A nephrologist is a medical doctor who specializes in the care of kidneys and the treatment of kidney conditions. They are also known as kidney doctors. Nephrologists diagnose and treat acute and chronic kidney problems and diseases, including kidney failure, high blood pressure, fluid retention, and electrolyte and mineral imbalances. They also recognize how kidney conditions affect other parts of the body, such as autoimmune diseases and cardiovascular disease. Nephrologists can develop a management plan that helps patients overcome low-functioning kidneys, and in some cases, kidney damage may even be reversible if caught and treated early. They also perform diagnostic tests and procedures such as imaging tests, kidney biopsies, and dialysis treatment. 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. Patients should see a nephrologist if they have signs of kidney problems, such as urinary tract infections, kidney infections, hyponatremia, and other electrolyte disorders, toxic overdoses that require dialysis, and glomerulonephritis.