End-stage renal disease (ESRD) is a condition characterized by the permanent loss of kidney function, leading to the inability of the kidneys to adequately filter waste products and excess fluids from the blood. It is the final stage of chronic kidney disease (CKD) and often requires renal replacement therapy, such as dialysis or kidney transplantation, to sustain life. In ESRD, the kidneys are severely damaged and can no longer perform their essential functions, resulting in the accumulation of toxins and electrolyte imbalances in the body.