Starting from the basics: The kidneys' structure and function

I want the first post to address the absolute basics about the kidneys. Looking at this from a patient's perspective, I am often surprised by how little some of my patients know about the kidneys. I guess the lay press has a done a pretty good job of educating everyone about the other "more glamorous" organs! Everyone realizes the important roles played by the heart, the brain....even the liver gets its fare share of the limelight with everyone realizing the connection between liver disease and alcohol intake. The questions that I get asked often range from, "what do the kidneys do", "what/where are they", "why should I be worried about kidney disease"?


"Image courtesy of [Dream Designs] / FreeDigitalPhotos.net"

So here goes:
The kidneys are two bean shaped organs in your flanks, just below the rib cage. They range in size from 8 to 14 centimeters (or 3-4 inches). They are the silent workhorses who work 24x7 to clean your blood of impurities and toxins that build up from the body's metabolism, produce hormones essential to make blood cells (erythropoietin) and making sure that your bones stay healthy (via vitamin D production), dump excess acid out from your system, control your blood pressure, etc. About 380 gallons (1440 liters) of blood flows through the kidneys every day! It is not surprising then that kidney disease is associated with wide ranging complications (which I will cover over the later posts). 


Comments

  1. Kidney_BoyMay 24, 2013 at 10:43 AM

    I think you made a mistake, kidneys cannot filter 1440 liters a day that would be a GFR of 1 liter per minute.

    ReplyDelete
  2. DrVCMay 25, 2013 at 2:22 PM

    Duly noted. I apologize. "Filter" is probably not the right word to use. The words I should have used is "the amount of blood flowing through the kidneys every minute". This is based on the kidneys getting 20% of the cardiac output of 5 liters a minute. Hence, 1 liter/minute = 1440 liters a day! By the way, I am a big fan of your blog, Precious Bodily Fluids, and have been reading it since I was a fellow. You are a prolific blogger and I am amazed how do you find the time to do so much! I loved the post where you shred Dr Spry's views on alcohol and kidney disease; which is why I wrote my current post. Thank you, also for mentioning my blog on your last post.

    ReplyDelete

Post a Comment

Popular posts from this blog

I do not want dialysis: how long can I expect to live, and how would I feel?

Image
I often see patients in my office who refuse dialysis (should it become necessary) for their advancing kidney disease. I divide these patients in to two categories. The more common category is patients who refuse it because of the "fear of dialysis". They could have trouble understanding dialysis and what potential benefits they could derive from it. They would often make good dialysis candidates who have more to lose than gain by refusing dialysis therapies. The other category is the patient who rightfully refuses dialysis because she or he would not make a good candidate for such treatment. There could be multiple reasons for that. It could be advanced age and frailty, presence of other severe disease conditions like heart failure or metastatic cancer, etc. In such cases, it is hard to always predict if dialysis would add anything to the quality/quantity of life. And often, patients are simply looking at the "big picture". So the questions that come up in
Read more

Is a vegan or vegetarian diet better for patients with kidney disease?

Image
Over the last few decades, we have seen the accumulation of evidence that supports the health benefits of plant-based diets. Vegetarian diets have been shown to be associated with a lower incidence of obesity, hypertension ,  diabetes , and coronary artery disease . Since all these entities are risk factors for chronic kidney disease (CKD), it might be reasonable to assume that these diets might actively reduce the risk of CKD development and progression. However, at the very outset, let me emphasize that any diet, vegetarian or not, comes with the same restrictions that are advised for patients with CKD . For instance, potassium intake might need to be restricted in advanced CKD. Fruits, a significant portion of the vegetarian diet, are an important source of potassium, and will need to be appropriately restricted. So you have to watch what you eat regardless. More importantly, you owe it to yourself to know what exactly is there in the food that you eat.
Read more