Specialist Q&A: What Can a Nephrologist Do for You?

Rovin: Generally speaking, everyone who is in nephrology will have completed an internship and residency in general medicine. That would be three years of training, and that covers all the specialties of medicine. After that, we go into the fellowship part of the program, which is a minimum of an additional two years of training.

My fellowship was four years because I spent quite a bit of time in a laboratory, because I like to do research as well as take care of patients; so a minimum of two years and a maximum of up to four years.

One of the main reasons is the finding of blood or protein in the urine from a urinalysis. This would not necessarily be blood the patient noticed, because it's often microscopic. Another big reason is when somebody is doing laboratory studies and they find that kidney function is not normal.

A very common lab test called serum creatinine measures kidney function. The creatinine test is higher in people who have kidney dysfunction, which is related to what we call the estimated glomerular filtration rate, a measurement of how well the kidney is functioning. You get both bits of data back when you order a lab test.

We also get a lot of referrals for people with difficult-to-treat high blood pressure. Kidney physicians treat resistant hypertension. While most internists will manage most hypertension successfully, when they have complicated cases or have cases that don't respond, they're often referred to a kidney physician.

Another reason we see patients is because they have an electrolyte imbalance, such as high or low sodium or potassium levels.

We need to know the medications you're on and when they were started and changed. What I really appreciate is when they bring a list of medications with the doses and times they're taking them.

I like to know what their blood pressure has been running. I want to know if they have elevated blood pressure and how long they've had it. I also like to know if they have other diseases that might predispose [them] to kidney involvement or kidney injury. In the United States, the most common of those is diabetes. We see many, many patients with both type 1 and type 2 diabetes. I like to know how long a patient has had diabetes, whether they require insulin or not, and whether they've had other complications of diabetes where it can affect other organ systems, such as the eye, heart or nervous system.

Some of our diseases do run in families, so I like to know a family history. If they don't know somebody has kidney disease, oftentimes I'll ask if maybe somebody mentioned someone has blood or protein in their urine. Sometimes they do know a family member [who] has gone on to kidney failure and is on dialysis. Then, usually, we take a very intensive past medical history to understand what other diseases a patient may have, because a lot of our patients are older and have other comorbid conditions, such as concomitant heart disease, hypertension and diabetes.

In my clinic, I often get a good idea of what's going on from a very comprehensive history. We get good information from a physical examination, such as whether the person has swelling, rashes or signs of other systemic diseases. For example, in a lot of my lupus patients, they might have joint inflammation.

When a person comes to the clinic, we ask them to provide a urine sample. We spin it down to look at it under the microscope, which helps me understand what might be going on in the kidney. We'll do a blood panel to understand their current kidney function. We'll look at their electrolytes. We'll often look at other laboratory values that might be affected by the kidney not working properly; for example, calcium or phosphate levels and the amount of protein they have in their blood is important. We carry a lot of protein in our blood, and if you have severe protein loss through the kidneys, those levels go down.

Very often, we will ask a patient to collect a 24-hour urine sample ahead of time and bring it to clinic with them. That allows me to get a more accurate measurement of their kidney function. It also allows me to see accurately how much protein they might be losing. A lot of our diseases are associated with protein loss in the urine. If I think they have kidney stones, I would potentially get an image of the kidney using an ultrasound machine; it gives us a picture of what's going on in the kidney.

I often do that to understand how the kidneys look because kidneys should be a certain size. For patients with long-standing kidney disease, their kidneys will decrease in size. There can be a scar you can see from an ultrasound, on what we call the renal cortex, the part of the kidney indicating long-standing kidney disease.

The laboratories are generally done as they're leaving the clinic, so there's an on-site place where blood is drawn. Then X-rays often have to be made with an appointment and follow-up later. It ultimately depends on what our index of suspicion is as to what the kidney disease might be. For example, in a lot of these immunologic kidney diseases, we often have to do a kidney biopsy, where we take a couple of pieces of the kidney to look at under the microscope.

We do see one-and-done or two-and-done occasionally with patients who might have had an acute kidney injury. But for the vast majority of our diseases, we develop a long-term relationship with the patient and we tend to follow them for many years. This is because a lot of our diseases are chronic. For example, if you have diabetes and kidney disease, that's a long-term relationship between you and the kidney doctor and the person taking care of the diabetes, the internist, family medicine doctor or endocrinologist. Even in the immunologic kidney diseases I see, a lot of times we treat the patient and get them to go into remission. But a lot of diseases have the risk of relapse, so we see the patient periodically.

Once a patient is diagnosed with kidney disease, if it's not something that resolves quickly and completely, we tend to see them in follow-up long term. I often see my patients depending on the intensity of therapy. If I'm right at the beginning of the therapy, I'll see the patients every month or every other week, depending on if they have intensive immunosuppressive therapy. More than likely, I'll see the patient three or four times a year. Eventually, if they become stable and things aren't progressing, I'll see them once or twice a year. It is quite variable.

Can we somehow create a system where we can have an artificial kidney? We are now trying to engineer replacement kidneys. We're in the very early stages of this. But if we could do something like that, could we then put that device or engineered organ in a patient, and then they would be able to come off dialysis? That would change the lives of thousands and thousands of patients who require continuous dialysis to maintain their lives. That would be the golden cup of discoveries.

People are working on this, and it's not science fiction. It's real science and it's progressing slowly, but it's progressing forward. I don't know if it will be in my lifetime as a practicing nephrologist, but certainly, in the future, there's a definite chance that this could be a therapy.