Why You Need Your Kidneys Video Transcript

Participants

, Lisa Clark , Jai Radhakrish MD, MRCP (, Leonard Stern MD

Summary

What do you know about your kidneys? Most people are aware that they look something like kidney beans, and that there are two of them-- but that's about it. As you might expect, kidneys are actually quite important. What do kidneys do and why can't you live without them? Tune in to find out.

Webcast Transcript

LISA CLARK: I'm Lisa Clark. Welcome, and thanks for joining us for this webcast. Did you know that more than 20 million Americans suffer from various forms of kidney and urinary tract disease? Of these, about 10 percent -- 200,000 people -- are suffering from chronic kidney failure. They require the use of an artificial kidney machine to stay alive. In order to get a better idea of how the kidneys work and why they are so vital to our health, we're going to spend the next few minutes with two physicians who specialize in the study and treatment of kidney disease.

To my left is Dr. Leonard Stern. Welcome. Down further, Dr. Jai Radhakrishnan. Both men are Assistant Professors of Clinical Medicine at the College of Physicians and Surgeons of Columbia University, and they practice at the Columbia Presbyterian Medical Center. Thank you both for being here.

If I may, begin with a very basic description of what the kidneys look like, where they are located in the body, Dr. Radhakrishnan?

JAI RADHAKRISHNAN, MD: Every person has two kidneys, and they're about in the middle of the abdomen in the back, and they're the size of the fist. They drain into two tubes called the urethrae, into the bladder.

LISA CLARK: What are the basic functions that the kidney performs in the body?

JAI RADHAKRISHNAN, MD: The kidney is a very important organ, and the most obvious function is that it excretes wastes that we produce from our diet and from our metabolism. What's less obvious is that it's the most important organ that controls the composition of the body fluids. In addition, it does produce a number of hormones that deal with body function.

LISA CLARK: Len, if I may ask you, what's the mechanism by which the kidneys actually remove waste from the bloodstream?

LEONARD STERN, MD: The kidney is a filtering organ, so blood is delivered to a very unique apparatus in the kidney called the glomerulus, and there, because of pressure dynamics, a component of the blood is filtered across the membrane, and the first process of creating the urine develops. In this segment of the kidney, in the glomerulus, the composition of that fluid is very similar to blood. The fluid passes through a series of tubules in a structure called the nephron, and there it's modified, heavily modified. A variety of things are reabsorbed that we need, and a variety of toxins are concentrated until the end of the kidney, the end of that nephron segment, drains into something called a papilla, then into the ureter, and then the bladder, and we have what we term "urine," which is a fluid rich in toxic wastes that is excreted.

LISA CLARK: It's a remarkably complex system, and I guess there are a lot of places where things can get hung up along the way.

LEONARD STERN, MD: There are many segments of the kidney where illness can affect the function. For example, there are inflammatory disorders that affect the glomerulus. There are disorders that affect the tubules and the reabsorptive process. There are specific illness that affect the blood vessels that feed the kidney, and then, of course, there are problems with the drainage system and the ureters -- infection, stones, a variety of ailments. Textbooks of ailments.

LISA CLARK: Jai, in addition to filtering waste from the body, the kidneys also regulate electrolytes in the body system. How does that work?

JAI RADHAKRISHNAN, MD: For example, suppose you drink a bottle of orange juice.