The nephrologists, also known as kidney doctors are a physician who deals with the diagnosis and management of kidney disease. The kidneys are vital for maintaining normal fluid and electrolyte balance in the body. They commonly treat chronic kidney disease (CKD), polycystic kidney disease (PKD), failure, kidney and high blood pressure and are educated on all aspects of kidney and dialysis. People with kidney problems may be referred to nephrologists by their primary care physician or they may choose to go to a kidney doctor if they believe they have issues with their kidneys.