A nephrologist is a doctor who specializes in the kidneys. The word comes from the Greek nephros, for kidney. It is pronounced neh-FROL-uh-jist.
That is the dictionary answer. The more useful one is what we actually do, how we are trained, and how we differ from a urologist, which is where most of the confusion lives.
What a nephrologist does
The kidneys filter blood, balance salt, water, and minerals, help control blood pressure, keep the blood from turning too acidic, and make hormones for red blood cells and bone health. Nephrologists treat problems with any of those jobs:
- Chronic kidney disease, at every stage
- Acute kidney injury, a sudden drop in kidney function
- High blood pressure that is hard to control or may have a hidden cause
- Electrolyte problems: sodium, potassium, calcium, magnesium, and acid levels
- Protein or blood in the urine and glomerular diseases
- Diabetic kidney disease
- Prevention of kidney stones that keep coming back
- Polycystic kidney disease and other inherited conditions
- Dialysis, and care before and after a kidney transplant
Most of this is medical, not surgical. We use blood and urine tests, imaging, medications, and sometimes a kidney biopsy.
How a nephrologist is trained
In the United States, a nephrologist finishes four years of medical school, three years of internal medicine residency, and then two or more years of nephrology fellowship. Board certification in nephrology comes from the American Board of Internal Medicine, which you can look up for any physician.
That internal medicine base matters. Kidney problems rarely travel alone. They come with diabetes, heart disease, high blood pressure, and long medication lists, and a nephrologist is trained to manage the whole picture.
Nephrologist vs. urologist
This is the most common confusion, and it costs people weeks.
| Nephrologist | Urologist | |
|---|---|---|
| Type of doctor | Medical specialist | Surgeon |
| Focus | How well the kidneys work | The plumbing: kidneys, bladder, prostate, urethra |
| Typical problems | Kidney disease, blood pressure, electrolytes, protein in urine, dialysis | Stones that need removal, blockages, prostate, tumors, bladder problems |
| Typical tools | Labs, medications, biopsy, dialysis | Scopes, surgery, procedures |
| Kidney stones | Finds out why they form and prevents the next one | Removes the stone that is stuck now |
Some people need both. A kidney stone patient might see a urologist to remove the stone and a nephrologist to stop the next one.
When to see one
The short version: any time your kidney numbers are abnormal on more than one test, protein shows up in your urine, or blood pressure will not come down on three medications. Earlier is better, and a referral is not a sign you are headed for dialysis. Most people who see a nephrologist never need it.
The exact lab thresholds, what the first appointment looks like, what to bring, and the questions worth asking are all in our guide on when to see a nephrologist.
Seeing a nephrologist in Houston
Remix Medical is a physician-owned practice. Uday Khosla, MD, a board-certified nephrologist, sees patients in Montrose near the Texas Medical Center, East Houston, Katy, and Groesbeck, and by video visit anywhere in Texas. You see the same physician at every visit, and our primary care, pain, and lung physicians share the same chart, so kidney care stays connected to everything else. Most plans are accepted, including Medicare, Medicare Advantage, and Texas Medicaid; some HMO and Medicare Advantage plans need a referral, and our office can check. Book an appointment or ask for a video visit.