she may request a timed urine collection or might even discuss the possibility of a kidney needle biopsy (child sedated, skin numbed, a needle is quickly passed through the skin to a kidney). The nephrologist may request more blood and urine tests and might even consider an ultrasound of the kidney.
As for potential treatment, the usual treatment for diabetes-related kidney disease begins NOT with a beta-blocker, but rather a different medicine (also often used to treat blood pressure) called an Angiotensin-Converting-Enzyme inhibitor (“an ACE inhibitor”). There are also ACE receptor blockers. These types of therapies have their own list of benefits and potential risks. Treatment is usually indefinitely and for a lifetime with the goal to prevent further diabetes-related kidney disease progression on to kidney failure.