nephrologist

n. expert in nephrology; expert in kidney diseases

A nephrologist is a physician who has been trained in the diagnosis and management of kidney disease, by regulating blood pressure, regulating electrolytes, balancing fluids in the body, and administering dialysis. Nephrologists treat many different kidney disorders including acid-base disorders, electrolyte disorders, nephrolithiasis (kidney stones), hypertension (high blood pressure), acute kidney disease and end-stage renal disease. Nephrology is a subspecialty of internal medicine. In the United States, after medical school nephrologists complete a three year residency in internal medicine followed by a two year (or longer) fellowship in nephrology.
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A medical specialist in nephrology (the study of the kidney or "kidney-ology").

[neh-FROL-uh-jist]
A doctor who specializes in diagnosing and treating kidney disease.

a doctor who treats people who have kidney problems.