Joey Wahler (Host): A look at kidney health on this episode of Curating Care, a podcast brought to you by St. Clair, health expert care from people who care. Thanks for listening. I'm Joey Wahler. Joining me is Dr. Matthew Pesacreta. He's Chief of Nephrology at St. Clair Health. Hi there, Dr. Pesacreta. Thanks for joining us.

Dr. Matthew Pesacreta: Hi, Joey. Thank you very much.

Host: Great to have you aboard. So first, as you well know, Nephrology is a specialty of Adult Internal Medicine and Pediatric Medicine that concerns the study of the kidney, specifically normal kidney function and kidney disease. So first, give us a little background, if you would please, on why you chose this particular field.

Dr. Matthew Pesacreta: Sure. I'd be glad to. I was the first physician in my family, and I had the exposure to physicians as many kids do with seeing a pediatrician, then as I got older, different specialties. And what I really liked was the ability for physicians to develop relationships with patients and care for them over long periods of time. And so, when I was in medical school at the University of Pittsburgh, their main decision tree, and there's some specialties that are outliers like Radiology and Psychiatry, but the main decision tree is Surgery or Medicine.

And once I decided to go into Internal Medicine, I was already married and my wife is a nurse. And we sat down and went over the pros and cons of all different specialties, and really was based upon interest and the ability to develop longitudinal relationships with patients and Nephrology really just fit the bill for me.

Host: So, it sounds like a lot of planning and thought went into it, both by yourself and your spouse.

Dr. Matthew Pesacreta: Absolutely.

Host: Sounds like a good way to go, to say the least. So, switching gears, simply put, for those uninitiated, what is actually the function of our kidneys?

Dr. Matthew Pesacreta: The function of the kidneys, you'll hear people say in broad terms that the function of the kidneys is to "clean the blood", which is true. Because the kidneys are the main way our body eliminates nitrogenous waste. You know, the kidneys do so much more. They really regulate not only the fluid balance in the body, but also the electrolyte balance of sodium, potassium, acid-base balance, mineral balance, and play a key role in controlling the blood pressure. Most people don't appreciate that aspect. And in addition, the kidneys, although they're cleaning the blood, they're also secreting multiple hormones, including those responsible for controlling the red blood cell count or anemia in our bodies. So, cleaning the blood is one of multiple things that the kidneys do.

Host: So, it sounds like the kidneys almost serve as kind of a traffic cop at the intersection of all these different functions in our body, things coming and going and everything else, right?

Dr. Matthew Pesacreta: I like that description, because there's multiple sensors throughout our bodies and a lot of the feedback mechanisms go to the kidney, and then the kidney adjusts from there.

Host: Indeed. So, what can our listeners do on their own to keep their kidneys healthy?

Dr. Matthew Pesacreta: To keep the kidneys healthy, first and foremost, you have to know if you have kidney disease or not. We check a combination of blood and urine tests through the primary care physician, usually, to find out if you have kidney disease. And so if it's okay with you, I'll explain how it's checked first before we talk about how they might be able to keep their kidneys healthy.

Host: Please.

Dr. Matthew Pesacreta: We check a blood test called the creatinine, and what that really is is a muscle breakdown product that we all have going through our body. This creatinine is excreted by the kidneys. And so, if the kidneys are not working for some reason, that creatinine number goes up. And so, the blood test creatinine can get plugged into a formula that takes into consideration your age and your gender. And it spits out something called a GFR or glomerular filtration rate. What that really is, is an estimate of kidney function. And so, a normal level is between about 90 and 120. So, it's not a perfect match to percent of kidney function, but it's close.

There are some limitations. You know, these studies were validated with patients over the age of 65. And you really have to be in a steady state for three months for them to be valid, but it gives us a good measure. And then, the urine test that we check, we're looking for blood or protein in the urine, which can also be markers of kidney disease. And so once we find out, based upon blood and urine tests, if people have kidney disease, which is broken down into different stages. Stage I would be that GFR or percent of kidney function greater than 90%, but having protein or blood in the urine. Stage II is 60-89%, IIIA is 45-59%, IIIB is 30-44%. Stage IV kidney disease is 15-29%. And stage V is less than 15%. So, we utilize the amount of protein to further break it down, but those are the main classes.

And I think that it's important for the listeners to know that there is a declining kidney function as we all age. And so, we all lose about 1% of kidney function after the age of 50. And so if I have a 90-year-old with 50% kidney function on that GFR, they may or may not actually have kidney disease. And so, we always keep that in mind.

But back to your initial point, you know, what can listeners do? The one thing that always concerns me is that I hear advertisements, doing this, drinking this supplement, drinking this juice. Unfortunately, none of that is really true. As we'll talk about the causes of kidney disease, it's really important if patients have diabetes to control their sugars, if patients have high blood pressure for them to control their high blood pressure. And then, all people should avoid chronic use of over-the-counter medications unless prescribed by a physician. There are certain instances, but sometimes I'll hear that patients have been taking medications like non-steroidals for decades just based upon some generalized aches and pains, and unfortunately that can cause some kidney disease in itself.

Host: Overtaking acetaminophen on our own can contribute to kidney issues, yes?

Dr. Matthew Pesacreta: It can. Often people will just worry about liver disease with acetaminophen. But in actuality, there's an entity that we call chronic analgesic nephropathy. And so, even long-term use of acetaminophen can cause problems also.

Host: Gotcha. So, you mentioned getting into the causes. Before we do that, I should mention that about one in three Americans are estimated to be at risk of having kidney disease, yet not many are aware of having it, simply because kidney disease doesn't always have overt symptoms. Some patients only find out when their kidneys are failing. So, that being said, doctor, how important is it that people get their blood checked for the things that you were just talking about a moment ago? And how often should they be doing that?

Dr. Matthew Pesacreta: I think that's a very important point. When people are young, women tend to be better than men about following with either primary care physicians or OB-GYNs. But I do think it's important for males in their 20s, but certainly 30s, 40s, and 50s, to follow with a primary care physician on a yearly basis.

And I think that, even for those individuals who don't feel that they have any health problems, it makes sense and it makes sense to check blood work and urine tests probably about once a year. That will really prevent anything from sneaking up on you and will alert any red flags through the blood work to be able to see a nephrologist if warranted.

Host: Okay. So as mentioned, we're going to have you talk about the common causes of kidney disease and what would those be.

Dr. Matthew Pesacreta: The most common causes are diabetes and high blood pressure. They actually account for about two-thirds of the cases of chronic kidney disease and end-stage renal disease in the United States. And so, they're two very common medical conditions. And what I encourage patients to do is to work on those factors because not everybody with diabetes and not everybody with high blood pressure will develop chronic kidney disease, but it's possible.

And so, after we're out of that major lump sum of two-thirds between diabetes and high blood pressure, there are several other entities that can cause chronic kidney disease. One of them has a general term called chronic interstitial nephritis. That's really a pathological diagnosis. But what it means is in a chronic inflammatory state within the kidneys, they can happen whenever you take too many of those over-the-counter pain medications or individuals with multiple issues with kidney stones over time can develop that chronic interstitial nephritis.

Another significant portion is inherited kidney disorders, the most common being polycystic kidney disease. The majority of time, there's a family history and individuals will often know whether they're at risk for polycystic kidney disease. But as I tell patients, family history has to start somewhere. And so, that is also a fairly significant part.

The less common causes, one would be something called glomerulonephritis, which is more of an acute inflammatory process. So, something that happens rather abruptly. Each kidney has about a million filtering units. And for one reason or another, sometimes an immunological condition like lupus, or something more rare, can cause an acute inflammation within those units, those filtering units within the kidney, and cause abrupt changes.

And then lastly, but also very significant, is some people have developed kidney failure related to what we call obstruction. In other words, there's a problem with the urine flow between the kidneys. to the bladder and out of the body. And in men, a common cause is an enlarged prostate. And then in women, there are different causes, but it still can be a significant issue with respect to kidney problems, and particularly because it is reversible if caught early.

Host: And when there are symptoms, because we mentioned earlier there often are not, which ones might a patient with kidney disease notice?

Dr. Matthew Pesacreta: Great question. And that's back to our other point of why people should get checked on a routine basis. And you really pointed out nicely that kidney disease in itself usually does not have any symptoms until it becomes fairly advanced. And if kidney disease is advanced, I'd say less than 20% total kidney function, patients can develop issues with swelling in their legs, shortness of breath related to fluid overload, loss of appetite, confusion, and in worst case scenario, seizures or even death.

Host: And so, in terms of treatment options, nowadays, what are the most common ones?

Dr. Matthew Pesacreta: Great question. And that's why we try to focus on the diabetes and the high blood pressure for those patients afflicted with those processes. And so, for people with high blood pressure, we tell them there's certain blood pressure medications we'd like to use for people with kidney disease. And the goal blood pressure is generally less than 130/80. For patients with diabetes, there are certain diabetic medications that we like to use. But the overall goal is for them to get their A1c or their three-month average less than 7%. And outside of that, we still have other avenues.

Commonly advertised these days are medications called SGLT2 inhibitors, which actually have changed the ballgame a little bit. I really have high hopes. It's for people specifically with protein in the urine, but the early data shows that the delay to kidney failure can be put off for years. And so, hopefully, those medications will further help us decline the rate of end-stage renal disease or kidney dialysis in the United States.

Host: And speaking of dialysis, I'm sure there are a lot of variables that go into it in each individual case. But generally speaking, who's a candidate for that, who's not a candidate?

Dr. Matthew Pesacreta: It's a good question. You know, in our aging population, the vast majority of patients are candidates for dialysis. But what we do is we, obviously, investigate every patient individually. And so, for patients who are in my patient population on the younger end, you know, 60s, 70s, if their kidneys are gradually declining over time, say related to a combination of diabetes and high blood pressure, the vast majority of them, we prepare for dialysis. Mentally, we start talking about it when the kidney function's less than 30%, but dialysis itself usually does not start until about 10-15%.

One of the things I'd like to point out, we try to be very aggressive at getting patients to be evaluated for kidney transplants. Now, unfortunately, there's more patients waiting for transplants than organs available. And so, the transplant centers locally, UPMC and Allegheny Health Network, they have their own criteria that will say whether or not patients are or are not candidates for transplant. But in general, with respect to dialysis, most patients can tolerate dialysis. And a lot of it has to do with their other medical issues, whether or not it's worth to pursue dialysis. And the way I phrase it like that, if we have someone with advanced cancer or advanced dementia, we have conversations with the family at that time. And we say we can extend life potentially, but we always have to worry about quality of life, and what would that patient want if they were able to make their own decisions.

Host: And that's why I mentioned that I'm sure in each individual case, there are a lot of factors that have to be weighed. So in summary here, doctor, what would you tell people listening about, again, the importance of maintaining good kidney health by staying on top of things and just getting things checked regularly before it's too late?

Dr. Matthew Pesacreta: That's right. You hit the nail on the head. I think the first step is always finding out whether or not you have chronic kidney disease. And if you do, you should be seeing a nephrologist. Usually when that kidney function gets less than 60%, it gets on people's radar. And long term, like I said back to the beginning of the discussion, our goal is long-term longitudinal relationships with patients. That's what we enjoy. And our goal is always to prolong kidney function as long as we can.

Host: Well, folks, we trust you're now more familiar with good kidney health. Dr. Matthew Pesacreta, thanks so much again.

Dr. Matthew Pesacreta: My pleasure, Joey. I really appreciate the opportunity to discuss this topic.

Host: And the same here. Now, for more information, please do visit stclair.org. That's S-T-C-L-A-I-R dot org. To contact Dr. Pesacreta, you can call 412-489-6919. If you found this podcast helpful, please share it on your social media. I'm Joey Wahler. And thanks again for listening to Curating Care, a podcast brought to you by St. Clair, health expert care from people who care.