A nephrologist is a medical doctor who specializes in the care of kidneys. They diagnose and treat kidney conditions and kidney failure, as well as recognize how kidney conditions affect other parts of the body, including autoimmune diseases, cardiovascular disease, and high blood pressure. They also treat associated issues like fluid retention, electrolyte and mineral imbalances, and urinary tract infections. Nephrologists are experts in renal health, and they work to identify issues with the kidneys to help maintain good health. They commonly treat chronic kidney disease (CKD), polycystic kidney disease (PKD), acute renal failure, kidney stones, and high blood pressure. They also manage dialysis care for people with end-stage renal disease. To become a nephrologist, doctors must complete four years of college, four years of medical school, three years of residency, and two to three years of a fellowship. Common tests and procedures that nephrologists perform include imaging tests, kidney biopsies, and dialysis treatment.