What Is a Nephrologist?

Medically Reviewed by Jabeen Begum, MD on September 18, 2024
8 min read

A nephrologist (pronounced nuh-frah-luh-jist) is a medical doctor who specializes in diagnosing and treating conditions that affect your kidneys.

Some conditions, such as diabetes, obesity, heart disease, and high blood pressure, can raise your chance of developing a kidney condition. And if you have a kidney condition, you may develop high blood pressure and heart disease, even if you didn't have these conditions before. Chronic kidney disease may also lead to complications, such as anemia, osteoporosis, a weakened immune system, or an irregular heartbeat. 

Kidney conditions are on the rise around the world; kidney disease ranks as the 12th leading cause of death globally and the ninth leading cause in the U.S., where about 15% of adults are believed to have chronic kidney disease (CKD). Unfortunately, 90% of these people don't realize it or don't visit a specialist until their condition has become serious and expensive. 

If you have symptoms or your general practitioner sees signs of a kidney condition, they will likely refer you to a nephrologist who can develop a treatment plan to help you manage low-functioning kidneys. In some cases, your kidney damage may even be reversible if you catch and treat it early.

Nephrologist vs. urologist

A urologist is a medical doctor who specializes in diagnosing and treating conditions of your reproductive organs, adrenal glands, and urinary system. Your urinary system includes your:

  • Kidneys, which filter your blood to remove waste and extra water (urine or pee)
  • Bladder, which is where pee that your kidneys have filtered is stored until you can eliminate it
  • Ureter, which are tubes that connect your kidneys and bladder
  • Urethra, which is the tube through which you eliminate pee from your bladder

Both nephrologists and urologists can diagnose and treat kidney conditions, but if your condition is specific to your kidneys or kidney function, a nephrologist is probably the best doctor to treat you. A urologist is probably your best option for a condition affecting the rest of your urinary system, your reproductive organs, or if you need surgery, like for instance, for kidney stones. Urologists have training in surgery while nephrologists typically don't.

Nephrology is a specialty within the internal medicine field. Sometimes people also call nephrology renal medicine because it is specialized in kidney (renal) care. Your kidneys are important organs that filter your blood to remove waste chemicals and extra water. You have two kidneys in your back below your rib cage. Each kidney has millions of filtering units called nephrons (this is how nephrology gets its name). By filtering your blood, your kidneys help keep the water, salts, and minerals in balance in your blood. Your blood needs to be in balance for your other organs and muscles to work well.  Having low-kidney function can put you at risk for kidney disease, kidney failure, or end-stage renal disease, where you require dialysis regularly. Your kidneys also make hormones that:

  • Make red blood cells
  • Control your blood pressure
  • Help keep your bones strong

Nephrologists are internists who diagnose, treat, and manage acute and chronic kidney conditions, such as kidney failure and end-stage renal disease. They're experts in renal health, and they identify issues with your kidneys to help you maintain good health. They may also treat conditions related to your kidney function, such as high blood pressure, fluid retention, and electrolyte and mineral imbalances. In addition, these specialists are in charge of kidney dialysis treatment — both hemodialysis and peritoneal dialysis — and kidney transplants and their follow-up care. 

Seeing a nephrologist for your care puts you in the hands of experts who can recommend the best treatment plan. They stay up-to-date on medical advancements for your kidney condition to ensure that you have the most accurate and comprehensive care.  

 

Nephrologists are specialized medical doctors who have advanced training in the anatomy and function of the kidneys. It takes over a decade of training to complete medical school, a residency in internal medicine, and a fellowship in nephrology.  

In the U.S., the training process in nephrology requires:

  • Four years of medical school to earn a Doctor of Medicine (MD) or Doctor of Osteopathic Medicine (DO) degree
  • A 3-year residency in internal medicine
  • A 2- to 3-year fellowship in nephrology, with the option for an additional yearlong fellowship in interventional nephrology or transplant nephrology
  • Passing a certification exam from the American Board of Internal Medicine for board certification in nephrology

Most people don't go to a nephrologist without a referral from their primary care doctor. Your doctor may refer you to a nephrologist if you have risk factors for kidney disease, such as:

  • A family history of kidney disease. If your parents or siblings have kidney disease, you may be at greater risk of developing it too. In this case, your doctor may refer you to a nephrologist, who can help you prevent developing it or start treating it at it's earliest stage.
  • Diabetes. You have a higher risk of developing kidney disease if you have diabetes because the condition can damage your kidneys.
  • High blood pressure. This can make your blood vessels less stretchy, which reduces the amount of blood and oxygen that can get to your kidneys. This may damage them over time.

Your doctor will also refer you to a nephrologist if you have symptoms of a kidney condition, such as:

Chronic urinary tract infections

Urinary tract infections (UTI) are typically localized to your bladder (cystitis) or urethra (urethritis). But if you have UTIs frequently, you're at greater risk for the infection to travel up to your kidneys. A kidney infection (pyelonephritis) increases your risk for developing kidney disease, permanent kidney damage, or kidney failure. Symptoms of a UTI include:

  • Pain in your flank, belly, pelvis, or lower back
  • Pressure low in your pelvis that may feel like you really need to pee
  • Pain when you pee
  • Cloudy and smelly pee
  • Leaking pee uncontrollably or not being able to make it to the bathroom before pee leaks out
  • Feeling like you have to pee or peeing more than usual
  • Blood in your pee
  • Fatigue
  • Fever and chills
  • Nausea and vomiting
  • Confusion or brain fog

Recurring kidney stones

Kidney stones are mineral- or salt-based crystals that form inside your kidneys. They may form, for instance, if you don't drink enough water to keep your pee diluted enough to prevent them from forming. Kidney stones can increase your risk for kidney infections, acute kidney injury, frequent UTIs, and CKD. Symptoms of kidney stones are similar to those of UTIs:

  • Nausea and vomiting
  • Blood in your pee
  • Pain when you pee
  • Unable to pee
  • Feeling like you have to pee more often than usual
  • Fever and chills
  • Cloudy and smelly pee

Foamy pee

Most people will see a few bubbles in the toilet bowl right after they pee, especially if they've peed a lot and fast. A single layer of bigger bubbles that don't stick around for long is normal. Foamy or bubbly pee is when you see multiple layers of small to medium bubbles right after you pee and they may not disperse. Doctors consider this an early sign of kidney damage because it shows that you have a lot of protein in your pee (also called proteinuria).

You normally have a bit of protein waste in your pee, but if you have a lot of protein in your pee, it may mean that your kidneys aren't able to reabsorb the proteins you need from your blood. This probably means you have some kidney damage. Aside from foamy pee, other symptoms that you may suggest kidney damage include:

  • Swelling in your face, belly, feet, or ankles
  • Peeing more often than usual
  • Shortness of breath
  • Fatigue
  • Nausea and vomiting
  • Loss of appetite
  • Muscle cramping, especially at night
  • Puffiness around your eyes, especially first thing in the morning

If you have foamy pee, your doctor will likely refer you to a nephrologist who will do a series of blood tests to check your blood and kidney health. Such tests may include blood urea nitrogen, serum creatinine, and protein-creatinine ratio.

Itchy skin and joint or bone pain

If you're experiencing bone and joint pain along with itchy skin, you might have a condition called renal bone disease (also known as mineral and bone disorder in CKD). It happens when your kidneys can't filter your blood or regulate your hormones the way they normally would because of damage. This throws the balance of calcium and phosphorous off in your blood. If untreated, this condition can lead to weakened bones and heart and blood vessel problems.

Talk to your doctor if you have bone and joint pain as well as other symptoms of kidney problems.

A nephrologist is a doctor who specializes in diagnosing and treating conditions that affect your kidneys, such as kidney failure and chronic kidney disease (CKD). Nephrology is a specialty within the internal medicine field. If you have symptoms of a kidney condition, your doctor will likely refer you to a nephrologist who can help you prevent further kidney damage.

At what stage of kidney disease should you see a nephrologist?

Ideally, you will get a referral to a nephrologist as soon as you show signs or have symptoms of kidney disease. Doctors divide kidney disease into five stages based on how much kidney function you have. Kidney disease often gets worse over time. In stages 1-3, your kidneys still have enough function to filter your blood. In stages 4-5, your kidneys either aren't able to function very much, or they may have stopped functioning altogether. No matter how much function your kidneys still have, your nephrologist's goal will be to help slow the damage to your kidneys and keep them working as long as they can. If you are at the point where your kidneys have stopped working, they can help you with dialysis and evaluate you for a kidney transplant. 

What are the first symptoms of kidney disease?

You may not know you have kidney disease in the earliest stages because you may not have any symptoms or you may overlook some of them. If you're at risk of kidney disease because you have high blood pressure, diabetes, a family history of kidney disease, or you're older than 60, look out for the following, especially if you have more than one symptom at a time:

  • Fatigue or low energy
  • Trouble concentrating or brain fog
  • Trouble sleeping
  • Dry and itchy skin
  • The need to pee more than usual
  • Blood in your pee
  • Foamy pee
  • Swelling around your eyes
  • Swollen ankles and feet
  • Low appetite
  • Muscle cramping