A person can live with only one kidney, and medical interventions allow individuals to survive without any functioning kidneys. While two kidneys are typical, the body can adapt to having one, or rely on technology and transplantation when neither is present. These situations require varying medical and lifestyle adjustments.
The Vital Functions of Kidneys
Kidneys are bean-shaped organs, each about the size of a fist, situated below the rib cage on either side of the spine. Their main function is to filter waste products and excess fluid from the blood. They also play a role in maintaining the body’s balance of water, salts, and minerals like sodium, calcium, and potassium.
Beyond filtration, kidneys produce hormones that regulate blood pressure, stimulate red blood cell production, and contribute to bone health. Each kidney contains millions of tiny filtering units called nephrons that process about 150 quarts of blood daily, returning most cleaned fluid to the body while producing one to two quarts of urine.
Living with a Single Kidney
Individuals may have a single kidney for several reasons, including being born with only one, donating a kidney, or having one surgically removed due to injury or disease. When one kidney is present, the remaining kidney often compensates by increasing in size and function, a process known as compensatory hypertrophy. This adaptation allows the single kidney to achieve up to 70% to 85% of the function normally performed by two kidneys.
Most people with one healthy kidney lead normal, healthy lives with few long-term problems. They may have a slightly increased risk of high blood pressure or protein in the urine, signaling kidney strain. Regular check-ups monitor kidney function and blood pressure. A balanced diet, hydration, regular exercise, and avoiding excessive alcohol support kidney health. Caution is advised with certain medications, like NSAIDs, and avoiding contact sports is often recommended to prevent kidney trauma.
When No Kidneys Are Present
Without any functioning kidneys, the body cannot effectively remove waste products and excess fluid, leading to a buildup of toxins that is not sustainable for life. In such cases, medical intervention becomes necessary to survive. The two primary life-sustaining treatments are dialysis and kidney transplantation.
Dialysis artificially filters the blood, performing kidney functions. Hemodialysis diverts blood through an external machine for cleansing, typically requiring three to four-hour sessions, three times a week. Peritoneal dialysis uses the abdominal lining as a natural filter, introducing and draining a special fluid. This method can be performed daily at home.
A kidney transplant involves surgically placing a healthy kidney from a deceased or living donor into the recipient’s lower abdomen. The new kidney’s blood vessels connect to the recipient’s, and the ureter attaches to the bladder. Original kidneys are left in place unless causing complications. Following transplant, patients must take immunosuppressant medications to prevent organ rejection.