Why do some of our organs come in pairs, but other organs do not? We have two eyes, two lungs, two kidneys, but only one nose, one heart, one stomach, etc. Oh well, if someone knows the answer, please forward it to me. In the meantime, since I've got your attention, let's talk about the pair of kidneys that sit in the middle of the abdomen toward the back.
The main purpose of the kidneys is to filter and reprocess blood. It's an extremely complex process and cannot simply be likened to a sieve. Wastes and extra water are removed to become urine, which flows from the kidneys to the bladder to be excreted whenever we feel the need to urinate. But the normal proteins and cells of the bloodstream that we need are returned back to the blood. In this way, the kidneys regulate the body's levels of many substances, sometimes keeping them to a very narrow, normal range.
But the kidneys also are important for other reasons. The kidneys release three hormones: one that stimulates the bone marrow to produce red blood cells, another that helps regulate blood pressure, and the third is actually the active form of vitamin D, which helps maintain calcium levels.
Frequently, patients will have tests that check "kidney function." This is done to know how efficiently the kidneys are filtering and reabsorbing. Fortunately, a decline of 30 to 40 percent of kidney function is not a problem. It's when function declines to the 25 percent level that serious health problems arise.
The most common blood test for kidney function is the Glomerular Filtration Rate (GFR), and the most common urine test for kidney function is the urinalysis. The GFR is a laboratory calculation based on the level of creatinine, which is a break-down product of muscle and is usually produced at a fairly constant rate by the body. Since creatinine is chiefly filtered out of the blood by the kidneys with little or no reabsorption, levels in the blood and urine may be used to calculate the filtration rate. So, the GFR can tell if the filtering of the kidney is deficient. As for the urinalysis, impaired kidneys allow a protein called albumin to leak into the urine, a situation called proteinuria.
So it makes sense to protect the kidneys as much as possible. Diabetes and high blood pressure are two of the most common conditions that severely impact proper, healthy kidney function. High sugar levels in diabetes directly damages the microscopic filtering cells of the kidneys while high blood pressure damages the microscopic blood vessels of the kidneys.
So if you are diabetic or have high blood pressure, make certain you are controlling the conditions with proper dietary changes, and taking medications as indicated. And as always, quit cigarettes and get plenty of exercise and good quality sleep.
• Agnes Oblas is an adult nurse practitioner with a private practice and residence in Ahwatukee Foothills. For questions, or if there is a topic you would like her to address, call (602) 405-6320 or email firstname.lastname@example.org. Her website is www.newpathshealth.com.